February
2025
www.chemengonline.com
Exploring
Choked Flow
page 21
Membranes
Fire and Explosion Safety
Heat Exchange
Laboratory Equipment
Alarm Management
Solids Blending and Segregation
Built to Last.
Proven to
Perform.
For 80 years, Hapman has
been manufacturing robust,
high-quality equipment that
stands the test of time—some
of it still running strong after
more than 40 years.
Where exceptional
material handling begins.
√ Challenging Materials
√ Safe
√ Efficient
√ Trusted Experts
View Our Full Product Line
Celebrating 80 Years of Excellence.
Partner with a company trusted for generations.
Contact us today:
(800) 427-6260 | Hapman.com
For details visit adlinks.chemengonline.com/88111-01
E line Conveyor
For maximum protection
against dust explosion
www.chemengonline.com
February 2025 Volume 132 | no. 2
Cover Story
21
Gas-Flow Calculations for Sonic Choking — Revisited
Gas compressibility can lead to choked flow in piping systems. Presented
here is an overview of choked-flow geometries in pipes, and also
examples of how choked flow arises in different pipe layouts
.In the News
5
Chementator
Flow chemistry yields a more sustainable route to
isocyanates; Pilot plant planned for thermocatalytic
ethanol-to-butene process; Single-step process for
electrified ethylene production; Deepwater RO could
cut energy use and environmental impact of seawater
desalination; and more
10
Business News
Messer to construct $70-million air separation unit in
Arkansas; Covestro to expand polycarbonate production
site in Ohio; BASF to sell Styrodur insulation materials business;
Bayer acquires biofuel feedstock assets from Canadian firm; and more
12
21
Newsfront Heat Exchange Solutions Support
Sustainability Developments in heat exchange technologies promote
efficiency, reliability and cost-effectiveness
.Technical and Practical
18
5
Facts at your Fingertips Blending and Segregation
Mechanisms for Solids This one-page reference provides
information on the common mechanisms by which mixtures of solids blend
and segregate
27
Feature Report Part 1 Scaling Industrial
Decarbonization with Advanced Membranes
The potential of membrane technology to unlock hybrid and scalable carbon
capture, combined with results from early field trials, suggest that advanced
membranes will play a crucial role in enabling more widespread adoption of
decarbonization strategies
31
12
27
Feature Report Part 2 Proton-Exchange
Membranes: Design Strategies for Water Electrolysis
Designing a proton-exchange membrane that will balance the efficiency,
durability and safety requirements for hydrogen production requires careful
consideration of materials and chemistry
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
1
34
Engineering Practice
Make the Most of Alarms
As processes have become more complex and dynamic, alarm management
software has evolved, and now provides deep intelligence to keep plant
personnel safer, more aware and more efficient
37
Environmental Manager Fire and Explosion Safety:
Going Beyond Traditional Protection A sophisticated
approach to fire and explosion safety requires one that expands conventional
protection strategies to comprehensively consider storage, containment and
tool compatibility
.Equipment and Services
34
16
Focus on Laboratory Equipment
Monitoring capabilities for shared laboratory spaces; A handheld device for
vacuum measurement tasks; This instrument simplifies water analysis; A
single device for measuring density and sound velocity; This system provides
automated decontamination; and more
37
20
New Products
Moisture measurements in hazardous environments; These dust-control fans
are now ATEX-certified; High-performance drive units with cybersecurity built
in; New screw conveyor offers flexibility and easy maintenance
.Departments
16
4
Editor’s Page AI’s potential in the CPI
Artificial intelligence (AI) holds great potential in the chemical process industries
(CPI), including hastening technological advances. Care, however, must be
taken in its adoption
44
Economic Indicators
Advertisers
41
42
42
43
Hot Products
Classified Ads
Subscription and Sales Representative Information
Ad Index
.Chemical Connections
Join the Chemical Engineering Magazine
LinkedIn Group
Visit us on www.chemengonline.com for more
articles, Latest News, New Products, Webinars, Test
your Knowledge Quizzes, Bookshelf and more
Coming in March
Cover design:
Tara Bekman
Cover image:
Shutterstock
2
Look for: Feature Reports on Industrial Control System Security; and Filtration;
A Focus on Performance Materials; A Facts at your Fingertips on Mass
Transfer; a Newsfront on High-Purity Process Equipment; New Products;
and much more
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
WHEN
QUALITY
MATTERS...
Pop-A-Plug® Tube Plugs
ASME PCC-2 Compliant Heat Exchanger Tube Plugging System
Trusted by chemical plants around the world as their go-to tube plugging solution, Pop-A-Plug Tube Plugs from Curtiss-Wright are
engineered for optimal performance throughout the life cycle of heat exchanger equipment. Simple hydraulic installation eliminates
welding and time-consuming heat treatments that can cause damage to tubes, tube sheet ligaments, and joints.
• No Welding Required
• Simple Hydraulic Installation
• Pressure Ratings Up to 7000 PsiG (483 BarG)
• Helium Leak Tight Seal to 1 x 10-10 cc/sec
• 100% Lot Tested to Ensure Unmatched Quality
• Wide Range of Sizes & ASME/ASTM Certified Materials Available
877.537.9120 l est-sales@curtisswright.com l cw-estgroup.com/che-25
For details visit adlinks.chemengonline.com/88111-02
Editor s Page
EDITORS
AUDIENCE
DEVELOPMENT
DOROTHY LOZOWSKI
JENNIFER McPHAIL
Editorial Director
dlozowski@chemengonline.com
Senior Marketing Manager
jmcphail@accessintel.com
SCOTT JENKINS
GEORGE SEVERINE
Senior Editor
sjenkins@chemengonline.com
Fulfillment Director
gseverine@accessintel.com
MARY PAGE BAILEY
DANIELLE ZABORSKI
Senior Editor
mbailey@chemengonline.com
List Sales: Merit Direct, (914) 368-1090
dzaborski@meritdirect.com
GROUP PUBLISHER
INFORMATION
SERVICES
MATTHEW GRANT
Vice President and Group Publisher,
Energy & Engineering Group
mattg@powermag.com
CHARLES SANDS
Director of Digital Development
csands@accessintel.com
ART & DESIGN
CONTRIBUTING EDITORS
TARA BEKMAN
JOY LEPREE (NEW JERSEY)
Senior Graphic Designer
tzaino@accessintel.com
jlepree@chemengonline.com
PRODUCTION
GEORGE SEVERINE
Production Manager
gseverine@accessintel.com
EDITORIAL ADVISORY BOARD
JOHN CARSON
JOHN HOLLMANN
DAVID DICKEY
HENRY KISTER
Jenike & Johanson, Inc.
Validation Estimating LLC
MixTech, Inc.
Fluor Corp.
HEADQUARTERS
40 Wall Street, 16th floor, New York, NY 10005, U.S.
Tel: 212-621-4900
Fax: 212-621-4694
EUROPEAN EDITORIAL OFFICES
Access Intelligence International
Postfach 20 01 39
D-63307 Roedermark
Tel: +49-172-6606303
CIRCULATION REQUESTS:
Tel: 800-777-5006
Fax: 301-309-3847
Chemical Engineering, 9211 Corporate Blvd.,
4th Floor, Rockville, MD 20850
email: clientservices@accessintel.com
ADVERTISING REQUESTS: SEE P. 42
CONTENT LICENSING
For all content licensing, permissions, reprints, or e-prints, please contact
Wright’s Media at accessintel@wrightsmedia.com or call (877) 652-5295
ACCESS INTELLIGENCE, LLC
HEATHER FARLEY
Chief Executive Officer
JOHN B. SUTTON
Chief Financial Officer
MACY L. FECTO
Chief People Officer
JENNIFER SCHWARTZ
Divisional President,
Industry & Infrastructure
LORI JENKS
Senior Vice President,
Event Operations
DANIEL J. MEYER
Senior Vice President,
Corporate Controller
MICHAEL KRAUS
Vice President,
Production, Digital Media & Design
JONATHAN RAY
Vice President, Digital
TINA GARRITY
Vice President of Finance
MICHELLE LEVY
Vice President,
Administration
9211 Corporate Blvd., 4th Floor
Rockville, MD 20850-3240
www.accessintel.com
4
AI’s potential in the CPI
O
ne of the aspects of my job that I really enjoy is keeping in
touch with new and advanced technologies emerging from
the chemical process industries (CPI) — an interest that
traces back to my roots as an R&D engineer. Since products from the CPI are used in just about every facet of our lives, the
technologies being developed and scaled up are as varied as the intended applications, and many have far-reaching implications. Need,
economics and resource availability are some of the factors that influence how quickly specific technical developments progress. And, automation plays an increasingly important role in these advances — in
process and product development, scale up and manufacturing. Developments in smart sensors and digitalization have already greatly influenced many manufacturing sectors, including the CPI. Now, focus
is largely on artificial intelligence (AI), whereby vast data resources are
being harnessed to effect faster and more-advanced outcomes.
AI is a rather broad category of technologies that allow computers to
simulate human abilities related to learning, problem solving and creativity. Machine learning (ML) and generative AI (Gen AI) fall under its umbrella. In ML, computers make predictions based on data that they have
“learned.” The more-advanced Gen AI — made popular, for example,
by ChatGPT — enables a computer to generate new work that is similar,
but not the same as the data it has learned from. The increased use of AI
is one of the leading drivers in the growing demand for semiconductors,
and the chemicals that are used in their production.
Use of AI in the CPI is expanding. One of the better-known applications in manufacturing is predictive maintenance. Additional applications range from technical process and product developments to
business applications like supply-chain management [1]. One practical
example mentioned in this month’s article “Make the Most of Alarms”
(pp. 34–36) is the incorporation of AI in alarm-management software to
help with operational safety and efficiency. Last month’s issue describes
how AI is accelerating the development of advanced materials [2].
The capabilities of AI and its possible applications in the CPI are
many. It may help in designing more efficient catalysts and speed up
R&D. AI integrated with robotics, for example, is being explored as a
way to expedite discoveries in chemical synthesis [3]. New technological advances are bound to be hastened as advanced automation
tools are implemented.
While AI undoubtedly holds great potentiaI, there are also concerns.
A study of 3,000 researchers and clinicians [4] revealed that over 90%
of those surveyed agreed that AI will help accelerate knowledge and
discovery, rapidly increase the volume of research conducted and
offer cost savings. Over 90%, however, were also concerned that AI
would be used for misinformation and about 85% were concerned
that AI would lead to weakened critical thinking.
AI is a powerful tool that offers exciting possibilities, but care is
needed in its adoption. As Kieran West, executive vice president,
Strategy, at Elsevier, said in a press release about
the study: “. . . high quality, verified information, responsible development and transparency are paramount to building trust in AI tools ...”
■
Dorothy Lozowski, Editorial Director
1. Bailey, M., Artificial Intelligence: Advancing Applications in the CPI,
Chem. Eng., June 2021, pp. 12–18.
2. Jenkins, S., Accelerating Materials Development with AI, Chem. Eng.,
January 2025, p. 18.
3. Ondrey, G., Autonomous synthesis robot uses AI to speed up chemical
discovery, Chem. Eng., March 2024, p. 8.
4. Elsevier, Insights 2024: Attitudes toward AI, July 2024, www.elsevier.
com/insights/attitudes-toward-ai.
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Chementator
Edited by: Dorothy Lozowski
Carbon-neutral calcium carbonate process uses emissions
from steel-making plant
C
onstruction is imminent for a carbon-capture
project aimed at reducing CO2 emissions from
steel production while producing carbon-neutral
calcium carbonate. At the U.S. Steel (Pittsburgh,
Pa.; www.ussteel.com) manufacturing facility in Gary, Ind.,
a carbon-capture system designed by CarbonFree (San
Antonio, Tex.; www.carbonfree.cc) will capture CO2 emissions from the fluegas of the steel plant and convert it into
powdered calcium carbonate for a wide range of applications, including as a component in paints, coatings and
adhesives, as well as food, plastics and others.
CarbonFree has developed a process, known as SkyCycle™, to convert exhaust CO2 into high-purity CaCO3.
The process works by contacting the flue gas with a magnesium hydroxide solution that captures the CO2 as magnesium bicarbonate (diagram). The magnesium bicarbonate is reacted
with CaCl2 derived from calcium-containing
slag onsite, allowing the product CaCO3 to
precipitate
out
Carbon Free
of solution. Slag is a byproduct of the blast-furnace steel
process that contains a mix of metal oxides. The process
also involves recovering MgCl2 from the reaction that produces the CaCO3 product and heating it to decompose it
into MgOH and HCl, which are then used in another cycle
of the process. Treating the slag with HCl can produce the
required CaCl2.
“We use LeChatelier’s principle of chemical equilibrium
to drive the reactions in the cycle,” explains Bill Bryant,
marketing director at CarbonFree. “Instead of talking
about the cost of carbon required for carbon capture,
this approach allows us to talk about lowering the carbon
footprint of our customers’ products, while making a sustainable and profitable business.”
The carbon-neutral CaCO3 product, known as endurocal®, was launched in November 2024, and Bryant says
pilot-scale samples of the product are available for applications testing from the company’s demonstration plant
at Southwest Research Institute (SwRI; San Antonio, Tex.;
www.swri.org).
CarbonFree says endurocal has the same properties as
conventionally produced precipitated calcium carbonate
(PCC), in terms of particle shape, particle size distribution
and purity, but with a lower cost and zero carbon footprint.
New sustainable materials from recycled carbon nanotubes
R
ecycling materials, such as plastics and metals,
is an attractive, but challenging path toward sustainable material manufacture. Now, researchers
have made a discovery that may have far-reaching implications in material manufacture by positioning
carbon nanotube (CNT) fibers as a sustainable alternative
to metals, polymers and much larger carbon fibers.
Researchers at Rice University (Houston, Tex.; www.
rice.edu) have demonstrated that CNT fibers can be recycled without structural or property losses, and more
readily than some more-difficult-to-recycle materials.
“Recycling has long been a challenge in the materials
industry — metals recycling is often inefficient and energy
intensive, polymers tend to lose their properties after reprocessing and carbon fibers cannot be recycled at all,
only downcycled by chopping them up into short pieces,”
said Matteo Pasquali, director of Rice’s Carbon Hub
(carbonhub.rice.edu) and the A.J. Hartsook Professor of
Chemical and Biomolecular Engineering, Materials Science and NanoEngineering and Chemistry. “We expected
that recycling would be difficult and would lead to significant loss of properties. Surprisingly, we found that carbon
nanotube fibers far exceed the recyclability potential of existing engineered materials, offering a solution to a major
environmental issue.”
In this research, solution-spun CNT fibers were created
by dissolving fiber-grade commercial CNTs in chlorosulfonic acid. To simulate recycling of a variety of materials,
fibers made from different types of CNTs produced by different manufacturers were initially processed into separate single-source virgin fibers, then recycled by combining them and mixing in chlorosulfonic acid. Surprisingly,
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
mixing the two fibers led
to complete redissolution
and no sign of separation
of the two source materials
into different liquid phases.
This redissolved material
was spun into a mixedJeff Fitlow/Rice University
source recycled fiber that
retained the same structure and alignment of the virgin
fiber. Some materials degrade in quality during recycling,
but the CNT fibers retained 100% of their original properties after recycling.
“The ability to fully recycle CNT fibers has broad implications for industries like aerospace, automotive and electronics,” said Michelle Durán-Chaves, a graduate student
in chemistry. “We hope this could pave the way for fully
recyclable composites in aircraft, vehicles, civil infrastructures and more, ultimately reducing environmental impacts across a wide range of sectors.”
This research is part of the broader program of the Carbon Hub, a Rice-led initiative developing a zero-emissions
future, where advanced carbon materials and clean hydrogen are co-produced efficiently and sustainably from
hydrocarbons. The work was published in the journal Carbon, and was supported by the Department of Energy’s
Advanced Research Project Agency, the Air Force Office
of Scientific Research, the Robert A. Welch Foundation,
the National Science Foundation, the Novo Nordisk Foundation CO2 Research Center, the Ken Kennedy Institute
Graduate Fellowship from Schlumberger and Rice and a
Riki Kobayashi Fellowship from Rice’s chemical and biomolecular engineering department.
FEBRUARY 2025
5
Deepwater RO could cut energy use and environmental impact
of seawater desalination
D
esalination of seawater with reverse osmosis
(RO) membranes is a key technology for addressing water scarcity issues around the globe,
but seawater desalination is energy-intensive
and the brine discharge can create coastal environmental problems. The company Flocean AS (Oslo, Norway;
www.flocean.green) is among a handful of companies
developing technology for deepwater RO desalination,
an approach that has a number of cost and operational
advantages over conventional seawater RO.
“Terrestrial seawater RO requires high pressures and
is susceptible to bio-fouling of the membranes, as well
as negative environmental impacts associated with
chemical pre-treatment of seawater and discharge of
concentrated brine,” explains Alexander Fuglesang,
CEO of Flocean. Deepsea RO takes advantage of the
high surrounding hydrostatic pressures, which align
with the osmotic pressure needed for desalination. This
reduces the energy required
to push water through the
membranes by 30 to 50%
compared to land-based RO,
Flocean says.
Installation in deep water
also allows the high-pressure
pump to be placed downstream of the RO membranes, on the permeate side, drawing water over the
membranes rather than pushing it through (diagram).
This means energy is focused only on the product
water, unlike in terrestrial seawater RO plants, where
energy is used to pressurize the entire feed stream, the
company states.
In addition to the energy savings, the water properties
at depths of 400–600 m offer considerable advantages
for RO. “Seawater at that depth contains minimal algae,
so pre-treatment requirements are reduced, and the temperature, pressure and salinity are much more consistent
than surface water, which has operational advantages,”
Fuglesang remarks.
Further, because of the energy and operational advantages, deepwater RO can be economically feasible at
much lower recovery rates than conventional RO (10–
20% water recovery with deepsea, versus 40–50% for
conventional). This alleviates many of environmental impacts of the brine discharge, as well as reducing biofouling and scale formation
Flocean has its origins in a Norwegian company with
expertise in building and installing deepsea pumping
systems for the offshore oil and gas sector. The ideas
and concepts for deepwater RO have been around
since the late 1990s, but
with costs of underwater
robotics coming down, and
water scarcity issues growing, it makes more sense
now, Fuglesang explains.
Flocean
recently
announced a new round of
Flocean
investment that will further
construction of a demonstration plant on the west coast
of Norway. The company plans to start up the facility in
early 2026. Fuglesang says his company is currently negotiating commercial “water-as-a-service” contracts for
clients in the Mediterranean Sea and Red Sea regions.
On-demand ammonia production from atmospheric air
N
early all ammonia is produced using methane
via the Haber-Bosch process, which requires
high-temperature and high-pressure operation. A new portable prototype device developed by researchers from Stanford University (Stanford,
Calif.; www.stanford.edu) and King Fahd University of
Petroleum and Minerals (Dhahran, Saudi Arabia; www.
kfupm.edu.sa) has demonstrated the production of ammonia from ambient air without any external electricity or
radiation source.
Using wind as its motive force, air is drawn through
a special catalyst mesh consisting of magnetite (Fe3O4)
and Nafion fluoropolymer. Capturing nitrogen from the
air and hydrogen from water-vapor microdroplets, the
catalyst-mesh structure facilitates the reaction to form
an ammonia-rich aqueous solution within the device.
This solution is collected by a condenser plate to separate it from any unreacted air or water vapor in the reaction chamber. The performance of the device depends
on many environmental factors, such as humidity and
wind speed, as well as the size, salt content and acidity
of the water droplets. The researchers tested the de6
vice in the field at nine different locations in California’s
Bay Area to verify its performance over a wide range of
relative humidities, temperatures and wind speeds. The
device has demonstrated its ability to produce ammonia
solution of sufficient concentration (25 to 120 μM in 1
hour, depending on local relative humidity) for use as a
hydroponic fertilizer.
