The Industrial Manufacture of Chemical Compounds

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The Industrial Manufacture
of Chemical Compounds
Step-Up
Introduction
• Welcome!
• Personal Introduction
• What today’s topic will cover…
Contents
• What factors do we need to consider
in design of a plant?
• Types of industrial processes
• What factors are important in
running a plant?
Key design factors
• What do we want to make?
• In what quantities? (cost constraints / demand
constraints, competition already in this market)
• How will we manufacture? (Differences in
processes)
• Where do we locate the facility?
• How can we ensure safe production?
• What environmental /local or national legislation
considerations are there?
• What are the costs associated with start up?
• What systems will be used to operate the facility
(people and shifts)?
What and how much do we
want to make?
• Will this plant make only one product or
many products?
– Examples are sulphuric acid, sodium
hydroxide, dyestuffs, perfumes
• How much will we make?
– 10g, 10kgs or 10,000T
The answers to these questions will
determine how we will manufacture
Key Business Decision
• How are we going to make the
product?
- We need ‘Know-how’
- We need a production ‘blueprint’
- We need to decide on the
equipment that is is needed
- We need a strategy – decide on our
method of making the product
Examples of Processes
• Single unit production process –
Single Job production e.g.
manufacture of a hand-made
detailed /complex piece of furniture
• Mass production – using machines
and people to repeat simple
production tasks to quickly build
many of the same products e.g.Cars
Manufacturing processes
• Batch process - A process that is not in
continuous or mass production;
operations are carried out with discrete
quantities of material or a limited number
of items (1T of X and 2T of Y)
• Continuous process -Industrial process
that continuously receives raw materials
and processes them through to
completed units (1T/h of X and 2T/h of Y)
Batch Production
Continuous Processing
Manufacture of Aspirin –
batch process
Pronunciations:
Salicylic:Sally-sillic
Examples of batch
processes
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Pharmacuticals (substances with medicinal properties)
Agrochemicals (pesticides, fertilizers, fungicides)
Dyestuffs (food dyes, clothing dyes, industrial dyes)
Food additives(preservatives, enhancers, the ‘E’s in food)
Perfumes
Vitamins
Pigments
Advantages of batch processes
• Good for small amounts of speciality
chemicals
• Make a range of products using same
equipment
• Can schedule maintenance & inspections
to equipment in between batches
• Good for developing new products
• Easier to scale up from lab scale
• Generally cheaper set up costs
• Employees understand the process well
Disadvantages of batch
processing
• Frequent start up and shutdown of
equipment – DOWNTIME!!
• Cleaning time between batches
• May be batch to batch variability
• Not good for bulk chemical
production
Examples of Continuous
Processes
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Sulphuric acid production
Sodium hydroxide production
Ammonia
Petrol
Chlorine
Methanol
Advantages of Continuous
Processing
• Good for large volumes (bulk
chemicals)
• Fewer start up and shutdowns –
UPTIME!!
• Potentially greater yields
• Potentially easier to maintain quality
or spot out of specification product
sooner
Disadvantages of
Continuous Processing
• Requires periodic shutdown of whole
plant for inspection and maintenance
• May rely on critical pieces of
equipment which have the potential
to stop production on whole plant
• Higher initial costs
• Employees knowledge of the
process is limited
Short Discussion : Synthetic Rubber Production
Designing in Safety
• Sets of legal and business standards to which
plants must comply
• Process Safety Management
• What if?
• Risk assessment
Key at the design stage is to review proposed
design, identify hazards and engineer them
out. If the hazard cannot be eliminated then
the risk must be reduced using various
means.
Examples of Safety Devices
– hierarchy of control
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Relief Valves
Rupture discs
Conservation vents
Failsafe logic
Process Interlocks
Alarms, monitoring of process conditions
Physical barriers
Personal Protective Equipment (PPE)
Training of personnel
Key Environmental
Considerations
• International/national laws
• Governmental conditions (licence to
operate)
• Again key is to eliminate or minimise
at design stage.
• If can’t eliminate then must look at
containment and treatment.
What will this Cost?
• Fixed Capital investment – Total
cost of the plant ready for start up.
• Working Capital investment –
additional investment required over
and above fixed capital to start the
plant up and operate it to a point
where income is generated.
Types of Costs
Fixed Capital Investment
Working Capital Investment
1.
Concrete and steel
1.
Start up
2.
Equipment
2.
Initial catalyst charges
3.
Piping
3.
Raw materials
4.
Instrumentation
4.
5.
Buildings for process and other
eg offices
Finished Product
Inventories
6.
Storage facilities
7.
Utilities provision
8.
9.
Non Capital Investment
1.
