Evaluation of Increased Recycling as an Alternative
to Energy from Waste Disposal – West Hartford CT.
Bernard Pelletier
MANE 6960 – Solid and Hazardous Waste Prevention and Control Engineering
Professor Gutierrez-Miravete
RPI - Hartford
Spring 2014
Abstract
The Town of West Hartford Connecticut is a prosperous and forward-looking town in
central Connecticut.
Starting in 2014 the town has undertaken an initiative to increase the diversion of
residential solid waste to recycling from its current level of 33%.
This paper will examine this initiative from several perspectives:
 The economic implications to the town
 The effort and tactics employed to achieve the goal
 The guidance/ regulatory background provided by Connecticut’s Department of
Energy and Environmental Protection
 The engineering evaluation of the choice between recycling and trash to energy
The paper will also discuss key assumptions of the engineering evaluation and make
suggestions for improved performance (regardless of what mode of disposal is
employed).
1
Background – Town of West Hartford Solid Waste Treatment
Collection
The Town West Hartford (WH) has a comprehensive system for handling its solid waste.
While this discussion is confined to the handling of Residential Solid Waste WH’s
approach to refuse is comprehensive and includes Commercial waste as well as
Residential Waste.
The key features of WH’s Residential waste management are1:
 Residential trash (green barrel) is collected weekly by Paine’s Incorporated.
 Residential recycling (blue barrel) is collected every two weeks by Paine’s
Incorporated.
 Large “bulky waste” and large metal items are collected for a separate fee by
Paine’s Inc. They are recycled by Paine’s LLC.
 Yard waste may not be put in a green barrel – WH encourages residents to drive
the yard waste to the transfer station – in order to do that the town requires an
annual permit to be purchased. The yard waste can be recycled for $27 per ton–
vs. $61.20 per ton if put in the green barrel. WH estimates that because residents
DO put yard waste in the green bins it costs WH $100,000 extra in tipping fees.
 In the spring and the fall there is yard waste pickup by the town (free). Leaves
must be bagged.
 There are two Hazardous waste pickup events per year.
 Electronic waste is handled by “Greenmonster” who will take “anything with a
plug”.
Outside of this framework there are several additional collection pathways for residential
waste:
 Certain bottles and cans are returnable to supermarkets and liquor stores (e.g.
aluminum cans and bottle containing carbonated beverages). A credit is given for
the return of these items (which covers the additional amount added to the price at
the time of sale).
 Plastic bags may be recycled at supermarkets.
 Other – animal remains, hardcover books, and other sorts of specific waste may
have their own pathways to disposal.
Disposal
At the end of each of these collection modalities the material is either recycled or burned
in a waste to energy plant (WTE). The waste to energy plant is run by Covanta and is
situated in Bristol Connecticut. Ashes are placed in a landfill.
1
http://www.westhartford.org/living_here/town_departments/public_works/refuse_and_recycling/c
urbside_collection/index.php
2
The recycling of yard waste is run by EnviroCycle LLC. Material is composted at the
transfer station on Brixton Road, West Hartford. The results of the composting process
are available to residents for a fee.
Recycling of material from the “blue bins” is handled by ReCommunity Recycling using
a Materials Recovery Facility located on Brainard Road.
Recycling Program and Town Economics
WH has begun a campaign to increase the amount recycled into the blue bin.
Starting in 2014 the town has committed to increasing the amount recycled from
Residential and Municipal wastes streams2. Currently according to Mr. David Gabriele,
the town’s environmental service manager, WH recycles 33% of its solid waste
amounting to approximately 8000 tons of recycled material per year. The short-term goal
is to increase that to 9000 tons next year (2015). While this amounts to a 12.5% increase
the new recycling rate would only be 37% if it is assumed that the over all amount of
trash remains constant. This is below the federal goal of 50% (by 2015) and far below the
Connecticut goal of 58% (however that is the goal in 2024 – 10 years hence).
There is an economic incentive to increase the amount recycled because for each ton
recycled in the blue bin WH receives on average $12.00. Annually then WH’s 8000 tons
of recycling produces $96,000 in income. It also avoids a tipping fee of $57 per ton
amounting to $456,000 annually. Currently the town pays $91,000 per month
($1,092,000 annually) to Paine’s LLC for a recycling pick up every other week. If WH
met its recycling goals of 9000 tons in 2014 it would avoid $513,000 in tipping fees- an
increase of $57,000.
