HomeMy WebLinkAboutAgenda - 09-02-2008 - 7aORANGE COUNTY
BOARD OF COMMISSIONERS
ACTION AGENDA ITEM ABSTRACT
Meeting Date: September 2, 2008
Action Agenda
Item No. "7-q
SUBJECT: Solid Waste Process Technology Assessment
DEPARTMENT: PUBLIC HEARING: (YIN) No
ATTACHMENT(S): INFORMATION CONTACT:
Final Report - Solid Waste Process Gayle Wilson, 968 -2885
Technology Assessment (Under
Separate Cover)
PURPOSE: To provide an assessment of solid waste processing technologies (WPT) as
alternatives to landfilling as a primary means of waste disposal.
BACKGROUND: The Board of County Commissioners requested that an assessment of
alternative solid waste processing technologies be conducted and referred this request to the
Solid Waste Advisory Board (SWAB). At its February 7, 2008 meeting, the SWAB discussed
methods and rationale for evaluating alternative technologies. At the April 3, 2008 SWAB
meeting, an outline for a scope of work was adopted and utilized to develop a final scope of
work for Olver, Inc. In late April, staff authorized Olver, Inc. and their sub - consultant GBB, Inc.
to proceed with the Waste Processing Technology Alternative Study. At the June 24 BOCC
meeting, a status report was provided that indicated that a final report would be presented at
the September 2, 2008 BOCC meeting. GBB, Inc. conducted a presentation of the draft final
report to the SWAB at its August 7, 2008 meeting.
The consultant in the report concludes:
• the quantity of Orange County post diversion solid waste available for WPT is much less
than would support or justify any of the alternative technologies available or considered
in the report,
• even with about 35% more waste available to process, the cost, at least $100 per ton,
would be significantly greater and include more variability risk when compared to the
approximately current $50 per ton for landfilling,
• economies -of -scale apply to WPT to a degree as much as, or greater than transferring
and landfilling,
• residue /ash and by -pass material, which consists of as much as 30 -35% by weight of the
incinerated material, would still require disposal by landfilling or, if feasible, an alternative
use, which has not been widely accepted in the United States,
• partnering with adjacent governments may provide the necessary quantity of waste
available to make a WPT project financially viable,
• many of the WTP discussed in the report are, at this time, considered unproven, have
limited operating experience, have only operated at a experimental scale or are presently
under development, have already been proven unreliable /infeasible, or still have very
high technological risk factors,
• mass burn waste to energy and pre - processing for a refuse derived fuel are the most
proven, environmentally secure, and technologically reliable WPT,
• County sponsorship and public ownership would be required to insure capital, waste flow
control, and financing,
• all WPT are compatible with a high level of recycling, and
• siting a WPT will likely be as politically difficult as siting a landfill, although less space
would be required for the WPT.
The Solid Waste Advisory Board and staff advises:
While some WPT options may appear to have a degree of technical and environmental
feasibility, there is little short-term potential for waste processing technologies for Orange
County. There is insufficient waste available to support such a facility and the inherent
technological and financial risks are deemed exorbitant. Current energies and attention should
remain focused on completion of the transfer station development process and the
comprehensive, long -term, planning process underway by the Solid Waste Management Work
Group. Recommendations likely to surface through the Work Group's deliberations, if ultimately
adopted by the BOCC, will themselves require considerable time (3 -5 years), energy and
resources to effectively implement.
Work Group recommendations are anticipated to be presented to the elected bodies by the
spring of 2009. Consequently, the SWAB and Solid Waste management advise no further
action at this time on alternate waste processing technologies.
FINANCIAL IMPACT: There is no financial impact associated with receiving the Solid Waste
Process Technology Assessment. There would be considerable cost associated with the
adoption for implementation.
RECOMMENDATION(S): The Manager recommends that the Board receive the attached
report, request additional clarification from the consultant as necessary, and authorize no
further action pending completion of the Solid Waste Management Work Group
Recommendations.
Alternative Waste Processing Technologies
Assessment
(A White Paper)
Prepared by:
an
Gershman, Brickner & Bratton, Inc.
8550 Arlington Blvd, Suite 203
Fairfax, VA 22031
1 -800- 573 -5801
August 15, 2008
Table of Contents
EXECUTIVESUMMARY ................................................ ............................... ES -1
1.0 INTRODUCTION AND BACKGROUND ........................ ............................... 1
2.0 FUTURE ORANGE COUNTY WASTE DISPOSAL NEEDS .. ............................... 3
3.0 WORLDWIDE EXPERIENCE OF WASTE PROCESSING TECHNOLOGIES
ANDVENDORS ..................................................... ............................... 5
3.1 Mass- Bu rn/Waterwa I I Combustion .................. ............................... 5
3.2 Mass - Burn /Modular Combustion .................... ............................... 5
3.3 Refuse - derived Fuel /Dedicated Boiler ............. ............................... 6
3.4 RDF /Fluidized Bed ....................................... ............................... 6
3.5 Gasification ................................................ ............................... 6
3.6 Pyrolysis .................................................... ............................... 6
3.7 Plasma Arc ................................................. ............................... 7
3.8 Biological Fuel Production ............................. ............................... 7
3.8.1 Cellulosic Ethanol .............................. ............................... 7
3.8.2 Biogas - Anaerobic Digestion ............... ............................... 8
4.0 RECENT RESEARCH /PROCUREMENTS FOR WASTE PROCESSING
TECHNOLOGIES BY OTHERS ................................. ............................... 12
4.1 Recent Research ....................................... ...............................
13
4.1.1 New York City, NY .............................. .............................13
4.1.2 City of Los Angeles, CA ....................... .............................14
4.1.3 Los Angeles County, CA ....................... .............................15
4.1.4 King County, WA ................................ .............................17
4.2 Procurements ........................................... ...............................
17
4.2.1 Frederick and Carroll Counties, MD ........ .............................17
4.2.2 Harford County, MD ............................ .............................18
4.2.3 City of Sacramento, CA ....................... .............................19
4.2.4 Broward County, FL ............................ .............................19
4.2.5 St. Lucie County, FL ............................ .............................20
4.2.6 Hawaii County, HI ............................... .............................20
4.2.7 Pinellas County, FL ............................. .............................20
4.2.8 Hillsborough and Lee Counties, FL ......... .............................20
4.2.9 Fairbanks North Star Borough, AK ......... .............................21
4.2.10 City of Tallahassee, FL ......................... .............................21
4.3 Comparison of Technologies Chosen in Recent
Research/Procurements .............................. ...............................
22
5.0 OPINION ON ECONOMIC FEASIBILITY, EFFECTIVENESS, AND
ENVIRONMENTAL ISSUES OF WASTE PROCESSING TECHNOLOGIES..........
23
5.1 Economic Feasibility of Waste Processing Technologies ..................
23
5.1.1 Typical Waste Processing Technologies Project Economic
Estimates.......................................... .............................23
5.1.2 Assumptions ...................................... .............................24
5.1.3 Pro Forma Operating Statement ........... .............................25
GBB/C07063 -01 ii August 15, 2008
5.2 Effectiveness of Waste Processing Technologies ............................ 25
5.3 Environmental Issues of Waste Processing Technologies ................ 26
5.3.1 Air Quality ......................................... .............................26
5.3.2 Water ............................................... .............................29
6.0 OPINION ON WHICH WASTE PROCESSING TECHNOLOGIES SHOULD
BE CONSIDERED FOR ORANGE COUNTY ................. ............................... 30
List of Tables
Table 3 -1. U.S. Mass- Burn/Waterwal I Facilities ................... ............................... 5
Table 3 -2. Commercial Cellulosic Ethanol Plants in the U. S ... ............................... 8
Table 3 -3. Biogas Production in Europe .............................. .............................10
Table 3 -4. Biogas Firms in Europe ..................................... .............................10
Table 4 -1. Technologies/Vendors Mentioned in Recent Procurements ................... 22
Table 5 -1. Pro Forma Annual Operating Statement ............... .............................25
Table B -1. WTE Facilities Worldwide ............................... ............................... B -2
List of Figures
Figure 1 -1 - Solid Waste Management Hierarchy ................. ............................... 1
Figure 5 -1.
Dioxin Emissions from WTE Facilities, 1990 - 2005 ...........................
28
Figure 5 -2.
Mercury Emission from WTE Facilities, 1990 - 2005 ..........................28
Figure B -1.
Waterwall Furnace Section ........................... ...............................
B -4
Figure B -2.
Typical Mass -Burn Waterwall System ............. ...............................
B -5
Figure B -3.
Typical Modular Combustion System .............. ...............................
B -6
Figure B -4.
Typical RDF Combustion Facility .................... ...............................
B -7
Figure B -5.
Typical RDF Processing Schematic ................. ...............................
B -8
Figure B -6.
Typical RDF Fluid Bed System ....................... ...............................
B -9
Figure B -7.
Typical Gasification System ........................ ...............................
B -10
Figure B -8.
RDF Fluidized Bed Gasification System ......... ...............................
B -11
Figure B -9.
EnTech Process Schematic ......................... ...............................
B -12
Figure B -10.
Process Diagram of a Pyrolysis System ...... ...............................
B -13
Figure B -11.
Cross - Section of a Plasma Arc Furnace ....... ...............................
B -14
Figure B -12.
Process Flow of the BCyL Biomass Ethanol Plant ..........................
B -16
Figure B -13.
Process Flow for Anaerobic Digestion System 17 ...........................
B -20
Figure B -14.
ArrowBio Facility in Haifa .......................... ...............................
B -21
Appendices
A -1 Firms Evaluated by Recent Waste Processing
Studies or Procurements ..................................... ............................... A -1
A -2 Summary of Municipal Waste Processing Technologies ............................ A -2
B Overview of Waste Processing Technologies .......... ............................... B -1
GBB/C07063 -01 iii August 15, 2008
Executive Summary
This examination of alternative waste processing technologies (WPT) was undertaken
at the behest of the Orange County Board of Commissioners to explore and evaluate
alternatives to landfill disposal of the County's municipal solid waste. The purpose of
this white paper is to initiate that evaluation and brief the County's solid waste staff,
elected officials, Solid Waste Advisory Board, and citizens on state -of- the -art solid
waste processing technologies, emerging technologies and their applicability to the
County's needs, and the potential of these technologies to contribute to the County's
overall solid waste management system.
Orange County generated approximately 116,000 tons of waste in FY2006 -07, or
about 318 tons per day (TPD). Of that material, 62,900 tons or 172 TPD were
disposed of in landfills, and 29,700 tons or 24 percent was recycled. The County is
examining ways to achieve its goal of 61 percent waste reduction, up from their
current rate of 48 percent. The County's landfill is projected to close in 2011. The
County has decided to manage its future waste using a transfer station and
contracting for disposal in an out -of -County landfill as well as examining the
feasibility of alternatives.
Traditional waste processing technologies now in operation have the potential of
managing most of the County's non - recycled waste. Generally, WTE plants reduce
the processed waste tonnage by 75 percent and the volume by 90 percent. This
leaves a residue, ash, which needs to be landfilled in a permitted Subtitle D landfill.
In some states, ash may be used beneficially as alternative daily cover at landfills.
Even at 75 percent reduction by weight, a WTE facility has a dramatic effect on the
amount of residual waste.
This report examines both proven and unproven waste processing technologies.
Table A -2 in the Appendices provides a comparison of these various technologies.
Waste -to- energy (WTE) technologies profiled include: mass - burn /waterwall
combustion, mass - burn /modular combustion, refuse - derived fuel (RDF) /dedicated
boiler, and RDF /fluid bed. Although WTE plants range in size from 10 to 3,000 TPD
in the U.S., 71 percent are 500 TPD or larger. Mass - burn /waterwall combustion is
the most prevalent WPT in the U.S., employed at 65 of the 89 facilities. However,
no new mass -burn WTE facilities have been built in the U.S. for over ten years. Ten
WTE facilities currently operate in the Mid - Atlantic States region, processing almost
12,000 TPD. In North Carolina, New Hanover County owns a 500 TPD plant that
produces electricity. In contrast to its smaller presence in the U.S., WTE is an
accepted and commonly used waste processing technology worldwide, with 400
facilities in Europe, 100 in Japan, and 70 in other nations such as Taiwan, Singapore,
and China.
In addition to proven technologies, this report examines the emerging technologies
of high- temperature gasification, fluidized -bed combustion, plasma -arc processing,
non - thermal anaerobic digestion, and biological fuel production. Although technically
not an emerging technology, biological fuel production has not been commercially
proven using MSW as a feedstock.
The historical and current context for development and use of WTE in the U.S. is
explored, with waste processing technologies currently receiving renewed interest
due to: the proven WTE track record, increasing fossil fuel costs, growing interest in
renewable energy, a higher ranking in the EPA's waste management hierarchy,
GBB /C08027 -01 ES -1 August 15, 2008
concern about greenhouse gases, a change in flow control legislation, and the
increasing cost of long distance transfer and disposal.
Recent activity in the evaluation and procurement of WPT by other U.S. cities and
counties is detailed. Like Orange County, these localities are exploring alternatives
for service to their citizens. Information on the investigations of New York City, the
City of Los Angeles, Los Angeles County, and King County, WA into the applicability
of WPT is highlighted. Current WPT procurements are outlined, including: a resource
recovery facility for Frederick and Carroll Counties, MD; expansion of the Harford,
MD WTE facility; negotiations by the City of Sacramento, CA for a plasma gasification
project; Broward County, FL's Request for Expressions of Interest to evaluate
potential waste disposal options; a plasma arc gasification project proposed in St.
Lucie County, FL; and WTE plant expansions in Hillsborough and Lee Counties, FL,
that are currently being constructed. A total of 80 technology vendors offering 14
different technologies are represented, evaluated, screened, or selected during these
research and procurement projects.
The economic characteristics of the various waste processing technologies, including
capital and operating costs and risk, are summarized in the report. Generally,
capital cost for the proven technologies are in the range of $150,000 to $250,000
per ton of installed capacity, depending on size and plant configuration. Operating
costs are in the range of $35 to $60 per ton processed, not including residue
disposal, again dependent on size, equipment and operating profile, and assuming a
private operator. These figures are based on industry rules -of- thumb, recent
operating results from selected facilities, surveys of industry professionals and
related references.
Of the waste processing technologies examined, only WTE is a proven technology
which could be recommended for implementation consideration by Orange County at
this point in time. As mentioned earlier, there are 89 WTE plants generating power
in the U.S. and hundreds worldwide. The other technologies discussed are in various
stages of development and are not mature enough to mitigate the risks potentially
inherent with their implementation.
In evaluating waste processing technologies for Orange County to consider, it is
apparent that there is not enough waste generated by the County to gain the
economies of scale necessary to make a waste processing technology a cost - effective
investment. The estimated cost to process waste at a 300 TPD WTE facility in
Orange County is estimated at $102 per ton. To improve the economics of utilizing
waste processing technology, Orange County would need to partner with an adjacent
community. The $102 per ton is not competitive with the County's current landfill
disposal fee of $49 or with Waste Industries' cost of $42 per ton to transfer and
dispose of waste.
Although currently unknown, the cost of the County's new transfer station and
landfilling at a remote site is unlikely to reach $102 per ton. As the County
investigates the cost of transfer and disposal in preparation of its landfill closing,
WPT could be more economically attractive once the cost of transfer and disposal is
known. If $102 per ton were to look competitive, it is recommended that Orange
County conduct a WTE plant feasibility study which considers mass -burn modular
technologies, and /or fuel production approaches.
GBB/C08027 -01 ES -2 August 15, 2008
1.0 Introduction and Background
The federal government regulates solid waste in the United States under Title 40 of
the Code of Federal Regulations Subchapter 1 (40 CFR 239 to 2999). These
regulations are in 40 CFR 258 (also known as Resource Conservation Recovery Act
[RCRA] Subtitle D), Criteria for Municipal Solid Waste Landfills. Under authority of
RCRA, the United States Environmental Protection Agency (U.S. EPA) administers
Title 40 regulations and enforces solid waste regulations and policies through its
Office of Solid Waste (OSW).
Figure 1 -1 shows U.S. EPA's hierarchy of integrated solid waste management which
is illustrated in the form of a pyramid of ranked approaches. Source Reduction is at
the highest level (A) of the pyramid with landfilling at the bottom. Recycling
comprises the middle blocks (B & C) followed by combustion with energy recovery
(D) above combustion without energy recovery and landfilling (E).