People involved in start
up
Design and engineering costs
2.
Travel
Contractors fees
3.
Training
How will we run the plant?
• Will it be 24/7 operation?
• How many people?
• What skills do they require
(operating technicians, maintenance
technicians, engineers)?
• What support staff (HR,
admin,finance, IT)?
An Oil Refinery
Photo courtesy Phillips Petroleum Company
http://science.howstuffworks.com/oil-refining.htm/printable
Fractional distillation of Crude Oil
Can be processed further to make other
products
Chlor-Alkali
HCl
Product
Hydrogen
Handling
HCl
Production
HCl
Storage
Chlorine
Compression
Chlorine
Liquefaction
Chlorine
Storage
Hypo
Production
Hypo
Storage
Hypo
Product
Caustic
Storage
Caustic
Product
Sulphuric Acid
Carbon Dioxide
NaOH
Chlorine
Drying
Salt
Demin. Water
To Hypo
Brine
Saturation
Primary
Treatment
Secondary
Treatment
Chlorine
Packing, Filling
Vaporization
Chlorine
Product
Sulphuric Acid
Sodium Sulphite
Sulphate
Removal
HCl
Electrolysis
NaOH
Brine
Dechlorination
Caustic
Concentration
Chlorate
Destruction
Demineralized Water
AC Power Supply
HCl
DC
Rectification
Hypo
Destruction
CHEMETICS
http://www.akerkvaerner.com/NR/rdonlyres/A078B10E-6369-48E5-9E2D-ECD2BFE2E628/12091/ProcessFigure1.PPT
Electrolysis
http://encarta.msn.com/media_461541587/Chloralkali_Electrolysis.html
Agrochemical Production
• Bulk chemicals production –how do
you think you would manufacture?
• Fertilisers – what hazards exist in
design and production?
Aim of Production
To make first time, first
quality product, safely, with
maximum yield
The Haber Process
N2(g) + 3H2(g) → 2NH3(g) ΔHo = -92.4 kJ/mol
•Reversible Reaction
• Exothermic reaction – best
yield obtained at lower
temperatures but rate of
reaction is too slow so
increased temperature is used.
• Catalyst is used to help speed
up the reaction rate
• Increased pressure increases
yield
What do you think are the key variables to control during production?
Recent Incident
Explosion at Terra Nitrogen (UK) Ltd, Billingham
01.06.2006
Terra Nitrogen is the UK's largest manufacturer of nitrogen products used
extensively in the chemical industry and agriculture and employs around
250 people on Teesside.
The incident happened on a pipe at the plant and led to a fire involving
mixed gases including hydrogen, nitrogen and a small amount of ammonia
which was extinguished automatically as the pipe depressurised. The exact
cause of the blast is not yet clear.
The HSE are currently investigating with the Environment Agency (EA).
Recent Incident
Buncefield Oil Storage Depot Explosion,
Hemel Hempstead – 11.12.2005
In the early hours of Sunday 11th December 2005, a number of explosions occurred at Buncefield Oil Storage
Depot. At least one of the initial explosions was of massive proportions and there was a large fire, which
engulfed a high proportion of the site. Over 40 people were injured; fortunately there were no fatalities.
Significant damage occurred to both commercial and residential properties in the vicinity and a large area
around the site was evacuated on emergency service advice. The fire burned for several days, destroying
most of the site and emitting large clouds of black smoke into the atmosphere. The Health and Safety
Executive (HSE) are leading a joint investigation with the Environment Agency (EA).
BBC News UK 09/05/2006
 A storage tank at the Buncefield oil depot was
overflowing for more than 40 minutes before it
exploded, causing a 32-hour inferno, a report has
said.
 Fuel was piped into the tank for 11 hours before the
blasts on 11 December 2005.
 The HSE said that at 0520 GMT the tank was full, but
gauges and safety devices did not work and 41
minutes later the tank exploded.
How Tank Overflowed: Under normal circumstances, gauges monitor the level of the fuel in the tank as
it fills from a pipeline. An automatic high level safety switch should trigger an alarm if the tank reaches
its maximum capacity. This should result in shutdown. But on this occasion, automatic shutdown did
not happen and when fuel continued to be pumped in, it overflowed through roof vents.
http://www.buncefieldinvestigation.gov.uk/index.htm
Key monitoring conditions
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Pressures
Temperatures
Flows
pH
Concentrations
Mixing rates
Running Costs
Fixed costs – Costs which are
paid regardless of production rate
Variable Costs – Costs
related to production
• Labour costs
• Raw materials
• Maintenance costs
• Utilities
• Admin costs (insurances, rates,
taxes)
• Packaging
• Storage and distribution
Questions?
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