Other properties that were tuned to improve ammonia synthesis included the pore size of the mesh and
the size distribution of water microdroplets entering the
chamber. Larger pore sizes led to less-effective catalytic
interaction, while pores that were too small condensed
the gas and water before they could pass through the
mesh and react.
The ability to generate ammonia onsite for fertilizer applications is extremely beneficial, as it eliminates the need
for storing and transporting materials. The researchers
hope that the device could eventually be integrated with
irrigation systems, enabling localized, on-demand ammonia production for agricultural sites. They are currently
working to expand the mesh-system size to produce
larger volumes of ammonia.
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Made for your blending process
ROSS Ribbon Blenders meet the toughest
requirements for quality materials and heavy-duty
construction. Standard features include thick stainless
steel troughs, low-maintenance gearmotors, strong
double-helical ribbon design and much more.
Need a Ribbon Blender customized for your process?
ROSS offers MANY options. Complete control
systems, spray nozzles for coating, pressure feed
vessels and vacuum operation, to name a few.
Used in a wide range of applications, from
powders, granules and other bulk solids, to light
pastes and slurries, ROSS Ribbon Blenders may be
customized to meet your manufacturing goals.
Sizes from ½ cu. ft. to 1000 cu. ft. A variety of
standard models are in stock for faster delivery.
Available worldwide.
mixers.com/ribbon-blenders
mixers.com
For details visit adlinks.chemengonline.com/88111-03
1-800-243-ROSS
Pilot project planned for thermocatalytic ethanol-tobutene process
I
n December 2024, the Pacific Northwest National
Laboratory (PNNL; Richland, Wash.; www.pnnl.gov)
announced a three-year collaborative project with vehicle-tire manufacturer Bridgestone (Tokyo, Japan; www.
bridgestone.com) to scale up a thermocatalytic process
for converting renewably derived ethanol to n-butene.
Conventionally, n-butene is produced from petroleumbased feedstocks using energy-intensive cracking of
large hydrocarbons. The PNNL process, using a catalyst
PNNL researchers first conceived in 2018, could lower
the energy requirements for n-butene production compared to the conventional process, and allow the use
of renewably derived n-butene as a starting material for
multiple commercial processes, including those for tires
(styrene-butadiene), as well as other synthetic rubbers,
plastics and diesel and jet fuels.
After advancing the catalyst over the past few years,
PNNL partnered with Bridgestone to scale up and pilot
the catalysis process using $10 million in funding from
the U.S. Dept. of Energy’s Industrial Efficiency and Decarbonization Office. Bridgestone plans to build a pilot
plant for the process in Akron, Ohio.
The PNNL catalytic process has shown the ability to
convert ethanol to n-butene at high rates and with high
yields. A highly active, multifunctional catalyst comprising
silica as a support material, with silver nitrate powder and
zirconium nitrate as the catalytic material, enables a sin-
gle-step conv e r s i o n
process (diagram).
The
catalyst,
together
with
the process,
generates nbutene
with
greater than
PNNL
90% ethanol
conversion and greater than 60% selectivity (byproducts
are predominantly other olefins), PNNL says.
The process works by removing hydrogen from ethanol molecules, creating acetaldehyde. Formation of carbon-carbon bonds follows to produce crotonaldehyde,
which occurs in a variety of foods, like soybean oils. The
crotonaldehyde is then converted to crotyl alcohol, which
undergoes dehydration, resulting in butadiene. Butadiene then is selectively hydrogenated to n-butene. A more
recent catalyst formulation produces n-butene through
butyraldehyde instead of butadiene intermediate, PNNL
says. This new catalyst formulation produces three times
less coke, leading to significantly improved catalyst stability, PNNL says.
Catalyst regeneration has been demonstrated, the
laboratory adds. The technology is available for licensing.
Single-step process for electrified ethylene production
D
eveloping sustainable pathways to ethylene —
among the world’s most widely used chemicals
— is a key element in decarbonizing the process
industries. A new electrolysis technology developed by CERT Systems (Toronto, Ont., Canada; www.
co2cert.com) can produce ethylene from CO2 and water,
splitting the CO2 molecule and reforming it into ethylene
using renewable energy (diagram). “Our Direct CO2 Electrolysis technology is the only single-step process to generate sustainable ethylene. Other processes to convert
CO2 into ethylene require a separate source of hydrogen
or an intermediate feedstock, such as syngas or ethanol.
Our process only requires CO2 and water as reactants, reducing complexity and cost,” explains Alex Ip, co-founder
and CEO of CERT Systems. Similar to the production of
“green” hydrogen via water electrolysis, the process depends on a membrane electrode assembly and an electrocatalyst to facilitate the ethylene and oxygen evolution
reactions. Unlike most water-electrolysis systems, notes
Ip, CERT’s catalysts do not require any precious metals.
CERT’s technology is designed to be agnostic to the
source of CO2, meaning that industrial emissions or atmospheric CO2 can be successfully converted into ethylene. The process’ emissions-processing performance
was first demonstrated in the field at Shepard Energy
Centre natural-gas power plant in Calgary, Alta., Canada.
“This was the first time that industrial emissions had been
converted into ethylene. We were able to convert up to
100 kg of CO2 per day in this project,” says Ip. The company recently began a research partnership with global
8
chemicals manufacturer AGC, Inc. (Tokyo, Japan; www.
agc.com) to further develop the technology for commercial use. “AGC is seeking ways to convert their process
emissions into feedstocks that they currently need to
buy, including ethylene. Our technology can help reduce
their emissions while generating their own feedstocks internally,” adds Ip.
CERT Systems
The next steps in scaling the technology will be to expand the system’s range of tolerance for different feed
compositions and moving to a commercial-scale pilot
plant following funding. Beyond decarbonizing ethylenebased processes, the company plans to apply its technology to other chemical pathways, such as the production of sustainable aviation fuel (SAF).
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Flow chemistry yields a more sustainable route to isocyanates
T
he wide range of performance properties of polyurethane foams makes them essential in many
consumer goods. Thus, there is much effort going
into creating a more environmentally friendly production process for polyurethane’s main building blocks,
polyols and isocyanates. While much progress has been
made across the industry to develop bio-based routes to
different polyols, developing new technologies for isocyanates has proven more elusive, due in part to the presence of highly toxic phosgene and hydrochloric acid in
conventional petroleum-derived isocyanates production.
Now, a novel flow-chemistry approach is being demonstrated to enable a biological production pathway for isocyanates, while avoiding risks associated with phosgene.
Algenesis Materials’ (San Diego, Calif.; www.
algenesislabs.com) patented technology, originally developed in the laboratory of chemistry professor Michael
Burkart at the University of California San Diego (www.
ucsd.edu), converts algae-based fatty acids into isocyanates via acyl azides in a continuous-flow process. “Using
flow chemistry, we never accumulate large amounts of
any of the hazardous intermediates. We go right from the
precursor, which is a hydrazine, to the diisocyanate in
flow,” explains Stephen Mayfield, chief executive officer
of Algenesis. The group has used this method to make
some 25 different types of isocyanates, including some
that are very similar in structure and properties to toluene
diisocyanate (TDI) and methylene diphenyl diisocyanate
(MDI), which are widely used in polyurethane foams.
A benefit of the bio-based isocyanates pathway is that
it can provide “different physical properties to the ultimate
polyurethane — lower carbon footprint, novel properties
and biodegradability — than conventional fossil-based
isocyanates, says Mayfield. “What’s unique about our
foams is high biological content, while meeting performance specifications like rebound and tensile strength.
And we are moving toward cost parity for certain consumer applications — the benefit of algae is they grow
quickly and relatively cheaply,” he adds. In combination
with the company’s already-established bio-based polyols production process, Algenesis’ renewable and biodegradable polyurethane materials have been utilized in
footwear, phone cases and more.
Currently, Algenesis produces several kilograms per
week of renewable isocyanates, and work is ongoing to
scale up to 2 ton/yr in 2025. The company has also
received a grant from the U.S. Department of Defense to
evaluate plans for a 10-ton/yr facility.
Creating ultrathin gold films with the largest continuous area
T
hin gold films offer a broad range of benefits for
electronics due to their high electrical conductivity and transparency. Current manufacturing
methods are unable to achieve gold films thinner
than 10 nm, and are also limited in the area and continuity of films they can produce, due to the formation
of “metal islands” — clusters of atoms on the substrate
that can hinder conductivity, mechanical stability and
substrate coverage. A new high-vacuum deposition
process that takes inspiration from the chemical vapor
deposition of graphene, developed in a collaboration between Xpanceo (Dubai, U.A.E.; www.xpanceo.com) and
professor Konstantin S. Novoselov from the University of
Manchester (U.K.; www.manchester.ac.uk), overcomes
these challenges, producing films as thin as 3.5 nm with
continuous, unrestricted area — moving a step closer to
atomically thin gold films.
“We developed a graphene-based method for synthesizing transferable, wafer-scale ultrathin gold films with
exceptional conductivity and transparency. These new
films are ideal for applications like flexible electrodes,
biosensing and thermal management. Unlike traditional
methods, our approach avoids percolation issues and
enables new study techniques to be used on atomically
thin metals, such as plasmonics. This work marks a milestone whereby two-dimensional (2-D) fabrication techniques start making their way into the domain of conventional 3-D materials,” says Valentyn Volkov, Xpanceo
co-founder and chief technology officer.
Using traditional production techniques, gold atoms
are evaporated within a vacuum chamber until they form
clusters on the substrate that then merge into a continuous film around 10–20-nm thick. If they are any thinner,
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
they lack continuous morphology. With
X p a n c e o ’s
new method,
gold films are
deposited
onto a copper substrate
(which itself
is deposited
onto a silicon/
graphene
substrate) and
coated with
polymethyl
methacrylate
Nano Lett
(PMMA). The
PMMA/Au/Cu structure then undergoes electrochemical
delamination from the silicon/graphene layer in potassium chloride solution, followed by dissolution of the Cu
layer and cleaning, resulting in a free-standing PMMA/Au
film (diagram; source: Nano Lett. 2024, 24, 51, 16,270–
16,275). “These films feature continuous structures and
can be transferred to any substrate via electrochemical
techniques. The films maintain their conductivity under
extreme bending and offer balance between transmittance and conductivity,” explains Volkov.
According to Volkov, the method allows for the scalable production of 2-D metallic films greater than 1 m2 in
area using established roll-to-roll techniques — a significant improvement over current 2-D gold films, which are
typically no more than 0.000001 mm2.
■
FEBRUARY 2025
9
Business News
LINEUP
AGC
ASHLAND
BASF
BAYER
CALGON CARBON
COVESTRO
FUJIFILM
IMERYS
MESSER
MITSUBISHI CHEMICAL
MITSUI CHEMICALS
MOSAIC
PHILLIPS 66
SIEMENS
WOOD
Look for more
latest news on
chemengonline.com
10
Plant Watch
Messer to construct $70-million
air-separation unit in Arkansas
January 15, 2025 — Messer Group GmbH
(Bad Soden, Germany; www.messergroup.
com) has announced a strategic investment of
over $70 million to construct a state-of-the-art
air separation unit (ASU) in Berryville, Ark. This
new ASU will also complement the company’s
existing facility in Lewisville, Ark., enhancing
production capacity for various gases. The
ASU in Berryville is slated for completion in
the second half of 2026.
begin in 2025, with operations starting by
the end of 2026.
Messer Group starts up
“green” CO2 plant
January 2, 2025 — Messer Group has begun
operations at a new plant producing “green”
CO2 at its Vrdy site in the Czech Republic. At
this site, Messer sources the CO2 as raw gas
from a local bioethanol producer, reducing
greenhouse gases emissions and lowering
the dependency on fossil-based sources.
Mitsubishi Chemical targets batteries,
semiconductors with expansion projects
January 2, 2025 — The Mitsubishi Chemical
Group (MCG; Tokyo; www.mcgc.com) has
announced two capacity expansions at
its production sites in Japan. In the first
project, MCG will increase its production
capacity for synthetic silica powder used in
semiconductor manufacturing at its KyushuFukuoka plant. Operations are scheduled to
start in September 2028, with a 35% increase
over current production capacity. The second
expansion focuses on anode materials for
lithium-ion batteries at MCG’s Kagawa Plant,
with the expanded operations scheduled to
start in October 2026. The expansion should
AGC invests in a new glass
increase production capacity at the site to
production line in Lodelinsart, Belgium
January 14, 2025 — AGC Glass Europe, the 11,000 metric tons per year (m.t./yr).
European branch of AGC Inc. (Tokyo; www.
agc.com), announced a major investment in Mergers & Acquisitions
a new insulating vacuum-glass production Bayer acquires biofuel feedstock
line at its Lodelinsart site in Belgium. The new assets from Canadian firm
production line is scheduled to start operations January 15, 2025 — Bayer AG (Leverkusen,
Germany; www.bayer.com) announced that it
in 2026.
has acquired assets from Canada-based Smart
Earth Camelina Corp. to expand its position
Fujifilm Diosynth Biotechnologies
in biomass-based feedstock markets. The
expands production site in Denmark
January 13, 2025 — Fujifilm Diosynth acquired assets include intellectual property
Biotechnologies, a group company of Fujifilm and materials assets related to camelina
Corp. (Tokyo; www.fujufilm.com), completed germplasm. Camelina is a novel intermediate
its recent production expansion in Hillerød, oilseed crop with a promising low-carbon
Denmark. This first expansion at the site intensity for renewable fuel production. Bayer
increases capacity from six to twelve bioreactors also recently announced a partnership with
for mammalian cell culture, making the site Neste Corp. (Espoo, Finland; www.neste.com)
the largest end-to-end biopharmaceutical to develop canola-based biofuel feedstocks
in the southern U.S.
manufacturing site in Europe.
Mitsui Chemicals to expand production
capacity for ophthalmic lens materials
January 15, 2025 — Mitsui Chemicals, Inc.
(Tokyo; www.mitsuichemicals.com) plans to
boost production capacity for its MR series of
high-refractive-index lens material by building
a second MR plant at its Omuta Works site
in Japan. MR is a thiourethane-based highrefractive-index lens material that offers a high
Abbe value (minimizing chromatic aberration)
and high refractive index, while being lightweight
and impact-resistant. The new plant is slated
to begin commercial operation in 2028.
Covestro to expand
polycarbonate production site in Ohio
January 8, 2025 — Covestro AG (Leverkusen,
Germany; www.covestro.com) plans to
expand its site in Hebron, Ohio, where it will
construct multiple new production lines and
infrastructure to manufacture customized
polycarbonate compounds and blends.
This project will significantly expand the
capacity of Covestro’s Solutions & Specialties
business for the U.S. market. Construction
of the new production lines is scheduled to
CHEMICAL ENGINEERING
Mosaic to sell phosphate mining unit
in Brazil to Fosfatados Centro
January 15, 2025 — The Mosaic Co. (Tampa,
Fla.; www.mosaicco.com) and Fosfatados
Centro SPE Ltda. announced that they have
entered into an agreement for the sale of a
phosphate asset owned by Mosaic located in
Patos de Minas, Brazil. Upon the closing of the
transaction, Fosfatados Centro will assume
responsibility for the Patos de Minas mine and
tailings dams, and pay Mosaic $125 million
over six years.
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Ashland sells Avoca
business line to Mane
January 9, 2025 — Ashland Global
Holdings Inc. (Wilmington, Del.;
www.ashland.com) agreed to sell
its Avoca business to Mane S.A. (Le
Bar-sur-Loup, France; www.mane.
com), a global producer and supplier
of fragrances and flavors. Ashland’s
Avoca business supplies Sclareolide, a
fragrance fixative, and operates a range
of contract manufacturing capabilities
from two production facilities in North
Carolina and Wisconsin.
BASF to sell Styrodur
insulation materials business
January 9, 2025 — BASF SE
(Ludwigshafen, Germany) has signed
an agreement for the sale of its
Styrodur business line to insulation
material manufacturer Karl Bachl
Kunststoffverarbeitung GmbH & Co.
KG (Röhrnbach, Germany). Styrodur
is an insulation material made from
extruded polystyrene (XPS). The
completion of the sale is expected
by mid-2025, subject to the approval
of relevant competition authorities.
Phillips 66 announces
$2.2-billion EPIC NGL acquisition
January 7, 2025 — Phillips 66, Inc.
(Houston, Tex.; www.phillips66.com)
entered into a definitive agreement
to buy EPIC Y-Grade GP, LLC and
EPIC Y-Grade, LP, which own various
subsidiaries and long-haul natural gas
liquids (NGL) pipelines, fractionation
facilities and distribution systems (EPIC
NGL), for a total cash consideration of
$2.2 billion. The EPIC NGL business
consists of two fractionators near Corpus
Christi, Tex., approximately 350 miles
of purity-distribution pipeline and an
approximately 885-mile NGL pipeline.
Imerys completes acquisition of
Chemviron business in Europe
January 7, 2025 — Imerys S.A. (Paris;
www.imerys.com) has acquired the
European diatomite and perlite assetw
of Chemviron, a subsidiary of Calgon
Carbon Corp. (Moon Township, Pa.;
www.calgoncarbon.com). In 2024, this
business generated around €50 million
in revenue. With this transaction, Imerys
acquires three mining and industrial
assets in France and in Italy.
Wood completes sale of Ethos
Energy stake for $138 million
January 3, 2025 — John Wood Group
PLC (Wood; Aberdeen, U.K.; www.
woodplc.com) has completed the sale
of its stake in Ethos Energy Group Ltd.,
a joint venture (JV) focused on rotating
equipment, to One Equity Partners
for $138 million. Wood owned 51% of
the Ethos Energy joint venture with its
partner, Siemens Energy AG (Munich,
Germany; www.siemens.com).
BASF sells food and health
ingredients business
January 2, 2025 — BASF agreed to
sell its Food and Health Performance
Ingredients business, including the
production site in Illertissen, Germany,
to Louis Dreyfus Co. (LDC), a global
processor of plant-based ingredients.
The acquired business comprises
numerous product lines, including
aeration and whipping agents, food
emulsifiers, fat powder grades, plant
sterol esters, conjugated linoleic acid
(CLA), omega-3 oils for human nutrition
and some smaller product lines. ■
Mary Page Bailey
Imagine the Possibilities
Ultrapen PTBT Series
Compatible with Android
and iOS Devices.
Ultrameter ll
TM
E
Conductivity
Resistivity
TDS
ORP/Free Chlorine Equivalent (FC E TM)
pH
Temperature
www.myronl.com
760-438-2021
For details visit adlinks.chemengonline.com/88111-04
Newsfront
Heat Exchange Solutions
Support Sustainability
Developments in heat exchange technologies promote efficiency, reliability and
cost effectiveness
H
eat exchange technologies play a pivotal role in
industrial sustainability efforts because they are
at the forefront of enabling more
environmentally friendly chemical
processes, while also serving as a
core mechanism in evolving clean
technology and electrification projects. However, to find success in
traditional or developing applications, selection of the right heat exchange technology is essential, as
it will provide more energy-efficient
performance, greater reliability and
lower operational costs. Fortunately,
innovative heat-exchange solutions
are available to suit every industry
need and overcome common process challenges in both existing and
emerging applications.
“Chemical processing companies
Source: HRS
FIGURE 1. HRS Heat Exchangers’ corrugated tube
design provides a number of benefits over smooth
tube designs
12
are concerned about their carbon
footprint, which is directly related
to the energy efficiency of their processes and hence, to their heat exchangers,” says Alasdair Maciver,
head of energy storage solutions and
vice president of the welded heat
exchangers business unit, with Alfa
Laval (Lund, Sweden; alfalaval.com).
“At the same time, the ‘clean-tech’
space is looking at new, innovative
processes in hydrogen, carbon capture and energy storage and these
efforts come with new demands for
heat exchangers.”