Figure 1 -1 — Solid Waste Management Hierarchy'
A \ I Source Reduction and Reuse
Composting
B
c
U U
m Materials Recovery
C
D1
Processing /Combustion with Energy
Recovery
E
Landfilling and Incineration
without Energy Recovery
A +B +C +D +E= Capacity
(Not to Scale)
As Orange County updates its Solid Waste Management Plan en route to achieving
their goal of 61 percent waste reduction, the County should consider pursuing the
first two approaches: source reduction /reuse and recycling. Such activities include
the County's support of local recycling and the encouragement of yard waste
composting. As of 2006 -07, a reported 47.7 percent waste reduction rate was
achieved by the County, eliminating the need to landfill that portion of the waste
stream. The portion of waste generated that is not recycled or composted is hauled
' U.S. EPA.
GBB/C08027 -01 1 August 15, 2008
to the Orange County Landfill or out -of -county facilities. The County owns the local
municipal solid waste (MSW) landfill which is expected to reach capacity in the next
few years. A new County construction and demolition waste landfill area was
recently developed and is expected to last approximately 15 -20 years depending on
rate of use.
Another solid waste management strategy the County may want to consider is third
in the hierarchy: waste processing to reduce the volume for land disposal. While
waste processing technologies (WPT) can include methods of volume reduction
(shredding, compaction, baling, etc.), most such technologies involve some form of
controlled thermal treatment - incineration - with fuel production or energy
recovery. The County may want to consider the need to address such waste
processing technologies as possible alternatives to landfill disposal. The capital
intensive approaches such as WTE require a sufficient quantity of waste to be cost
effective: the more waste, the lower the per ton price.
The purpose of this white paper is to initiate that evaluation and brief the County's
solid waste staff, elected officials, Solid Waste Advisory Board, and citizens on state -
of- the -art solid waste processing technologies, emerging technologies and their
applicability to the County's needs, and the potential of these technologies to
contribute to the County's overall solid waste management system. Section 2.0
summarizes the future waste disposal needs identified in the Plan and how waste
processing could affect the amount of landfill disposal required.
Section 3.0 discusses the worldwide experience of WPT and respective vendors in the
United States and other countries, as some of these technologies have operating
demonstrations or facilities outside of the U.S. Section 4.0 reviews most of the
recent activity in the evaluation and procurement of waste processing technologies
by other U.S. cities and counties. These localities are exploring alternatives for
increasing their diversion rates, recovering more resources from their solid waste,
and delivering better service to their citizens. Section 5.0 explores the economic
feasibility, effectiveness, and environmental issues surrounding the use of the waste
processing technologies discussed. Section 6.0 presents opinions as to the most
applicable technologies for further consideration by the County.
Appendix B reviews the available "proven" waste processing technologies, all of
which are incineration - based, their track record and operating characteristics, and a
listing of facilities operating in the region. In addition, Appendix B details "emerging"
waste processing technologies including high- temperature gasification, fluidized -bed
combustion, plasma -arc processing, and some non - thermal anaerobic digestion.
GBB /C08027 -01 2 August 15, 2008
2.0 Future Orange County Waste Disposal Needs
Based on current data, the County (excluding recycled material from the University
of North Carolina (UNC)) generated approximately 116,000 tons of waste in FY
2006 -07 or about 318 tons per day (TPD). Of that material, approximately 15,600
tons or 42 TPD were captured recyclables. Approximately 16,500 tons of material
were buried in a construction and demolition waste (C &D) landfill located in Orange
County and 8,700 tons of C &D were shipped for disposal out of the County. Tires,
clean wood, brush, appliances and scrap metal totaling 12,300 were also recycled in
2006 -2007. That leaves approximately 62,900 tons of waste or 172 TPD from
Orange County disposed in landfills both inside and outside the County. This
tonnage could be further reduced with additional diversion programs.
The County is examining ways to achieve its goal of 61 percent waste reduction. As
part of this solid waste planning process update, the County has developed a series
of reports evaluating current collection programs, looking at ways to increase
diversion and deliver services more efficiently and effectively. These reports will be
followed by technical reports on integrating the desired actions into the County's
system and financing, which will result in a draft plan for the next three year
planning cycle.
The County's MSW landfill is now projected to close in early 2011. The County has
decided to manage its future MSW using a transfer station and contracting for
disposal in an out -of -County landfill. A County-wide search is underway for a
suitable site to situate the transfer station with site selection expected by the end of
2008. Following site selection, the County will design, permit, finance, and construct
the transfer station, ideally before landfill closure. If the transfer station is not
completed by the time the landfill is closed, managing MSW during that time period
will be expensive and operationally challenging.
The projected landfill closure date may be impacted by new rules governing what
was formerly considered C &D. This material must now be disposed of in lined landfill
space. As of April 2008, stricter enforcement of the rules governing C &D landfills
require the County to deposit furniture and other bulky items in the lined MSW
landfill. This may result in a shift of as much as 8,000 tons of waste a year from
C &D landfills to MSW landfills, shortening the life expectancy of the County's MSW
landfill by as much as five months.
As it is, the County- generated 172 TPD is probably too small to make an alternative
waste processing technology economically viable. However, the Durham
Metropolitan Statistical Area, which includes Chatham, Durham, Orange, and Person
Counties, had a population of 465,745 people who generated 476,710 tons of
municipal solid waste from July 2006 - June 2007, according to the FY 2006 -2007
North Carolina Department of Environment and Natural Resources Solid Waste
Annual Report. Of that 476,710 tons of waste, an estimated 90,575 tons or 19
percent2 constitutes recyclables. The resulting 386,135 of MSW could translate into
2 Simmons, Phil; Goldstein, Nora; Kaufman, Scott M.; Themelis, Nickolas J.; and Thompson,
Jr., James. "The State of Garbage in America." Biocycle, April 2006: 26.
<http://www.jgpress.com/archives/_free/000848.htmI>.
GBB/C08027 -01 3 August 15, 2008
approximately 1,000 TPD available regionally to make an alternative technology
more economically viable.
Traditional waste processing technologies now in operation have the potential of
managing most of the residual waste. Generally, WTE plants reduce the incoming
waste stream tonnage by 75 percent and the volume by 90 percent. This leaves a
residue, ash, that needs to be landfilled in a permitted Subtitle D landfill and in some
states ash is used as alternative daily cover. Some emerging technologies could
reduce the residual tonnage of the waste stream even further, but those haven't yet
been proven in the U.S on a large scale. Even at 75 percent reduction by weight, a
WTE facility has a dramatic effect on the amount of residual waste.
GBB/C08027 -01 4 August 15, 2008
3.0 Worldwide Experience of Waste Processing
Technologies and Vendors
A variety of WPT are discussed in Appendix B and a summary matrix is in Appendix
A, Table A -2. This section discusses the past and current experience of WPT in the
U.S. and elsewhere.
3.1 Mass - Burn /Waterwall Combustion
No new mass -burn WTE facilities have been built in the United States for the past ten
years, although there have been acquisitions and ownership and operator changes at
certain existing facilities, as well as some plant expansions. As a result, the firms
associated with mass -burn WTE are operators, owners, or owner /operators of
existing facilities. As shown in the Table 3 -1, Covanta and Wheelabrator own and
operate the majority of privately -owned WTE facilities. Most of the WTE plants, both
public and private, are operated by Covanta, Montenay/Veolia or Wheelabrator.
Table 3 -1 also shows the range in tons processed per day between facility owners
and operators, with publicly operated facilities processing smaller amounts of waste
than those operated privately.
Table 3 -1. U.S. Mass - Burn /Waterwall Facilities3
Entity
Owned
Tons processed
per day
Operated
Tons processed
per day
Public
39
200-3,000
12
200-500
Covanta
11
400-3,000
27
400-3,000
Montena eolia
2
500- 1,200
9
500-3,000
Wheelabrator
10
200-2,250
16
200-2,250
Other
3
550-2,250
1
200-1,380
Total
65
65
Some of the mass -burn technology had been purchased from American firms such as
Detroit Stoker, Combustion Engineering and Babcock & Wilcox, but the majority of
these existing systems are of European design. The two leading suppliers of WTE
grate systems in the United States and overseas are The Martin Company of
Germany and Von Roll of Switzerland.
While new WTE facility procurements have declined in the United States, the market
for this equipment has increased in Europe and in Eastern Asia, with European and
Japanese systems suppliers actively marketing their systems, and consistently
improving their performance. This technology is well tested and is used more than
any other for large WTE facilities in the United States and overseas.
3.2 Mass - Burn /Modular Combustion
Modular systems are used for smaller WTE facilities (between 80 - 360 TPD) and for
industrial applications. Unlike mass burn /waterwall systems, there are a number of
American firms supplying such systems in the United States, and they are very
competitive in overseas markets as well. The more active of these suppliers are
Consutech Systems of Richmond, Virginia, Enercon Systems, Inc. of Elyria, Ohio, and
3 Integrated Waste Management Services Association, 2004 Directory of WTE Plants.
GBB /C08027 -01 5 August 15, 2008
Basic Environmental Engineering of Chicago. They have each been supplying
incineration systems for MSW and other wastes for over 25 years.
Other U.S. firms, such as Energy Answers of Albany, NY, and Covanta Energy of
Fairfield, NJ, are marketing project development and management services for WTE
modular facilities.
3.3 Refuse - derived Fuel /Dedicated Boiler
As with mass -burn systems, there have not been any new Refuse - derived Fuel (RDF)
systems constructed in the United States in the past decade. For most of the 12 RDF
WTE facilities currently in operation, Excel, Veolia and Covanta Energy are the
operating contractors. The front -end processing utilizes a variety of unit processes
depending upon the boiler requirements and the design philosophy. The unit process
equipment, shredders, magnetic separators, screens, conveyors, etc., are all
standard items available from a variety of manufacturers.
Equipment used in this technology is adapted from equipment provided in coal -fired
electricity generation plants, and there are many established system and equipment
suppliers marketing in the U.S., such as Foster Wheeler, Riley, Babcock and Wilcox,
Detroit Stoker, ABB and Wartsila.
3.4 RDF /Fluidized Bed
While there are several RDF /fluid bed systems operating in Europe (particularly in
Scandinavia, where a number of fluid bed incinerator manufacturers are located),
there is only one such facility in operation in the United States, located in French
Island, WI. It is owned and operated by Excel Energy of Minneapolis. The
equipment was supplied by Energy Products of Idaho in Coeur d'Alene, the only U.S.
firm currently manufacturing these furnaces for RDF firing.
3.5 Gasification
Japan currently has seven plants operating with gasification technology. At least two
of these facilities fire MSW, with the largest firing up to 700 TPD of MSW. In Europe
and Asia, approximately 20 syngas gasification facilities are operating on MSW. Most
of these facilities are relatively small, processing less than 10 TPD with none
designed to process more than 70 TPD.
3.6 Pyrolysis
With pyrolysis, MSW is heated in an oxygen- starved environment to produce a fuel
gas that is then incinerated to generate steam and /or electricity. In the 1970s, a
number of pyrolysis facilities were constructed using MSW as a feedstock. Several
were built with partial funding provided by U.S. EPA. The largest of these was the
Monsanto facility in Baltimore, MD, which had a capacity of 1,000 TPD. This facility
did not meet its environmental requirements due to operational scale -up problems
and was torn down. Other smaller, 100 to 200 TPD, MSW pyrolysis facilities were
built at that time by Union Carbide, Anco Torrax, and Occidental Petroleum. These
facilities were recipients of U.S. EPA grant funds and were closed for operational and
financial reasons. Currently, there are no full -scale pyrolysis systems in commercial
operation on MSW in the United States. A pilot demonstration system has been
GBB/C08027 -01 6 August 15, 2008
operating in southern California for two years. It was built and is operated by
International Environmental Solutions, of Romoland, CA.
3.7 Plasma Arc
The plasma arc furnace is a commercial unit process made and marketed by
Westinghouse. It has been successfully applied to a variety of industrial
applications; however, there are no commercial -scale plasma arc systems firing MSW
in the United States at the time of this report. There are pilot plants used for ash
vitrification in Japan and a smaller Japanese facility firing MSW, but attempts to
apply this process in the United States have not yet been successful. However,
several vendors are advancing projects as described earlier. The electric power
requirements for the torch are significant, and maintenance of torches and reactor
refractory materials is also a significant expense item.
Few, if any of the plasma arc pilot facilities have been able to generate a fuel gas
(syngas), and air emissions have been found to be no better than conventional
incineration systems. The Atlanta firm Geoplasma has a development contract and is
negotiating a contract for implementation of a large plasma arc facility for MSW in
St. Lucie County, Florida, which will also to be used for processing mined landfill
waste. The City of Tallahassee, Florida approved the contract for Green Power
Systems to begin development of a 1,000 TPD plasma gasification plant, which is
scheduled to begin operations in 2010.
3.8 Biological Fuel Production
3.8.1 Cellulosic Ethanol
There are a number of commercial facilities in the U.S. (See Table 3 -2) and
worldwide producing cellulosic ethanol, a biofuel produced from lignocellulose, a
structural material that comprises much of the mass of plants. These facilities utilize
a variety of biomass feedstocks. Biomass is any living or recently dead biological
material that can be used as fuel or for industrial production. Biomass feedstocks
include crops grown specifically for use as a feedstock, such as corn or hemp,
agricultural residues, and other organic residues and wastes, including the organic
portion of MSW. At the time of this report, no U.S. facilities are feeding MSW but a
number of vendors are planning to use MSW as a feedstock.
Abengoa Bioenergy owns and operates five cellulosic ethanol facilities throughout the
United States and Europe with a total production capacity of over 200 million gallons
annually. It is currently the fifth largest producer of cellulosic ethanol in the United
States with a total of four plants located in Kansas, New Mexico, and Nebraska. The
most recent began operations in mid 2007, bringing Abengoa Bioenergy's nameplate
capacity to more than 200 million gallons per year in the U.S. In addition, Abengoa
Bioenergy operates four plants in Europe.
The world's first commercial scale demonstration biomass plant is being constructed
by Abengoa Bioenergy to exhibit its biomass -to- ethanol process technology. Located
in Babilafuente (Salamanca), Spain, the biomass plant will process 77 tons of
agricultural residues, such as wheat straw, each day and produce over 1.3 million
gallons of fuel grade ethanol per year. Bioethanol is most currently used in Brazil,
where longstanding policies promote and encourage the use of bioethanol as fuel for
transportation.
GBB/C08027 -01 7 August 15, 2008
CleanTech Biofuels has a cellulosic ethanol pilot plant operating on MSW in Golden,
Colorado.
Table 3 -2. Commercial Cellulosic Ethanol Plants in the U.S.
(Operational or Under Construction)4
Company
Location
Feedstock
Capacity
(million
gallons
per year)
Aben oa Bioeneray
Hu oton KS
Wheat straw
12
Alico
La Belle FL
Multiple sources
N/A
BlueFire Ethanol
Irvine CA
Multiple sources
17
Gulf Coast Energy
Mossy Head FL
Wood waste
70
Mascoma
Lansing, MI
Wood
40
POET Biorefinery
Emmetsburg, IA
Corn cobs
25
Range Fuels
Treutlen County, GA
Wood waste
20
SunO to
Little Falls MN
Wood chips
10
Xethanol
Auburndale FL
Citrus peels
8
None of these plants uses MSW as feedstock. As of January 2008, U.S. DOE had
made seven grants to help develop small -scale cellulosic plants. These plants will
produce between 1.3 and 5.5 million gallons of ethanol per year. The feedstocks
projected for these plants include wood chips, switch grass, corn cobs, and
agricultural and forest residues. None of the plants are projected to use MSW. The
total projected capital cost of these plants is $634 million, with DOE contributing
$199 million in the form of the grants.
3.8.2 Biogas - Anaerobic Digestion
Biogas or synthesis gas, a mixture of carbon monoxide and hydrogen, can be
converted into liquid hydrocarbons of various forms. A number of these technologies
produce gas, primarily methane, which can be converted to liquid fuels utilizing
Fischer - Tropsch Synthesis, a process developed in Germany in the early 20th
Century. This process is a catalyzed chemical reaction which takes place at low
temperatures (300 to 600 degrees F) and at high pressure. The most common
catalysts are based on iron and cobalt, although nickel and ruthenium have also
been used. The process produces a synthetic petroleum substitute for use as
synthetic fuel, biodiesel. The Fischer - Tropsch process has been used to convert
gases from a variety of feedstocks to liquid fuel, including coal and biomass.
When biomass is used, the cellulosic materials must first be converted to biogas and
then to liquid fuel using the Fischer - Tropsch process.
Currently, a number of companies have commercial versions of the Fischer - Tropsch
technology, including:
1. Conoco - Phillips- natural gas as feedstock
2. BP- natural gas as feedstock
3. Shell Oil - natural gas as feedstock
4. Sasol (South Africa) - coal and natural gas as feedstocks
4 Source: Grainnet.com Building Cellulose
GBB/C08027 -01 8 August 15, 2008
5. Rentech (U.S.) - coal or coke as feedstock
6. Choren Industries (Germany) -
7. Syntroleum (U.S.) - used natural gas as feedstock in a demonstration for the
U.S. Air Force.