Even if WH meets its 2015 goal of 9000 tons the per ton payment and the avoid tipping
fee covers only about one half of the annual cost of pickup.
Tactics to Increase Recycling
The initial tactic that WH is using is to increase the recycling knowledge of WH
residents:
“Gabriele and Phillips believe that the first step toward increasing recycling is
providing residents with clear information about what can and can’t be recycled,
as well as other pertinent information. The new recycling campaign will do just
that. The cost of outreach and education is being paid through a grant that the
town received from its waste disposal contractor, Covanta Energy Corporation.”3
Thus far WH has revamped the recycling web page and started an online “trash court”
where residents can get answers to whether something should be recycled or trashed.
2
http://westhartford.patch.com/groups/west-hartford-recycles/p/west-hartford-launches-new-recyclingcampaign
3
http://westhartford.patch.com/groups/west-hartford-recycles/p/west-hartford-launches-new-recyclingcampaign
3
They have also hired a publicist who has written articles on this topic for the local media.
Because the benefits of recycling are so tied to energy the Clean Energy Task Force
(CETF) and the department of public works are starting a collaboration process to share
ideas and resources. The first meeting is scheduled for April 11, 2014.
State Regulation and Guidance
As noted above WH does not meet either the State or Federal goals for recycling (nor do
most towns in Connecticut). These goals are advisory – and indeed while there is a
wealth of material on the topic of recycling the State and Federal EPA are not
prescriptive as to percentage recycled. In addition their guidance varies somewhat.
However there is basic agreement on the rank order desirability of options. Both the
DEEP (Connecticut’s Department of Energy and Environmental Protection) and the EPA
promote the following hierarchy for handling solid waste:
In Connecticut Recycling is mandated by law (not the percentage however). Since
January 1999 Connecticut has mandated that certain items are to be recycled.
Additionally there is a list of items that cannot be disposed of in the trash.
The items that must be recycled are:
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Items Designated (i.e. Mandated) for Recycling
Glass & Metal Food & Beverage Containers
Plastic Containers (PET or PETE #1)
Plastic Containers (HDPE #2)
Corrugated Cardboard
Boxboard
Newspaper
Magazines
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White & Colored Office Paper (residences and businesses)
Scrap Metal, including appliances
Ni-Cd Rechargeable Batteries (from consumer products)
Waste Oil (crankcase oil from internal combustion engines)
Leaves (must be composted)
Lead Acid Battery or Motor Vehicle Batteries
Grass Clippings (should be left on the lawn or, if necessary, composted )
Commercially Generated Source Separated Organic Materials
In addition to mandating that certain items be recycled the Connecticut Law bans
material such as grass clippings, electronic devices, and lead acid batteries from being
disposed of in the trash.
It is safe to say that the majority of residents don’t view recycling as a being required by
law – and that many also improperly dispose of material in violation of the law. There is
a great opportunity to increase knowledge and compliance.
The excerpt below 4details the key reasons that Connecticut for established a solid waste
recycling goal of 58% by 2024:
“The following are among the key issues that will shape solid waste management in coming years:
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If Connecticut doesn’t substantially increase the rate of MSW disposal diversion; it is projected to
have an increasing shortfall of MSW in-state disposal capacity.
Currently there is increasing out-of-state capacity for solid waste disposal at competitive prices.
Solid waste is a commodity subject to interstate commerce laws.
(Some bullets omitted)
Nationally, recycling of non-traditional material streams has grown significantly
National and global recycling markets have grown substantially
Other states and communities have demonstrated an ability to achieve higher waste diversion rates
than Connecticut has achieved to date.
There is a growing interest in product stewardship and producer responsibility policies.”
The motives displayed in the excerpt above run the gamut from – because we are running
out of room - to because we can - to because everyone else is - to (finally) – because it is
the right thing to do.