According to the experts, moreefficient heat transfer, increased reliability and more cost-effective operation are of the highest priority for
today’s heat exchange technologies,
no matter the application.
“Chemical processors are looking
for heat exchange systems that meet
high standards around performance
and reliability, tempered against a reasonable cost of investment,” explains
Warren Chung, regional director with
Solex Thermal Science (Calgary,
Alta., Canada; solexthermal.com).
“As operators seek to maximize the
useful operating life of their facilities,
they have been increasingly considering heat exchange options from the
total cost of ownership perspective
rather than simply the lowest upfront
capital investment. Operators have
realized that production disruptions
due to failed or underperforming
heat exchange systems are significantly costlier than investing in higher
quality heat exchange systems with
greater longevity.”
“However, the challenge is determining which technology works best
for your application and process
given the chemicals that will be flowCHEMICAL ENGINEERING
ing through it and the reaction,” adds
Nathan Thomson, manager business engineers with SWEP (Duluth,
Ga.; swep.net). “Operators need
an understanding of the innovation around the core heat exchange
technologies as they are constantly
evolving and each has its own advantages and disadvantages, depending on the application.”
Heat exchange innovations
While selecting the appropriate heat
exchange technology depends on
the specifications of the application,
developments and technologies that
focus on improving efficiency and
reliability often result in greater cost
effectiveness in any operation.
“Many of the challenges associated
with heat exchange technologies are
the same as in other sectors, although preventing unwanted chemical reactions, corrosion and fouling
are key considerations for chemical
processors, as they impact reliability and efficiency,” notes Matt Hale,
global key account director with HRS
Heat Exchangers (Marietta, Ga.; hrsheatexchangers.com). “But these
can be mitigated with appropriate
design and construction, depending
on each individual project. For example, the use of corrosion-resistant
stainless steel and corrugated-tube
architecture can minimize and prevent fouling (Figure 1).
“Such steps will also help maximize
heat transference and energy efficiency. For example, corrugated tubes
are more efficient than smooth tubes
in operation. As in all sectors, costs
are also a key consideration, although
it’s important to look at both capital
and operational costs, as a cheaper
installation may be more costly in the
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
long run, as it may require more heat
for ongoing operations.”
Hale says that HRS’s corrugatedtube technology provides a number of benefits when compared
to smooth tubes. “The first is that
corrugations create turbulent flow
in the product, helping to prevent
fouling. In turn, this improved efficiency means that corrugated tubes
provide greater levels of heat transfer than smooth tubes of the same
length, so corrugated-tube heat exchangers can be up to half the size
of their smooth tube equivalents.
The turbulence created in the tube
also reduces cleaning frequency and
simplifies maintenance compared to
other heat exchanger designs.”
Meanwhile, Alfa Laval’s Maciver
notes that transitioning from shelland-tube technology to more efficient plate-type heat exchangers,
where applicable, can help reduce
energy requirements and, consequently, a facility’s carbon footprint
and operational costs. “It’s a first,
and easy step on the journey to decarbonization and it provides several
additional benefits to chemical processes,” notes Maciver.
Because plate heat exchangers
have a smaller footprint, they are
easier to install, service and maintain. Plate technology also increases
reliability by reducing fouling, stress,
wear and corrosion to result in better
performance and longer operational
uptime. Additionally, the technology
minimizes energy costs and emissions, contributing to an improved
bottom line.
As an example of the benefits that
can be achieved, Maciver points to
a collaboration between Alfa Laval
and Dow Chemical (Midland, Mich.;
www.dow.com), in which a number
of heat exchanger positions at different sites were upgraded to improve sustainability and profitability.
Specifically, in a project at a Dow
site in Terneuzen, the Netherlands,
the existing shell-and-tube solution
used in a heat recovery role in the
ethylene oxide plant was replaced
with two Alfa Laval Compabloc heat
exchangers to achieve substantial
energy savings and reduced CO2
emissions. The replacement also
mitigated severe fouling problems,
CHEMICAL ENGINEERING
which increased uptime and improved product yield.
Also aimed at increasing efficiency,
Roy Niekerk, director of application
engineering at Kelvion GmbH (Monzingen, Germany; kelvion.com), explains his company’s offerings: “The
challenge given by our customers
is to have an as-close-as-possible
temperature approach in their heat
exchangers, which is often achieved
by a fully welded plate heat exchanger, such as the K°Flex, which
is a high-performance plate heat
exchanger designed for optimal flexibility and efficiency in heat transfer
applications (Figure 2).
“It features a modular design that
enables easy customization to suit
specific operational requirements,”
Niekerk continues. “The system offers efficient heat exchange, compact size and simplified maintenance,
making it ideal for industries such
as chemical processing and power
generation. Its robust construction
and adaptability enhance energy efficiency and operational sustainability.”
And, as an alternative solution
to increase reliability in difficult-tohandle process streams that are incompatible with traditional heat exchangers, Solex’s Chung suggests
the use of heat-pipe heat exchanger
(HPHE) solutions from Econotherm,
a Solex Thermal Science company
(Figure 3). “HPHEs reduce the risks
and the consequences of failure that
commonly plague traditional heat
exchanger types through the inclusion of multiple redundancies in the
heat exchanger design,” he says.
“By using HPHEs, operators realize fewer process disruptions and
longer run lengths without having to
sacrifice performance, especially in
particulate-rich and corrosive process streams.
“Due to the technical limitations of
traditional exchanger types, these
process streams were previously
inaccessible from a heat-recovery
perspective and otherwise considered wasted,” Chung explains.
“However, HPHEs now enable
chemical processors to unlock incremental energy-recovery opportunities within their operations and
present a viable solution for meeting
the evolving challenges.”
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Source: Kelvion
FIGURE 2. Kelvion’s K°Flex high-performance
plate heat exchanger features a modular design
that enables easy customization to suit specific
operational requirements. Its robust construction
and adaptability enhance energy efficiency and
operational sustainability
He points to the use of an HPHE
developed by Econotherm for use
as an air preheater in a petrochemical complex. “The application had
a failed plate-style recuperator that
needed to be replaced. The heat
exchanger outage was causing the
consumption of significantly higher
fuel quantities at the gas-powered
burners with increased associated
emissions,” he says.
“A HPHE unit was custom built
to match the complicated dimensioning of the existing unit, which
minimized capital investments in fan/
duct work. The HPHE was used to
cool the fluegas to near the acid-gas
dewpoint, enabling incremental heat
recovery from the primary stream of
corrosive fluegas, while minimizing
corrosion risk and lowering fuel consumption to below the requirements
from when the plate-style recuperator was in operation.”
Additionally, developments in heatexchanger coating technologies can
also provide a cost-effective means
of managing corrosion and fouling in
an effort to boost reliability, according to SWEP’s Thomson. “We have
been working on innovating coatings that we can apply to the heat
exchanger, which allow our customers to use a less expensive heat
exchanger in complicated systems
where they previously would have
needed more noble materials of
construction,” he says. “Instead, we
13
Source: Solex
a heat exchanger, the less point, as well as high long-term reliadditional steam you need ability and thermal efficiency, making
to create in the process, them suitable for concentrated solar
which is typically done in power, energy storage and poweroil- or gas-fired burners, to-X plants.
so you instantly reduce fuel
Kelvion also offers heat exchange
consumption,”
explains technologies that support sustainAlfa Laval’s Maciver. “While able and efficient solutions in the
this is the biggest driver in clean tech space, including green
traditional chemical pro- hydrogen production. “Electrolycesses, it is especially sis systems are considered to be a
true in the new clean-tech promising option for producing hyFIGURE 3. Heat-pipe heat exchangers reduce the risks and
space, which is looking at drogen from renewable resources,”
consequences of failure that plague traditional heat exchanger
new processes in hydro- says Alexander Gernhardt, senior
types through the inclusion of multiple redundancies in the heat
exchanger design
gen, carbon capture and application engineer, green technolenergy storage.”
ogies, with Kelvion. “However, these
coat it with a specifically formulated
He continues, pointing out that systems have a 60 to 80% efficiency
chemical and it provides protection these applications put new demands rate, which represents the level of
to stainless steel or less noble mate- on heat exchange solutions. “High electrical energy that will be transrials in these applications, allowing a temperatures and working with mol- formed into hydrogen. The remaining
lower cost of ownership and the use ten salts are two common challenges 20 to 40% becomes heat that can
of efficient and compact solutions.”
that we work with in this space,” either be recovered or reused in, for
For example, he says, brazed says Maciver.
example, district heating, or emitted
plate heat exchangers bring ben“We are actively looking to extend by air coolers into the ambient air.
efits in terms of thermally efficient our portfolio of heat exchangers for This means that an electrolyzer sysand compact products, but there these applications, including organic tem with 10-MW capacity will transwere some obstacles with the use R&D development and forming part- form around 2 to 4 MW of the elecof brazed plate heat exchangers, in- nerships to bring specific products trical energy supplied to the process
cluding interactions between media, and expertise into our offerings,” into heat.
which can result in corrosion, fouling, continues Maciver. “For example,
“To ensure that the electrolysis
scaling and leaching and a decrease we are in a partnership to market occurs in stable and efficient conin the performance and efficiency. our header-coil heat exchanger ditions, it is essential that all equip“But, by looking at these processes, technology, which has a long tradi- ment interacting with the process,
we found using coatings provided tion in working with molten salts and especially the heat exchangers, is
a way to mitigate the occurrence,” those that involve significant thermal carefully chosen and designed,”
says Thomson. “The use of coat- cycling, which is an issue that often Gernhardt says. “Our plate heat exings and innovating applications of leads to fatigue failures in conven- changers, shell-and-tube heat excoatings allows better resistance to tional heat exchangers.
changers, dry coolers, air fin coolers
corrosion, scaling and leaching, and
“Reliable and responsive heat ex- and cooling towers are specifically
opens markets for less expensive changers are critical to the energy designed to enhance the efficiency of
heat exchange solutions, while also transition and essential for the future the electrolysis plant and help to proallowing customers to replace older energy market, where an increasing vide a holistic approach by optimiztechnology with newer, more efficient share of intermittent renewable en- ing the different interconnected heat
versions in support of reaching sus- ergy sources is being integrated into exchangers to each other. This is of
tainability and cost goals.”
the grid,” he says.
high importance for proton exchange
The Alfa Laval Aalborg header- membrane (PEM) and alkaline water
Emerging applications
coil offers innoWhile improvements in energy effi- vative
headerciency and reliability help overcome coil technology
challenges and provide lower op- that
absorbs
erational costs in traditional chemi- thermal stress,
cal processing applications, they are minimizes equipalso fundamental in the develop- ment strain and
ment of newer sustainable-technol- eliminates leakogy and electrification innovations, age risks (Figure
according to the experts.
4). The design
Source: Alfa Laval
“Everyone is keen on efficiency features
and
right now because it directly reduces production techFIGURE 4. The Alfa Laval Aalborg header-coil offers header-coil technology that
the carbon footprint. Further, the niques ensure absorbs thermal stress, minimizes equipment strain and eliminates leakage
more efficiency you can achieve with a low approach risks
14
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Source: Lummus
FIGURE 5. Lummus’s SRT-e electric cracking heater
leverages Short Residence Time technology modified to operate using electricity, and incorporates a
modular unit-cell design that can be replicated for
plants to accommodate any commercial capacity
electrolysis (AWE) processes as the
working temperatures are moderate
and temperature differences to the
ambient are limited.”
And, as electrification of process
heating becomes a major initiative,
particularly in certain areas where
the electric grid is already decarbonized since it offers a straightforward
approach to reducing direct and
indirect emissions, heat transfer is
of growing importance, say Richard Jibb, technology director, and
Roberto Groppi, senior director for
heat exchangers, with Lummus Heat
Transfer (Houston, Texas; lummustechnology.com).
“Electric heaters, furnaces, heat
pumps and boilers are all examples
of heat transfer equipment that can
be used to reduce reliance on fossil fuels,” says Jibb. “However, using
renewable energy effectively can be
challenging due to fluctuations in energy production based on the time
of day, weather conditions and seasonal variations, such that energystorage technologies are needed to
bridge this gap by storing excess
energy during times of high production and releasing it when needed.
Energy storage technologies such
as compressed-air energy storage,
liquid-air energy storage and molten
salt or thermal storage all rely significantly on advanced heat exchanger
technologies capable of operating at
extreme temperatures and under cyclic conditions. In addition, the scale
of many industrial heating operations
presents an issue, as the electrical
infrastructure required may present a
practical limit to the amount of heating that can be converted to electrical power.”
Groppi explains: “An alternative
approach investigated by Lummus
is to use hybrid heating technologies
that can combine electrical heating with conventional heat sources
or can use electric heating when it
is available in excess, in essence
balancing the grid and reducing the
electricity supply cost.”
As such, Lummus has developed
a portfolio of solutions for electrification. The company is involved in
joint studies related to the industrial
demonstration of Lummus’s SRT-e
electric cracking heater to decarbonize a Braskem (São Paulo, Brazil; www.braskem.com.br) site in
Brazil (Figure 5). The SRT-e electric
cracking heater leverages Lummus’
proven Short Residence Time (SRT)
technology modified to operate
using electricity and incorporates
a modular unit-cell design that can
be replicated for plants to accommodate any commercial capacity.
The technology uses commercially
demonstrated components, plus an
optimum heat-flux profile, leading
to a longer radiant coil life and longer run length. In addition, decoking can be carried out on a unit-cell
basis so maintaining a spare heater
is not required.
Whether the application is existing or cutting-edge, heat exchange
technology is evolving to provide
more efficiency and reliability, as well
as a lower cost of ownership, helping to make any operation more sustainable and profitable.
n
Joy LePree
Always a step ahead!
isafe-mobile.com
ISM_MA0270_241220
Innovative mobile devices for ATEX/IECEx
with the most advanced technology.
For details visit adlinks.chemengonline.com/88111-05
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
15
Focus
Laboratory Equipment
Monitoring capabilities for
shared laboratory spaces
Elemental Machines
This product, launched as part of
this company’s Dashboard solution
(photo), is designed to add alerting capabilities to centrally located devices
within a shared laboratory space,
such as a cleanroom. The product introduces visual alert tiles, audible alert
tones and a view-only user role. The
company says that while they can be
used in any laboratory setting, these
enhancements to the Dashboard are
particularly valuable in shared spaces
where access to personal computers or phones may be limited. Laboratories can now add these alerting
features to centrally located devices
within the space, ensuring that critical information is always accessible.
The audible and visual alert options
enable more immediate notifications
of issues requiring attention within the
laboratory. When an alert is triggered,
a flashing visual tile will appear on the
screen. If the alert is not addressed,
an audible tone will sound. The viewonly user role allows staff to quickly
monitor the dashboard without needing to log in. — Elemental Machines,
Cambridge, Mass.
www.elementalmachines.com
Pfeiffer Vacuum+Fab Solutions
A handheld device for vacuummeasurement tasks
Analytik Jena
16
The TPG 202 Neo is a compact
handheld pressure gage (photo) that
can be used for measurement of
vacuum levels in laboratory systems.
The device covers the range from
5 × 10–5 to 1,230 millibars, and has a
silicone protective cover for demanding environments. The gage’s versatility allows it to be employed across
a wide spectrum of applications, from
laboratory settings to field-service
operations. One of the key features of
the TPG 202 Neo is its large internal
mass storage, which allows for continuous data collection over extended
periods. This feature simplifies data
management, because users can
easily export collected data via a
USB-C connection without needing special software, the company
says. The TPG 202 Neo’s large LCD
display supports graphic data plotCHEMICAL ENGINEERING
ting, enhancing the user experience
by providing clear and precise data
visualization. This makes it easier for
users to interpret data and make informed decisions based on real-time
information, the company adds. Applications for the TPG 202 Neo extend from measuring rough, as well
as medium, vacuum, to determining pumping speed, and performing
simple leak detection using pressure
gradient or increase measurements.
— Pfeiffer Vacuum+Fab Solutions,
Asslar, Germany
www.pfeiffer-vacuum.com
This instrument simplifies
laboratory water analysis
The multi N/C x300 series (photo) is
designed for measurement of total
organic carbon/total bound nitrogen
(TOC/TNb). These analyzers have
a robust, user-friendly design, flexible automation options and intuitive
new software. The multi N/C x300
series provides easy-to-use, highthroughput and cost-optimized instruments for environmental analysis
and the pharmaceutical sector. With
intuitive, easy-to-use software, flexible automation options and a userfriendly design, the multi N/C x300
series was developed to give users
more time for their core tasks and to
significantly reduce the time spent on
non-value-adding activities, says the
company. The series also offers high
sample throughput, durability and
low total cost of ownership. Whether
the samples are liquid or solid, particle-rich wastewater, ultrapure water,
drinking water, saline, acidic or alkaline, the multi N/C x300 analyzers deliver reliable results. — Analytik Jena
GmbH+Co. KG, Jena, Germany
www.analytik-jena.com
Tap density testing without
calibration loss
The Ultratap 500 series (photo; p. 17),
for tap density testing, is engineered
for durability, with this company
guaranteeing 25 million taps without
calibration loss. Backed by a robust
three-year warranty, the Ultratap 500
series assures reliable performance
for years, making it the most depend-
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
able choice for tap density analysis, the company says. Meeting all
major industry standards, including
USP 616 methods 1, 2, and 3, the
Ultratap 500 series supports a range
of diverse applications, including in
chemicals and pharmaceuticals. It
has 24 pre-stored ASTM, ISO and
USP methods. The instrument series
has automated drop-height detection, integrated user management
and intuitive software to ensure full
compliance while reducing the potential for human error. Designed with
user comfort in mind, the Ultratap
500 series operates at noise levels
90% lower than competing models,
the company says. Key features of
the Ultratap 500 series include easy
operation, with TruLock straps that
allow fast, secure cylinder setup, and
a responsive touchscreen that simplifies access to pre-stored and custom
methods. The device’s automated
reports provide bulk density, Carr’s
Index and Hausner Ratio, ensuring
accurate and reproducible data. —
Anton Paar GmbH, Graz, Austria
www.anton-paar.com
A rotary evaporator for
continuous distillation
The Hei-Volume Distimatic Pro
Benchtop G9BXL (photo) allows
users to fully automate the filling and
emptying of a benchtop rotary evaporator. Once programmed, the HeiVolume Distimatic Pro module fills
and drains the Hei-VAP rotary evaporator automatically and unattended.
It detects when the media supplied
has been processed and switches
itself off automatically, including the
peripheral devices. The automation
eliminates the burden of handling of
large rotary flasks, because the module can dispense viscous residues.