In addition, there are a number of research projects funded by the U.S. Department
of Energy to use organic materials as feedstocks. These include the Renewable
Energy Laboratory and Louisiana State University.
The Fischer - Tropsch process is an established technology that has been applied on a
large scale in some industrial sectors. Large -scale commercialization is impeded by
high capital costs, high operation and maintenance costs, the uncertain and volatile
price of crude oil, and environmental concerns.
As mentioned in Appendix B, Section 1.3.2, biogas production from wastes is a
mature technology with both large- and small -scale units in production worldwide.
In India alone, there are over 2 million farm units that produce biogas from animal
manures and other wastes. As of 2006, there were thousands of plants in Europe;
Germany alone had 3,500 that produced a total of 1,100 MW. The newest of these
plants range between 400 and 800 KW, using crops and manure for feedstock. In
southern Europe, the production of biogas is primarily from landfills. In 2007, a
report on the potential of biogas in Europe by the Oko- Instituts and the Institut fOr
Energetik in Leipzig concluded that Germany alone can produce more biogas by 2020
than all of the European Union's (EU) current natural gas imports from Russia.
Table 3 -3 shows the production of biogas in Europe by country with the production
broken into three categories of feedstock: landfill gas, sewage sludge and other.
Summarized by feedstock, this results in 64 percent landfill gas, 18.8 from sewage
sludge and 17.2 other. The largest producer of biogas is the United Kingdom, closely
followed by Germany. The biogas is approximately 50 percent methane, mixed with
carbon dioxide and other gases.
GBB /C08027 -01 9 August 15, 2008
Table 3 -3. Biogas Production in Europe
(KTOE = thousand tonnes of oil eouivalent)
'Estimation Source: EurObser /ER 2006 Note: 1 KTOE is equal to $11.63 MWh.
The biogas sector is booming in Germany and has become the continent's fastest
renewable energy sector. The growing interest is due to three factors: it can be
produced in a decentralized manner, it is highly efficient - yielding more than twice
as much energy per acre of energy crops than ethanol from similar crops, and it can
be obtained using known processes from a large variety of biomass resources
(organic waste, manure, dedicated energy crops). The biogas can be used as
produced as a medium Btu fuel, or it can be processed to produce a pipeline quality
gas which is almost pure methane. Also, the biogas has two highly efficient uses: as
a gas for compressed clean natural gas (CNG)- capable vehicles and as a fuel that
can be used for the cogeneration of power and heat. Meanwhile, advances in biogas
technology, microbiology and crop engineering have made production even more
efficient.
A number of established firms compete for the biogas plant construction and
operation in Europe. Each has developed its own proprietary process, and some are
50 years old or older. There are over 200 operating plants, as shown in Table 3 -4.
Table 3 -4. Biogas Firms in Europe
2004
2005*
Countries
Landfill
Gas
Sewage
Sludge Gas
Other
Biogas
Total
Landfill
Gas
Sewage
Sludge Gas
other
Biogas
Total
K
1326.7
165.0
-
1491.1
1617.6
165.0
-
1782.6
Wet and dry
573.2
369.8
351.7
1294.7
573.2
369.8
651.4
1594.4
Ita
297.7
0.3
37.5
335.5
334.1
0.4
42.0
376.5
in
219.1
52.4
23.6
295.1
236.5
56.8
23.6
1 316.9
rance
127.0
77.0
3.0
207.0
129.0
77.0
3.0
1 209.0
etherlands
48.7
48.6
28.9
126.2
48.7
48.6
28.9
1 126.2
35.8
69.3
105.1
35.8
69.3
105.1
mark
13.8
19.8
55.6
89.3
14.3
20.5
57.5
92.3
ium
56.3
9.7
7.8
73.8
56.3
9.7
7.8
73.8
zeoh R
18.6
28.7
2.9
50.2
21.5
31.4
2.8
55.8
oland
21.5
23.9
-
45.4
25.1
25.3
0.3
50.7
tria
11.8
19.1
14.5
45.4
11.8
19.1
14.5
45.4
reeve
20.5
15.5
36.0
20.5
15.5
36.0
Ireland
19.9
4.8
5.1
29.9
24.9
4.8
5.1
34.8
inland
16.6
9.9
26.5
16.6
9.9
26.5
al
4.5
4.5
10.0
10.0
ovenia
5.8
0.9
-
6.6
6.0
0.7
6.8
emu
-
-
5.0
5.0
-
-
6.7
6.7
ovakia
-
5.7
0.2
5.9
-
5.7
0.2
5.9
u ary
0.7
2.6
0.2
3.5
0.8
2.9
0.2
3.8
U
2813.8
922.9
540.5
4277.2
3172.7
932.4
854.0
4959.1
'Estimation Source: EurObser /ER 2006 Note: 1 KTOE is equal to $11.63 MWh.
The biogas sector is booming in Germany and has become the continent's fastest
renewable energy sector. The growing interest is due to three factors: it can be
produced in a decentralized manner, it is highly efficient - yielding more than twice
as much energy per acre of energy crops than ethanol from similar crops, and it can
be obtained using known processes from a large variety of biomass resources
(organic waste, manure, dedicated energy crops). The biogas can be used as
produced as a medium Btu fuel, or it can be processed to produce a pipeline quality
gas which is almost pure methane. Also, the biogas has two highly efficient uses: as
a gas for compressed clean natural gas (CNG)- capable vehicles and as a fuel that
can be used for the cogeneration of power and heat. Meanwhile, advances in biogas
technology, microbiology and crop engineering have made production even more
efficient.
A number of established firms compete for the biogas plant construction and
operation in Europe. Each has developed its own proprietary process, and some are
50 years old or older. There are over 200 operating plants, as shown in Table 3 -4.
Table 3 -4. Biogas Firms in Europe
Source: EurObser /ER 2006
GBB/C08027 -01 10 August 15, 2008
Waste
Number of
Total
Firms
Countries
System
Types
Plants
Capacity
Tons Year
Linde AG Wies -baden
Germany
Linde BRV KCA
Wet and dry
4
1 000 000
Kom o as AG
Switzerland
Kompoclas
Dry
24
4416%0
Organic Waste Systems
Belgium
Dranco
Dry
14
750,000
Schmack Biogas AG
German
Euco Coccus
Wet
Approx. 100
Unknown
Valorcia International SAS
France
Valor a
Dry
12
1,047,000
Biotechnische Abfallverwertung
Germany
BTA
Wet
27
624,500
GmbH & Co KG
Source: EurObser /ER 2006
GBB/C08027 -01 10 August 15, 2008
Now, producers in Germany want to feed their upgraded biogas, also known as
biomethane, into the main natural gas grid across the EU. However, they face the
significant barrier of their purified biogas not meeting the industry standard for
pipeline gas. At 1,100 btu per cubic foot, biomethane's heating value is too high
compared to the industry standard of 900 btu per cubic foot. Germany is the only
country in Europe to impose an upper quality limit on gas. The German Greens and
the country's environmentalists and farmers are therefore asking for a new law that
allows producers to feed their superior, renewable and green gas into the national
pipelines.
GBB/C08027 -01 it August 15, 2008
4.0 Recent Research/ Procurements for Waste
Processing Technologies by Others
The most recently constructed MSW- processing WTE facility in the U.S. commenced
operations in 1996.5 Since that time, no commercial plant has been implemented.
Several reasons account for this lull of activity in the WTE field:
1. Loss of Tax Credits - The 1986 Tax Reform Act eliminated the significant tax
benefits for project owners /developers, contributing to the pipeline of
projects.
2. Environmental Activism - Misinformation about air pollution and ash impacts,
and preferences for recycling, created public resistance.
3. U.S. Supreme Court's Carbone Decision (1994) - Effectively ended legislated
flow control, creating uncertainty in the revenue stream for projects.
4. Megafills - Large landfills with low tipping fees and no put -or -pay waste
supply requirement out - competed WTE for the market.
5. Amendment to the Clean Air Act (1998) - New regulations required retrofit on
existing plants and drove up WTE costs, effective as of December 2000.
6. Lack of Federal Leadership (1990 - 2005) - Visible opposition by U.S. EPA to
combustion and preference for waste reduction /recycling sent negative
message about WTE.
7. Moderate Fossil Fuel Costs - The rapidly, increasing fossil fuel costs of the
1970s and '80s stabilized, reducing the value of the energy products from
WTE facilities, which were key drivers in facilities developed earlier, and
making overall project economics less attractive.
In the past few years, however, interest in WTE and waste conversion has begun to
grow again. This renewed interest in waste processing technologies is due to several
factors:
1. Proven WTE Track Record - superior environmental performance, reliability,
advancements in technology and successful ash handling strategies have
made WTE an acceptable option to consider as part of waste management
planning.
2. Increasing Fossil Fuel Costs - With the price of oil now over $120 per barrel,
the cost of transportation fuels is making MSW hauling and landfilling more
expensive. In addition, the cost of electricity from fossil fuels is increasing,
making electricity from waste more valuable and making WTE more
competitive.
3. Growing Interest in Renewable Energy - Many States are requiring utilities to
generate a portion of their electricity from renewable sources, which
sometimes includes WTE; the Federal government has included WTE in its
definition of renewable energy.
4. Change in Approach by U.S. EPA - In 2006, the U.S. EPA revised its waste
management hierarchy to include WTE explicitly as the third priority after
waste reduction and recycling /composting.
5 Covanta's 2,250 TPD plant in Niagara Falls, NY.
6 C & A Carbone, Inc. M. Town of Clarkstown, 511 U.S. 383 (1994).
GBB/C08027 -01 12 August 15, 2008
5. Concern About Greenhouse Gases - WTE has a smaller carbon footprint than
landfilling or fossil -fuel generated electricity'.
6. Reversal of Carbone - The 2007 Supreme Court decision in the Oneida -
Herkimer case effectively restored to city and local governments the ability
to implement flow control, increasing the security of the waste stream to
support the financing of WTE projects.
7. Long distance transfer and disposal getting more expensive.
These and other local considerations have led a growing number of communities to
re- investigate waste processing technologies as a component of their solid waste
management systems. The following sections describe several of the recent
initiatives to evaluate and choose waste processing technologies - WTE and others -
to handle significant waste streams in the future. At the end of Section 4.0 is a
summary of the technologies and vendors selected through these evaluation
processes that represent the most promising alternatives for adopting WTE as a
waste disposal option.
4.1 Recent Research
4.1.1 New York City, NY9
In 2004, the City of New York commissioned a report to evaluate new and emerging
waste management and recycling technologies and approaches. The objective of the
evaluation was to provide information to assist the City in its ongoing planning
efforts for its waste management system. The report identified which innovative
technologies were available at present, i.e., commercially operational processing of
MSW, and which were promising but in an earlier stage of development. It also
compared the newer technologies to conventional WTE technology to identify the
potential advantages and disadvantages that may exist in the pursuit of innovative
technologies. Conventional WTE was chosen as a point of comparison since such
technology was the most widely used technology available at the time for reducing
the quantity of landfilled post - recycled waste.
The report was released in September 2004. 44 companies responded to the initial
request for information. The City has commenced a siting Task Force to look at the
five boroughs to identify a site on which to build a pilot facility. Once the site has
been identified, an RFP will be issued based on the specifications and condition of the
site and will be made available to all proven and unproven technology vendors.
As part of the process, the City collected information on capital cost from the
suppliers. Based on six responses, the capital cost per installed ton for anaerobic
digestion ranged from $74,000 (586 TPD) to $82,000 (500 TPD); for gasification, the
range was $155,000 (2,612 TPD) to $258,000 (2,959 TPD); one plasma arc
gasification response gave a capital cost of $321,000 (2,729 TPD). These figures
were for plants of widely varying sizes and were not standardized.
7 Thorneloe, Susan A., Weitz, Keith A., Nishtala, Subba R., Yarkosky, Sherry, and Zanes,
Maria. "The Impact of Municipal Solid Waste Management on Greenhouse Gas Emissions in
the United States." Journal of the Air & Waste Management Association 52 (September
2002) : 1000 -1011.
8 United Haulers Assn., Inc. M. Oneida - Herkimer Solid Waste Management Authority, No. 05-
1345, 2007 WL 1237912 (U.S. April 30, 2007).
9 Evaluation of New and Emerging Solid Waste Management Technologies, September 16,
2004.
GBB/C08027 -01 13 August 15, 2008
4.1.2 City of Los Angeles, CA
Phase Iio
In 2004, the City of Los Angeles, Bureau of Sanitation (Bureau) began a study to
evaluate MSW alternative treatment technologies capable of processing Black Bin
material (curbside - collected residential MSW) to significantly reduce the amount of
such material going to landfills. The Bureau's overall objective was to select one or
more suppliers to develop a facility using proven and commercialized technology to
process the Black Bin material and produce usable by- products such as electricity,
green fuel, and /or chemicals.
The first step of this project was to develop a comprehensive list of potential
technologies and suppliers. About 225 suppliers were screened, and 26 suppliers
were selected to submit their detailed qualifications to the City. In order to screen
the technology suppliers, they were sent a brief survey based upon the technology
screening criteria. The criteria applied were as follows:
• Waste Treatability: The supplier was screened on whether they have MSW or
similar feedstock processing experience.
• Conversion Performance: The supplier was asked if their facility would
produce marketable byproducts.
• Throughput Requirement: This criterion was already met because the
technology passed the technology screen.
• Commercial Status: This criterion was already met because the technology
passed the technology screen.
• Technology Capability: The supplier was asked if their technology had
processed at least 25 tons per day of feedstock.
Of the 26 suppliers requested to submit qualifications, seventeen provided
responses. These suppliers and their technologies were thoroughly evaluated, and
an Evaluation Report was published in September 2005 with the findings and ranking
of the 26 suppliers' technologies that had met the criteria.
A Request for Qualifications (RFQ) was prepared and provided to the suppliers that
met the screening criteria. A detailed technical and economic evaluation of the
suppliers that responded to the RFQ was completed. This resulted in the
development of a short list of alternative treatment technology suppliers. In 2006,
several suppliers were added to the short list, based on additional screening and a
supplemental RFQ process.
As part of the process, the City collected information on capital cost from the
suppliers. Based on 18 responses, the capital cost per installed ton for anaerobic
digestion ranged from $99,000 to $201,000; for gasification, the range was $50,000
to $266,000; for pyrolysis, the range was $60,000 to $221,000; one mixed waste
io Request for Proposals for a Development Partner(s) for Processing Municipal Solid Waste
Utilizing Alternative Technologies premised on Resource Recovery for the City of Los Angeles,
February 5, 2007.
GBB/C08027 -01 14 August 15, 2008
composting proposer gave a capital cost of $114,000. These figures were for plants
of widely varying sizes and were not standardized.
Phase II11
On February 7, 2007, the City of Los Angeles released a Request for Proposals (RFP)
soliciting competitive proposals for a development partner(s) for processing MSW
utilizing alternative technologies premised on resource recovery. The responsibilities
of the development partners were to finance, design, build, own, and operate (with
the option to transfer to the City after 20 years) the resource recovery facility, at a
throughput rate of 200 -1,000 TPD. The facility was expected to provide diversion
from landfill of no less than 80 percent of the City's Black Bin (waste) material
delivered to the facility. In addition, the City considered proposals from
emerging /experimental technologies that could process less than 200 tons per day
as a potential second facility for testing emerging technologies. The
emerging /experimental technology suppliers were to meet requirements outlined by
the City in the RFP in order to be considered for the potential testing facility.
Proposers of emerging /experimental technologies that did not meet those
requirements were not evaluated further. A total of 12 technology
suppliers submitted applications in August 2007. The City of Los Angeles' Bureau of
Sanitation has reviewed the proposals and received presentations by the proposers.
The Bureau has conducted site analyses and visits to all facilities and is putting
together a recommendation by December 2008 of the finalists to be further
evaluated.
Phase III
Phase III will start before the end of the year. It will include developing contracts for
selection and increasing the focus on public outreach.
4.1.3 Los Angeles County, CA
Phase I - Initial Technology Evaluation 12
Beginning in 2004, Los Angeles County conducted a preliminary evaluation of a
range of conversion technologies and technology suppliers, and initiated efforts to
identify material recovery facilities (MRFs) and transfer stations (TSs) in Southern
California that could potentially host a conversion technology facility. A scope of
investigation beyond Los Angeles County itself was considered important, as
stakeholders in the evaluation extended beyond the County and the implications of
this effort would be regional.