As noted above the push to recycle had several motivations. Reducing the use of landfills
was one of them – and Connecticut has been very successful in this endeavor:
“The shift to waste-to-energy technology was highly successful in minimizing the amount of solid
waste sent to landfills. There is now only one landfill in the state that receives municipal solid
waste (MSW). That landfill, in Windsor, Connecticut, takes in less than 10,000 tons of MSW per
year. In 2010, the Department of Energy and Environmental Protection (DEEP) reported that 92
percent of MSW was not disposed of in landfills. Of this amount, approximately one-third is
recovered through recycling and two-thirds is combusted for energy. The combusted portion of
Connecticut’s trash is converted to more than one million megawatt hours of electricity, enough to
4
State of Connecticut – State Solid Waste Management Plan – Amended December 2006,
http://www.ct.gov/deep/lib/deep/waste_management_and_disposal/solid_waste_management_plan/swmp_f
inal_chapters_and_execsummary.pdf
5
power more than 100,000 homes.”5
Solid Waste Engineering - Recycling vs. Waste to Energy (WTE)
The Waste Management Hierarchy, supported by DEEP and the EPA, promotes recycling
as superior to Waste to Energy. WH’s campaign to increase recycling is in line with this
rank order.
We now turn to discussing how this determination is made, key assumptions in that
determination, and whether it applies universally. This analysis relies on two papers both
of which directly address the question of whether it is desirable to recycle or to engage in
Waste to Energy (WTE).
Richard Denison’s paper entitled “Environmental Life Cycle Comparisons of Recycling,
Landfilling, and Incineration – A review of Recent Studies”6, compiles four studies that
all seek to establish the relative merits of these three modes of solid waste disposal. The
four studies that Denison reviewed were conducted by:
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Franklin Associates –
The Tellus Institute
The US Department of Energy – (conducted at the Stanford Research
Institute)
Sound Resource Management Group
The conclusion of the paper is that:
“all of the studies support the following conclusions: Systems based on recycled production plus
recycling offer substantial system-wide or “life-cycle” environmental advantages over systems
based on virgin production plus either incineration or landfilling, across all four parameters
examined. Only when the material recovery or waste management activities are analyzed in
isolation—which does not account for the system-wide consequences of choosing one system
option over another—do the virgin material–based systems appear to offer advantages over
recycled production plus recycling.”7
All four studies examine the overall Life Cycle of MSW as it is treated in Landfilling,
Incineration, or Recycling by quantifying the immediate outputs and energy demands of
each process. The studies then examine the system wide consequences of each mode of
5 Resource Recovery Task Force Final Report, Dec 13, 2013,
http://www.ct.gov/deep/lib/deep/waste_management_and_disposal/solid_waste/transforming_matls_mgmt/
resources_recovery_task_force/rrtf_final_report.pdf
6 Environmental Life Cycle Comparisons of Recycling, Landfilling, and Incineration – A review of Recent
Studies, Richard A Denison, Annual Review of Energy and the Environment, 1996, Volume 21, pages 191236.
7 IBID page 1
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disposal. The four studies study similar waste streams (3 include only municipal waste
while one includes Institutional and Commercial waste in addition to municipal waste).
The studies compare the system wide impact of landfilling all material from a waste
stream and thus having to acquire virgin materials and manufacture goods from those
virgin materials to waste incineration (which produces energy) but still requires the
acquisition and manufacture of virgin materials to recycling – where the major system
savings lies in not needing as much virgin material and incurring lower manufacturing
costs (note that manufacturing and energy consumption each create ADDITIONAL solid
was from the manufacturing process).
The key assumption in the recycling analysis is that the recycled material prevents the
need for virgin material and associated processing and manufacturing cost. The study
does not state this as an assumption and is therefore biased in favor of recycling.
The author compares the three disposal modes using 4 metrics (only the Franklin study
produced all 4 metrics):
1.
2.
3.
4.
Solid Waste produced
Energy consumption of the process
Air emissions
Water emissions (to shorten the discussion this paper only reports on the air
emissions – but the conclusion of the author is very much the same for Air and
Water emissions.
The immediate impacts are easy to determine and would include:
• Energy cost of collection of MSW – the same for all three disposal methods
• Energy and solid waste associated with transport to landfill, incinerator, or
recycling center
• Energy and solid waste consequence of recycling.
• Transport of ashes from incinerator to landfill.
• Transport of recycled materials to re-manufacturing center.