Cleaning is also carried out by the automatic module. The parameters for
the sensor- or time-controlled filling of
the rotary flask can be entered via the
removable 7-in. touchscreen control
panel. The time for the coated collector vessel (approx. 330 mL) to be
emptied by the compressor can also
be programmed here. In addition, the
automatic cleaning mode and manual
operation can be started. The control
box with the integrated compressor
of the Hei-Volume Distimatic Pro,
along with all of its components, can
be mounted directly on a Hei-VAP
benchtop rotary evaporator using the
CHEMICAL ENGINEERING
bracket supplied. All parts that come
into contact with the media, including the supplied tubing, are made of
chemical-resistant materials. — Heidolph North America, Wood Dale, Ill.
www.heidolph.com
This system provides
automated decontamination
With the recent launch of the SteraMist Integrated System - Standalone
(SIS-SA), this company provides a
reliable and efficient solution for decontamination of biological safety
cabinets (BSCs) and other small
spaces or enclosed areas. Designed
to meet the unique needs of cleanrooms, laboratories and other facilities with BSCs, the SIS-SA offers a
reliable, automated solution for preventing cross-contamination. Daily
disinfection is essential in these highly
controlled environments, and users
report that the SIS-SA simplifies
what was once a labor-intensive and
inconsistent process, the company
says. Factors such as stricter regulations on microbial containment, increased R&D activities and the growing prevalence of infectious diseases
and chronic illnesses all make automated decontamination more important. The SteraMist system incorporates this company’s BIT™ solution,
which utilizes a low-percentage hydrogen peroxide as its only active
ingredient and uses patented ionized
hydrogen peroxide (iHP™) technology in all systems to create superior
disinfection. — TOMI Environmental
Solutions Inc., Frederick, Md.
www.steramist.com
Anton Paar
Heidolph North America
These NIR analyzers are
designed for versatility
XDS near infrared (NIR) spectrometers
(photo) are designed for a variety of
applications, such as uniformity testing, raw material identification and process optimization in pilot plants. The
measuring modules are hot-swappable, and the instruments come with
a variety of accessories, making the
XDS Analyzers even more versatile,
says the company. Dedicated measurement modules are available to
address different sample types, and
convenient review of data is guaranteed with the user-friendly and GMP/
FDA-compliant Vision Air software. —
Metrohm USA, Riverview, Fla.
www.metrohm.com
n
Scott Jenkins
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Metrohm USA
17
Facts At Your Fingertips
Blending and Segregation Mechanisms for Solids
Department Editor: Scott Jenkins
I
n solids-handling, blending (combining two or more materials to
achieve a combined product) and
segregation (the separation of particles into distinct zones according to
particle size, shape, density or other
physical attributes) are competing
processes. This one-page reference
outlines common mechanisms by
which these processes occur.
Random and ordered blends
A random blend occurs when the
blend components do not adhere or
bind with each other during motion
through the blend vessel [1]. Particles
that form random blends can be easy
to blend, because they move easily
relative to one another, but they also
can readily separate from each other,
collecting in zones of similar particles
when forces, such as gravity, airflow
or vibration, act on the blend.
In most dry-blending applications,
particles have some tendency to interact with one another via chemical,
molecular, physical or other means
such that individual particles can agglomerate, coat or bond to one another [2]. When particle interaction
occurs, the blend is referred to as an
ordered or structured blend. In most
industrial processes, the reality is
somewhere between the two blend
types. Some particles of the blend
may have very little tendency to interact while other blend components
may have significant interaction.
Blending mechanisms
Three primary blending mechanisms
are convection, diffusion and shear.
Convection. Convection is the transfer of a collection of particles from
one location to another. This can occur as a result of material cascading
in a tumble blender, material moving
against the blade of a ribbon or paddle blender or as a result of gas-pressure pulses in a pneumatic blender.
Diffusion. Diffusion is the random
redistribution of particles that occurs as a result of increased particle
mobility. Increased mobility typically
occurs when the bulk density of the
material is decreased sufficiently to
18
Jenike & Johanson
allow individual particles to
move relative to one another.
Fluidization in fluidized-bed reactors or granulators results in
diffusion. Mechanical blenders
move collections of particles
by convection, but when the
speed of the agitator is sufficient to locally fluidize material,
diffusion occurs.
Shear. Shear occurs in a flow- FIGURE 1. Sifting segregation, where particles of varying
ing granular solid as a result sizes separate due to gravitational forces, is particularly comof a velocity gradient, and can mon in processes that involve piling materials or filling bins
develop as either a discontinunot spontaneously segregate when
ous shear (for instance, a shear or at rest, but will often readily segregate
slip plane) or as a continuous gradi- when allowed to move. For sifting to
ent of velocity. In either case, there occur, material must be free-flowing,
can be some overlap in what could have a range of particle sizes, have
be called shear and what might be some fairly large (>100 mesh) parcharacterized as convection. The ticles, and have some means of interimportant difference, as it applies particle motion [3].
to solids blending, is in the intensity. Fluidization. This type of segregation
Shear planes that develop in gravity results when finer, lighter particles rise
blending or in a tumble blender pre- to the top surface of a fluidized blend
dominantly result in mixing by con- of powder, while the larger, heavier
vection. Shear in a high-speed mixer particles concentrate at the bottom of
is more effective in breaking up ag- the bed. The fluidizing air entrains the
glomerates of fine powders and dis- fines and carries them to the top surtributing small-particle-size material face. This mechanism generally only
occurs with powders with an average
with high surface activity.
particle size smaller than 100 µm [1].
Segregation mechanisms
Fluidization segregation is likely to ocSegregation can be driven by factors cur when fine materials are pneumatiincluding gravity, electrostatic forces, cally conveyed, when they are filled
fluid-drag forces and elastic forces. or discharged at high rates, or if gas
Common segregation mechanisms counter-flow occurs. The more coheare sifting, fluidization and dusting.
sive the material, the less likely it will
Sifting. The most prevalent type of segregate by this mechanism.
segregation is sifting, which results Dusting. Particle entrainment or
in separation by particle size. Sift- dusting segregation occurs when fine
ing segregation is the most com- particles in a blend are carried by air
mon means for particles to separate. currents (such as during transfer of a
It occurs when small, fine particles blend into a container) and then settle
move through large, coarser particles preferentially at the container walls.
(Figure 1). Sifting segregation occurs This mechanism requires four conto some degree in most bulk-solids ditions: difference in particle sizes;
operations. Sifting will occur in mix- relatively large particles (average size
tures of different-sized particles when greater than 100 µm); free-flowing
particles are sufficiently large that sur- material; and inter-particle motion. n
face forces are weak relative to gravity (usually larger than 100 μm), when References
particles have mobility relative to one 1. Maynard, E., Blender Selection and Avoidance of Post-Blender
Segregation, Chem. Eng., May 2008.
another and when there is some
2. Troxel, T.G., Blending, Sampling and Segregation, Chem. Eng.,
mechanism to allow particles to
October 2012, pp. 41–46.
move relative to one another [2]. Col- 3. Marinelli, J., Will Mass Flow Solve All Your Segregation Problems?, Chem. Eng., April 2006.
lections of different size particles will
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
PARTNER INSIGHTS
S P O N S O RE D CO N T E N T
Decarbonisation & Business
Transformation
Cepsa becomes Moeve and transforms detergency sector with
the first cradle-to-gate negative carbon footprint LAB
Being in permanent transformation is the only way to
find effective solutions to the new needs society faces. With
this in mind, Cepsa, the world’s leading producer of linear
alkylbenzene (LAB), has become Moeve, a renewed busi-
acteristics, qualities, properties and performance as traditional LAB, but with a 19% reduction in carbon footprint
compared to a product manufactured with fossil energy, according to the results of the Life Cycle Assessment carried
out by the company.
The home care industry may account for around 10%
of the carbon emissions of total chemical and petrochemical emissions into the atmosphere, according to the latest
published studies, such as Saygin & Dolf Gielen, 2021, David
Bott, 2023. For this reason, reducing its impact has become
one of Moeve’s main concerns along the entire value chain
of its products.
ness concept to face future challenges.
Moeve is the result of the company’s decision to become one of the world leaders in the chemical and energy
transition, through a new business strategy called Positive
Motion. A natural and definitive step in the company’s
transformation plan to drive decarbonization in the chemical sector and in the economy through the development of
businesses based on sustainability and sustainable products.
Moeve is the world leader in the manufacture of LAB,
due to its capacity, which accounts for about 18% of the
world production. The company has carried out a strong
boost to its R&D&I activity through the production and development of pioneering chemical products that enable its
customers to achieve their goals and reduce the impact of
their carbon footprint on the environment.
For further information visit:
https://chemicals.moeveglobal.com/en/
With this philosophy, Moeve has succeeded in developing the world’s first LAB capable of achieving a carbon footprint reduction of up to -102% cradle-to-gate (according to
ISO 14064). The NextLab-R-Low Carbon. A breakthrough
for the decarbonization of the sector that is the result of
combining the use of renewable and alternative raw materials with the use of renewable energies in the production
process.
Moeve’s Next range also includes the NextLab-Low
Carbon, available for the North American market, which
is produced using renewable energy instead of traditional
fossil fuels. This process, a pioneer in the chemical sector,
makes it possible to obtain a product with the same charCHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
For details visit adlinks.chemengonline.com/88111-06
FEBRUARY 2025
19
New Products
Moisture measurement in
hazardous environments
MoistTech
SonicAire
This company’s explosion-proof sensor (photo) combines near-infrared
technology with robust safety features,
providing accuracy and reliability in explosive atmospheres. This sensor offers protection through a certified explosion-proof enclosure with conduits,
unions, elbows and nipples for secure
external connections. Even in challenging conditions, the sensor’s versatility allows accurate and consistent
moisture measurement, offering an impressive moisture range from 0–99%
with parts per million (ppm) sensitivity.
The sensor requires one-time factory
calibration and features a drift-free optical design that minimizes downtime
and reduces operational costs. Holding prevalent international certifications, the sensor ensures compliance
with global safety standards. The sensor’s robust design, featuring a hinged
cover enclosure and explosion-proof
window, makes it suitable for chemical processing, oil and gas and pharmaceutical applications. — MoistTech
Corp., Sarasota, Fla.
www.moisttech.com
These dust-control fans are now
ATEX certified
Siemens Digital Industries Software
This company has recently secured
full ATEX Zone 22 certifications for its
EX200 and EX205 2-hp dust-control
fans (photo). These fans are designed
explicitly to provide proactive protection against fugitive combustible dust
in hard-to-reach areas, enabling users
to operate more continuously without
having to stop production to clean.
Zone 22 certification ensures that fans
can operate safely in environments
where an explosive dust atmosphere
is unlikely to occur, but should dust
be present, the fans will not create
an ignition source. — SonicAire, Inc.,
Winston-Salem, N.C.
www.sonicaire.com
High-performance drive units
with cybersecurity built in
Hapman
20
Sinamics G220 (photo) is a new multipurpose, adjustable-speed drive that
features built-in technology to reduce
harmonics by up to 97% — without
the need for an a.c. line reactor or d.c.
choke. Sinamics G220 drives have an
CHEMICAL ENGINEERING
integrated web server for commissioning, which eliminates the need to install
software or an app on a PC or mobile
device. This saves time and makes
drive setup intuitive and user-friendly.
These new drives are also equipped
with an IIoT module, meaning that they
can easily be integrated into Cloud and
Edge applications, which increases the
transparency of the applications and
makes remote monitoring and accessibility of the drive system possible.
The drives come standard with integrated cybersecurity features for highly
secure communication and authentication checks to protect against tampered firmware. The Sinamics G220
is also available in a UL Type 12 (IP55)
wall-mount design, and a special conformal coating option is also available
for the operation of the drive in harsh
environments where the presence of
corrosive gases, such as hydrogen
sulfide or ammonia, is unavoidable. —
Siemens Digital Industries Software,
Nuremburg, Germany
www.sw.siemens.com
New screw conveyor offers
flexibility and easy maintenance
The Helix flexible screw conveyor
(photo) features a helicoid screw that
rotates within a fixed tube to transport
materials efficiently from one point to
another. It supports horizontal conveying up to 80 ft and vertical discharge heights of up to 40 ft, making
it adaptable to various plant layouts
and space constraints. Available in diameters ranging from 2.5 to 8 in., and
with capacities from 15 to 1,800 ft³/h,
the Helix model is suitable for many
material-transfer applications, including bulk-material transport and precise
batching and blending, effectively accommodating powders, granules and
irregularly shaped materials. This conveyor offers a variety of customizable
options, including multiple auger types
designed for different material characteristics, such as sticky substances,
fine powders and heavy, abrasive materials. Additionally, the tool-free casing removal feature facilitates quick
maintenance, enhancing operational
efficiency and minimizing downtime.
— Hapman, Kalamazoo, Mich.
www.hapman.com
■
Mary Page Bailey
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Cover Story
Gas-Flow Calculations
for Sonic Choking —
Revisited
Gas compressibility can lead to choked flow in piping systems. Presented here is an overview of
choked-flow geometries in pipes, and examples of how choked flow arises in different pipe layouts
T
he more things change, the more
they stay the same. At least that
is how the saying goes. What has
changed? The chemical process
industries (CPI), along with industry more
generally, continue to evolve and expand
the importance and breadth of fluid-system applications. And what has stayed the
same? The phenomenon of sonic choking
in superheated gas flow remains a challenge in process piping applications.
Sonic choking occurs when gases,
which are compressible, flow at velocities
that approach sonic velocity, the speed of
sound waves in a medium. A typical sonic
velocity for air is 1,000 ft/s (305 m/s).
When a flowing gas at some location in the
pipeline experiences a local velocity equal
to the sonic velocity of the gas at that temperature, sonic choking occurs.
Twenty-five years ago, an article was
published in Chemical Engineering entitled
“Gas-flow Calculations: Don’t Choke” [1]
(Figure 0). This article revisits the material
in the piece from 2000, providing clarifications, updates, points of emphasis and additional insights from the author’s experiences over the last quarter century.
Another impetus for this revisit article is
that the author recently wrote a technical
paper that details all the types of sonic
choking [2]. This included discussion of
multiple sonic choking points in series
and in parallel. In doing so, examples of
all these situations were created using
simplified assumptions, such as assuming perfect gas and adiabatic flow in horizontal pipes. This allowed the examples
to be solved using closed-form solutions
and applied in Microsoft Excel. The Excel
files are publicly available [3] for those interested and examples are included here.
CHEMICAL ENGINEERING
Trey Walters
The goal of the present article is not to Applied Flow
just repeat discussions from Ref. 1. Rather, Technology
the purpose is to offer some clarifications
and reinforcements to the previous article.
And the Excel-based examples from Ref. 2
will be used to provide a hands-on, accessible learning tool for those interested in a
QUICK REVIEW OF SONIC
deeper dive.
CHOKING
Even though a quarter century has
passed, the author continues to see enGEOMETRY OF SONIC
gineers trying to use incompressible-flow
CHOKING
methods on compressible-gas systems
SOLVABLE BOUNDARY
and using or promoting the debunked
CONDITIONS
“40% pressure drop rule.” Please consult
Ref. 1 for a thorough explanation of why IMPORTANT EQUATIONS
“rules of thumb” like this and other simi- PREFACE TO EXAMPLES
lar ones can be highly misleading. Finally,
guidance is provided for what to look for SINGLE CHOKE POINT
EXAMPLES
when evaluating software for modeling
MULTIPLE CHOKE
pipe systems where sonic choking might
POINTS IN SERIES
occur.
IN BRIEF
MULTIPLE CHOKE
POINTS IN A SEQUENCE
OF PIPES
DOWNSTREAM OF
CHOKE POINTS
APPLICATION OF
EQUATION (2)
SIMPLIFIED TO
COMPLICATED
DO YOU KNOW WHAT
k IS?
SOFTWARE FOR SONIC
CHOKING
CORRECTIONS
FIGURE 0. The cover of the Chemical Engineering issue from
January 2000 is shown here, featuring the author's original
article, as cited in Ref. 1
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
21
Geometry of sonic
choking
FIGURE 1. Each of these pipe configurations can
result in sonic choking
Quick review of sonic choking
Sonic choking occurs when the gas
bulk velocity reaches the gas sonic
velocity somewhere in a pipe system. This is another way of saying
that the Mach number reaches 1.
When this happens in a sequential run of pipes, then lowering the
downstream pressure will not produce any additional flow. Figures 3
and 4 from Ref. 1 and the associated discussion there do a good job
of elaborating. Further discussion
on sonic choking can also be found
in Ref. 2.
When the first article was published in 2000, the author was under
the impression that a sonic choking
point involved a shock wave. After
discussions of this concept with several other knowledgeable engineers
over the years since the publication,
he is now unsure of this, and has
stopped calling it a shock wave. Regardless, a sonic choking point is (at
minimum) similar to a shock wave in
that it involves a discontinuity in the
flow field. Therefore, whether or not
there is a shock wave is somewhat
irrelevant. A discontinuity exists, and
that is what is important.
FIGURE 2. The diagram here shows types of solvable boundary condition combinations for a pipe or
pipe sequence (flow from left to right)
22
NOMENCLATURE
Cross-sectional area (ft2 / m2)
A
Both Refs. 1 and 2 disSpecific heat at constant pressure and
cp, cv
volume (Btu/lbm · R, kJ/kg · K)
cuss in depth the three
geometric
situations
D
Inner diameter (ft / m)
where sonic choking
Friction factor, Darcy-Weisbach (dimensionf
occurs. Because the
less quantity)
examples from Ref. 2
L
Length (ft / m)
to be explored here are
∙
Mass flowrate (lbm/s / kg/s)
m
designed to examine
M
Mach number (dimensionless quantity)
all the possibilities of
these three geometries,
P, Po
Static and stagnation pressure (psi / kPa)
including cases where
R
Molar gas constant (Btu/lbm-R or J/kg-K)
two, or all three, geomStatic and stagnation temperature (°F / °C)
T, To
etries are happening in
Specific volume (ft3/lbm, m3/kg, inverse of
the same system, the
v
density)
three situations are disCompressibility factor, correction for non-ideal
cussed here.
Z
gas (dimensionless quantity)
1. Endpoint choking
Isentropic expansion coefficient, also known
(Figure 1, top diagram).
γ
as k (dimensionless quantity)
Endpoint choking occurs when the gas pressure in the pipe cannot
drop down to the discharge pres- Important equations
sure without accelerating to sonic A form of the mass-conservation
velocity thereby resulting in a choke equation is highly useful for gas-flow
point (and pressure discontinuity) at calculations in pipes, in general, and
for sonic-choking calculations spethe end of the pipe.
2. Expansion choking (Figure 1, cifically (Equation (1) [1, 2]).
middle diagram). Expansion choking
occurs when there is an increase in
(1)
pipe area, such as an expander, diverging tee, or discharge into a large
header pipe. Here, the gas canBecause choked flow occurs when
not navigate to the pipe discharge
downstream without accelerating to the Mach number equals 1, Equation
sonic velocity at the point where the (1) becomes Equation (2).
area increases. A choke point and
pressure discontinuity thus occurs.
3. Restriction choking (Figure 1,
bottom diagram). Restriction chok(2)
ing occurs when there is restriction (resultting from an orifice or valve,
A closed-form solution of adiabatic
for example) where the gas cannot
navigate through the restriction with- flow in constant-diameter pipes can
out accelerating to sonic velocity. A be found in most compressible-flow
choke point and pressure disconti- textbooks where the pipe is horizontal with a constant friction factor
nuity thus occurs at the restriction.
(Equation (3) [1, 2]):
Solvable boundary conditions
In a sequence of pipes, there are
three types of solvable boundary
conditions [2], as depicted in Figure
2. Repeateed reference to Figure 2,
diagrams A, B and C will be made
throughout the following seven examples in order to point out which
part of the choked pipe system is
solved with which combination of
boundary conditions.
CHEMICAL ENGINEERING
(3)
Note that Equation (3) is sometimes presented without all the parenthetical groupings, which can be
misleading. For example, the author
did this in Equation 11 from Ref. 1.
The Equation (3) form here is pre-
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
FIGURE 3. Endpoint choking input data (top) and
output data (bottom) are shown for Example 1
ferred because it makes clear the
otherwise ambiguous parenthetical
groups. Equations (1) to (3) are applicable for real gases.
Preface to all examples
In order to provide closed-form solutions in Microsoft Excel, simplifying assumptions are required. All
examples assume the flowing gas is
air, follows the ideal gas law, is calorically perfect, with an isentropic expansion coefficient of 1.4. All pipes
are assumed to be adiabatic, constant-diameter and horizontal, which
allows Equation (3) to be used. Entrance losses are ignored.
Including real-world behavior, such
as heat transfer, real gas behavior,
sloped pipes and varying friction
factors, is important and will be discussed in a subsequent section.
Space limitations do not allow a
thorough discussion of all examples,
so brief information will be given
about each one. Refer to Ref. 2 for
more details.