In August 2005, the evaluation report was adopted. Phase I resulted in identification
of a preliminary short list of technology suppliers and MRF/TS sites, along with
development of a long -term strategy for implementation of a conversion technology
demonstration facility at one of these sites. The County intentionally pursued
integrating a conversion technology facility at a MRF/TS site in order to further divert
post - recycling residual waste from landfilling and take advantage of a number of
beneficial synergies from co- locating a conversion facility at a MRF.
11 !bid.
12 Los Angeles County Conversion Technology Evaluation Report N Phase II - Assessment,
October 2007.
GBB/C08027 -01 15 August 15, 2008
Phase II - Facilitation Efforts for Demonstration FacilityD
In July 2006, the County further advanced its efforts to facilitate development of a
conversion technology demonstration facility. The approach was multi - disciplined,
including environmental analysis and constructability. Key Phase II study areas
included:
• An independent evaluation and verification of the qualifications of selected
technology suppliers and the capabilities of their conversion technologies;
• An independent evaluation of candidate MRF/TS sites, to determine suitability
for installation, integration and operation of one of the technologies;
• A review of the required permits to facilitate the project;
• Identification of funding opportunities and financing means;
• Identification of potential county incentives (i.e., supporting benefits) to
encourage facility development amongst potential project sponsors; and
• Negotiation activities to assist parties in developing project teams and a
Demonstration project.
The report described progress to date on Phase II, and represented a culmination of
approximately one year of work conducted by the County. Five companies were
issued Request for Offers (RFO) early in 2008 for a demonstration to be constructed
at any one of four sites by the selected vendor. The five conversion technology
suppliers considered and their corresponding technologies offered were: Arrow
Ecology utilizing anaerobic digestion; Changing World Technologies utilizing thermal
depolymerization; International Environmental Solutions utilizing pyrolysis;
Interstate Waste Technologies utilizing pyrolysis /gasification; and Ntech
Environmental utilizing gasification. Five materials recovery facilities (MRF) were
considered for partnering with the technology supplier. Only one MRF, Community
Recycling /Resource Recovery, Inc. MRF, is located in L.A. County. The Perris
MRF/Transfer Station and the Robert A. Nelson Transfer Station and MRF (RANT) are
located in Riverside County. Del Norte Regional Recycling and Transfer Station is
situated in Ventura County and the Rainbow Disposal Co. Inc MRF is in Orange
County.
Phase III - Evaluation and Presentation of Request for Offers
Phase III of the project is expected to be finalized by the end of 2008. At the time of
this report, the County had received several offers, with a deadline of August 15,
2008 for receipt. It appears that Changing World Technologies is no longer
participating and that the County is mostly working to locate these projects in
privately owned MRFs in Riverside and Orange counties. Phase III will include the
evaluation of these offers and the presentation of the results to the Board. Phase IV
of the project will begin in 2009.
13 ibid.
GBB/C08027 -01 16 August 15, 2008
4.1.4 King County, WA
A proviso to the 2007 King County Solid Waste Division budget required that the
Division prepare a comparative evaluation of waste conversion technologies (i.e.
WTE incineration) and waste export. After review and comment on the draft report
by the Metropolitan Solid Waste Management Advisory Committee (MSWMAC) and
others, the final report was submitted to the King County Council on August 6, 2007.
Based on the report, MSWMAC made the following recommendations to the Council:
1. That the King County Council continue its current policy course toward waste
export by implementing the recommendations in the Solid Waste Transfer and
Waste Export System Plan.
2. That every avenue to extend the life of the Cedar Hills Landfill be explored,
including increased recycling and partial early waste export, to keep solid
waste rates as low as possible for as long as possible and to provide
maximum flexibility for long -term planning.
3. That no further resources be expended on the study of incineration
technologies at this time. They believed that there was sufficient information
in the report to analyze waste export and incineration technologies at a
programmatic level in the Comprehensive Solid Waste Management Plan
update and its EIS.
There were concerns about the practicality of waste conversion technologies in the
King County region, and there was a need recognized to continue planning for the
existing transfer system and the potential of extending the life of the Cedar Hills
Landfill.
4.2 Procurements
4.2.1 Frederick and Carroll Counties, MD
In May 2006, the Northeast Maryland Waste Disposal Authority (Authority) began a
search for firms with Qualified Technologies to provide WTE facilities for Frederick
and Carroll Counties. The Authority was seeking technologies that demonstrated
success in the efficient and feasible conversion of MSW into marketable steam,
thermal energy, fuel and electricity. Technologies that produced a fuel were to be
considered if the fuel had been demonstrated to reliably and efficiently produce
energy (Qualified Technologies). The Authority conducted a two -step procurement.
The first step was the Request for Qualifications (RFQ) to identify firms with Qualified
Technologies. Qualified Technologies were to be eligible for consideration in the
second step, the Basis of Negotiation (BON). In order to be deemed a Qualified
Technology, operating statistics from a reference facility had to be provided, with a
minimum of three consecutive years of operating data, including waste processed,
energy produced, air emissions and residue generation.
The size of each unit could be as small as 100 TPD and as large as 750 TPD. The
selection of unit size for each project was to be determined during the BON phase.
The Authority understood that there were many new and emerging technologies
which convert MSW into various fuels or energy. However, the Authority is
dependent on bond financing for its projects, and the lending community insisted on
GBB/C08027 -01 17 August 15, 2008
proven technology as a minimum requirement for making capital available to the
Authority.
In October 2006, the Authority solicited Proposals from qualified, experienced firms
in the refuse management and power facility construction and operation fields to
provide for the construction, testing, operation and maintenance of a new refuse
power plant (RPP) capacity for the counties. The Authority had pre - qualified eight
technologies for this solicitation.
The facilities were to be owned by the Authority and leased to the successful
Proposer (Company) on a long -term basis (at least 20 years from the commercial
operations date). The site was to be provided by the Authority. The Authority would
provide most of the refuse (fuel) under a put -or -pay contract and would apply
residues for beneficial use as daily cover at the counties' landfills.
The Company would have the rights to all or a portion of the energy revenues (as
specified by it in its proposal) and all of the excess waste disposal capacity that could
be used to dispose of non - residential waste from any other Authority jurisdiction.
In response to the directives, proposals were requested for the following three
facility options:
• A 900 TPD resource recovery facility to be located in Frederick County to
process residential and commercial waste generated in Frederick County; and
• A 600 TPD resource recovery facility to be located in Carroll County to process
residential and commercial waste generated in Carroll County; or
A 1,500 TPD resource recovery facility to be located in Carroll County to
process residential and commercial waste generated in both Frederick and
Carroll Counties.
After receipt of proposals from three vendors, the Authority, in conjunction with the
participating jurisdictions, completed an initial review of the proposals and short-
listed Covanta Energy and Wheelabrator Technologies. As part of the initial review,
the Authority met with Covanta and Wheelabrator to clarify their proposals and to
ensure that the initial financial modeling results correctly represented their proposals
and met the needs of the local jurisdictions. As of the time of this report, the
Authority is currently seeking approvals from the jurisdictions to begin formal
negotiations with the vendors to arrive at a final contract to be voted on by the
jurisdictions' Commissioners. If approved by the jurisdictions, the permitting and
construction of the facilities could take up to five years.
4.2.2 Harford County, MD
In May 2006, the Northeast Maryland Waste Disposal Authority (Authority) began a
search for firms with Qualified Technologies to provide an expansion of the WTE
facility for Harford County, similar to the process conducted for Frederick and Carroll
counties (see 5.2.1 above).
In December 2006, The Authority issued a Request for Proposals (RFP) for a
Resource Recovery Facility (RRF) located in Harford County, Maryland. This was the
second step in the two -step competitive procurement being conducted by the
GBB/C08027 -01 18 August 15, 2008
Authority. While the RFP was open to all interested and qualified vendors, only those
technologies deemed qualified by the Authority were eligible for consideration.
The Authority was directed to obtain proposals for expanding the current WTE
capacity in two ways: (1) additional capacity at the current facility to meet Harford
County's needs, but not provide significant additional energy to the Aberdeen Proving
Ground (APG), and (2) build a new RRF to accommodate the waste disposal needs of
Hanford County, including capacity for some of the waste disposal needs of adjacent
"Base Realignment and Closure Act" (BRAG) affected counties (Baltimore and Cecil
Counties), and provide a greater amount of the energy needs of APG. APG had
agreed to lease an additional 20 acres of land next to the existing RRF for the larger
regional facility.
The Authority has short- listed both Covanta Energy and Wheelabrator Technologies
proposals as responsive and will continue the procurement process with those firms.
The Authority is currently seeking approval from Harford County to begin formal
negotiations with the vendors to arrive at a final contract to be voted on by the
Harford County Council. Best and final offers have been requested from both
companies and should be received by the end of September 2008, followed by final
selection and negotiations.
4.2.3 City of Sacramento, CA
In August 2007, the City of Sacramento, CA issued an RFQ soliciting an experienced
and qualified firm to partner with it to process MSW utilizing alternative technologies
premised on resource recovery and /or energy creation. To qualify, firms must have
had demonstrated experience and capacity to finance, design, build, own and
operate a facility that processed MSW in excess of what the City currently disposes
of, approximately 2,300 TPD after diversion. Sacramento was interested in a facility
that used treatment technologies including, but not limited to, pyrolysis, gasification,
advanced thermal recycling (a second generation advancement of mass -burn
technologies), biological, chemical, physical and /or a combination thereof. They
wanted technologies that were well proven at commercial scale, had high landfill
diversion rates, and could generate a wide range of useful by- products that could be
marketed for revenue sharing by the City and its development partner.
In October 2007, the City received 11 responses to the RFQ, not all of them waste
processing technologies. The City performed a technical evaluation of the responses
and went to the Council to request an Exclusive Negotiating Rights Agreement
(ENRA) with a single company, U.S. Science and Technology. A plasma arc
gasification project is being evaluated with due diligence expected to be completed in
early September. City officials traveled to Japan to visit a plant that employs a
similar technology at a commercial level (Westinghouse Plasma Corporation). A
decision on the implementation of the project is expected in the near term.
4.2.4 Broward County, FL
The Broward County Solid Waste Disposal District (District) in July 2007 was
considering changes to its solid waste management infrastructure in the near term.
Because its disposal contracts with two privately -owned WTE facilities will reach the
end of their initial service agreement terms in the near future, the District recognized
that many options to be considered would require significant development time, and
thus began the process to proactively evaluate such options. The District sought,
through a Request for Expressions of Interest (RFEI), to identify firms that could
GBB/C08027 -01 19 August 15, 2008
meet all or a portion of the District's future solid waste processing and disposal
requirements, and that were consistent with its long -term objectives. While this was
not a procurement, it was understood that information obtained during the process
would be used to support future procurement(s).
The expressions of interest were due by October 2007, and 25 vendors responded to
the REFI. To date The Broward County Solid Waste Disposal District, Resource
Recovery Board has received all the expressions of interests from the 25 respondents
as well as 11 presentations made to the Board by some of the respondents and no
further decisions have been made. Not all of the submittals were for WTE solutions.
Negotiations for a contract extension are taking place with Wheelabrator, and a
decision to move to forward is expected in 2008.
4.2.5 St. Lucie County, FL
On April 30, 2006, the Board of County Commissioners, St. Lucie County, Florida,
solicited offers for the purpose of obtaining services to permit, finance, construct,
operate, and own a Plasma Arc Gasification Facility to process MSW for St. Lucie
County. The due date for the qualifications was May 2006.
There was only one respondent to the RFQ issued by the County: Jacoby /Geoplasma.
As of November 2007, the development contract has been signed, and the County is
moving forward with the project. The developer plans to process 3,000 TPD,
generating 120 megawatts of electricity, one -third of which will be consumed
internally. According to the developers, the plant will cost over $425 million and
take two years to construct. Construction is slated to begin in 6 - 8 months pending
permits.
4.2.6 Hawaii County, HI
In 1995, the County started searching for a landfill replacement. After searching for
more than a decade and spending about $1 million, it selected Wheelabrator
Technologies Inc., a wholly -owned subsidiary of Houston -based Waste Management
Inc. Wheelabrator emerged from a field of three finalists, including Covanta, which
runs HPower on Oahu, and L -Con Contractors, a partnership with Barlow Projects,
Inc. In January 2008, the County received a best - and -final offer from Wheelabrator.
In May, the County Council voted against the 650 TPD project because of the
estimated $12.5 million cost, leaving the County with no plan for dealing with Hilo -
area trash after 2012.
4.2.7 Pinellas County, FL
Pinellas County had three companies bid on the contract to operate the existing WTE
plant. The process began with an RFQ to pre - qualify firms. The three firms that were
pre - qualified all submitted bids. Those respondents were Wheelabrator, Covanta and
Veolia. The bid went out in September 2006 for an operator replacement for an
existing 2,000 ton per day plant and was awarded to Veolia in January 2007. Veolia
actually began operating the facility effective May 7, 2007.
4.2.8 Hillsborough and Lee Counties, FL
Two operating mass -burn waterwall facilities in Florida began expansions in 2007. In
Lee County, the 1200 TPD plant will add a third line with a 636 TPD capacity, using
the same Covanta technology as the two operating lines, at a cost of $123.2 million
GBB/C08027 -01 20 August 15, 2008
or $194,000 per ton of installed capacity. Hillsborough County sole- sourced to
Covanta a new 600 TPD line to add to the two operating 600 TPD lines already in
place. The cost to Hillsborough County for the new line will be $123 million or
$205,000 per installed ton of capacity. The project is expected to be completed, tested
and accepted by the County in July 2009.
4.2.9 Fairbanks North Star Borough, AK
The Fairbanks North Star Borough (FNSB) is soliciting proposals for optimizing the
management of the MSW stream. The FNSB is seeking a long -term partnership to
implement a method for economical disposal of the community's MSW while
returning energy savings to the Borough - with an emphasis on waste reduction,
recycling and WTE options. Proposals were due May 29, 2008.
The following dates represented the FNSB's best estimate of the schedule being
followed to select the successful proposer for this project.
Proposal Evaluations
June 1 - July 31, 2008
Notice of Intent to Award (NOIA) Issued
August 2008
Contract Negotiations
August/September 2008
Assembly Approval of Contract Award
September /October 2008
Contract Execution
November 2008
After the Notice of Intent to Award has been issued, the Borough and the successful
offeror shall conduct good faith negotiations to address all aspects of a resulting
contract. Should the Borough be unable to negotiate a contract with the successful
offeror, negotiations will be formally terminated. The Borough may then initiate
negotiations with the second highest ranked offeror. This process may continue until
an agreement is reached.
4.2.10 City of Tallahassee, FL
The City of Tallahassee, FL, a Public Power Community, in November 2006 issued a
letter of interest to seven project developers requesting a two -page summary for
consideration of their technology for development of a renewable energy facility
serving the City of Tallahassee's service territory within Leon County, FL. The City
received three written responses, all from developers using biomass as fuel for
conventional steam generation. Two additional companies made formal
presentations to City representatives for advanced gasification projects, one project
utilizing MSW and the other utilizing woody biomass as fuel sources. In January
2007, the City began direct negotiations with one of the companies that made the
formal presentations, Green Power Systems based in Jacksonville, Florida. In June
of 2007, the City approved the contract for Green Power Systems to begin
development of a 1,000 TPD plasma gasification plant generating 35 MW net. The
purchase power agreement for the sale of electricity to the City of Tallahassee was
signed in June 2007. To date, Green Power Systems is conducting geo- technical
work on site suitability as well as design and engineering work based on site
suitability. Financing has been secured for the development of the plant, and it is
scheduled to begin operation in October 2010.
GBB/C08027 -01 21 August 15, 2008
4.3 Comparison of Technologies Chosen in Recent
Research/ Procurements
In the foregoing studies, reports and procurements, a total of 78 technology vendors
were represented, evaluated, screened or selected in some way for consideration as
waste processing solutions for the local entities. These 78 vendors offered 14
different technologies. The listing of the 78 vendors is presented in Table A -1 in
Appendix A of this paper. Several of those technologies /vendors were mentioned
more than once. Table 4 -1 lists the 14 that were cited three or more times in the
various documents.
The most often cited technology was mass burn, represented by Covanta and
Wheelabrator, who have the most commercial experience of any of the vendors
listed. Second on the list is gasification firm IWT, which employs the Thermoselect
technology in use in Europe and Japan. Other gasification technology providers are
also mentioned, along with four anaerobic digestion vendors, one plasma arc firm
two pyrolysis providers and a thermal depolymerization firm. While this review is not
systematic, it does provide a good summary of the firms and technologies that are
most active in the field, and those that localities across the U.S have been most
interested in using as they contemplate alternatives to landfilling MSW.
Table 4 -1. Technologies /Vendors Mentioned in Recent Procurements
Vendor - designated
Technology
Vendor
Total
Times
Cited
Mass Burn
Covanta Energy Corporation
7
Gasification
InterCity Waste Technologies/Thermoselect
I
6
Mass Burn
Wheelabrator Technologies Inc.
