FY2004 OSWER Innovation Pilot Results Fact Sheet
oEPA
Using Auto Shredder Residue as
Cement Manufacturing Component
The Environmental Protection Agency's Office of Solid Waste and
Emergency Response initiated a series of innovative pilot projects to test
ideas and strategies for improved environmental and public health results.
This series of fact sheets highlights the innovative approaches, results, and
environmental and economic benefits from the pilot projects that may be
replicated across various sectors, industries, communities, and regions.
PROJECT DESCRIPTION/INNOVATION
EPA awarded a grant to the California Office of Pollution
Prevention and Technology Development to study the
feasibility of using automobile shredder residue (ASR) as a
supplemental fuel and mineral feedstock (the raw material
required for production) in cement kilns, to both fuel the kilns
and manufacture cement, The main barrier to the recovery of
energy value from ASR had been the perception that it was too
contaminated, had a low heating value, and the variability of its
physical nature, However, cost-effective methods to separate
ASR into energy and mineral rich materials facilitated its use
for both fuel and cement production. This project identified
the feedstock quality parameters and the mechanical means
necessary to process ASR into material suitable for both fuel
and cement production, This project represented the first ASR
tests for these uses in the United States,
BACKGROUND
Auto shredder residue (ASR) is comprised of materials
remaining after a vehicle has been shredded and removed of
reusable parts and metals. These materials include plastics,
rubber, foam, residual metal pieces, paper, fabric, glass, sand
and dirt. According to a 2004 study, more than three million
tons of ASR were generated in the U.S. annually, and nearly all
was landfilled.
ASR could potentially be used as a supplement to
conventional fuel in cement kilns. Studies show that cement
kilns use a wide variety of different fuels without compromising
cement product quality, plant operations or emissions.
Numerous studies have illustrated the successful use of
alternative fuels and minerals in cement manufacturing, the
resulting benefits of energy and raw materials savings, the
incorporation of residual ash into the cement product, and the
destruction of organic constituents in the fuel.
However, unprocessed ASR has poor fuel characteristics, due
to its high ash content; the presence of contaminants, including
heavy metals, chlorine, and polychlorinated biphenyls (PCBs);
	About one million tons of ASR could be recovered for
fuel in the U.S., which would comprise approximately
six percent of the U.S. cement manufacturing
industry's energy consumption and save $50 million
annually (assuming $50 per ton of coal).
	One million tons of avoided landfilling would amount to
more than $20 million savings annually.
	Use of one million tons of ASR for fuel would result
in reduced C02 emissions and the conservation of
approximately one million tons of coal annually,
and its composition of approximately 20 to 50 percent
incombustibles. Prior to use as a fuel, ASR required separation
and processing to isolate combustible materials with low ash
content and low contaminant concentrations. Since many reuse
and recycling options may not be environmentally beneficial or
cost effective, there was a need for further study.
PROJECT SUMMARY
In 2004, the California Department of Toxic Substances Control
(DTSC), in cooperation with the University of California at
Berkeley and EPA's Office of Resource Conservation and
Recovery (ORCR), conducted a study to identify the feedstock
quality parameters needed to satisfy kiln operators and
assess the mechanical means necessary to process ASR
into material acceptable as coal and mineral feedstocks for
cement production. To test this concept, this study investigated
cost-effective methods for separating and processing the ASR
stream to make it a suitable fuel for cement kilns.
DTSC conducted laboratory tests to assess the ASR
characteristics, including physical parameters and fuel
characteristics, as well as beneficial elements and contaminant
concentrations of PCBs and other contaminants, Based on
the results, DTSC worked with kiln operators to determine

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the considerations for supplemental fuel and mineral
additives. DTSC then conducted field tests to demonstrate
separation techniques to recover valued streams. Physical and
chemical laboratory tests determined the energy, mineral and
contaminant content of the processed streams and validated
conformance with kiln specifications. DTSC estimated operating
costs for a full scale separation system and compared it to the
costs of landfilling ASR. In addition, EPA worked with DTSC to
ensure any environmental issues were addressed including the
collection of data on mercury, cadmium, lead and PCBs.
RESULTS
The physical and chemical test results allowed kiln operators
to assess the limitations of ASR as a fuel or mineral substitute.
The study showed beneficial mineral content (namely silicon)
was less than expected. After discussions with shredder
operators, it was determined that substantial removal of glass
occurred at the dismantling yards before automobiles reached
the shredding facility. As a result, recovery of ASR for mineral
content was not studied further.
The demonstrated separation method achieved a mixture of
ASR that represented 30 percent of the original mixture and
had a heating value of approximately 13,240 Btu per pound,
which was higher than that of most coal types. Applying the
results of this study to the U.S. would result in about one million
tons of ASR recoverable for fuel. Using this amount for cement
kilns could save the cement manufacturing industry $50 million
annually through reduced energy cost (assuming $50 per
ton of coal). It could also save auto shredding operations $20
million annually in avoided landfilling costs. While the costs of
processing the ASR for use in cement kilns would also amount
to $20 million annually, auto shredding operations could also
generate $20 million annually in revenue from the sale of
copper (based on 13,000 tons of copper alone).
If the estimated one million tons of recovered ASR was used
instead of coal in U.S. cement kilns, it would potentially provide
six percent of the cement industry's energy needs. It would
also result in reduced C02 emissions and the conservation of
approximately one million tons of coal annually. Additionally,
potential impacts of landfill leachate contaminated with ASR
constituents would be avoided by diverting ASR from landfills.
The study further found that additional financial and
environmental benefits could be realized by providing incentives
for ASR recovery, and by supporting markets for ASR derived
products.
Lead: California Office of Pollution Prevention and
Technology Development
Sponsor: U.S. EPA Office of Resource Conservation and
Recovery
Other Partners:
	Hugo Neu-Proler Co.
	Mitsubishi Cement Company
	University of California at Berkeley
OSWER Innovation Projects:
www.epa.gov/oswer/iwg/pilots/
EPA's Recycling Automotive Parts:
www.epa.gov/osw/conserve/materials/auto.htm
2010 UPDATE
DTSC and EPA continue to research the benefits of using
ASR as a supplemental fuel and mineral feedstock in cement
kilns. In 2006, DTSC authored and EPA co-funded the report,
Evaluation of Shredder Residue as Cement Manufacturing
Feedstock, and in 2008 EPA developed the draft report, Cement
Sector Trends in Beneficial Use of Alternative Fuels and Raw
Materials. In March 2010, these research efforts were used in
support of EPA's Resource Conservation and Recovery Act
(RCRA) proposed rulemaking: Identification of Nonhazardous
Secondary Materials That Are Solid Waste.
A	United States
Environmental Protection
m m Agency
OSWER Innovation Pilot Results Fact Sheet
Using Auto Shredder Residue as
Cement Manufacturing Component
 August 2010

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