Single-choke-point examples
Example 1: Endpoint choking,
single choking point. Figure 3
CHEMICAL ENGINEERING
(top) shows the input for Example
1, endpoint choking, and Figure 3
(bottom) shows the output. Here,
the Figure 2a boundary condition
combination is used. From Figure 3
(bottom), any discharge pressure at
or below 95.3 psia (657.1 kPa) will
result in choking.
Example 2: Expansion choking,
single choking point. Figure 4
(top) shows the input for Example
2 (expansion choking), and Figure
4 (bottom) shows the output. The
input data for Pipe 1 is the same
as for Example 1. Here, the Figure
2a boundary condition combination
is used for Pipe 1. How is Pipe 3
solved? Once the choked flowrate
is determined for Pipe 1, that becomes a known boundary condition
to use for the inlet of Pipe 3. Hence,
Pipe 3 is solved using the Figure 2c
boundary-condition combination.
From the Law of Conservation of
Mass, the mass flowrate in Pipe 3 is
the same as that in Pipe 1. Further,
from the energy conservation law,
the stagnation enthalpy at the inlet
of Pipe 3 must match the outlet of
Pipe 1 [2] regardless of whether the
pipes are adiabatic or not.
Example 3: Restriction choking, single choking point. Figure
5 (top) shows the input for Example
3 (restriction choking) and Figure
5 (bottom) shows the output. The
input data for Pipe 1 is the same
as Example 1. Here, the Figure 2a
boundary condition combination is
used for Pipe 1. Once the choked
flowrate at point J2 is determined,
that becomes a known boundary
condition to use for the inlet of Pipe
2. Hence, Pipe 2 is solved using
the Figure 2c boundary condition
combination. Similar to Example
2, mass and energy conservation
across J2 will determine the mass
flowrate and stagnation enthalpy at
the inlet of Pipe 2.
in endpoint choking occurring at
point J4. Hence there are two sonic
choking points. Figure 6 (bottom)
shows the output. Similar to Example 2, the Figure 2a boundary
condition combination is used for
Pipe 1 and the Figure 2c boundary
condition combination is used for
Pipe 3. Mass and energy conservation across J3 determine the conditions at the inlet of Pipe 3, similar to
Example 2.
Example 5: Two choking points
in series with restriction choking first. Example 5 is the same
as Example 3 (with Figure 5, top),
except with one change. The downstream pressure is reduced from
100.6 psia (693.5 kPa) to 50 psia
(344.7 kPa). Figure 7 (top) shows
the input. This results in endpoint
choking occurring at J4. Hence,
there are two sonic choking points.
Figure 7 (bottom) shows the output.
Similar to Example 3, the Figure 2a
boundary condition combination is
used for Pipe 1 and the Figure 2c
boundary condition combination is
used for Pipe 2. Mass and energy
conservation across J2 determine
Multiple choke points in series
Example 4: Two choking points
in series with expansion choking
first. Example 4 is similar to Example 2 (Figure 4, top), except for one
change. The downstream pressure
is reduced from 100.6 psia (693.5
kPa) to 50 psia (344.7 kPa). Figure
6 (top) shows the input. This results
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
FIGURE 4. Expansion choking input data (top) and
output data (bottom) are shown for Example 2
23
Multiple choke points in a
sequence of pipes
When there is more than one choking point in a sequence of pipes, the
first choking point controls the mass
flowrate for the entire sequence.
While the choking points downstream do not control the flowrate,
they do control how the pressure
is distributed and, hence, the pressure profile. For example, consider
Figure 8 (bottom) from Example 6.
The first choking point here is at the
J2 restriction choking point, and
this controls the flowrate (14.74
lbm/s / 6.69 kg/s). The J3 and J4
choking points control how the profile graphs appear in Figure 8 (bottom) downstream of J2.
Multiple choke points in
parallel
FIGURE 5. Restriction choking input date (top) and
output data (bottom) are shown for Example 3
the conditions at the inlet of Pipe 2,
similar to Pipe 3 in Example 3.
Example 6: Three choking points
in series. Figure 8 (top) shows the
input for this example. This situation
results in restriction choking at J2,
expansion choking at J3 and endpoint choking at J4. Hence, there
are three sonic choking points. Figure 8 (bottom) shows the output.
The Figure 2a boundary condition
combination is used for Pipe 1 and
the Figure 2c boundary condition
combination is used for Pipe 2 and,
again, for Pipe 3. Mass and energy
conservation across J2 and J3 determine the conditions at the inlet of
Pipe 2 and Pipe 3, similar to previous examples.
24
Example 7: Four choking points
in parallel flow paths. Figure 9
(top) shows the input. This results in
restriction choking at J12 and J22,
and endpoint choking at J13 and
J23. Hence, there are four sonic
choking points. Figure 9 (bottom)
shows the output, which is more
complicated than previous examples because of the flow split at J11
and the parallel paths. Also, the two
choked-flow paths are non-symmetrical (Figure 9, top) and, hence,
have different flowrates. The Figure
2a boundary-condition combination
is used for Pipe 1, Pipe 11 and Pipe
21. The Figure 2c boundary-condition combination is used for Pipe
12 based on the choked flow in the
J12 orifice, and for Pipe 22 based
on the different choked flow rate in
J22 orifice.
Mass and energy conservation
across J12 and J22 determine the
conditions at the inlets of Pipe 12
and Pipe 22, similar to previous examples. While this example could
be solved in Excel using excessive
manual iteration for the conditions
at J11, this was skipped, and results came from the commercial
software AFT Arrow [4]. Note that
in Ref. 1, version 2 of the software
was used, but for this exercise, version 10 was used.
Finally, if conditions were right,
one more choking point could exist
in this system. This would be at the
CHEMICAL ENGINEERING
J11 node, which expands into P11
and P21. It is possible for expansion choking to exist at the end of
Pipe 1 here. This would occur, for
example, by reducing the diameter
of Pipe 1 to 2 in (51 mm) and reducing the pressures at J13 and J23 to
15 psia (103 kPa). This would result
in 5 choking points in Figure 9a.
Downstream of choke points
Many conditions exist downstream
of choke points that process engineers may need to know. Among
these is to understand how the flow
of gas will distribute to parallel delivery points and what the process
conditions are at those delivery
points. A more complete list of these
conditions can be found in Section
6.5 of Ref. 2.
Application of Equation (2)
In order to correctly determine the
choked flowrate, Equation (2) must
be applied at each local choke
point. That means that for each
of the examples presented, accu-
FIGURE 6. Expansion choking input data (top) and
output data (bottom) are shown for Example 4,
for two choking points in series, with expansion
choking first
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
determine conditions downstream of
choke points. In most real systems,
Equation (3) will not get you far. Realworld effects, such as heat transfer
between ambient surroundings and
the gas will need to be accounted
for. Other effects include real gas
behavior, sloped or vertical pipes,
variable friction factors and complex
pipe networks. A capable software
tool that accounts for all these effects is essential to obtain accurate
predictions in such situations [4].
Do you know what γ (or k) is?
The isentropic expansion coefficient
is commonly called γ by gas dynamicists (or k by thermodynamicists).
In engineering school, the author
learned the following relationship,
shown in Equation (4):
(4)
FIGURE 7. Restriction choking input data (top) and
output data (bottom) are shown for Example 5 for
two choking points in series
rate knowledge of the stagnation
pressure and temperature, Po, and
To, must exist at each local choke
point. When conditions are ideal,
like the examples presented here,
it is more straightforward to determine these conditions using equations such as Equation (3). However, when real-world conditions
must be accounted for, it is quite
complicated to determine Po and
To at each choke point. Indeed,
determining these values depends
on knowing the mass flowrate —
which is the variable for which we
are solving. In such cases, heavy
numerical iteration is needed using
the governing conservation equations. The original article [1] discusses these in more detail.
Simplified to complicated
Simplifications such as Equation (3)
and the examples presented here
are useful to gain an appreciation
of how to navigate single or multiple
sonic choking points — and how to
CHEMICAL ENGINEERING
However, a little-known fact [5] is
that Equation (4) is actually an approximation, and is the simplified
form of the full definition of γ, as
shown in Equation (5):
(5)
It is often the case that the “correction term” on the righthand side
of Equation (5) is close to unity, thus
making Equation (4) approximately
correct. On the other hand, the author has found that the complete
Equation (5) is commonly required in
gas-pipe analysis in order to obtain
accurate results.
Part of the reason for discussing
this here is that after Ref. 1 was published in 2000, there was a respectful,
but critical, letter to the editor in a subsequent issue specifically about the
assumptions in the 2000 article. An
exchange of letters occurred, where
Equation (5) was offered as being preferred to Equation (4), which satisfied
the critic that the assumptions used in
Ref. 1 were, in fact, sound.
Sonic choking analysis software
In order to accurately predict sonic
choking in pipe systems, software
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
FIGURE 8. Input data (top) and output data (bottom) are shown for Example 6, for three choking
points in series
solutions should be able to handle
all types of sonic choking, including multiple choking points in series
and parallel. Further, a proper energy
balance should be performed on the
pipes and choke points. Features
such as heat transfer, sloped pipes
and real-gas modeling is recommended. For a complete list, see
Section 9 in Ref. 2.
Corrections to Ref. 1
The revisiting of the 2000 sonic
choking article allows us to correct
some typographical errors in Ref. 1
that I found after publication. All errors were the fault of the author.
Equation (14c) in Ref. 1 should
have a negative sign, as shown in
Equation (6).
(6)
Equation (14e) in Ref. 1 should
read, as follows in Equation (7).
25
FIGURE 9. Input data (top) and output data (bottom) are shown for Example 7, for four choking
points in two parallel flow paths
(7)
Concluding remarks
the Experts
Call
for all your solids processing
Solids Mixing
References
Applications:
Ribbon & Cone Blenders
Fluidizing Mixers
Sigma Blade Mixers
APIs ∙ Ag-Chemicals
Size Reduction
Food Ingredients
Biologics ∙ Catalysts
Ceramics ∙ Chemicals
(also for high-viscosity mixing)
Wet & Dry Size Reduction
Steel & Ceramic Lined Mills
Jars & Jar Rolling Mills
Herbicides ∙ Minerals
Vacuum Drying
Polymers ∙ Powdered Metals
Dryers & Complete Systems
Important concepts from a 25-yearold article in Chemical Engineering
are clarified and reinforced. The
seven simplified examples in this
article demonstrate all the different
types of sonic choking configurations with closed-form solutions in
Excel. Accounting for real-world
gas-flow effects (such as heat
transfer) is crucial to obtain accurate
predictions. Advice on evaluating
commercial software for compressible flow analysis is given. Engineers
are cautioned to question common
compressible flow calculation “rules
of thumb,” such as the so-called “40% pressure drop
rule.” Other “rules of thumb” that often lead to confusion are found in the original article. n
Edited by Scott Jenkins
Nutraceuticals ∙ Pesticides
Pharmaceuticals ∙ Pigments
Proteins ∙ Resins ∙ Vitamins
1. Walters, T. W., Gas-flow Calculations: Don’t Choke, Chem. Eng., January 2000.
2. Walters, T. W., A Comprehensive Discussion of Sonic Choking In Pipe Systems For Steady, Compressible Flow, presented at the 2024 ASME Pressure Vessel and Piping Conference, PVP2024123592, July 28 to August 2, 2024.
3. Walters, T.W., A Comprehensive Discussion of Sonic Choking In Pipe Systems For Steady, Compressible Flow, auxiliary data files, https://www.aft.com/technical-papers/a-comprehensive-discussion-of-sonic-choking-in-pipe-systems-for-steady-compressible-flow (2024).
4. AFT Arrow 10, Applied Flow Technology, Colorado Springs, Colo., 2024.
5. Bejan, A., “Advanced Engineering Thermodynamics,” 4th Ed., 2016, pp. 169–170.
Author
Trey Walters, P.E., is the founder and chairman of Applied
Flow Technology (AFT; 2955 Professional Place, Colorado
Springs, CO 80904; Phone: 719-686-1000; Email: treywalters@aft.com). His role today is working with AFT team
members and customers to deliver industry-leading fluidtransfer-system simulation solutions. He has developed commercial software products on a variety of fluid system applications including compressible flow in pipe network systems.
He has managed and performed consulting projects in numerous process industries. He holds B.S. and M.S. degrees
in mechanical engineering from the University of California, Santa Barbara. He is a
Fellow of the American Society of Mechanical Engineers (ASME).
Quality &
Innovation Since 1911
www.pauloabbe.com
855-789-9827
sales@pauloabbe.com
For details visit adlinks.chemengonline.com/88111-07
26
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Feature Report
Part 1
Scaling Industrial
Decarbonization with
Advanced Membranes
The potential of membrane technology to unlock hybrid and scalable carbon capture,
combined with results from early field trials, suggest that advanced membranes will
play a crucial role in enabling more widespread adoption of decarbonization strategies
I
t is a truth universally acknowledged
that today’s industrial carbon dioxide
sources are in want of a path towards
decarbonization. Accounting for approximately 30% of global greenhouse-gas
emissions when considering both direct
and energy-related sources, the chemical
process industries (CPI) are facing mounting pressure to decarbonize. While electrification and renewable energy have made
significant strides in other areas, deep industrial decarbonization requires more innovative solutions. Enter carbon capture,
utilization and sequestration (CCUS) — a
technology platform that has emerged as
a crucial component in all pathways toward
achieving carbon neutrality by 2050.
However, the implementation of CCUS at
scale faces a significant hurdle: the cost and
efficiency of carbon capture itself. Today, carbon capture is estimated to represent over
half of the overall cost of CCUS, making it the
step most ripe for innovation and cost reduction. The key to enabling widespread CCUS
adoption lies in developing and deploy- Christine
ing high-efficiency, scalable gas-separation Parrish
technologies that can successfully address Ardent Technologies
the dilute nature of CO2 emissions.
Challenges for carbon capture
In addition to the dilute nature of industrial CO2 emissions, the wide variation in
emissions, site-specific constraints and
downstream destinations of captured
CO2 all present challenges for industrial
carbon capture.
Different industrial processes produce fluegas streams with vastly different CO2 concentrations. For example, the CO2 content in
steel-production emissions (24%) differs significantly from that in cement manufacturing
(16%) or power plants (11%) [1]. Additionally,
industrial fluegas streams often contain various impurities and toxins, which can impact
the effectiveness and longevity of capture
technologies (Figure 1).
Site-specific constraints, such as available
space, utility access and existing infrastructure, can limit the types of capture
Shutterstock
technologies that can be deployed
at a given location. It doesn’t matter how theoretically cost-effective
a technology may be if the plant
considering it simply doesn’t have
the space available to install it, or
can’t acquire the utilities necessary
to run it.
The intended use or storage
method for the captured CO2 also
influences the requirements for
carbon capture technology. While
transport and storage applications
for CO2 typically require very high
FIGURE 1. One of the major challenges in industrial carbon capture is the
purity
(99.8%), many utilization apvariance in CO2 concentration in fluegas streams, as well as the wide spectrum of impurities that can potentially be present in the exhaust gas
plications do not. Local economic
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
IN BRIEF
CHALLENGES FOR
CARBON CAPTURE
CONVENTIONAL CCUS
STRATEGIES
NEW MEMBRANES
MODULAR AND
SCALABLE
TECHNOLOGY
AN ADAPTER FOR
HYBRID SOLUTIONS
LOW-RISK
TECHNOLOGY
27
TABLE 1. FIELD-VALIDATED CARBON-CAPTURE APPLICATIONS
fer from high enFOR ADVANCED MEMBRANES
ergy requirements
Location
Industry/application
(parasitic load) for
Voestalpine
Steel production
solvent regeneration, solvent deg- RHI Magnesita
Refractory materials production
radation issues, OMV Austria
Petrochemicals production
and potential for
Norcem/Norwegian University of
Cement manufacturing
chemical
emis- Science and Technology [4 ]
sions. They also
Wyoming Integrated Test Center/
Natural-gas combined-cycle
rely on economies Ohio State University [5 ]
power plant
of scale, making
them unsuitable
for smaller applications. The exten- offer several advantages for carbonsive balance-of-plant equipment es- capture applications that allow them
sentially requires a chemical plant to fill the gaps left by conventional
Conventional CCUS strategies
on-site, access to large amounts of technologies. FTMs can effectively
It’s not what we say or think about steam, and the technology has limited separate CO2 from dilute streams at
technologies that defines their place, potential for significant performance pressures as low as 1.4 bara, signifiit’s what they do — and don’t do. improvements due to its maturity.
cantly reducing energy requirements.
Before delving into the potential of Traditional membranes — best for Their high selectivity and flux allow
advanced membranes, it is worth high-pressure applications. What for processing large gas flows in a
examining the limitations of existing about traditional membranes? What relatively small footprint, resulting in
carbon capture technologies. While role might they play in carbon cap- a modular and compact design.
existing technologies have an im- ture? Traditional membranes, while
FTMs represent a significant leap
portant role to play in industrial de- already used in CO2 processing, forward in membrane technology.
carbonization, they tend to be better have primarily been developed for Unlike conventional separation techsuited for either large-scale capture high-pressure applications. The low- nologies, FTMs rely on the chemistry
in chemical plants or capture from pressure nature of fluegas presents of the membrane itself for energyhigh-pressure applications (Figure 2), challenges, including high energy efficient separation. They contain
leaving a wide range of applications costs associated with pressuriz- embedded carrier molecules that seunderserved across many industries, ing fluegas streams, which can add lectively interact with and transport
including cement, steel, glass, pulp- more than $80 per ton to the cost of target molecules (in this case, CO2)
and-paper and waste-to-energy, to capture. Furthermore, solution-diffu- across the membrane. This selective
name a few.
sion membranes require large mem- transport results in high selectivity,
Amines — best for large chemi- brane surface areas and have lim- as the carrier molecules facilitate the
cal plants. Amine scrubbing is the ited fouling tolerance, necessitating transport of CO2 while impeding the
go-to technology for large-scale car- additional feed conditioning for gas passage of other gases.
Unlike amine-based systems,
bon capture in chemical plants [2]. streams with high impurities. The limIn large-scale applications able to itations of existing amine and mem- FTMs do not rely on chemical solhandle the energy and chemical re- brane technology have created a gap vents, eliminating issues related to
quirements, amines work well, can be in the market for a technology that degradation, emissions and regendeployed now, and are low risk. How- can efficiently and cost-effectively eration. Utilizing FTMs as part of
ever, there are thousands of industrial capture CO2 from diverse industrial a composite membrane typically
applications where amines are not a sources, particularly those with lower consisting of a thin, selective layer
natural fit. Amine-based systems suf- pressure streams, low CO2 con- supported by a porous substrate,
centrations, smaller allows for high flux rates along with
Shutterstock
distributed
opera- good selectivity. This unique comtions, or challenging bination of properties allows FTMs
operating conditions. to achieve efficient CO2 separation
without the need for high pressure
New membranes
or chemical regeneration, making
Facilitated
trans- them an attractive option for a wide
port is an advanced range of industrial applications.
membrane technology that is emerg- Modular and scalable technology
ing as a natural fit Next-generation membrane solufor carbon-capture tions boast a modular, scalable and
applications.
Fa- flexible design that makes them
FIGURE 2. Conventional amine-based carbon-capture processes are
cilitated
transport
highly adaptable to the needs of
well-suited for large-scale, established processes, such as those found in
membranes (FTMs) different industrial applications and
chemical plants
factors, regulatory environments and
access to transportation, utilization or
storage opportunities all play a role in
determining the most suitable downstream destination, and by extension,
the most suitable capture solution.
Given this complexity, it is clear
that no single technology will be the
best across the entire spectrum of
applications and CO2 concentrations. Instead, the industrial sector
will require a combination of technologies to achieve cost-effective
CCUS at scale.
28
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
downstream CO2 destinations.
Membranes can easily be integrated into a simple turnkey system
that delivers an end-to-end solution
for users.