5
Anaerobic Digestion
Valorga S.A.S. (Valorga) /Waste Recovery
S stems
4
Anaerobic Digestion
Waste Recovery Seattle Inc. WRSI
4
Anaerobic Digestion
Arrow Ecology and Engineering
3
Anaerobic Digestion
Urbaser
3
Gasification
Ebara
3
Gasification
Taylor Recyclinq Facility
3
Gasification
Whitten Group /Entech Renewable Energy
S stem
3
Plasma Gasification
Global Energy Solutions
3
Pyrolysis
Pan American Resources
3
Pyrolysis
International Environmental Solutions
3
Thermal De of merization
Changing World Technologies
3
GBB /C08027 -01 22 August 15, 2008
5.0 Opinion on Economic Feasibility, Effectiveness,
and Environmental Issues of Waste Processing
Technologies
5.1 Economic Feasibility of Waste Processing Technologies
The economic characteristics of the waste processing technologies, including capital
and operating costs and risk, are summarized in Table A -2 in Appendix A. Generally,
capital cost for the proven technologies are in the range of $150,000 to $250,000
per ton of installed capacity, depending on size and plant configuration. Operating
costs are in the range of $35 to $60 per ton processed, not including residue
disposal, again dependent on size, equipment and operating profile, and assuming a
private operator. These figures are based on industry rules -of- thumb, recent
operating results from selected facilities, surveys of industry professionals and
related references.
A significant factor in the net operating costs for these facilities is revenue from the
sale of recovered energy and recyclables. The energy revenue is a function of
negotiations between the facility operator and the energy markets, typically a utility,
and may include, besides a power rate, revenue for capacity and a requirement for
standby power. Capital equipment necessary for utility connections can also be part
of the negotiations, and the actual figures have to be developed and refined for
specific sites and requirements during a procurement/development and negotiation
process.
5.1.1 Typical Waste Processing Technologies Project Economic
Estimates
To provide the County with an idea of the project economics that it could expect
from adopting a WTE strategy for the future management of its MSW that is not
reduced /reused /recycled, a representative preliminary project pro forma Operating
Statement was prepared. By deriving an order -of- magnitude cost per ton for the
processing and disposal of MSW using a waste processing technology, the County
can compare the cost of developing new landfill capacity or other means of disposal
after the existing landfill is filled to capacity.
The technology chosen for modeling was mass burn /waterwall incineration, the
technology with the most extensive track record at the size and scale needed to
serve the County. The nominal size of the facility selected is 300 TPD, making it one
of the smallest WTE plants in the United States. (There are two mass -burn facilities
in that size range - Commerce, CA and Wallingford, CT.) This assumes that Orange
County would be able to partner with an adjacent community.
The procurement method assumed for the analysis was a design - build- operate
public - private partnership, with public ownership and financing through 100 percent
tax - exempt revenue bonds. This structure is the one recommended by numerous
solid waste financing professionals and experienced facility owners throughout the
U.S. This method gives the County the benefit of single- source private involvement
in the construction and long -term operation of the facility, while retaining the
advantages of public ownership. Such advantages include:
GBB /C08027 -01 23 August 15, 2008
1. Lower overall financing costs. Tax - exempt debt is generally less costly than
private debt -equity structures, even if the private debt portion of the
financing is through tax - exempt private activity bonds.
2. More waste flow control. Public owners have a greater ability to control waste
flow to their facilities based on the recent Oneida - Herkimer Supreme Court
decision (See reference in Section 4.0).
3. Post - financing control. After the expiration of the initial financing, usually 20-
30 years, the County would still be the owner of the plant, reaping the benefit
of lower disposal costs without debt service payments, and not subject to
market pricing by a private owner - operator. Several existing plants,
especially in New England, are now reaching the end of their initial service
agreements and financings, and the communities they are serving that still
need disposal services are facing higher tipping fees or loss of guaranteed
available capacity.
Of course, the actual procurement method should be the result of an open
procurement process with several alternatives open to proposers to suggest as they
deem them advantageous to the County.
5.1.2 Assumptions
The following are the assumptions used for the pro forma Operating Statement:
1. Size/Throughput. As stated above, the representative plant is 300 TPD
processing a total of 87,600 tons per year, which equals an availability of
about 80 percent. The remainder of the annual waste generated would need
to be transferred and landfilled; a cost of $50.00 per ton has been assumed
for bypass.
2. Ash Generation /Disposal. Using a rule of thumb, 25 percent of the annually
processed waste (21,900 tons) would remain as ash after the thermal
recovery process. The ash can be disposed at a landfill at $50.00 per ton but
may have to be disposed separately from the bypassed waste in an ash
monofill. If found to be hazardous, ash would need to be separately disposed
of as a hazardous waste. The cost of such ash management would be in the
range of $150 to $250 per ton, including transportation and disposal at a
specially designed and operated landfill. If a beneficial use, such as
alternative daily landfill cover, was found, the cost could be reduced.
3. Capital Cost/Financing. The capital cost per ton is set at $150,000 per ton of
installed capacity or a total of $45 million. The effective net amount to be
financed was estimated at 125 percent of the cost of the installed capacity,
taking into account development and permitting costs, financing costs, etc.
That brings the total financed to $56.25 million. The all -in cost of financing
using revenue bonds was estimated at 5 percent for 25 years, an annual
financing factor of 0.0651, bringing net annual debt service to $3.99 million.
4. Electricity Revenues. The net amount of electricity generated from the
system, excluding in -plant use was set at 350 kilowatt-hours per ton
processed. The assumed price of the electricity sold was $0.06 per kilowatt-
hour, which is typical of what many plants receive for their electrical sales.
Any electrical agreement and its associated price would have to be negotiated
with the utility. It was also assumed that the plant operator would receive 10
percent of the electricity sales as an incentive payment, with 90 percent going
to the County.
GBB/C08027 -01 24 August 15, 2008
5. Materials Revenues. Ferrous metals can be recovered from the bottom ash
and sold as scrap on the open market. It was assumed that 2 percent of the
incoming waste or 1,752 tons per year would be recovered and sold at a
current price of $80.00 per ton. It was assumed that the plant operator
would receive 50 percent of the sales as an incentive payment, a standard
industry practice.
6. Operating Costs. A cost of $57.00 per ton processed was assumed for the
analysis.
5.1.3 Pro Forma Operating Statement
Based on the assumptions above, the annual Operating Statement of the system
would be as presented in Table 5 -1.
Table 5 -1. Pro Forma Annual Operating Statement
Revenues
Costs
Electricity $1,839,600
Ferrous Recovery $140,160
Total Revenues $1,979,760
Operating & Maintenance
Ash Disposal
ByPass Disposal
Annual Debt Service
Operator Revenue Sharing
Total Costs
$4,993,200
$1,095,000
$660,000
$3,991,076
$183,960
$10,923,236
Net Cost $8,943,476
Net Cost /Ton $102.09
The ash produced by the facility would need to be transferred and landfilled. The
estimated cost for this is projected at $50 per ton in Table 5 -1.
The cost per ton is quite sensitive to the price of electricity. For example, if it could
be assumed that electricity could be sold for $0.09 per kilowatt-hour instead of $0.06
per kilowatt-hour, the net disposal cost of approximately $102 per ton would be
reduced to $89 per ton, an approximate 13 percent reduction in cost.
5.2 Effectiveness of Waste Processing Technologies
Since any WPT will have some residual in need of disposal, when discussing
effectiveness of a WPT, emphasis is placed on obtaining the least amount of residual
material for final disposal. While combustion technologies significantly reduce the
volume of material destined for landfills, the resulting ash must be managed. Typical
management methods include disposal in a Subtitle D landfill or beneficial use in
construction projects and alternative daily cover for landfill wastes. In Europe,
where land for landfilling is scarce and several countries have banned landfills, the
GBB/C08027 -01 25 August 15, 2008
ash is processed to recycle the ferrous and nonferrous metals and the remainder is
graded and used in road and other construction.
The biological processes produce residues as well. These are of two types: (1) inert
residues that are landfilled and (2) organic residues that can be cured to be a soil
amendment or compost. Biological WPT are mass reduction technologies so that
contaminants such as heavy metals are concentrated in the residue. Tests for these
contaminants need to be conducted during operations and appropriate measures
taken.
For all but the high- temperature thermal options and the anaerobic digestion system,
an ash will be generated. Bottom ash will be discharged from the bottom of the
furnace chamber, and fly ash will be collected by the air pollution control system. In
accordance with applicable law, WTE ash must be tested to ensure it is non-
hazardous. The test is called the Toxicity Characteristic Leaching Procedure (TCLP).
Generally, the bottom ash has not been classified as a hazardous material, subject to
ash testing and analysis. Fly ash, however, will have a higher concentration of heavy
metals and may also contain residual organics. As such, it would likely be classified
as a hazardous material if it fails toxicity testing, unless it is combined with bottom
ash, as is the current U.S. practice.
It should be noted that communities with aggressive, comprehensive recycling
programs and programs focused on removing toxics from the MSW stream, such as
those to divert used electronics (e- waste), household hazardous waste (HHW),
mercury thermometers, fluorescent light fixtures, batteries, various metals and white
goods, and the like, could be expected to have a post - diversion MSW stream for
combustion containing less toxic materials and thus the ash from combustion to have
a lower potential to exhibit hazardous characteristics upon TCLP testing.
The solids residual from high temperature systems, such as plasma -arc or pyrolysis,
may have a better opportunity for end -use applications and marketing. These
glassy -type granules may be classified as non - hazardous and used in construction
materials or as a fill.
Vendors claim the substrate after digestion is beneficially processed and recovered,
with the residue from anaerobic digestion is nothing more than stones, glass or
similar items, which is normally directed to a solid waste landfill. However,
digestion, like combustion, is a concentrating process. This is the result of the
organic matter being converted to gas and utilized or released into the atmosphere.
As a result toxic materials in the waste will be part of the residue but in a higher
concentration than in the original feedstock. These claims are unproven in plants
operating using MSW as feedstock.
5.3 Environmental Issues of Waste Processing Technologies
5.3.1 Air Quality
5.3.1.1 Applicable Regulations
Solid waste incinerators, which the U.S. EPA refers to as Municipal Waste
Combustors, are regulated under the federal Clean Air Act, originally passed by
Congress in 1963 and updated in 1967, 1970, 1977,1990 and 1995 and 1998.
Numerous city and local governments have enacted similar legislation, either
GBB/C08027 -01 26 August 15, 2008
implementing federal programs or filling in locally important gaps in federal
programs.
Section 111 of the federal Clean Air Act directs the U.S. EPA to establish pollution
control requirements for certain industrial activities which emit significant "criteria air
pollutants." These requirements are known as new source performance standards
(NSPS) and regulate pollutants. For thermal destruction of solid waste, the NSPS
control particulate matter (PM), sulfur dioxide(S02), carbon monoxide (CO), nitrogen
oxides (NO,), hydrogen chloride (HCI), dioxins /furans, cadmium, lead, mercury,
fugitive ash and opacity. NSPS are detailed in Chapter 40 of the Code of Federal
Regulations, Part 60 (40 CFR Part 60), and are intended primarily to establish
minimum nationwide requirements for new facilities.
Section 112 of the pre -1990 federal Clean Air Act directed the U.S. EPA to establish
standards to reduce emissions of hazardous air pollutants (HAPs). These pollutants
include asbestos, benzene, beryllium, inorganic arsenic, mercury, radionuclides, and
vinyl chloride. National emission standards for hazardous air pollutants (NESHAPs)
are detailed in 40 CFR Part 61 and establish minimum nationwide requirements for
existing and new facilities.
The post -1990 NESHAPs require the maximum achievable control technology (MACT)
for a particular industrial source category, and are often referred to as "MACT
standards." The pre -1990 Clean Air Act prescribed a risk -based chemical -by- chemical
approach. The 1990 Clean Air Act Amendments outlined a new approach with two
main components. The first component involves establishing technology -based
source category standards, and the second component involves addressing any
significant remaining risk after the national standards are in place. The NESHAPs
promulgated under the 1990 Clean Air Act Amendments can be found in 40 CFR Part
63 and establish nationwide requirements for existing and new facilities.
The U.S. EPA may implement and enforce the requirements, or the U.S. EPA may
delegate such authority to state or local regulatory agencies. Clean Air Act Section
111 and 112 emissions limits applicable to new Municipal Waste Combustors are:
Dioxin /furan (CDD /CDF)
13 nanograms per dry standard cubic meter
Cadmium (Cd)
10 micrograms per dry standard cubic meter
Lead (Pb)
140 micrograms per dry standard cubic meter
Mercury (Hg)
50 micrograms per dry standard cubic meter
Particulate Matter (PM)
20 milligrams per dry standard cubic meter
Hydrogen chloride (HCl)
25 PPM or 95 percent reduction
Sulfur dioxide (SOZ)
30 ppm or 80 percent reduction
Nitrogen Oxides (NO,)
180 ppm dry volume, and 150 ppm dry volume after
first year of operation
A new source review (NSR) permit is required for a new municipal waste combustor
and, in addition, depending on its size and emission quantities, it must meet the
prevention of significant deterioration (PSD) permit requirements.
5.3.1.2 Air Quality Impacts
In the early 1980s, dioxins were discovered in the exhaust of a WTE facility on Long
Island, NY. This chemical, toxic to animals in even very small quantities, was
considered a major pollutant. Other WTE plants were tested, as well as other
GBB/C08027 -01 27 August 15, 2008
industries, and were found to be a major dioxin source. In 1995, amendments to
the Clean Air Act (CAA) were enacted to control the emissions of dioxins, as well as
other toxins, such as mercury, hydrogen chloride and particulate matter.
With the implementation of the CAA requirements in the following years, dioxin
emissions from WTE decreased significantly, as shown in Figure 5 -1.14 The U.S. EPA
has stated that "Waste -to- Energy is no longer a major contributor of dioxin
emissions."
Figure 5 -1. Dioxin Emissions from WTE Facilities, 1990 — 2005
4.500
p, 4,000
`ea
M 3,500
N
m 3,000
CS
~ 2,500
N
e 2,000
111 1,500
W
e 1,000
G 500
0
1990 1993 1996 1999 2000 2005
Year
Mercury is another toxin that was found in WTE exhaust and that was addressed in
the CAA amendments. By modifications in the burning process and the use of
activated carbon injection in the air pollution control system, dioxins and mercury, as
well as hydrocarbons and other constituents, have effectively been removed from the
gas stream. Mercury emissions from WTE have been reduced from 1990 levels, as
shown in Figure 5 -2.15
Figure 5 -2. Mercury Emission from WTE Facilities, 1990 - 2005
50.0
D.-
CL
40.0
.s
A 30.0
W
20.0
a
10.0
1
51.2
30.5
16.9
WIN
1990 1993 1996 1999 2000 2005
Year
14 Emissions from Large MWC Units at MACT Compliance, Docket A -90 -45 (Large MWCs), U.S.
EPA, Research Triangle Park, NC.
is Ibid.
GBB /C08027 -01 28 1 August 15, 2008
5.3.2 Water
Mass -burn and RDF incineration technologies and any WTE that produces steam will
require a water supply, and all types of projects have a wastewater discharge.
Water is required for the boilers, and domestic water for workers is also needed.
Non - potable water may be used as cooling water for the steam condensers, but the
large cooling water supplies necessary for condenser cooling are normally not
available, and cooling towers or cooling water ponds are provided as part of the
facility. Air - cooled condensers are an option, but they increase capital costs and
reduce net power production.
If the energy is going to a steam customer, the water requirement may be increased
significantly from that needed for electricity generation, assuming that the customer
generally does not return condensate. Some projects may cogenerate steam and
electricity for sale, such as district heating /cooling projects or those with a significant
steam user in proximity of the WTE facility site.
Technologies such as gasification and anaerobic digestion will not necessarily use a
boiler. They may generate a gas stream for use off -site and not require a condenser
cooling water system. They may utilize the gas to power a turbine or piston engine.
These approaches are not inherent water users; however, gasification systems may
require water in the gas cleanup and processing. Each system would need individual
evaluation.
Biologic systems, including ethanol production and anaerobic digestion, are wet
processes. The question to be examined is how much water is required and how
much is recycled. The answers to these questions will be system - specific. For
example, Arrow -Bio, which uses a water -based system, claims that no water is
required for the process other than that in the waste, which is recycled.
GBB/C08027 -01 29 August 15, 2008
6.0 Opinion on Which Waste Processing Technologies
Should Be Considered for Orange County
Of the waste processing technologies examined, only WTE is a proven technology
which could be recommended for implementation consideration by Orange County at
this point in time. As mentioned earlier, there are 89 WTE plants generating power
in the U.S. and hundreds worldwide. The other technologies discussed are in various
stages of development.