•
The system wide factors would include acquiring virgin material by mining, logging, oil
extraction, natural gas extraction, etc. The energy, pollution, and solid waste aspects of
these processes ARE factored into the cost equation. So by way of example if natural gas
were required as a feedstock to make a plastic the energy to drill, the waste from the
drilling, and the pollution from that process would be considered. Once the material is
acquired the energy, waste, and pollution consequences of the subsequent processing
would also be considered. So for example in the case of aluminum – the processing of the
Bauxite ore into a material suitable for a manufacturing process would be factored in.
Solid Waste Engineering - Recycling vs. Trash to Energy – Amount of Waste
Produced
This discussion references the diagram graph below taken from Denison. The graph
compares the solid waste metric handling one ton of MSW under each disposal option.
7
The landfilling result is straightforward – it is one ton of material with a slight add on
representing the solid waste implication of the energy needed to get the material to the
landfill.
The incineration option generates 534 pounds per ton of original waste. In this analysis
however there is an additional “credit” that represents the fact that the energy produced in
a WTE plant eliminates the need for a certain amount of other fuel – which reduces the
amount of overall system wide solid waste. This credit reduces the 534 to 446. Clearly
the 2000 lbs. to 534 drop is a function of substituting ash for unburned waste.
It is apparent that the weight of the flue gases is NOT included in this amount.
The recycling option likewise has two credits – the first for the amount pulled out of the
landfill (leaving behind residue of only 184 lbs. per ton) and the second – a very large
credit for the net avoidance of solid waste from acquisition, transport, processing, and
manufacturing. The second credit is large enough to drive the evaluation of the solid
waste negative. That is to say recycling X will result in saving more than X in solid
wastes! In the graph below the top portion (a) represents the comparison with all in
system and
out17,of1996system
The lower portion
September
17:25 implications.
Annual Reviews
DENIBACK(D).DUN
AR16-08 of the graph (b) represents the
amount of landfill impact just with in the system.
FRANKLIN STUDY SOLID WASTE OUTPUT – PER TON OF MATERIAL
ENVIRONMENTAL LIFE–CYCLE COMPARISONS
209
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Solid Waste Engineering - Recycling vs. Trash to Energy – Amount of Energy Saved
The next chart (below) compiles the results of an overall assessment of energy use for the
three options. While the studies vary considerably in their per ton assessment the “NET”
estimated energy consumption is in the same relative order – with Landfilling not
requiring much energy – but generating very little offset (methane production).
Incineration generates a large energy credit but in all three studies the credit ascribed to
avoiding virgin material production and manufacturing dwarfs the trash to energy
September 17, 1996
17:25
Annual Reviews
DENIBACK(D).DUN
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contribution.
ENERGY USE PER TON MANAGED –FRANKLIN – TELLUS -DOE8
ENVIRONMENTAL LIFE–CYCLE COMPARISONS
219
Comparing the three studies above it is clear that the Franklin study provides the most
favorable assessment of Recycling vs. Incineration. Jeffrey Morris in a 1996 paper9
conducts a separate comparison of WTE vs. Recycling and his results support the
pg. 219 Denison
Jeffrey Morris, Recycling versus incineration: an energy conservation analysis, Journal of Hazardous
Materials, Vol 47, (1996), pages, 277-293
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9
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Franklin relativity. Reading the Net graph above Franklin suggest that WTE produces
about 5Million BTUs per ton managed vs. a Net contribution of about 16 Million BTUs
for Recycling. This implies that WTE yields about 31% of the energy that Recycling
saves system wide. In Morris’s analysis he estimates that across 25 typical components of
MSW a WTE plant would produce 6132 Kilo Joules per kilogram of material. A
conservative estimate of recycling energy saved is 20,060 KJ/Kg. This yields the same
31% relativity as the Franklin study10.
Morris provides insight into the reasons for the size of the differential:
1. The use of MSW as a fuel is less efficient that using a traditional fossil fuel. By
his estimate the varying seasonal impact, moisture issues, and variability of MSW
as a fuel results in only 15% of the “textbook” heat value of the MSW being
converted to electricity in contrast to an approximate 33% conversion of coal or
oil. This paper was written in 1996 so it is possible that the efficiency of burning
MSW has increased – but it is also likely that the efficiency of the conventional
plants has increased also (especially in light of Electricity being generated from
Natural Gas). I intend to ask the engineers of the Covanta plant in Bristol what
their efficiency is.