By operating at low pressures
without the need for chemical regeneration, advanced membranes
present a smaller-footprint, lowerenergy and lower-complexity alternative to conventional technologies.
Membranes are a totally electrified
solution that do not require steam
or chemical waste disposal. This
simplicity translates to lower capital and operating costs, especially
for smaller or distributed applications like kilns, compressor stations, or boilers. Thanks to their
compact design and minimal utility
requirements, advanced membrane
systems can also be more easily integrated into existing industrial facilities that face space and
utility constraints.
Membranes can be banked in series or parallel configurations, making them adaptable both to a wide
range of CO2 concentrations and
operating conditions and also to
fluctuations in industrial processes.
Robust membrane designs can tolerate various contaminants (including oxygen and water), potentially
reducing or eliminating the need for
expensive pre-treatment of fluegas
that might otherwise be required for
applications such as incinerators,
steel furnaces, kilns or applications
with high concentration of oxides of
sulfur and nitrogen (SOx and NOx).
For CO2-mineralization or biologic-utilization applications that
do not require extremely high purities, the flexible nature of advanced
membrane solutions means they
can provide a cost-effective way to
achieve the necessary concentration levels without overengineering
the solution. Membranes can be
configured to deliver 60–85% purities, avoiding unnecessary power
or system capital associated with
technologies that only deliver
higher-than-needed purities.
The modular and flexible nature
of membrane systems makes them
easy to scale and adapt according to the size and specific capture requirements of different CO2
sources, especially those underserved by incumbent technology.
An adapter for hybrid solutions
While advanced membranes offer
significant advantages on their
own, they are also poised to unlock hybrid solutions for carbon
capture. Hybrid systems combine
multiple technologies and play to
the strengths of each to achieve
optimal performance and costeffectiveness. Hybrid solutions are
especially important for industrial
carbon capture because they have
the potential not only to deliver
more efficient and cost-effective
separation when compared to single-technology solutions, but also
to address applications where no
one technology would meet the
desired specifications.
Advanced membranes can help
enable hybrid solutions because
For details visit adlinks.chemengonline.com/88111-08
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
29
they can act as a “universal adapter”
that provides a simple, modular
way of combining technologies.
Advanced membranes can take
fluegas streams with varying CO2
concentrations and impurities and
deliver them at concentrations and
purities needed to efficiently feed a
second-stage technology.
Hybrid solutions can be used either as a greenfield solution where
there is not already carbon capture
in place, or as a retrofit to make
existing carbon capture more costeffective and energy-efficient.
One promising greenfield hybrid
configuration combines membranes
with cryogenic distillation. This
combination is particularly effective
for applications requiring very high
purity CO2 (greater than 99.8%)
for transport or storage. The membrane system performs the bulk
separation, concentrating the CO2
to an intermediate level before supplying it to the cryogenic unit that
further purifies the stream to meet
stringent specifications.
In cases where amine systems
are already installed or preferred
for high-volume applications, membranes can be used to pre-concentrate the fluegas, reducing the size
and energy requirements of the
amine unit [3].
For applications with lower purity
requirements or where pressureswing adsorption (PSA) is already
in use, a membrane pre-concentration step can significantly improve overall system efficiency.
Emerging metal-organic framework
(MOF) technologies for CO2 capture could benefit from membrane
pre-concentration to optimize their
performance and reduce overall
system costs. Whether you combine them with cryogenics to deliver sequestration-ready CO2 or
only pay for the concentration you
need for utilization options, membranes can help unlock a low-cost
process configuration.
The key to successful hybrid solutions lies in proper integration and
optimization. Advanced membrane
systems are designed to fit inside
plants and close to flue stacks for a
hub-and-spoke design that can also
be less capital-intensive. This mod30
ular design allows for easy integration with existing assets and second-stage technologies, simplifying
hybrid projects and accelerating
deployment. By leveraging the best
operating regimes of each technology, engineers can design systems
that maximize energy efficiency
and CO2 recovery while minimizing
overall costs.
The potential of advanced membrane technology for carbon capture is not just theoretical. Several
pilot projects and field tests have
demonstrated the capabilities of
FTMs in real-world industrial settings, with several relevant highlighted projects listed in Table 1. In
all of these cases, the performance
of the FTM membranes exceeded
expectations set by laboratory testing, underscoring their potential for
industrial-scale applications.
Low-risk technology
As demand grows, the industry will
need to scale up the production
of high-performance membranes,
while maintaining quality and reducing costs. Many an entrepreneur’s
imagination is very rapid; it jumps
from the laboratory to a pilot plant,
from pilot to commercialization in
a moment. But in the case of advanced membranes, ample evidence suggests low risk on the path
to commercialization and scaleup.
The industry has extensive experience manufacturing and engineering membrane process solutions,
from natural gas sweetening to biogas, hydrogen and kidney dialysis.
Manufacturers can produce millions
of square meters of membranes
annually and have successfully productized membrane processes.
Advanced membrane solutions
combine low manufacturing risk
with field validation to offer low
overall delivery risk. Numerous
technology providers and project
integrators are already exploring
partnerships with membrane solution providers to enable hybrid
solution deployments.
As industry searches for a path
towards
decarbonization,
advanced membrane technology is
emerging as a promising solution
for efficient and cost-effective carCHEMICAL ENGINEERING
bon capture. The unique properties of FTMs make them particularly well-suited to fill the gaps left
by conventional capture technologies. Advanced membrane solutions address the challenges of
small, distributed, or dirty fluegas
streams, offering a flexible, modular and energy-efficient approach to
carbon capture.
Moreover, the ability of advanced
membranes to act as a “universal
adapter” that connects the dots between different novel and conventional capture technologies opens
up new possibilities for carbon
capture solutions across a wide
range of industrial applications. By
combining the strengths of membranes with other established and
emerging technologies, industrial
operators will be able to create integrated hybrid systems that optimize
performance and minimize costs
according to the needs and constraints of their facilities.
We have only just begun to see
what the new frontier of membranes
can do, and as more development
takes place, expect even more advances to come in the future.
■
Edited by Mary Page Bailey
References
1. Watson, J. C. and others, Techno-economic process optimization for a range of membrane performances: What provides
real value for point-source carbon capture?, Carbon Capture
Science & Technology, Vol. 11, June 2024.
2. Jenkins, S., Advancing Industrial Carbon Capture, Chem. Eng.,
Oct. 2022, pp. 13–18.
3. Yu, M. C. and others, Hybrid CO2 capture processes consisting of membranes: A technical and techno-economic review,
Advanced Membranes, Vol. 3, 2023.
4. Hägg, M. B. and others, Pilot Demonstration – Reporting on CO2
Capture from a Cement Plant Using Hollow Fiber Process,
Energy Procedia, Vol. 114, July 2017.
5. Clevenger, C., DOE invests $12M in novel membrane technology
that captures carbon emissions, The Ohio State University College of Engineering press release, January 18, 2024.
Author
Christine Parrish is the vice president of technology solutions at
Ardent Process Technologies (15
Reads Way, Suite 100, New Castle,
DE 19720; Email:cparrish@ardenttechnologies.com). She received her B.S.Ch.E. from the University of Delaware. Parrish began
her career in research where she
focused on the study of composite
membranes for olefin-paraffin gas separations. She currently leads a cross-functional team to translate technical attributes into tangible value propositions and successfully transition products from the laboratory into the
field. Outside of her work with Ardent, Parrish sits on the
Industrial Advisory Board for the Bioprocessing Separations Consortium and serves as the Past Chair for the
Young Professionals Committee for the American Institute of Chemical Engineers (AIChE).
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Feature Report
Part 2
Proton-Exchange Membranes:
Design Strategies for Water
Electrolysis
Designing a proton-exchange membrane that will balance the efficiency, durability
and safety requirements for hydrogen production requires careful consideration of
materials and chemistry
A
mong the ongoing efforts to curb
climate change, researchers are
actively pursuing the further development of water electrolysis
technologies for the production of cleaner
hydrogen. “Green” hydrogen can be manufactured through water electrolysis using
renewable energy. One method of water
electrolysis utilizes a proton-exchange
membrane (PEM). Compared to other
water electrolysis methods, PEM electrolysis demonstrates several key advantages,
including compact design, high electrolytic
efficiency, stability and a robust response
to fluctuating power sources [1–3]. The
mechanics of a PEM electrolysis cell are
depicted in Figure 1. Within the electrolysis cell, a PEM, usually less than 200 mm
in thickness, separates the anode and cathode. Upon applying voltage, water electrolysis proceeds in the following sequence:
1. Water is oxidized at the anode, generat-
ing protons and oxygen
2. The protons are transported to the counter-electrode (cathode) through a PEM
3. Protons are reduced at the cathode, and
hydrogen is produced
A gas-diffusion layer (GDL) helps to facilitate the efficient release of generated gases
during water electrolysis, thus inhibiting
bubble adhesion on the catalyst layer. As a
result, water can access the catalyst more
efficiently at the anode, promoting the oxidation reaction of water.
In industrial applications, hydrogen is utilized as a high-pressure gas. Therefore, two
types of compression methods are typically considered for water electrolysis. One
involves compressing ambient-pressure
hydrogen produced by water electrolysis
using a compressor. The other method involves elevating the pressure (to greater than
3 MPa) of the produced hydrogen within a
sealed electrolytic cell and cylinder. In the
latter method, especially in
cases where only the cathode side is pressurized (denoted as differential highpressure water electrolysis),
there is no need for a compressor, which can lead
to more efficient hydrogen
production [4].
Hydrogen obtained from
water electrolysis contains
moisture that often must be
removed prior to the hydrogen’s end-use application.
However, pressurizing hydrogen within water electrolyzers decreases the water
content of the generated
hydrogen. Therefore, differFIGURE 1. A typical structure of a PEM cell for water electrolysis is depicted here [1 ]
ential high-pressure PEM
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Yusuke Chiba,
Shintaro
Hayabe and
Toshiaki
Sawada
AGC Inc.
Shunsuke
Tsukuemoto
and Will Salem
AGC Chemicals
Americas
IN BRIEF
MAKING AN EFFECTIVE
PEM
PFSA POLYMERS
PEM DESIGN STRATEGY
31
TABLE 1. CONSIDERATIONS FOR EFFECTIVE PEM ELECTROLYSIS
water electrolysis is a highly efficient and high-purity hydrogen
production method.
Making an effective PEM
Required PEM
characteristics
Reducing production costs for
clean hydrogen is a particular
challenge. Described in the following
sections and in Table 1 are four considerations that can help to reduce
costs in electrolysis processes.
Efficiency. The first consideration is
the improvement of electrolysis efficiency, particularly the reduction of
cell voltage. Resistance comes from
various phenomena, such as oxidation and reduction reactions, proton
transport across the PEM interface
and mass transport, which dictates
water’s access to a catalyst layer.
The cell voltage is the total of the
voltages derived from these resistances. As the PEM is involved in
the proton transport, it is a contributor to total cell voltage, and must be
considered for the reduction of resistance that is needed to improve
electrolysis efficiency.
Durability. The second design consideration to focus on is ensuring
durability that allows for operation
over ten years or more. During water
electrolysis, hydroxyl radicals are
generated through the Fenton reaction of hydrogen peroxide (a side
reaction). Because hydroxyl radicals
have tremendous oxidative reactivity,
PEMs need to have high chemical
stability to give them high durability.
Also, when performing differentialpressure water electrolysis, the PEM
continuously experiences the pressure of the cathode, demanding high
mechanical strength.
Safety. The third crucial characteristic to think about is safety. In highpressure water electrolysis, hydrogen permeates the PEM and mixes
with oxygen. The lower explosive
limit (LEL) of hydrogen is 4 vol. %.
Therefore, it is necessary to enhance
the hydrogen-shielding ability and
the mitigation ability of the permeated hydrogen. Hydrogen shielding refers to the technically usable
amount of hydrogen per the theoretical amount of generated hydrogen.
The mitigation ability is the mitigated
amount of permeated hydrogen per
the amount of permeated hydrogen
32
Electrolysis
efficiency
Durability
Safety
PEM resistance,
hydrogen shielding
ability
Chemical stability,
mechanical strength
Hydrogen shielding
ability, hydrogen
mitigation ability
without a mitigation strategy, such as
a gas recombination catalyst (GRC).
More details on GRC technologies
are described later in this article.
Compatibility. The fourth characteristic is process compatibility.
Normally, dry PEMs swell three-dimensionally when hydrated. In-plane
expansion significantly affects the
yield and quality of PEM manufacturing and subsequent processes.
Therefore, high dimensional stability
in the in-plane direction is required.
To realize these four characteristics,
trade-offs must be considered. For
example, reducing PEM thickness is
an effective method to reduce membrane resistance, but it is impossible
to avoid a decrease in safety due to
an increase in the amount of permeated hydrogen. Therefore, developing
membrane-design strategies that reduce the need for such trade-offs is a
high priority.
PFSA polymers
A perfluorinated sulfonic-acid (PFSA)
polymer is the most commonly used
polymer for PEMs in water electrolysis applications, and a representative PFSA polymer is shown in Figure
2. This type of polymer is obtained
through the copolymerization of tetrafluoroethylene and perfluoroethylene with a sulfonic acid group. Due
to their perfluorinated structure, PFSA
materials have high chemical stability.
Furthermore, the hydrophobic
main chain (with a polytetrafluoro
ethylene structure), and the hydrophilic side chain (with a sulfonic acid
Process
compatibility
Dimensional stability
when hydrated
group), form a phase-separated
structure, creating an ion cluster
where sulfonic acid groups are accumulated [6]. A structure of ion clusters has been proposed to be linked
with narrow channels by Gierke [7],
which is a probable reason for the
high proton conductivity of perfluorinated sulfonic acid polymers
(Figure 3) [6–8].
Proton conductivity is known to depend on the number of sulfonic acid
groups. The ion-exchange capacity
(IEC; typical units: meq/g) is an index
that represents the amount of sulfonic
acid (meq) per unit weight (g) of a polymer. For a PFSA polymer synthesized
by changing the copolymerization
ratio, the membrane resistance, as
well as IEC, can be tuned. The higher
the IEC is, the lower the distance between ion clusters is, which is a probable reason that polymers with high
IEC values also exhibit high proton
conductivity [8, 9]. In addition, the IEC
and molecular structure of the polymer
also affect hydrogen permeability and
mechanical strength. Perfluorinated
sulfonic acid polymer has been used
in various applications, such as chloralkali electrolysis and fuel cells because of these characteristics.
PEM design strategy
The following paragraphs describe
several design techniques for PEMs
that can help realize the four required characteristics for efficient
water electrolysis.
A PEM consists of polymer, reinforcing materials and additives. One
FIGURE 2. A molecular structure of a representative perfluorinated sulfonic acid (PFSA) polymer is shown
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
PEMs typically
expand when hydrated. In-plane
expansion
can
not only worsen
the yield of membrane production
and subsequent
processes, but is
also believed to
impact electrolysis performance.
Reinforcement
can be applied to
suppress the rate
FIGURE 3. Perfluorinated sulfonic-acid polymers exhibit high proton conduc- of
dimensional
tivity, which is thought to be caused by the formation of ion clusters [7 ], as
change
in the inshown here
plane
direction.
Polytetrafluoromethod to improve electrolysis effi- ethylene (PTFE) has been used as
ciency is to use a polymer with a high a reinforcement material, enabling
IEC. Reducing membrane thickness dramatic reductions in the rate of
is also an effective method to re- dimensional change.
duce membrane resistance, but beAs described previously, PEMs
cause hydrogen-shielding ability de- can be improved with a combinacreases, there is a trade-off between tion of the proper polymers, addiimproving electrolysis efficiency and tives and reinforcing materials, along
safety. A technique to minimize the with meticulous attention to design.
impact of this compromise is the use However, trade-offs and safety
of a GRC, which is a catalyst addi- should be considered when optitive that converts the hydrogen that mizing the materials to achieve the
has permeated through a PEM into target performance.
water via a reaction with oxygen.
Further progress in PEM design
This technique allows for a dra- technology is required to balance the
matic reduction in the concentration four required characteristics for efof hydrogen in the anode, enabling fective water electrolysis discussed
differential high-pressure water elec- previously — efficiency, durability,
trolysis under safe conditions. Plati- safety and compatibility. Additionally,
num is known as an effective GRC the performance of PEMs is greatly
[10]. By applying a GRC and mem- influenced by other factors, such
brane thinning, it is possible to im- as the catalyst and catalyst-disperprove hydrogen shielding ability and sion ionomers, GDL, flow field and
electrolysis efficiency.
heat control.
■
There is also a need to enhance the
Edited by Mary Page Bailey
chemical stability of PEMs to withstand the presence of hydroxyl radi- Acknowledgement
cals generated during water electroly- Images provided by authors
sis. A radical scavenger is a chemical
species as an additive to reduce the For more information, please contact
amount of hydroxyl radicals by con- Shunsuke Tsukuemoto at shunsuke.
verting the radical into a chemically tsukuemoto@agc.com
inert compound, which can suppress
the decomposition of polymer. In fuel References
cells, inorganic compounds, such 1. K. Ayers, N. Danilovic, R. Ouimet, M. Carmo, B. Pivovar, and M.
Bornstein, Annu. Rev. Chem. Biomol. Eng.,10, 219 2019.
as cerium, manganese, chromium, 2. S. Hayabe, H. Okada, and T. Sawada, J. Fuel Cell Sci. Technol.,
23, 30, 2024.
cobalt and aluminum have been reHayabe and K. Sumikura, J. Fuel Cell Sci. Technol., 20, 36,
alized to act an effective radical scav- 3. S. 2021.
enger, although some compounds 4. M. Nur, I. Salehmin, T. Husaini, J. Goh, and A. B. Sulong, Energy
Convers. Manag., 268, 115985, 2022.
have a problem of leaching out during
5. S. Hayabe, K. Sumikura, and M. Ohkura, Chem. Eng.,
power generation [11].
40–42, 2021.
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
6. K. A. Mauritz and R. B. Moore, Chem. Rev., 104, 4535, 2004.
7. T. D. Gierke, G. E. Munn, and F. C. Wilson, J. Polym. Sci.: Polym.
Phys. Ed., 19, 1687, 1981.
8. S. Hayabe, T. Okuyama, K. Sumikura, and T. Nishio, Hydrogen Production Technologies by Water Electrolysis – Basics and stateof-the-art technologies of various water electrolysis methods,
and trends of global hydrogen policies, Tokyo: CMC Research,
Ltd., 69-74, 2023.
9. A. Kusoglu and A. Z. Weber, Chem. Rev., 117, 987, 2017.
10. C. Klose, P. Trinke, T. Böhm, B. Bensmann, S. Vierrath, R. HankeRauschenbach, and S. Thiele, J. Electrochem. Soc., 165,
F127, 2018.
11. Z. Rui and J. Liu, Prog. Nat. Sci.: Mater. Int., 30, 732, 2020.
Authors
Yusuke Chiba is a researcher at
AGC, Inc.’s chemicals company.
Working on the development of
ion-exchange membranes since
2023, his responsibilities include
designing ion-exchange membrane technologies and evaluating
their electrolysis performance. He
holds a Ph.D. in engineering from
Kyoto University, where he studied
supramolecular chemistry and organic synthesis.
Shintaro Hayabe is a researcher
at AGC, Inc.’s chemicals company,
where he has worked since 2017.
He graduated from Keio University
with a M.S. degree in engineering.
He has been working with materials related to ion-exchange membranes for about seven years. His
responsibilities include the development of new ion-exchange
membrane technologies and the evaluation of their
actual performance.
Toshiaki Sawada is a group
leader in the Research & Development Division of AGC, Inc.’s chemicals company, where he has
worked since 2023.He graduated
from Kyoto University with a M.S.
degree in engineering. He has
been working at AGC since 2007
and has been involved in the development of fuel cell materials
and the fluoropolymer film products. His responsibilities
include determining the direction of new ion-exchange
membrane development.