The alternative technologies are not mature enough to mitigate the risks potentially
inherent with their implementation:
Risk of technical failure - The technology is unproven.
Risk of pricing uncertainty - Should the County enter into a purchasing
agreement with a vendor for a WPT, the ultimate price paid may be much
higher than that indicated in the proposal.
Risk of environmental non - compliance - The technology's environmental
performance may be insufficient to meet regulations.
In evaluating waste processing technologies for Orange County to consider, it is
apparent that there is not enough waste generated by the County to gain the
economies of scale necessary to make a waste processing technology a cost - effective
investment. The estimated cost to process a ton of waste at a WTE facility in Orange
County is $102. To improve the economics of utilizing waste processing technology,
Orange County would need to partner with an adjacent community. The $102 per ton
is not competitive with the County's current landfill disposal fee of $49, nor with
Waste Industries' cost of $42 per ton to transfer and dispose of waste. Although
currently unknown, the cost of the County's new transfer station and landfilling at a
remote site is unlikely to reach $100 per ton. As the County investigates the cost of
transfer and disposal in preparation of its landfill closing, WPT may be more
economically attractive once the cost of transfer and disposal is known.
If $102 per ton were to look competitive, it is recommended that Orange County
conduct a WTE plant feasibility study which considers both mass -burn and modular
technologies, and /or fuel production approaches.
GBB/C08027 -01 30 August 15, 2008
Appendix A
Table A -1. Firms Evaluated by Recent Waste Processing Studies or Procurements
Table A -2. Summary of Municipal Waste Processing Technologies
GBB/C08027 -01 August 15, 2008
Table A -1. Firms Evaluated by Recent Waste Processing Studies or Procurements
Technology Jurisdiction
tS� 0g,�c1'���e
ty" G C?� �.og �� 4`- Z� Cif y'�• Q•tP` 40�
Vendors
Advanced Thermal Recycling Global Environmental Technologies X 1
Advanced Thermal Recycling Consutech Systems LLC X 1
Advanced Thermal Recycling Basic Envirotech Inc. X 1
Aerobic composting Wright Environmental Management Inc. (Wright) X X 2
Aerobic cDmposting composting American Sio-Tech X 1
jDn ic com stir Horstmann R i ethnic GmbH X 1
ic Digestion Mini ants X 1
ic Digestion Real Earth Technologies X 1
ic Digestion American Bic-Tech X 1
ic Digestion HotRW Ltd or ken Industries X 1
ic Digestion International Bio Recovery Corporation IBR X 1
bic ' estion /row Eool and En ineerin X X X 3
bic D' es tion Canada Com sti X X 2
bic estion Kame/DePlano X 1
bic Di estion New bio X 1
bic Di estion X 1
bic Di estion anic Waste stems X X 2
bic Di estion VAGRON X 1
bic estion Valorga S.A.S. ab asts Recovery Systems X X X X 4
Anaerobic digestion Canada Composting, Inc. (CCI) X 1
Anaerobic digestion Organic Waste Systems N.V. (OWS) X 1
Anaerobic digestion ISKA GmbH X 1
Anaerobic digestion Arrow Ecology Ltd. X 1
Anaerobic digestion Citec X 1
Anaerobic digestion Global Renewablas/ISKA X X 2
Anaerobic cation Waste Recove Seattle Inc. RSI X X X X 4
Anaerobic Digestion Urbaser X X X 3
Composling Zenker X 1
Composting RRI - Switzerland X 1
Gasification BRI Energy X X 2
Gasification Dynecology X 1
Gasification Ebara X X X 3
Gasification Ecosystem Projects X 1
Gasification Emerald PowerAsebella City X 1
Gasification GEM America X 1
Gasification ILS Partners/Pyromex X 1
Gasification Interstate Waste Technol iesRhenmoselect I X X X X X X 6
Gasification Jov Theodore Somesfalean X 1
Gasification Kame/DePlano X 1
Gasification Taylor Recycling Facility X X X 3
Gasification The epics X 1
Gasification Primen RRA X X 2
Gasification Omnifuel /Downstream Systems Omni X 1
Gasification Whitten Group /Entech Renewable Energy System X X X 3
Gasification Energy Products of Idaho (EPI) X 1
Gasification Bri htstar Environmental X 1
Gasification Omnifuel Technologies, Inc. X 1
Gasification Green Energy Corp X 1
Gasification Envirepell X 1
Gasification - Zia Metallurgical Processes, Inc. X 1
Hydrolysis Arkenal Fuels X 1
Hydrolysis Biofins - X 1
Hydrolysis Masada Oxynol X 1
Mass Bum Covanta Energy Corporation X X X X X X X 7
Mass Bum Wheelabrator Technologies Inc. X X X X X 5
Mass Bum Veolia Environmental Services X 1
Mass Bum Seghers Koppel Technology, Inc. hers X X 2
Other Thermal (Microwave) Molecular Waste Technd ies, Inc. X 1
Plasma Gasification Global Energy Solutions X X X 3
Plasma Gasification GSB Technologies X 1
Plasma Gasification Peat Inrtemational/Menlo Int X 1
Plasma Gasification Rigel Resource Recovery and Conversion Company X X 2
Plasma Gasification Solana Group X 1
Plasma Gasification Startach Environmental X 1
Plasma Gasification Geoplasma LLC X X 2
Plasma Gasification Plasma Environmental Technologies, Ina X 1
Plasma Gasification Plasco Ene Group X 1
Plasma Gasification USST X 1
Pyrolysis Entro 'c Technologies Corporation X 1
arolysis Pan American Resources X X X 3
Pyroysis WasteGen Ltd. /1-echTrade asteGen X X 2
Pyrolysis Conrad Industries X 1
Pyrolysis Graveson Energy Management X 1
Pyrolysis International Environments! Solution X X X 3
Steam Classification BLT/Worid Waste Technologies X 1
Thermal Da manzefion Changing World Technologies X X X 3
Thermal Oxidation Zeros Technology Holding X 1
Footnote:
GBB/C08027 -01 A -1 August 15, 2008
Table A -2. Summary of Municipal Waste Processing Technologies
* Does not Include risks related to procurement, such as vendor quality and deep - pockets (ability to provide technical, construction and operating guarantees; underwrite risks, etc.)
GBB /C08027 -01 A -2 August 15, 2008
Technology
Environmental Issues
Economic
Issues
Applicability to RI
RI Risk
operations/
Alternative
Description
Experience Record
Size Appli ublll
Reliability
Capital
Maintenance
Risks Llabill *
Summary
Unprocessed MSW fired In a
The predominant method of
Modules up to 750 •
High proven
Air emissions (controlled
S200k to $262k per
$35 to $50 /ton
Proven commercial
chamber built of water tubes.
WTE in the US and overseas
TPD, with total facility
reliability, over 90%
by statute). Requires
Installed ton (high)
(moderate) O &M
technology at
Mau-
Burn /Waterwall
Heat recovered for steam and /or
for decades. Over 60 plants
size over 3,000 TPD
residual disposal.
costs. Minimal
appropriate scale.
Very Low
electricity production
currently in commercial
materials recovery.
Requires new legislation.
operation
Unprocessed MSW fired in a
Substantial experience with
Modules up to 150
High proven
Air emissions (controlled
$146k to $183k per
$50 to ;60 /ton (high)
Proven commercial
series of refractory chambers
facilities firing MSW In Europe
TPD, with total facility
reliability, over 90%
by statute). Requires
Installed ton
0 &M costs. Minimal
technology; limitations
Mass-
Burn - Modular
followed by a heat recovery
and to a lesser extent In the
size up to 450 TPD
residual disposal.
(moderate)
materials recovery.
In scaling up to size
Low
Boller for steam and /or
U.S.
needed. Requires new
electricity productl on
legislation.
Shredded MSW, with ferrous
Dozens of facilities In
Modules up to 750
Good proven
Air emissions (controlled
$158k to $198k per
$50 to $55 /ton (high)
Proven commercial
metals removed, and fired In a
operation since the 1970's
TPD, with total facility
reliability, over 80%
by statute). Requires
Installed ton
0&M costs. Good
technology at
RDF/ Dedicated
chamber built of water tubes.
size over 3,000 TPD
residual disposal.
(moderate)
materials recovery
appropriate scale.
Low
Boller
Preprocessing can Increase
revenue potential.
Requires new legislation.
materials recovery.
Shredded MSW fired In a sand
One facility firing MSW in the
Facility size up to 460
Good proven
Air emissions (controlled
High capital cost
High O &M costs. Good
Proven technology;
bed. Preprocessing can Increase
US, other units In Europe and
TPD
reliability, over 80%
by statute). Requires
materials recovery
limited U.S commercial
RDF /Fluid Bed
materials recovery.
Japan
residual disposal.
revenue potential.
experience; scalabiilty
Moderate
an Issue. Requires new
legislation.
Heated MSW In oxygen - starved
One pilot plant In California
Pilot plant sized for 50
Insufficient
Air emissions (controlled
High capital cost
High O &M costs
High risk, uncertain
environment produces a fuel gas
operating for 2 years
TPD MSW
experience to
by statute), Odors from
commercial potential.
Pyrolysis
that Is Incinerated to generate
establish reliability
MSW transport. Residue
No operating experience
High
usable energy - steam and /or
estimate
may have beneficial use,
with large scale
electricity
operations. May require
new legislation.
Heated MSW In oxygen- starved
Two facilities firing MSW in
Multiple modules of
Insufficient
Limited air emissions
High capital cost
High O &M costs
Limited operating
environment generates a fuel
Japan since 1998, 10 small
300 TPD MSW each
experience to
(controlled by statute),
(one vendor
experience at only small
Gasification
gas that can be exported for
units firing MSW In Europe
establish reliability
potential air emissions
estimates $235k-
scale. Subject to scale-
High
heat or power generation
and Asia
estimate
when gas Is fired. Residue
$250Winstalled ton)
up Issues.
may have beneficial use.
Extensively
One facility in operation In
Operating facilities up
Insufficient
Odor, potential air
Low capital cost
High 0 &M costs.
Limited operating
preprocessed /Shredded MSW
Israel for less than two years;
to 300 TPD
experience to
emissions when gas Is
Several materials
experience at small
Anaerobic
directed to a series of digesters
other limited facilities In
establish reliability
fired. Residue may have
revenue streams may
scale. Subject to scale-
High
Digestion
for gas generation that can be
Europe
estimate
beneficial use.
be available,
up Issues.
exported for heat or power
eneration
MSW heated by a plasma -arc In
Two pilot plants In operation
Less than 200 TPD
Insufficient
Air emissions (controlled
Very high capital
Very high 0 &M costs
No commercial
oxygen -starved environment
since 1999 In Japan
MSW
experience to
by statute). Residue may
cost
experience to date.
produces a fuel gas that is
establish reliability
have beneficial use.
Subject to scale -up
Plasma Arc
Incinerated to generate usable
estimate
Issues. May require new
High
energy for steam and /or
legislation.
electricity. Similar to
gasification.
* Does not Include risks related to procurement, such as vendor quality and deep - pockets (ability to provide technical, construction and operating guarantees; underwrite risks, etc.)
GBB /C08027 -01 A -2 August 15, 2008
Appendix B
Overview of Waste Processing Technologies (WPT)
GBB/C08027 -01 August 15, 2008
Appendix B
Overview of Waste Processing Technologies (WPT)
1.1 "Proven" Technologies
Waste has been converted to beneficial use on a large scale for well over 100 years.
Incineration with electric power generation was first applied to MSW in 1894 in New
York City. Since that time, the burning of MSW with energy recovery (now known as
WTE) has matured into a safe, effective and environmentally acceptable technology.
The proven large -scale waste processing methods include incineration and starved -
air combustion, as defined below:
Mass -burn Incineration: This is the controlled combustion of organic or inorganic
waste with more than the ideal air (stoichiometric) requirement - excess air - to
assure that complete burning occurs.
Starved Air Combustion: Starved air incineration utilizes less air than conventional
incineration, and it produces ash similar in appearance to that from a conventional
incineration process. The gases that result are burned in a second chamber. The
lower air requirement leads to smaller equipment sizes. This process, however, is an
incineration process.
Refuse - derived Fuel (RDF): An RDF system processes waste by shredding it and
removing ferrous metals in preparation for combustion. The removal of non -
combustibles can increase the specific heat content by over 10 percent and can allow
for revenues from the metals removed.
It has been found that recycling, the most preferred waste management option aside
from waste reduction, increases when WTE exists in the United States as well as in
other countries. As shown in BioCyc %'s °2006 State of Garbage in America,"
(http: / /www.jgpress.com /archives /_free /000848.htm1), most of the states with large
energy recovery rates have recycling rates higher than the national recycling
average of 28.5 percent.' These recycling rates range from 43 percent in Minnesota
(where 21 percent of the waste is burned for energy) to 24 percent in Connecticut
(where 65 percent of the waste is burned for energy). North Carolina illustrates the
inverse with 19 percent recycling and .9 percent combustion for energy.
Apparently, where WTE exists, there is greater public awareness of waste disposal
and the need to deal with waste reduction overall.
Other methods of MSW disposal, such as mixed -waste composting and landfilling,
are being used but they are becoming less and less attractive. Mixed -waste
composting requires large land areas, creates significant odor, and produces compost
that is limited in its application because of contaminants. Landfilling is not a
processing technology, it is storage. It also requires large land areas or a large
capital investment, generates methane (a greenhouse gas that is more than 20
times as potent as carbon dioxide, which is generated from WTE), and creates other
' BioCyc% includes recycling, composting, yard waste, WTE and landfill collection in its figures.
EPA reports MSW from a slightly different source. They include collection receipts for domestic
waste and for industrial waste, but their recycling quantities are derived from firms that
recycle the waste, such as paper mills or steel plants, rather than from collection data. This
difference in methodology from that used by Biocyc% is reflected in the difference in recycling
rates in the United States in 2006, which is reported as 32.5% by EPA and 28.5% by Bioycie.
GBB /C08027 -01 B -1 August 15, 2008
environmental impacts, like uncontrolled discharge of leachate that may pollute
groundwater sources.
WTE has proven to be a reliable method for waste processing and disposal. Modern
plants are compatible with aggressive recycling programs and have an
environmentally acceptable track record.
While new WTE procurements have declined in the United States, the market for this
equipment has increased in Europe and in Eastern Asia. European and Japanese
systems suppliers actively market their systems and are consistently improving their
performance. The technology is well tested and is used more than any other for WPT
facilities in the United States and overseas. Table B -1 illustrates the use of WTE
technology throughout the world.
Table B -1. WTE Facilities Worldwide
Location
Number of
Amount of MSW Managed by WTE as a
Total
Facilities
% of Total MSW Generated
USA
89
12.5% based on MSW reported by U.S. EPA and
14
5
BioCycle's data
Europe
400
Varies from country to country
Japan
100
70 to 80%
Other nations (Taiwan,
Singapore, China, etc.)
70
Varies from country to country
Source: "The 2008 IWSA Directory of Waste -to- Energy Plants," Integrated Waste
Management Services Association website
Table B -2 illustrates the size and ownership of WTE facilities in operation in the
United States. Fifty-two percent of the facilities are owned by public entities,
Wheelabrator Technology (Waste Management Inc.) owns 13 percent, Covanta
Energy owns 21 percent, and other private firms own 13 percent. Private
companies own more of the larger facilities.
Table B -2. WTE Facilities in the United States
Size
(Ton Per Day)
Publicly
Owned
Privately
Owned
Total
:5100
7
0
7
101 -499
14
5
19
500 -999
8
17
25
1,000 -1,999
11
9
20
>_ 2,000
6
12
18
Total
46
43
89
Table B -3 shows the various technologies used in U.S. plants with the majority of
plants utilizing mass burn technology.
GBB/C08027 -01 B -2 August 15, 2008
Table B -3. U.S. WTE Plants by Technology
Technology
Operating
Plants
Daily Design
Capacity (TPD)
Annual Capacity 1
(Million Tons)
Mass Burn
65
71,354
22.1
Modular
9
1,342
0.4
RDF- Processing &
Combustion
10
15,428
4.8
RDF- Processing Only
5
6,075
1.9
RDF- Combustion Only
5
4,592
1.4
Total U.S. Plants 2
94
98,791
30.6
WTE Facilities
89
92,716
28.7
Annual Capacity equals daily tons per day (TPD) of design capacity multiplied by 365 (days /year)
multiplied by 85 percent. Eighty-five percent of the design capacity is a typical system guarantee of
annual facility throughput.
Z Total Plants includes RDF Processing facilities that do not generate power on site.
Source: J.V.L. Kiser and M. Zannes, Integrated Waste Management Services Association, April 2004.