2. Morris makes it explicitly clear that the Recycling energy credit is dependent on
what virgin materials recycling saves and what manufacturing from virgin
materials is avoided. His table 1 provides estimates for 25 typical components and
gives a high and low estimate of energy avoided. The 20060 KJ/Kg statistic above
is the LOW estimate.
Solid Waste Engineering - Recycling vs. Trash to Energy – AIR Pollution Avoided
1996now
17:25
Annualpattern
Reviews for
DENIBACK(D).DUN
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The chart below September
shows17,the
familiar
the different air
pollutants arising out
of the three processes. The larges effect is from the avoided manufacturing cost.
AIR POLLUTION PER TON MANAGED –FRANKLIN – TELLUS -DOE11
ENVIRONMENTAL LIFE–CYCLE COMPARISONS
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11
Morris,Table 1 pages 284,285.
pg. 219 Denison
229
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Conclusions
Based on the two studies, which compare the Lifecycle impact of recycling vs. WTE, it
would appear that the DEEP and EPA guidance is correct and the town is wise to proceed
with the proposed campaign to increase recycling.
However the studies cited in this paper are nearly 20 years old and it is to be expected
that technologies in the both the recycling and WTE have improved. It is unlikely that the
general direction towards recycling would be overturned –but it is entirely possible that it
may be different for a particular waste product – e.g. number 7 plastic. One key to
making that determination is the end use of the recycled product. If it does not prevent
virgin material usage it needs reexamination.
In order to facilitate keeping the desirability relationship between recycling and WTE it
would be useful to keep track of at least some of the components of the various
processes. Some examples:
 KwH per ton of MSW
 KwH used by the Materials Recycling Facility (MRF)
 Where various materials are recycled – and into what products. For example if
plastic is simply recycled into low end “plastic wood” it may not be worth
expending the effort to recycle.
 As WH residents become more informed about their trash special focus may be
brought to bear on specific types of waste. So statistics on the components of
MSW would be valuable as we seek to minimize green barrel waste. We discuss
food and yard waste below – but other types of trash might benefit from special
handling as well (e.g. diapers)
In the initial stage of the campaign – WH is focusing on educating residents to get more
material out of the green bin and into the blue bin (legitimately). However a clear
additional step involves getting food waste and yard waste out of any bin and into a
composting process – whether at home or at the transfer station. As noted earlier in the
paper David Gabriele is quoted as saying that WH incurs 100,000 of extra tipping fees
due to yard waste being improperly disposed of. Using a $57 tipping fee and dividing into
the 100,000 figure suggest that 1,754 tons of yard waste is improperly disposed of. This
ought to be addressed for two reasons:
1. The high moisture content of the material lowers the heat value of the overall
WTE fuel stream and
2. The material could be composted and used for mulch resulting in savings to WH,
less CO2 and little drop in the WTE electrical output.
Two thoughts on how to do this:
1. Eliminate the annual tag needed to bring branches and clippings to the transfer
station and
2. Have 3 seasons pick up - (i.e. add the summer).
11
In discussions with Mr. Gabriele the main purpose of the annual tag is to prevent misuse
of the recycling facility. If this could be addressed in another way (ID check for example)
it might increase the amount of yard waste recycled outside the green bin. Also the
suggestion for 3 seasons pick up requires additional work and competes for resources
now devoted to road repair and maintenance. The solution is not simple – but it is
definitely worth more thought.
While the education effort is now a Town effort there are great synergies possible if the
state or a regional approach were taken. The state could provide on air and on line
education to the entire state. Likewise regions of towns that use the same Materials
Recycling Facility could band together and do the same.
Finally – while WH informs residents on how to recycle there are also steps that it can
take to reduce and reuse materials. Mr. Gabriele indicates that junk mail constitutes much
of the paper waste – and this may be addressed by education. Another logical step would
be to incent merchants and customers to use less packaging when shopping. In addition
using less packaging – encouraging the use of recyclable packaging would also be
beneficial. Mr. Gabriele cites the three types of egg cartons as an example:
 Cardboard cartons are recyclable
 Clear plastic cartons are recyclable
 Styrofoam cartons are NOT recyclable.
It may be possible to encourage manufactures to adopt packaging materials that both
merchants and residents can recycle.
This effort represents the intersection of engineering, community outreach, and
sustainable development. While trash may seem like a humble topic – the downstream
environmental benefits of this initiative are anything but humble!