Shunsuke Tsukuemoto is a
sales and marketing manager at
AGC Chemicals Americas, Inc.
(AGCCA) and has worked there
since 2023. In his current role, he
is responsible for sales and marketing of ion-exchange membranes and ionomer solutions. He
holds a B.S. degree in economics
from Keio University.
Will Salem is a technical manager at AGC Chemicals Americas,
Inc. (AGCCA) and has worked
there since 2018. In his current
role, he is responsible for AGCCA’s
technical service and product development of ion-exchange technologies. He holds a B.S. in materials science and engineering from
Pennsylvania State University.
33
Engineering Practice
Make the Most of Alarms
As processes have become more complex and dynamic, alarm management
software has evolved, and now provides deep intelligence to keep plant personnel
safer, more aware and more efficient
Dustin Beebe
Emerson
T
here can be little doubt that
effective alarms are one of
the most critical elements of
safe, high-efficiency operations. Alarms not only keep people
safe by alerting operators when a
process has moved outside of its
defined boundaries, they are also a
critical check on the steps of an operation to ensure consistent manufacture of only the highest-quality
product. While designing, building
and implementing an effective alarm
strategy has never been easy, the
complexity of this effort increased
dramatically with the introduction of
digital control systems.
One of the key benefits of modern
digital control systems is flexibility,
and that flexibility extends to the creation of alarms. Whenever anything
goes wrong with operations, a user
can quickly step in and create an
alarm to ensure they have more visibility to that problem in the future.
However, the ease with which users
can add alarms often leads to an
overwhelmingly complex array of different alarms, which in turn complicates and confuses operators both
as they run the plant, and when they
try to manage the alarms in the system. Users can often create, propagate and change alarms faster than
documentation can keep up.
The ability to propagate alarms
faster than they are documented is
a serious hinderance in today’s world
of complex, multi-state processes. In
very little time, an operations team can
make changes on top of changes to
the alarm database, and when there
is a process upset or a change of
process state, operators are flooded
with thousands of alarms in seconds
— far more than any human can
34
handle. Not only are
alarm floods stressful to the operator,
they also mask real
problems in a torrent
of non-issue alarms.
Implementing
alarm management
is the key to bringing alarms under
control.
However,
not all alarm man- FIGURE 1. Modern alarm management software incorporates new tools,
agement solutions including artificial intelligence, to help operators make better decisions.
are created equal. With modern alarm management software, alarm changes are made online,
the complexity and hassle of manually transferring changes to
Manual alarm man- eliminating
the control system
agement is cumberable format. All these steps presome and complex,
and often leads to stalled projects. ceded the actual rationalization.
After the spreadsheets were creAlarm management software can
help, but only if it is designed for ated and organized, teams of engiworking with modern control and neers would typically spend months
supervisory control and data acqui- trying to rationalize the alarms and
adjust the spreadsheets accordsition (SCADA) systems.
Fortunately, today’s best-in-class ingly. On average, this process realarm management software solu- quired the team to make 1,000 to
tions are designed to dramatically 2,000 changes to bring alarms in
reduce the time and effort of con- line for a typical process plant. Morefiguring and maintaining alarm man- over, as each of these changes was
agement. As those solutions evolve made, any documentation needed
with emerging tools like artificial intel- to be performed manually for each
ligence (AI), they will continue to im- instance — an extremely time-conprove in the coming years, eventually suming process that was often igbecoming autonomous copilots that nored or overlooked.
Today, many of the steps of ratiohelp operators manage their processes far more safely and efficiently nalization are performed using a software solution, which makes it easier
(Figure 1).
to eliminate mistakes. However, not
Alarm management failures
all software solutions are created
Traditional alarm rationalization — equal. Many alarm management sowithout the aid of software — re- lutions require users to perform all
quired engineers to export all the rationalization offline, and then apply
control system configuration into changes manually. Doing so is time
files. The team would then need consuming, complex, prone to error
to manipulate those data to enable and makes change management difthe data to be moved to a spread- ficult to implement and follow. As a
sheet. Once the data set was in a result, most current alarm managespreadsheet, it would need to be ment projects fail not because the
organized to ensure it was in a us- team did not complete rationalizaCHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
ment software dramatically reduces
the time engineers
spend updating the
control system with
new alarm parameters. Such solutions
empower teams to
perform
rationalization online while
connected to the
control system.
FIGURE 2. Dynamic alarming takes the process state into account to help
With an inteensure alarms are delivered when they are needed
grated alarm mantion, but because once they finish, agement solution, alarms can be
they have so many changes to man- modified one by one, or in bulk. As
ually enter into the control system each change is made, the user can
that they never complete the job.
see the control system configuraFirst and foremost, it is difficult to tion and establish process bounddecide how to get the changes back aries linked directly to assets, and
into the control system and who will then easily record that change in the
do it. Often, weeks or months go by documentation. If an asset or alarm
with some changes implemented changes at a later date, the team
and others not, and the team never can see what assets were impacted
truly knows what has changed. In by that change, and it can audit the
the meantime, processes change, change against the boundaries.
and new alarm edits are made on
Most importantly, once the team
top of previous changes. Ultimately, has made its changes in an intethe team can never catch up.
grated alarm management soluEven if the team does success- tion, they simply click a button
fully complete rationalization with and all changes are applied to the
an offline software tool, maintain- control system. The ability to apply
ing those changes becomes a her- changes online saves significant
culean task. In the coming months time and effort. For example, a
or years, the plant will likely have large integrated chemical site can
equipment changeouts, or neces- make about 30,000 parameter
sary process changes.
changes per month to their conIf all alarm rationalization is per- trol system, many of which impact
formed offline, it becomes increas- or are related to alarms. It would
ingly difficult to keep up as more be nearly impossible for that proand more changes are applied. cess manufacturer to keep up with
Each change must be recorded of- those changes without an intefline, and then applied manually to grated software solution. But with
the control system. Moreover, if a the right software, the team can
year later the team wants to know instantly see the last-read value
if the alarm system is still valid, they when a change was made, what
need to go through the process was approved, who approved it
of exporting data and comparing and why, and the initial reason the
again — a process that will likely alarm was created. This type of
take weeks or months.
database allows the team to document and audit those control sysIntegrated software
tem changes quickly and easily.
To avoid the complexity of transferring offline changes to the control Changes increase complexity
system manually, many of today’s Historically, when engineers would
forward-thinking organizations are design alarms for a control system,
leveraging alarm management soft- they would ask themselves three key
ware that is integrated with their questions:
control system by design. Seam• What alarm does the plant need?
lessly integrated alarm-manage• What is the purpose of this alarm?
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
• What priority should be given to
the alarm?
However, even after asking those
questions, many struggle with alarm
floods during transition periods like
startups, upsets and shutdowns.
Transitional alarm floods contribute
to incidents, and this issue is exacerbated because incidents are more
likely to occur during transitions than
in periods of normal operation. With
just one additional question, it becomes significantly easier to eliminate these alarm floods:
• When does the plant need this
alarm?
Modern alarm management must
accommodate dynamic process
states. For example, consider a flow
alarm on a heater. When the heater
is operational, low pass flow through
a tube would be a serious concern.
Over time, the tube with the low
pass flow would warp and eventually create a loss of process containment, and material from the process
would pour directly into the heater.
Hypothetically, the process could be
shut down for weeks and cost the
organization millions of dollars. As
a result, when the heater is operational, it is essential to receive low
pass flow alarms.
However, sometimes the heater
will be shut down, but if the process
unit does not have dynamic alarm
management, the alarm system will
not know the difference. If the heater
has 16 pass flows, the operator will
receive 16 alarms, even though this
is the expected state during shutdown. Those alarms will fill up a
page and push many alarms onto
another page. The low pass flow
may be a high priority alarm, but it is
meaningless in the shutdown operating mode.
While during shutdown, such a
problem might be frustrating, during startup it becomes dangerous.
During startup, operators are putting mass and energy into the process and hoping that this is occurring within specification. However,
the low pass flow alarm that was
activated while the heater was shut
down (potentially several weeks
ago) is still a standing alarm and is
now valid because the operator has
moved the process into an opera35
the team transitioned
to the startup state,
if pass flow was
blocked, the system
would recognize that
in the current state
the alarm was valid,
and it would be delivered to the operator at the appropriate
time. This technology
would improve visibility and increase
FIGURE 3. The most effective alarm management software helps teams
the safety of the opidentify places where their alarm strategy can be streamlined for increased operator awareness
eration, regardless of
how many times the
tional state. As far as the control sys- process state changed.
tem is concerned, it has notified the
operator, even though that notifica- The future of alarming is AI
tion came a long time ago and may Alarm management is not a set-andbe on page 20 of the alarm screen. forget process. No matter where
The system does not know the alarm they are in their alarm management
was not valid before, so it will not journey, organizations should always
re-alert the operator. Operators are be updating and improving the perrequired to maintain an incredibly formance of their alarm strategy.
high level of vigilance to track such However, in an era of worker shortaberrations across extended time ages and increased efficiency and
periods, and mistakes are far more sustainability goals, finding the time
likely to occur.
and personnel to continuously manIn fact, most failures occur on age alarms can be difficult.
startup because operators are efToday’s most effective alarm-manfectively working without alarms. agement-software solutions help
The alarm is on their screen and teams manage the complexity of
they are expected to know about alarms. Operators using these tools
it, but often that means scanning log in and can immediately see the
hundreds of alarms across multiple top ten alarms in a report, and they
pages to identify if it is still valid. can then click through those alarms
Doing so is not impossible, but it is to receive recommendations of ways
a recipe for disaster.
to intervene and improve the operational state. Moreover, these same
Dynamic alarming
tools can make basic recommendaDynamic alarm management helps tions to improve the configuration
eliminate the alarms that occur as a of the alarm software itself. Teams
result of changing operational states. can receive notifications of chatterEngineers simply design the state ing alarms and suggestions of alarm
logic — for example, run, upset, bands they should change to reduce
shutdown and startup — and cate- that chattering. Advanced software
gorize each alarm by one or more of can also help teams recognize and
those states. The transition technol- remedy redundant alarms to help
ogy in the most advanced dynamic avoid unnecessary alarms (Figure 3).
alarm software enables the operaIn the near future, these same
tors to seamlessly move between solutions will begin to add more
states without creating custom logic autonomous operation, with AI enfor each alarm (Figure 2).
gines working alongside operators
In the heater example above, the to help identify which alarms are
pass flow alarm would be identified useful, and which are less so, and to
by the alarm system as not appli- recommend changes to engineers
cable during the shutdown state, to streamline the alarm database.
so the operator would receive zero These tools will further shorten the
alarms instead of 16. Then, when time required for alarm rationaliza36
CHEMICAL ENGINEERING
tion, with AI copilots that continuously identify opportunities for improvement by recommending alarm
settings and changes to boundary
levels. Engineers can review and
approve these suggestions, spending two minutes instead of twenty to
create or improve each alarm.
Moreover, AI tools will also help
teams ensure documentation is as
thorough, accurate and standardized as possible. Much like today’s
text message and word processing
tools, AI can be applied to evaluate
documentation as it is being written,
recommending additions or formatting to help ensure all documentation
is easy to read and reference.
Building for the future, today
Alarm management is a safety issue.
Often, the fallout from poor alarming
is not obvious until a disaster strikes,
and as processes get more complex,
the ability to manage alarms so they
keep operators alert and do not cause
confusion will only become more critical. It is so critical, in fact, that countries around the world are beginning
to legislate alarm standards.
Not only do the foundational technologies exist to dramatically improve alarm management, they are
also typically easy to install and use.
Plants that invest today in a foundation of integrated, dynamic alarm
management software will not only
reap significant safety and operational
efficiency benefits today, they will also
position themselves to take advantage of the emerging AI technologies
that will soon redefine and improve
how plants operate.
■
Edited by Dorothy Lozowski
Acknowledgement
All figures courtesy of Emerson
Author
Dustin Beebe is the Vice President of Performance Software at
Emerson (Baton Rouge, La.; Email:
Dustin.Beebe@emerson.com). He
is responsible for the alignment of
the Control Performance, Operator
Performance, and Simulation businesses globally and the strategy
synergy between Emerson and
AspenTech. Prior to joining Emerson, Beebe served as the President of ProSys until it was
acquired by Emerson in 2018. He has been in the industrial automation business since 1996. Beebe holds a
B.S.Ch.E degree from the University of Arkansas in Fayetteville, Arkansas.
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Environmental Manager
Fire and Explosion Safety: Going Beyond
Traditional Protection
A sophisticated approach to fire and explosion safety requires one that expands
conventional protection strategies to comprehensively consider storage, containment
and tool compatibility
Steve Eyer
DENIOS U.S.
I
ndustrial fires and explosions
are a serious risk to chemical
processing facilities worldwide,
threatening significant harm to
personnel, assets and the environment. Despite advancements in
safety practices, root causes continue to pose persistent challenges.
Managing these hazards means addressing volatile chemicals, ignition
sources and the safety demands of
modern processes.
This article examines risks, explores essential safety measures
and provides actionable insights for
improving fire and explosion safety,
with special focus on storage considerations for flammable, combustible or otherwise hazardous materials (Figure 1).
Keeping facilities up to date
Complexity in the chemical processing industries (CPI) is increasing due to process intensification,
automation and the introduction of
novel chemical pathways. Modern
facilities must evaluate and upgrade
their safety infrastructure regularly,
including advanced containment
systems, intentional storage solutions, advanced tools and integrated
safety operations.
Facility updates occur within a
comprehensive regulatory framework that includes the Process
Safety Management (PSM) standard put forth by the U.S. Occupational Safety and Health Administration (OSHA; www.osha.gov),
the Risk Management Program
(RMP) requirements developed by
the U.S. Environmental Protection
Agency (EPA; www.epa.gov), and
international standards such as the
European Union’s ATEX directives.
CHEMICAL ENGINEERING
In Canada, the
Process Safety
Management
standard generally aligns closely
with the PSM
standard
from
OSHA. Globally,
the International
Labor Organization’s (ILO; www.
ilo.org) Chemicals
Convention has
been ratified by
many countries to
establish guidelines for the safe
use of chemicals.
Ensuring compliance with these
regulations demands an inteFIGURE 1. When developing site-safety plans to mitigate the risks of handling
grated approach, flammable materials, storage considerations should never be overlooked
beginning
with
proper material
classification and extending through lies in their ignition temperatures, a
storage, handling and emergency- key part of safe handling and storage. Flammable materials — those
response protocols.
with flash points below 100°F
Classifying material hazards
(37.8°C) — demand the most strinEffective fire and explosion safety gent storage and handling protostarts with understanding the spe- cols. Examples include solvents
cific hazards in a facility. Safety data- and petroleum-based liquids comsheets (SDS/CAS) provide critical monly used in chemical processinformation on a substance’s flam- ing facilities. Combustible materimability, reactivity and toxicity, along als —with flash points between
with handling, storage and disposal 100°F and 200°F — require difguidelines. They also specify per- ferent, but equally specific, safety
sonal protective equipment (PPE) measures. Examples of combusrequirements, safety precautions tible materials often include hyand emergency response mea- draulic fluids and lubricating oils.
sures. Chemical processing facilities Bio-based hydraulic fluids offer an
rely on SDS details to inform stor- added safety advantage because
age infrastructure and emergency- they generally have a higher flash
response plans, ensuring proper point than petroleum-based alterhazard management.
natives. The classification of mateThe distinction between flam- rials as flammable or combustible
mable and combustible materials determines storage requirements
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
37
dard designed to regulate the
storage of flammable liquids in
fire-safe cabinets — minimizing
vapor emissions, containing
potential leaks and protecting
materials during fires. For highly
flammable liquids and vapors
(often designated as H224
substances), regulations mandate 90-minute fire-protection
ratings to prevent them from
becoming ignition sources or
contributing to a fire’s spread.
Fire cabinets control vapor
buildup, contain leaks and protect stored materials during
fires. Their advanced design
ensures compliance with strict
regulatory standards and provides reliable safety. Integrated
ventilation systems prevent
dangerous vapor buildup to
FIGURE 2. Fire-resistant storage cabinets can provide
maintain a safe environment.
multiple features to help sites comply with safe-storage
The cabinets serve as containregulations, including integrated ventilation systems and
ment solutions and act as vital
insulation layers
components of facility-wide
and influences facility layout, emerfire protection.
gency response planning and
One of the primary advantages of
operational procedures.
fire-safe cabinets is their two-way
When determining storage re- protection. These cabinets protect
quirements for hazardous ma- the facility from fires that may origiterials, facilities should consider nate within the cabinet itself while
factors such as physical state, po- also safeguarding the cabinet contential incompatibilities, ventilation tents from external fires. In case of
needs and temperature sensitivity. a fire inside the cabinet, the insulaVapor pressure characteristics, tion layers and automatic door clochemical stability and potential re- sures can hold the blaze for up to
activity are also important. These 90 minutes, providing crucial time
properties inform decisions about for evacuation and emergency reengineering controls, including sponse. This dual protection sigventilation systems, temperature nificantly reduces the likelihood of
regulation and material compat- a minor incident escalating into a
ibility. Modern facilities that handle devastating event.
multiple hazard classes simultaFire-safe cabinets can incorponeously will require advanced ap- rate several features that distinguish
proaches to segregation and stor- them from standard steel cabinets.
age. A thorough assessment from These features include the followa skilled supplier is useful to sup- ing:
port a facility with risk-mitigation • 90-minute fire-protection ratstrategies.
ings in accordance with EN
14470-1 and NFPA standards, proEffective storage solutions
viding maximum safety for highly
Effective fire and explosion safety flammable liquids
relies on storage solutions that inte- • Automatic door closures that
grate multiple safety features. Fire- engage when temperatures rise,
resistant storage cabinets (Figure 2) sealing off the contents
are a prime example, incorporating • Technical
ventilation
sysinsulating layers, automatic door tems that prevent dangerous
closures and technical ventilation vapor accumulation and ensure
systems. These features achieve constant airflow
three critical objectives proposed • Integrated
spill-containment
by EN 14470-1, the European stan- trays to manage leaks and prevent
38
CHEMICAL ENGINEERING
the spread of hazardous materials
• Insulating layers that offer high
fire resistance and slow the heat
transfer into or out of the cabinet,
preserving stored materials and
keeping facilities safe
Cabinet selection
Despite the clear benefits, common
mistakes when selecting fire-safe
cabinets sometimes undermine
safety efforts. One frequent error is
choosing cabinets based solely on
cost rather than protection needs.
Cabinets with lower fire-resistance
ratings, such as the 30-minute
models, may seem appealing due
to their lower price, but they are
not suitable for storing highly flammable substances (H224) and may
not meet the regulations of the local
authority having jurisdiction (LAHJ).
Companies that opt for cheaper,
non-fire-rated steel cabinets often
do so because they believe their
operations involve only small quantities of flammable materials under
exempt amounts.
Another mistake is failing to recognize that fire-resistant cabinets
are not just about internal fires.
Their primary purpose is to delay
external fires from reaching the
hazardous contents inside, giving workers more time to evacuate and first responders more
time to contain the blaze. Some
facilities mistakenly believe their
overall fire-protection measures
are sufficient without cabinet-level
protection, not realizing that improper storage can lead to rapid
fire escalation and potentially
catastrophic damage.
Misunderstanding
certification standards also leads to noncompliant purchases. Fire-safe
cabinets tested to EN 14470-1 or
NFPA 30 standards provide reliable protection, while uncertified
steel cabinets do not offer the
same protection. Facilities that
buy uncertified cabinets may find
themselves unable to meet legal
installation requirements or obtain
insurance coverage. Finally, overlooking installation conditions is a
recurrent issue. Cabinets without
fire protection face strict placement restrictions, often requiring
structural fire-protection measures
and designated explosion-proof
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
signed for situations
requiring
direct
handling
of materials.