In the region, 10 WTE facilities currently operate, processing almost 12,000 TPD of
MSW. Table B -4 describes those plants.
Table B -4. WTE Plants in Region
Location
Size
TPD
Start
Date
Energy Product
Owner /Operator
North Carolina
New Hanover County
500
1984
electricity'
New Hanover County
South Carolina
Charleston
600
1989
steam & electricity
AT &T /Montenay Charleston RRI
Virginia
Alexandria
975
1988
electricity
Covanta Arlington - Alexandria, Inc.
Fairfax County
3000
1990
electricity
Covanta Fairfax, Inc.
Hampton
240
1980
steam
NASA and City of Hampton /City of Hampton
Harrisonburg
200
1982
steam & electricity
City of Harrisonburg
Portsmouth
2000
1988
RDF & electricity
Southeastern Public Service Authority
(SPSA)
Maryland
Baltimore
2250
1985
electricity
John Hancock Life Insurance Company/
Wheelabrator Baltimore, L.P.
Harford County
360
1988
steam & electricity
Northeast Maryland Waste Disposal
Authority/Energy Recovery Operations, Inc.
Montgomery County
1800
1995
electricity
Northeast Maryland Waste Disposal
Authority/ Covanta Mont ome Inc.
' Originally built as a "steam" plant, the facility now generates and sells electricity .2
Source: Integrated Waste Management Services Association
The following sections describe the basic types of MSW combustion technologies, all
of which have been in use for decades in the U.S.
2 New Hanover County Government, Department of Environmental Management website.
GBB/C08027 -01 B -3 August 15, 2008
1.1.1 Mass - Burn /Waterwall Combustion
In mass -burn waterwall combustion, MSW is placed directly into the system for
incineration with no pre - processing except for removal of identifiable white goods
(refrigerators, washing machines, microwave ovens, etc.). Waste is placed onto a
grate at the bottom of a combustion chamber in a furnace with walls built of water
tubes, as shown in Figure B -1. Air for combustion is forced through the grates
(under -fire air) and through parts in the sides of the combustion chamber (over -fire
air).
Figure 13-1. Waterwall Furnace Section
Half the heat generated from the burning waste is absorbed by the waterwalls and
the balance heats water in the boiler, as shown Figure B -2.
3 Source: Babcock and Wilcox.
GBB /C08027 -01 B -4 August 15, 2008
S--DIY EM d
r>tt F zwe S,g healer
�eeAt (Lars ) i..wama strA
GmPP* C.-WO Cow steam
G_ Owvaaor Ch~ Elccraw emart>aer Feed ,� -�A-0- Lime
Ears Ta* Soo
. .. .Carbon 0aWm
.$AO Lime.
7
TWVFW
Carooft.e AomiAna Kain _ 1,4,.d Urtll
Refuse Hddp PA Ae Fro+ P7staon Teeadneb 5ow� de,1+. E.ar A..FM
.rx
Alum oob.�acs s.w'.m` ,a .wFd ' view
S � Aid E 1 MM ..... �`"mv1 !A T.*
Me4npa j ��
HldLLY YakerteL2dUCLC lU "i ^�y�
4m. Realse AEfAht K fldil�Q'A.1
Figure B -2. Typical Mass -Burn Waterwall System4
The off -gas exiting the boiler passes through an air pollution control system where
the majority of pollutants is removed and is discharged through a stack to the
atmosphere. Waste is burned out to an ash in the furnace. Heat extracted from the
waterwalls *and the boiler section generates steam which, in most facilities, is
directed to a turbine generator for electric power production. Waterwall systems are
fabricated on -site. They are generally applied to larger systems, 200 TPD up to 750
TPD, with multiple units used when higher capacity is required. They are forgiving in
their operation, and are reasonably efficient in the burnout of waste and in the
generation of energy.
1.1.2 Mass- Burn /Modular Combustion
Modular combustion is another incineration process. Unprocessed MSW is placed
directly into a refractory lined chamber. The primary chamber of the incinerator
includes a series of charging rams which push the burning waste from one level to
another until it burns out to an ash and is discharged to a wet ash pit, as in Figure B-
3. No or limited under -fire air is used to limit the entraining of ash into the flue
(exhaust) gas stream.
a Source: Fairfax County, VA.
GBB/C08027 -01 B -5 August 15, 2008
Figure B -3. Typical Modular Combustion System
Less than the ideal (stoichiometric) amount of combustion air is injected into the
primary combustion chamber, and a combustible gas is produced from the
incomplete waste combustion. The gas from the burning waste is directed to a
secondary combustion chamber where additional air is added to complete the
burning process. Hot gases pass though a separate waste heat boiler for steam
generation and then through an air pollution control system before discharge through
the stack to the atmosphere.
A major advantage of this system is injection of less air than ideal in the primary
combustion chamber. With less air, the fans can be smaller and the chamber itself
can be smaller than with other systems. Also, with less air flow, less particulate
matter (soot) enters the gas stream and the air pollution system can be sized for a
smaller load.
Modular systems are factory built and can be brought to a site and set up in a
relatively short period of time. They are less efficient than waterwall units in waste
burn -out and in energy generation. They have been built in unit sizes up to 150
TPD. Multiple units are used to increase plant size to 300 - 400 TPD, such as in
Agawam, MA.
1.1.3 Refuse - derived Fuel /Dedicated Boiler
RDF, in its simplest form, is shredded MSW with ferrous metals removed. Additional
processing, such as screening, can be applied to the incoming waste stream to
remove and recover glass, aluminum, and other non - combustible materials.
Additional processing stages may also be placed in the processing line, such as
5 Source: Consutech Systems, Richmond, VA.
GBB /C08027 -01 B -6 August 15, 2008
pelletizing. Pelletizing is the compression of "fluff" RDF into dense pellets generally
to be fired along with lump coal. The pellet size depends on the size of the coal used
in existing power plants.
RDF production is a distinct process; therefore, it is not necessary to be co- located
with the combustion plant. In Figure B -4, RDF is blown into the furnace from the
left, above the grate. What does not burn in suspension (above the grate) will burn
on the grate, and the hot gases generated will pass through a waterwall section and
then a boiler section. This system is similar to the mass -burn waterwall facility
except in the nature of waste charging and burnout.
STEW
MR O Y
L_.`_.._ ... ` ....
_.J
Figure B -4. Typical RDF Combustion Fac11111ty6
The unique feature of RDF systems is in the pre - processing of waste. As seen in the
diagram of a typical RDF processing facility in Figure B -5, MSW enters the facility and
then passes through a trommel, where bags of waste are broken open and large
material is removed. The small material dropping out of the first trommel passes
through a second trammel to remove fine noncombustible material. The majority of
waste goes through a shredder for size reduction. A magnetic separator removes
ferrous metals and the balance of the material is fired in the furnace.
6 Source: Energy Answers Corporation.
GBB/C08027 -01 B -7 August 15, 2008
Figure B -5. Typical RDF Processing Schematic'
Other configurations may include additional separating equipment or exclude
trommels, but the RDF generated is always shredded so that it is capable of being
blown into a furnace. Although results vary with the processing configuration, in
general, about 80 percent of the incoming waste stream is converted into RDF for
the thermal process.
An advantage of this system is in the removal of metals and other materials from the
waste stream. While not all these facilities include this step in the processing line,
those that do can realize revenue from the sale of recovered metal. For instance, at
the North County Resource Recovery Project in West Palm Beach, Florida, the
nominal 3,000 TPD facility removed and sold over 30,000 tons of ferrous metals in
2003, which represented over 3 percent of the weight of the incoming waste stream.
With the removal of non - combustibles, the specific heat content of the RDF can be
increased by 10 percent over the original MSW.
1.1.4 Refuse - derived Fuel /Fluidized Bed
In this incineration process, MSW is shredded to less than four inches mean particle
size (the same as with the RDF process described in 1.3.1 above) to produce the fuel
(see Figure B -5) before it is blown into a bed of sand in a vertical cylindrical furnace.
Hot air is also injected into the bed from below, and the sand has the appearance of
a bubbling fluid as the hot air agitates the sand particles. Moisture in the RDF is
evaporated almost instantaneously upon entering the bed, and organics burn out
both within the bed and in the freeboard, the volume above the bed. Steam tubes
are embedded within the bed, and a transverse section of boiler tubes captures heat
from the flue gas exiting the furnace, as shown in Figure B -6.
7 Source: generic.
GBB/C08027 -01 B -8 August 15, 2008
Sua«nd
Fud Steam
ro Fan OW Re mwW and scononlim BaBt — ID Fan Stack
cleaning system
Figure B -6. Typical RDF Fluid Bed System8
Fluid bed incineration is more efficient than grate burning -based incineration
systems. The bed is very effective in waste destruction and requires less air flow
than mass -burn or modular systems. The fluid bed, however, does require relatively
uniform -sized material, and RDF preparation is necessary for system operation, not
for resource recovery, as discussed above.
1.2 "Emerging" Technologies
There are many technologies currently being proposed for the treatment and
disposal of MSW throughout the world. Most of these involve thermal processing,
but some others comprise the biological or chemical decomposition of the organic
fraction of the waste to produce useful products like compost or energy products,
notably synthetic gas (syngas) for downstream combustion.
Thermal processing refers to a number of different types of technologies utilizing
heat as the mode of waste treatment. However, most of them, as listed and
described below, are variations of conventional incineration.
Gasification: Heating of an organic waste to produce a burnable gas (approximately
85 percent hydrogen and carbon monoxide mix) for use off -site. As long as the off -
gas produced from the system is usable and burned off -site, the system is a gasifier,
not an incinerator. Typically, the energy in MSW is both used to fire the system and
contained in the gas product.
E!yrolysis: A form of gasification where organic waste is heated without air. A gas is
generated that is burned in the gaseous phase, requiring much less oxygen than
conventional incineration. This process also generates a char, or frit, depending on
the process temperature. (Frit is a glassy, granular material that is uniform in
appearance.) The presence of a secondary combustion chamber for the burnout of
the pyrolysis gas requires that this system be classified as an incinerator.
Plasma arc: Plasma arc refers to the means of introducing heat into the process.
Essentially a plasma arc system is a pyrolysis or starved air process generating heat
by firing the waste with a plasma arc to produce a syngas, which is then combusted
to produce steam and /or electricity, and is classified as an incinerator. If the system
8 Source: Energy Products of Idaho, Coeur D'Alene, ID.
GBB/C08027 -01 B -9 August 15, 2008
generates an off -gas that contains burnable gases (e.g., hydrogen and carbon
monoxide) that can be used off -site, it can be classified as a gasifier.
1.2.1 Gasification
Gasification is the heating of an organic waste (MSW) to produce a burnable gas
(approximately 85 percent hydrogen and carbon monoxide mix) for use off -site.
While pyrolysis systems are primarily focused on waste destruction, a gasifier is
designed primarily to produce a usable gas. As shown in Figure B -7, Thermoselect, a
European firm represented in the U.S. by InterCity Waste Technologies of Malvern,
PA, has developed a system composed of 400 TPD modules processing MSW.
Figure B -7. Typical Gasification System9
Waste is fed into a gasification chamber to begin the heating process, after being
compressed to remove entrapped air. Some oxygen; sufficient only to maintain the
heat necessary for the process to proceed, is injected into the reactor where
temperatures in excess of 3,000 °F are generated. At this high temperature, organic
materials in the MSW will dissociate into hydrogen, methane, carbon dioxide, water
vapor, etc., and non - organics will melt and form a glass -like slag. After the gas is
cleaned, water is removed, and the gas can be used for power generation, heating,
or other purposes. The glass -like slag can be used as fill, or as a building material
for roads, etc.
A variation of the fluid bed incineration system described in this section is the
fluidized -bed gasifier, shown in Figure B -8.
9 Source: International Waste Technologies, Malvern, PA.
GBB /C08027 -01 B -10 August 15, 2008
IM
G
Ecowmim Air ]UgFiltm
P
1,300-1,4001C IWW Preheater
6 0.011C ade h& ba. L-14- L—r LJ
Figure B -8. RDF Fluidized Bed Gasification Systemlo
Although this system is described as gasification technology, it does not export a
burnable gas. RDF is first prepared using a process similar to the ones illustrated in
Figures B -4 and B -5. The RDF (called "wastes" in Figures B -7 and B -8) is then
charged to the fluid bed and the gas generated is directed to a secondary
combustion chamber, shown above, with molten slag dropping out to a water - cooled
sump. The molten slag solidifies into a glass -like material which can be used as a
construction material or fill. Heat from the gas fired in the combustion chamber is
captured in hot water tubes to generate steam which can be used for electric power
generation. Without the generation of a usable gas stream and with the necessity of
a combustion chamber for gas burn -out, this system is an incinerator.
A gasifier marketed for MSW is built by EnTech of Devon, England, as shown in the
schematic in Figure B -9. This is a complex system which generates recyclable
metals, plastics and other potential revenue streams, in addition to a salable gas
(syngas). EnTech provides case studies of nine small -scale facilities in operation. A
67 TPD facility operates on a mixture of MSW.
io Source: Ebara Corporation, Tokyo.
GBB/C08027 -01 B -11 August 15, 2008
Figure 13-9. EnTech Process Schematic"
As shown in Figure B -9, MSW is classified by a combination bag breaker and gravity
separator process, termed a Kinetic Streamer. Oversize materials, which are
basically inorganic, are directed either to a plastics recycler or a non - plastics
recycling station, while the majority of waste (presumably organic) is directed to a
dryer to remove entrained moisture. The dryer utilizes the latent heat inherent in
the organic content of the waste to produce the heat necessary to drive the
gasification process. The syngas can be fired in a waste heat boiler for steam and
subsequent electric power production.
1.2.2 Pyrolysis
In pyrolysis, an organic waste (MSW) is heated without oxygen (or air), similar to
the generation of coke from coal or charcoal from wood. Both a char and a gas are
generated. The gas is burned out in a gaseous phase, requiring much less oxygen
than incineration. The char will usually melt at the temperatures within the pyrolysis
chamber and will be discharged along with a black gravel -like substance, termed frit.
Advantages of this process are in the lack of air entering the chamber and the
resulting smaller size of system components. Without air, there is little nitrogen
oxide generation and low particulate (soot) formation. There have been many
attempts to develop this technology outside a laboratory or a pilot plant. In full -
scale demonstrations in the 1970s, it was difficult to maintain a sealed chamber to
keep air out, and waste variability creates problems in maintaining consistent
operation. When the pyrolysis gas is fired in a combustion chamber that is part of
the system, the system is classified as an incinerator.
As shown in Figure B -10, MSW is shred into a uniform size capable of feeding into
the thermal converter, or pyrolysis chamber. The pyrolysis gas generated is fired in
a secondary combustion chamber, or thermal oxidizer, and passes through a waste
heat boiler for heat recovery. Char drops out the bottom of the pyrolysis chamber
for disposal or further processing for recovery of metals and other constituents.
Although this system is marketed as a pyrolysis system, a combustion chamber is
necessary for its operation (for destroying organics in the off -gas) and the presence
of this chamber classifies the system as an incinerator.
" Source: Entech.
GBB /C08027 -01 B -12 August 15, 2008
a�
V
0
Water
o d
D ried
Organic
organic
a
Materials &
Materials &
MSW
Wastec
Residues
Residues
Entech Syngas
Kinetic
Dryer
Gasifier
Streamer
d
d d
�
Solid
Residue
d
d
� a
�
d �
Figure 13-9. EnTech Process Schematic"
As shown in Figure B -9, MSW is classified by a combination bag breaker and gravity
separator process, termed a Kinetic Streamer. Oversize materials, which are
basically inorganic, are directed either to a plastics recycler or a non - plastics
recycling station, while the majority of waste (presumably organic) is directed to a
dryer to remove entrained moisture. The dryer utilizes the latent heat inherent in
the organic content of the waste to produce the heat necessary to drive the
gasification process. The syngas can be fired in a waste heat boiler for steam and
subsequent electric power production.
1.2.2 Pyrolysis
In pyrolysis, an organic waste (MSW) is heated without oxygen (or air), similar to
the generation of coke from coal or charcoal from wood. Both a char and a gas are
generated. The gas is burned out in a gaseous phase, requiring much less oxygen
than incineration. The char will usually melt at the temperatures within the pyrolysis
chamber and will be discharged along with a black gravel -like substance, termed frit.
Advantages of this process are in the lack of air entering the chamber and the
resulting smaller size of system components. Without air, there is little nitrogen
oxide generation and low particulate (soot) formation. There have been many
attempts to develop this technology outside a laboratory or a pilot plant. In full -
scale demonstrations in the 1970s, it was difficult to maintain a sealed chamber to
keep air out, and waste variability creates problems in maintaining consistent
operation. When the pyrolysis gas is fired in a combustion chamber that is part of
the system, the system is classified as an incinerator.
As shown in Figure B -10, MSW is shred into a uniform size capable of feeding into
the thermal converter, or pyrolysis chamber. The pyrolysis gas generated is fired in
a secondary combustion chamber, or thermal oxidizer, and passes through a waste
heat boiler for heat recovery. Char drops out the bottom of the pyrolysis chamber
for disposal or further processing for recovery of metals and other constituents.
Although this system is marketed as a pyrolysis system, a combustion chamber is
necessary for its operation (for destroying organics in the off -gas) and the presence
of this chamber classifies the system as an incinerator.
" Source: Entech.
GBB /C08027 -01 B -12 August 15, 2008
Figure B -10. Process Diagram of a Pyrolysis System 12
1.2.3 Plasma Arc
Plasma arc technology is a gasification system that uses the intense heat generated
by a plasma torch to drive the process. Net energy generation is not established
based on Japanese and European experience. It is a pyrolysis - related process where
little or no oxygen is injected into a reactor. A typical unit is shown in Figure B -11.
Electric current is passed through a series of torches at the bottom of a reactor,
which heat a process gas (not shown) to a temperature in excess of 5,000 °F. This
hot gas stream heats waste within the reactor to over 3,500 °F and, as air is provided
to the system at a low controlled rate, some of the waste will burn to help maintain
reactor temperature. At this high temperature, organics within the waste will form
elemental compounds, such as hydrogen, oxygen and carbon, with some of this
carbon converting to carbon monoxide or methane. The gas flow will have a high
enough heat content to be able to sustain its own combustion and be used as a fuel
gas external to the system.
The inorganic portion of the waste will form a liquid slag which eventually drops from
the reactor into a water bath. As soon as it hits the water it will shatter into a
glassy - looking residue or frit that may be suitable for fill or use as a construction
material.
12 Source: Integrated Energy Systems, Inc., Romoland, CA.
GBB/C08027 -01 B -13 August 15, 2008
SYNGAS OJT
MSW IN
PLASMA HEATING SYSTEM PLASMA HEATING SYSTEM
SLAG AND METAL OUTLET CM LGNESTDNE BED
Figure B -11. Cross - Section of a Plasma Arc Furnace 13
1.3 Biological Fuel Production
Producing a "fuel" product from organic materials in waste by biological processes is
termed biological fuel production. Typically, this fuel product takes the shape of
combustible gas or liquid formed when organic material in waste breaks down.
Decomposition of the organic portion of waste by microorganisms in the absence of
oxygen, known as "anaerobic digesting," creates methane (CH4) and other gases in
combination with about half the energy of natural gas. This biogas can be used as a
fuel and burned for energy or power production directly. It can also be refined to
produce a pipeline - quality gas that is almost pure methane and further processed
into a liquid fuel like methanol.
1.3.1 Cellulosic Ethanol
Ethyl alcohol, ethanol, is a biofuel that is usually produced from sugar or starch but
can be produced from wood, ,grasses, or other cellulose containing material,
including the organic portion of solid waste. This is referred to as cellulosic ethanol.
It is chemically identical to ethanol from other sources, such as corn starch or sugar,
but has the advantage that the feedstock is lignocellulose raw material that is highly
abundant and diverse. (The word "cellulosic' simply refers to the source material.)
However, it differs in that it requires a greater amount of processing to make the
sugar monomers available to the microorganisms that are typically used to produce
ethanol by fermentation.
13 Geoplasma, Atlanta, GA.
GBB/C08027 -01 B -14 August 15, 2008
GASIFICATION ZONE
MELTING ZONE .
CONTROLLED
CONTROLLED
AM
AIR
Y
PLASMA HEATING SYSTEM PLASMA HEATING SYSTEM
SLAG AND METAL OUTLET CM LGNESTDNE BED
Figure B -11. Cross - Section of a Plasma Arc Furnace 13
1.3 Biological Fuel Production
Producing a "fuel" product from organic materials in waste by biological processes is
termed biological fuel production. Typically, this fuel product takes the shape of
combustible gas or liquid formed when organic material in waste breaks down.
Decomposition of the organic portion of waste by microorganisms in the absence of
oxygen, known as "anaerobic digesting," creates methane (CH4) and other gases in
combination with about half the energy of natural gas. This biogas can be used as a
fuel and burned for energy or power production directly. It can also be refined to
produce a pipeline - quality gas that is almost pure methane and further processed
into a liquid fuel like methanol.
1.3.1 Cellulosic Ethanol
Ethyl alcohol, ethanol, is a biofuel that is usually produced from sugar or starch but
can be produced from wood, ,grasses, or other cellulose containing material,
including the organic portion of solid waste. This is referred to as cellulosic ethanol.
It is chemically identical to ethanol from other sources, such as corn starch or sugar,
but has the advantage that the feedstock is lignocellulose raw material that is highly
abundant and diverse. (The word "cellulosic' simply refers to the source material.)
However, it differs in that it requires a greater amount of processing to make the
sugar monomers available to the microorganisms that are typically used to produce
ethanol by fermentation.
13 Geoplasma, Atlanta, GA.
GBB/C08027 -01 B -14 August 15, 2008
According to U.S. Department of Energy studies conducted by the Argonne
Laboratories of the University of Chicago, one of the benefits of cellulosic ethanol is
that it reduces greenhouse gas emissions (GHG) by 85 percent over reformulated
gasoline. By contrast, ethanol from corn, which most frequently uses natural gas to
provide energy for the process, may not reduce GHG emissions at all depending on
how the starch -based feedstock is produced.
There are five steps to produce ethanol using a biological approach:
1. A "pretreatment" phase to make the lignocellulosic material, such as wood,
straw or solid waste, amenable to hydrolysis, and to remove as many
contaminants as possible;
2. Cellulose hydrolysis (cellulolysis) to break down the molecules into sugars;
3. Separation of the sugar solution from the residual materials, notably lignin;
4. Microbial fermentation of the sugar solution;
5. Distillation to produce 99.5 percent pure alcohol.
The process is shown graphically in Figure B -12; however, steps 2, 3 and 4 are
shown in one stage or process. Abengoa accomplishes these steps in a single
reactor.
1. Pretreatment
The first stage is physical processing of the feedstock: size reduction and removal of
contaminants. This is similar to the production of RDF. This is especially important
with solid waste where the fermentable portion may only be 60 to 70 percent of the
feed. Once the MSW is physically prepared cellulose, its susceptibility to
fermentation is still curtailed by its rigid structure. As the result, an effective
additional treatment is needed to liberate the cellulose from the lignin seal and its
crystalline structure so as to render it accessible for a subsequent hydrolysis step. A
number of pretreatment approaches have been developed to liberate the cellulose
and increase its reactability. To date, the available pretreatment techniques include
acid hydrolysis, steam explosion, ammonia fiber expansion, alkaline wet oxidation
and ozone pretreatment. Besides effective cellulose liberation, an ideal pretreatment
has to minimize the formation of degradation products because of their inhibitory
effects on subsequent hydrolysis and fermentation processes.
GBB/C08027 -01 B -15 August 15, 2008
Figure B -12. Process Flow of the BCyL Biomass Ethanol Plant 14
2. Hydrolysis
The cellulose molecules are composed of long chains of sugar molecules. In order to
break the cellulose down into sugars, the hydrolysis process is employed. There are
two major cellulose hydrolysis processes:
a) Acid hydrolysis - dilute acid may be used under high heat and high pressure,
or more concentrated acid can be used at lower temperatures and pressure. A
decrystalized cellulosic mixture of acid and sugars reacts in the presence of
water to complete individual sugar molecules (hydrolysis).
b) Enzymatic hydrolysis - uses several enzymes at various stages of this
conversion and has the advantage that lignocellulosic materials can be
hydrolyzed with relatively mild processing conditions, which avoids the
formation of byproducts that would otherwise inhibit enzyme activity.
These have been utilized singly or in combination to break the cellulose chains into
free sugar, which is fermented for alcohol production.
is Source: Abengoa Bioenergy
GBB/C08027 -01 B -16 August 15, 2008
3. Sugar Separation
Approximately half of the energy value in the cellulosic feedstock is captured in the
sugars produced in hydrolysis. Fermentation will be more efficient if this is
separated from other compounds, especially lignin. This can be accomplished with
membranes. The lignin also contains about half of the energy and can be used as an
energy source for the process.
4. Fermentation
Once the cellulose has been broken into sugars, microorganisms are used to ferment
the sugar and produce ethanol. Traditionally, baker's yeast has long been used in
the brewing industry to produce ethanol from hexoses (6- carbon sugar). When
lignocellulosic biomass is hydrolyzed to produce sugars, several sugars are produced
including xylose and arabinose (5- carbon sugars). As a result, specially engineered
microorganisms, mainly yeasts, have been developed and utilized in fuel ethanol
production from cellulose.
5. Distillation
The liquid resulting from fermentation is separated from any solids and heated to
volatize the ethyl alcohol which is then condensed. The process is repeated to
increase the ethanol concentration. An adsorption technique may be used to remove
the remaining water to produce anhydrous ethanol.
Because of the concern about using food crops to produce fuels and the potential
cost savings, a large number of companies have developed cellulosic ethanol
technologies, including:
• Abengoa Bioenergy
• Alico
• BlueFire Ethanol
• China Resources Alcohol Corporation (CRAG)
• Dyadic International, Inc.
• GreenField Ethanol
• Gulf Coast Energy
• Iogen Corporation
• Mascoma
• POET Biorefinery
• Range Fuels
• SunOpta Inc.
• Verenium Corporation
• Xethanol
1.3.2 Biogas
Roger Haug defines composting as "the biological decomposition and stabilization of
organic substrates, under conditions that allow development of thermophilic
temperatures as a result of biologically produced heat, to produce a final product
that is stable, free of pathogens and plant seeds, and can be beneficially applied to
land." 15 Composting of MSW or a portion of MSW such as yard waste is usually
carried out in the presence of air (aerobically) to produce a soil amendment and to
reduce the amount of MSW being deposited in landfills. When composting is done in
the absence of air (anaerobically), the biogas produced contains a significant amount
15 Roger T. Haug, The Practical Handbook of Compost Engineering, Lewis Publishers, 1993.
GBB/C08027 -01 B -17 August 15, 2008
of methane, about 50 percent. To capture this biogas the process must be in a
closed vessel.
When anaerobic digestion is applied to the organic fraction of MSW, the primary
purpose of the facility shifts from landfill diversion to biogas production. There are
many anaerobic digestion plants both in use today and historically that have been
installed to produce and utilize biogas as well as manage a waste. However, most of
these facilities utilize sewage sludge, animal manures and other homogenous wastes
as feedstock. Very few utilize MSW as a feedstock.
It has long been common practice in Europe to use anaerobic digestion at waste
water treatment plants to treat sewage sludge. It has been less common over the
same period to use anaerobic digestion to treat industrial effluents and agricultural
sludges, although there are a number of examples dating back to the 1950s. In the
last ten years or so in Europe, because of the introduction of a requirement that the
separated organic fraction of MSW be treated before landfill disposal, anaerobic
digestion has been adopted for this purpose. Anaerobic digestion has long been
popular in India where a large number of small and simple plants are in use
processing farm wastes. Currently, a number of vendors are offering farm -based
systems in both Europe and the United States.
The process of producing biogas from MSW by anaerobic digestion has similar steps
to the production of liquid biofuel discussed above. The process includes:
1. A "pretreatment" phase to make the organic material more available for
digestion by size reduction and to remove recyclable materials and
contaminates;
2. Digestion of the organic material in a closed vessel by microorganisms;
3. Treatment of the biogas to remove water, compress the gas, and other
processes depending on the end use; and
4. Curing of the solid residue from the digestion to produce a compost product
which may be marketable.
The longest established anaerobic treatment processes include:
• Anaerobic suspended growth,
• Upflow and down -flow anaerobic attached growth,
• Fluidized -bed attached growth,
• Upflow anaerobic sludge blanket (uasb),
• Covered anaerobic lagoons,
• Membrane separation anaerobic processes, and
• Dry process anaerobic digestion of MSW.
The above emerge in process designs, when developed and offered by the
technology providers, which are either optimized to:
1. Efficiently remove material (mostly organic) from liquid streams to permit
discharge of a treated effluent to a specified water quality standard, and
biogas production may be just incidental; or
2. To provide treatment of a waste material, including MSW, to make it suitable
for diversion away from landfill, with biogas generation optimized for revenue
creation, and potential sales of fibrous and liquid fertilizer by- products.
GBB/C08027 -01 B -18 August 15, 2008
Table B -5 provides a list of vendors that are offering anaerobic digestion systems in
Europe and elsewhere. The table categorizes the technologies offered by moisture
level, process temperature ( mesophilic low temperature and thermophilic high
temperature) and number of stages of the process. The U.S. EPA recently published
an industry directory for firms offering equipment and services in this technology. 16
Table B -5. International Anaerobic Digestion and Biogas Vendors
16 Industry Directory for On -Farm Biogas Recovery Systems, U.S. EPA, March 2008.
GBB/C08027 -01 B -19 August 15, 2008
Anaerobic Digestion
T wet
Technology Provider Single -Stage
wet
Single -Stage
Dry
Single -Stage
Dry
Single -Stage
wet
Multi -Stage
wet
Multi -Stage
Mesophilic
Thermophilic
Mesophilic
Thermophilic
Mesophilic
Thermophilic
ArrowBio
V
Biogen TBD
CAM BI
CiTEC TBD
'Dranco
N/
N/
Eco Technology JVV Oy', TBD
Entec Biogas GMBH N/
N/
GRL
Farmatic AG TBD
Grontmij
;Haase
Hese
HiRAD TBD
ISKA
Kompogas TBD
:Kruger ASBioTherm TBD
?Linde
OWS (Dranco)
Passavant
Paques TBD
Portagester
RosRoca N/
SBI
Schmack Biogas AG TBD
Schwarting (Uhde)
Valorga
V
.Wehrle
Mechanical- Biological- Treatment: A Guide for Decision Makers - Processes, Policies and Markets, Juniper
Consultancy Services, 2005
16 Industry Directory for On -Farm Biogas Recovery Systems, U.S. EPA, March 2008.
GBB/C08027 -01 B -19 August 15, 2008
1.3.3 Anaerobic Digestion
As applied to the processing of MSW, anaerobic digestion is a wet treatment process
where waste is first pre -sorted and then fed into water tanks. Using agitators,
pumps, conveyors and other materials handling equipment, MSW is wetted and
dissolved. Metals, glass and other constituents of MSW that have no affinity for
water are eventually discharged from the system into dedicated containers for
recycling, further processing or final disposal. The paper, garbage, soluble
components, etc., generate "black water" which has a relatively high organic
content. This stream is taken to a series of digesters where the time it sits in the
chamber, the residence time, will be sufficient to generate an off -gas. The process is
shown in the schematic in Figure B -13.
Figure B -13. Process Flow for Anaerobic Digestion Systems?
This gas is rich in methane and other organics and can be burned as a fuel for
heating or for electric power generation. The solid residual from the digestion
process is similar to compost and can be used as a soil amendment. The process
also separates out recyclable materials such as glass and metals. There are many
such facilities processing sewage sludge, manure and other homogeneous wastes.
ArrowBio of Haifa, Israel, is an example of a vendor that is offering to construct
anaerobic digestion facilities to process MSW in the United States. They have
responded to procurements in Los Angeles and New York. They operate a 300 TPD
full -scale MSW demonstration process line in Tel Aviv, illustrated in Figure B -14.17
The system operates without high temperatures or pressure. In theory, it is
extremely simple, relying on non - specialized mechanical equipment (pumps,
screens, macerators, tanks, conveyors, etc.) for operation. Digestion occurs through
the presence of natural microorganisms in MSW, so charging with specialty or unique
bacteria is not necessary. It has a high resistance to upsets because of the scale of
its operation, i.e., 300 tons of MSW entering the system per day, and any poisons
that might threaten the digestion process (as has been experienced with sewage
treatment plant digesters) are likely to be of such small fraction that it will have no
significant effect on digester cultures.
The system is equipment and labor intensive. Although redundancy is normally built
into the system, with multiple process lines and duplication of critical pumps,
17 Source: ArrowBio, Haifa, Israel.
GBB/C08027 -01 B -20 August 15, 2008
conveyors, etc., additional equipment adds to the number of separate process and
associated equipment necessary for operation. The Tel Aviv installation of Arrow has
thus far experienced many shut -downs due to the presence of troublesome
components in the input waste stream. To combat this, a higher level of pre-
processing is being implemented so that future applications can operate more
reliably.
Figure B -14. ArrowBio Facility in Haifa
GBB/C08027 -01 B -21 August 15, 2008