To protect all
personnel, these
buildings feature
enhanced safety
measures like advanced fire protection,
special
spill-containment
trays and dedicated dispensing
areas. Because
FIGURE 3. For larger-scale storage capacity of flammable materials, fireworkers
must
rated buildings can be installed onsite to help meet safety standards. Such
enter the storstructures can be designed for indoor or outdoor use
age space, walkzones. In contrast, 90-minute firein facilities meet
rated cabinets offer greater flexibil- higher safety standards than nonity and allow for placement directly occupancy buildings. While non-ocin workspaces. They also reduce cupancy buildings focus on protecttransport times and improve op- ing materials and the surrounding
erational efficiency.
environment, walk-in designs prioriUnderstanding the full scope of tize worker safety due to the higher
fire-safe cabinet functions, features, risk of exposure.
and potential pitfalls helps chemical
When selecting a fire-rated buildprocessing facilities make informed ing, there are some key things to
choices to prioritize safety, ensure consider. Fire ratings give informacompliance and safeguard both tion on a structure’s ability to propeople and property.
vide protection. Many buildings are
designed to provide two-hour fire
Fire-rated buildings
protection or more, depending on
Fire-rated buildings, containers and setback distances. Segregating
lockers manage large-scale hazard- incompatible materials increases
ous-substance storage (Figure 3). safety and involves the use of physiDesigned to meet stringent safety cal barriers or separate compartstandards and to be used indoors ments that prevent hazardous reor outdoors, fire-rated buildings offer actions. Spill containment systems
robust fire protection, secondary spill can provide added back up procontainment and controlled environ- tection. They must accommodate
ments for hazardous materials. They 10% of the total stored volume
come in two primary types: non- or 100% of the largest container,
occupancy buildings and walk-in whichever is greater, to manage
storage facilities.
leaks and prevent the spread of
Non-occupancy buildings are hazardous substances.
designed to minimize personnel
Ventilation systems are fundamenexposure during storage and re- tal to managing hazardous vapors
trieval. They feature full-face open- and supporting a safe atmosphere.
ing doors to allow forklift access For temperature-sensitive chemiand simplify movement of large cals, climate-controlled options encontainers, such as drums or in- sure that materials remain stable, retermediate bulk containers (IBCs). ducing the likelihood of spontaneous
These buildings can be strategi- ignition or decomposition. Fire-rated
cally placed indoors or outdoors buildings are designed to address
and often include climate-control many regulations, such as OSHA,
options for temperature-sensitive EPA and NFPA standards, to ensure
materials. Non-occupancy designs compliance and operational safety.
prioritize efficiency and safety by These buildings are a helpful part
reducing the need for workers to of site plans designed to securely
enter the storage area.
contain hazardous substances to
Walk-in storage facilities are de- reduce risk.
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Lithium battery safety
Lithium batteries pose a risk of fire
and pressure release if not handled
or stored correctly. When mishandled, these batteries can overheat,
catch fire or release pressure, leading to costly damage and potential
harm to workers. Understanding
the hazards, using proper storage
solutions and having the right tools
can all contribute to fire prevention.
A primary danger associated
with lithium batteries is thermal
runaway. Thermal runaway occurs
when cells overheat from thermal
stress, damage or defects. Such
occurrences can produce intense
heat, flammable gases and oxygen, which can lead to fires. In
some cases, electrolyte fluid vaporizes, creating more combustible gases that can ignite and
make the fire worse. Deep discharge is another risk. If batteries
discharge completely and are then
recharged, the electrolyte fluid can
break down, generating flammable
gases and increasing the likelihood
of a fire. Mechanical damage, such
as drops, collisions or deformations, can also cause internal short
circuits and fires.
To mitigate these risks, facilities should use fire-rated storage
buildings or cabinets specifically
designed for lithium batteries.
These provide fire resistance from
both inside and outside, which allows more time to contain a fire
and evacuate the area. They are
equipped with liquid-tight spill
sumps to contain leaks from defective batteries and smoke extraction ventilation systems to manage
to reduce heat and gas buildup.
Fire-rated storage buildings offer
expanded capacity and enhanced
features, such as pressure-relief
and climate-controlled options.
There are effective emergencyresponse tools for dealing with
battery fires. Since these fires generate their own oxygen, traditional
fire extinguishers aren’t effective.
Instead, facilities should stock specialized suppression powders or
granules designed to combat Class
D fires involving burning metals.
These granules work by displacing oxygen, absorbing heat and
forming a barrier to prevent further
combustion. In addition, damaged
39
smother the
flames and
prevent any
re-ignition.
Emergency
showers and
eyewash stations should
be
readily
accessible
with
clear
access paths
from storage
areas.
Ventilation
FIGURE 4. In some applications, specialized tools must be used to further reduce
fire and explosion risks. Such tools are designed so that no sparks are formed dur- systems play
a vital role as
ing maintenance or repair tasks
they
manor defective batteries should be age both routine emissions and
stored in quarantine containers until potential emergency scenarios.
they can be professionally disposed Technical ventilation requirements
of. Combined with proper handling, vary based on stored materials but
these solutions help reduce fire and typically include both high-level
explosion risks from batteries.
and low-level extraction points to
manage vapors of varying denFacility-wide integration
sities. Modern systems often
Storage solutions must align with add monitoring capabilities that
facility-wide systems for grounding allow users to verify proper airand ventilation. Electrostatic dis- flow and provide early warning of
charge is a major risk during mate- system failures.
rial transfers, so modern facilities
use grounding systems with contin- Specialized tools to reduce risks
uous monitoring. Active grounding In chemical processing facilities,
systems with LED indicators allow flammable gases, vapors and dust
quick connection verification. For make the risk of ignition ever-preshighly flammable materials or com- ent. Preventing sparks during roubustible dust, this provides better tine maintenance or emergency
protection than passive methods, repairs is necessary for fire and exespecially during transfers.
plosion safety. Non-sparking tools
The effectiveness of storage sys- are designed for hazardous environtems also depends on how well they ments like these (Figure 4).
work with emergency-response
Non-sparking tools are made from
capabilities. Strategic placement non-ferrous metals, such as aluensures emergency access while minum bronze, phosphor bronze,
supporting safe separation dis- beryllium copper and brass. These
tances. Some materials, including materials do not produce sparks
volatile dusts, require specialized when struck or rubbed against other
extinguishing agents, so fire sup- surfaces, which reduces the chance
pression systems should match the of ignition in environments where a
specific hazards present. For exam- single spark could cause an explople, Class D fire extinguishers may sion. These tools are indispensable
be necessary for combustible metal for working around flammable subdusts like aluminum or magnesium. stances like solvents, gases and
Carbon dioxide systems are often combustible dust.
Beyond spark prevention, nonused for extinguishing fires involving
flammable solvents or chemicals sparking tools are often corrosionwhere water could cause a hazard- resistant, making them suitable for
ous reaction. Foam suppression environments where chemicals,
systems are needed for handling moisture or extreme conditions
fires involving large quantities of could degrade standard tools. Their
flammable liquids, such as toluene durability ensures effectiveness in
or acetone, because they help harsh chemical or humid conditions.
40
CHEMICAL ENGINEERING
Non-sparking tools are available in
a variety of forms to support different maintenance needs, including
wrenches, hammers, screwdrivers,
pliers and scrapers. These tools are
designed for safe use in situations
where traditional steel tools pose a
risk. Non-sparking tools help chemical processing facilities reduce the
risk of fires and explosions, making them a part of a comprehensive
prevention strategy.
Continuous improvement
As hazards evolve and new safety
technologies
emerge,
facilities
must upgrade monitoring systems,
enhance containment measures,
and integrate solutions that boost
safety and efficiency. This involves
maintaining documentation, frequent inspections and responsible
equipment management. Comprehensive training programs covering
routine operations and emergency
response are essential to this effort. By building and maintaining
a robust safety system, facilities
can stay compliant, reduce risks
and protect employees, assets
and the environment. Continuous improvement is the foundation of effective fire and explosion
hazard management.
■
Edited by Mary Page Bailey
Acknowledgement
All images provided by author
Author
Steve Eyer is an engineered systems sales manager at the DENIOS U.S. (1152 Industrial Blvd.,
Louisville KY 40219; Phone:
1-800-216-7776; Email: seyer@
denios-us.com.) Eyer has over 25
years of experience within the
safety industry with a focus on
design and engineering of flammable combustible products. He
has worked for many leading manufacturers and is a
three-time patent recipient. Throughout his career, Eyer
has contributed to industry regulations and given influence for engineered judgments to third party insurers.
He holds a mechanical engineering degree from Vincennes University and is currently pursuing his M.S. in
technology from Eastern Illinois University.
Further reading
1. Design for Safety: Tips for Proactive Risk Reduction,
Chem. Eng., Feb. 2023, pp. 30–33.
2. Steps to Improve Safety Challenges in Hazardous
Environments, Chem. Eng., Aug. 2022, pp. 42–46.
3. Process Changes: Understanding and Mitigating
Fire- and Life-Safety Risk Factors, Chem. Eng.,
Sept. 2020, pp. 50–53.
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Dependable and Energy Efficient Direct
Steam Injection Heaters
Process industries demand reliable water heating equipment offering precise temperature control. Pick direct steam injection
heaters satisfy both requirements. Pick’s proven, robust design
provides continuous service with minimal maintenance. Discharge temperature is held to extremely close tolerance – within
1°C or less – while providing rapid yet controlled response to
changing process conditions.
Pick steam injection heaters provide 100% heat transfer efficiency – eliminating flash and heat losses inherent with indirect
exchangers. Pick Heaters are the right choice for:
•
Jacketed Vessel Heating
•
Tank and Equipment Cleaning
•
CIP and Sterilization
•
Batch Filling of Tanks
https://www.pickheaters.com
For details visit adlinks.chemengonline.com/88111-09
Chemical Engineering’s premium
product showcase for the latest
products and technologies in the
chemical processing industries.
to subscribe to the e-letter, please visit:
www.chemengonline.com/eletter-signup
26033
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
41
New & Used Equipment
Software
HEAT EXCHANGERS
Engineering e-material, e-solutions, e-courses
and e-seminars for energy conversion systems:
▼
● Physical Properties
● Steam Approximations
● Power Cycles
● Compressible Flow
● Power Cycle Components/Processes
Liquid Cooled
ENGINEERING SOFTWARE
Phone: (301) 919-9670
Web Site: http://www.engineering-4e.com
Check out free online calcs, demos, etc.
FOR
For details visit
adlinks.chemengonline.com/88111-242
▼
Air Cooled
GASES & LIQUIDS!
Talk Directly with Design Engineers!
Blower Cooling
Vent Condensing
Written for engineers,
by engineers
(952) 933-2559 info@xchanger.com
For details visit
adlinks.chemengonline.com/88111-241
February
2015
ngonline.com
www.cheme
gers:
Heat Exchan Report
Two-Part Feature
Advances
in 3-D Printing
ial
Focus on Industr
Housekeeping
02
Fundamentals
oF HigH-sHear
dispersers
• Heat excHangers
For details visit
adlinks.chemengonline.com/88111-240
Fingertips:
Facts at Your Numbers
Dimensionless
Valves for
Extreme Service
s of
FundamentalDispersers
High-Shear
page 40
To subscribe or
learn more about
membership,
please visit
www.chemengonline.
com/subscribe
Vol. 122 No.
2 february
2015
•
www.chemengonline.com
ADVERTISE IN THE
CLASSIFIEDS
40642 CHE House Ads Resize.indd 1
2/11/22 4:12 PM
Contact your Sales Representative for More Information:
TERRY DAVIS | 404-481-0254
tdavis@chemengonline.com
PETRA TRAUTES| +49 69 58604760
ptrautes@accessintel.com
Advertising Sales Representatives
North America
International
Matthew Grant | VP & Group Publisher
Petra Trautes
Katshuhiro Ishii
mgrant@accessintel.com
Tel: +49-172-6606303
Email: ptrautes@accessintel.com
Access Intelligence International Postfach 20 01 39
D-63307 Roedermark
Tel: 81-3-5691-3335
Fax: 81-3-5691-3336
E-mail: amskatsu@dream.com
Chemical Engineering Ace Media Service Inc., 12-6, 4-chome
Nishiiko, Adachi-ku, Tokyo 121, Japan
Terry Davis | District Sales Manager
Tel: 404-481-0254
E-mail: tdavis@accessintel.com
Chemical Engineering 2276 Eastway Rd., Decatur,
GA 30033
Europe
Connecticut, District Of Columbia, Delaware,
Georgia, Maine, Maryland, Massachusetts,
New Hampshire, New Jersey, New York,
Pennsylvania, Rhode Island, Vermont, Canada,
Latin America
Tel: 917-592-7729
E-mail: ddhar@accessintel.com
Chemical Engineering 40 Wall Street, 16th Floor, New York, NY
10005
Japan
Dipali Dhar
India
Rudy Teng
Tel: +86 13818181202, (China)
+886 921322428 (Taiwan)
Fax: +86 21 54183567
E-mail: rudy.teng@gmail.com
Chemical Engineering 8F-1
#181 Wulin Road Hsinchu 30055 Taiwan
Asia-Pacific, Hong Kong, People’s Republic of China,
Taiwan
42
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
Advertisers Index
Advertiser.............. Page number
Reader Service #
Phone number
Advertiser.............. Page number
Phone number
Reader Service #
Abbe, Paul O...........................26
moeve..................................... 19
1-855-789-9827
adlinks.chemengonline.com/88111-07
adlinks.chemengonline.com/88111-06
Curtiss-Wright...........................3
1-877-537-9120
adlinks.chemengonline.com/88111-02
Dynamic Air.............................29
Myron L Company................... 11
760-438-2021
adlinks.chemengonline.com/88111-04
Pick Heaters............................ 41
adlinks.chemengonline.com/88111-09
adlinks.chemengonline.com/88111-08
HAPMAN............................. CV 2
1-800-427-6260
adlinks.chemengonline.com/88111-01
See bottom of opposite page
for advertising
sales representatives'
contact information
i.safe-MOBILE......................... 15
adlinks.chemengonline.com/88111-05
Plast-o-Matic....................... CV3
973-256-3000
adlinks.chemengonline.com/88111-10
Ross Mixers..............................7
1-800-243-ROSS
adlinks.chemengonline.com/88111-03
MathWorks........................... CV4
adlinks.chemengonline.com/88111-11
Classified Index February 2025
New & Used Equipment...........................................................42
Software...................................................................................42
Advertiser
Page number
Advertiser
Page number
Phone number
Reader Service #
Phone number
Reader Service #
Xchanger
42
Engineering Software
42
301-919-9670
adlinks.chemengonline.com/88111-242
Vesconite Bearings
(952) 933-2559
adlinks.chemengonline.com/88111-241
42
713-574-7255
adlinks.chemengonline.com/88111-240
FOR ADDITIONAL NEWS AS IT DEVELOPS, PLEASE VISIT WWW.CHEMENGONLINE.COM
FEBRUARY 2025; VOL. 132; NO. 2
Chemical Engineering copyright © 2025 (ISSN 0009-2460) is published monthly by Access Intelligence, LLC, 9211 Corporate Blvd., 4th Floor, Rockville, MD 20850. Chemical Engineering Executive, Editorial and Publication Office: 40 Wall Street,
16th Floor, New York, NY 10005. Phone: 212-621-4694. For specific pricing based on location, please contact Client Services, clientservices@accessintel.com, Phone: 1-800-777-5006. Periodical postage paid at Rockville, MD and additional
mailing offices. Postmaster: Send address changes to Chemical Engineering, 9211 Corporate Blvd., 4th Floor, Rockville, MD 20850. Phone: 1-800-777-5006, Fax: 301-309-3847, email: clientservices@accessintel.com. Change of address two to
eight weeks notice requested. For information regards article reprints please contact Wright’s Media, 1-877-652-5295, accessintel@wrightsmedia.com. Contents not be reproduced in any form without permission. Canada Post 40612608. Return
undeliverable Canadian Addresses to: The Mail Group, P.O. Box 25542 London, ON N6C 6B2 Canada.
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
FEBRUARY 2025
43
Economic Indicators
Download the CEPCI two weeks sooner at www.chemengonline.com/pci
CURRENT BUSINESS INDICATORS
LATEST
PREVIOUS
YEAR AGO
CPI output index (2017 = 100)_____________________________________________________
CPI value of output, $ billions _____________________________________________________
CPI operating rate, % ___________________________________________________________
Producer prices, industrial chemicals (1982 = 100) _____________________________________
Nov. '24
Oct. '24
Nov. '24
Nov. '24
=
=
=
=
100.4
2,408.9
76.7
301.3
Oct. '24
Sept. '24
Oct. '24
Oct. '24
=
=
=
=
100.5
2,404.4
77.0
305.9
Sept. '24
Aug. '24
Sept. '24
Sept. '24
=
=
=
=
100.5
2,409.9
77.0
307.0
Nov.. '23
Oct. '23
Nov.. '23
Nov.. '23
=
=
=
=
99.5
2,394.7
77.6
307.0
Industrial Production in Manufacturing (2017 =100)* ____________________________________
Hourly earnings index, chemical & allied products (1992 = 100) _____________________________
Productivity index, chemicals & allied products (1992 = 100)_______________________________
Nov. '24
Oct. '24
Nov. '24
=
=
=
98.4
234.6
93.5
Oct. '24
Sept. '24
Oct. '24
=
=
=
98.2
235.2
93.3
Sept. '24
Aug. '24
Sept. '24
=
=
=
98.9
230.0
94.0
Nov.. '23
Oct. '23
Nov.. '23
=
=
=
99.3
224.0
93.3
2022
2023
CPI OUTPUT INDEX (2017 = 100)†
110
105
100
2024
CPI OUTPUT VALUE ($ BILLIONS)
CPI OPERATING RATE (%)
2500
85
2400
80
2300
75
95
2200
90
70
2100
85
65
2000
80
75
60
1900
J F M A M J
J A S O N D
J F M A M J
J A S O N D
J F M A M J
J A S O N D
*Due to discontinuance, the Index of Industrial Activity has been replaced by the Industrial Production in Manufacturing index from the U.S. Federal Reserve Board.
†For the current month’s CPI output index values, the base year was changed from 2012 to 2017
Current business indicators provided by S&P Global Market Intelligence, New York, N.Y.
The Chemical Engineering Plant Cost Index® can now be found on our website at
www.chemengonline.com/economic-indicators
Enhance Your Plant Cost Estimates with
Chemical Engineering’s Plant Cost Index®!
Sep ‘06
Prelim.
Aug ‘06
Final
Sep ‘05
Final
CE Index
513.1
510.0
467.2
Equipment
606.5
602.3
541.2
Heat Exchanges and Tanks
565.1
560.9
509.2
Process Machinery
559.6
556.2
521.7
Pipe, valves and fittings
734.7
731.7
620.8
Process Instruments
441.4
437.2
379.5
Pumps and Compressions
788.9
788.3
756.3
Electrical equipment
418.9
414.2
374.6
Structural supports
643.7
637.7
579.3
Construction Labor
314.7
312.9
309.1
Buildings
476.9
475.2
444.7
Engineering Supervision
350.7
351.9
346.9
510
500
490
480
470
460
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Subscribe now chemengonline.com/pci-home
44
45550 CE PCI House Ad_6.875x4.25.indd 1
CHEMICAL ENGINEERING
WWW.CHEMENGONLINE.COM
7/26/24 11:02
AM
FEBRUARY
2025
For details visit adlinks.chemengonline.com/88111-10
MATLAB
FOR AI
Boost system design and simulation with explainable and
scalable AI. With MATLAB and Simulink, you can easily train
and deploy AI models.
© The MathWorks, Inc.
mathworks.com/ai
For details visit adlinks.chemengonline.com/88111-11