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Innovations for Existing Plants:
The AR&ET Program
Program Plan: FY 2000 - 2001FY
May 2000May 2000
Innovations for Existing Plants:
The AR&ET Program
Program Plan: FY 2000 - 2001FY
U.S. Department of EnergyOffice of Fossil Energy
National Energy Technology LaboratoryPittsburgh, Pennsylvania
Morgantown, West Virginia
A Message to Our StakeholdersThe availability of clean, affordable energy is essential for the prosperity and security of the UnitedStates and the world in the 21st century. In the United States today, over half the electricity comes fromcoal-fired boilers, and coal is projected to account for over half of U.S. electricity generation through2020 and beyond. Internationally, the amount of coal used in developing nations for electricity genera-tion is projected to more than double by 2020. Innovative emission-control technologies will berequired to alleviate, at low cost, the environmental concerns associated with coal combustion.
This document is the Program Plan for the Advanced Research & Environmental Technology (AR&ET)Program. In FY 2001, the program name will change to “Innovations for Existing Plants.” This namechange recognizes that there are 300 GW of air-combustion coal-fired electric generation assets in theUnited States, and there is a continuing need to improve their environmental performance. The namechange also recognizes that “existing” coal-fired power plant technology is and will continue to bedeployed in the developing world. As environmental awareness grows in these countries, retrofitemissions control technology will be needed for those systems as well.
The Program Plan describes the program drivers and goals, the R&D portfolio, program strategy, andprogram benefits. It is the direct result of collaborative work with our stakeholders. Key interactionsinclude:
• Collaborative cost-shared research on pollution control technologies to improve theirperformance and sharply reduce their cost.
• Collaborative work with the Tennessee Valley Authority, EPRI, and state and local environmentalagencies to evaluate the impact of fine particulates on visibility.
• Collaborative efforts with EPA, the Office of Management and Budget (OMB), EPRI, the utilityindustry, and independent research organizations on establishing the procedures under EPA’sInformation Collection Request (ICR) initiative for collecting data related to emissions of mercuryfrom coal-fired utility boiler systems.
• Partial sponsorship of NARSTO, a consortium of North American public and private organizationsthat are conducting research in support of air quality management, focusing on ozone andaerosols.
• A series of public meetings and one-on-one dialogues with key public and private sectorstakeholders involved in PM
2.5-related research and decision-making.
• Cosponsorship with the Office of Surface Mining, Department of Interior, of an interactive forumon coal combustion by-product (CCB) utilization.
• Ongoing efforts to provide technical analysis and high-quality data for use in policy andregulatory determinations.
Only with your involvement and support can we succeed. Achieving our goals will not be easy. Butwith a history of success—and a cooperative partnership with industry, academia, and government—we will have the best chance. We welcome your comments and suggestions about the plan. Pleaserespond directly to us or to the contacts listed on the back cover.
George Rudins Rita A. BajuraDeputy Assistant Secretary for DirectorCoal and Power Systems National Energy Technology Laboratory
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Innovations for Existing Plants:The AR&ET Program
Program Plan: FY 2000 - FY 2001
Table of Contents
List of Acronyms .................................................................................................................................... iii
Executive Summary ................................................................................................................................. iv
I. Introduction ......................................................................................................................................... 1
A. Program Drivers ........................................................................................................................... 1B. Federal Role ................................................................................................................................. 2C. Program Goals ............................................................................................................................. 2D. Program Relationships ................................................................................................................ 3
II. Program R&D Portfolio ....................................................................................................................... 4
A. Systems Analysis and Integration .............................................................................................. 5B. Mercury ....................................................................................................................................... 6C. Fine Particulate Matter (PM
2.5) .................................................................................................... 8
D. Coal Combustion By-products .................................................................................................. 12E. NO
x and SO
x.............................................................................................................................. 14
III. Program Management ...................................................................................................................... 16
A. Program Role and Strategy ........................................................................................................ 16B. Portfolio Approach to Management ......................................................................................... 16C. Stakeholder Outreach and Partnerships .................................................................................... 16D. Program Timing and Milestones ............................................................................................... 18E. Program Costs ........................................................................................................................... 18
IV. Program Benefits .............................................................................................................................. 19
A. Retrospective ............................................................................................................................ 19B. Future ........................................................................................................................................ 20
Appendix A: Key Regulatory Drivers ................................................................................................. A-1
ii
List of Acronyms
AR&ET Advanced Research and Environmental TechnologyBAU Business As UsualBBA Broad Based Agency AnnouncementBtu British Thermal UnitCAAA Clean Air Act AmendmentsCCB Coal Combustion By-productCO
2Carbon Dioxide
DOE United States Department of EnergyECBC Emission Control By-products ConsortiumEPRI Electric Power Research InstituteEPA Environmental Protection AgencyESP Electrostatic PrecipitatorFE Fossil EnergyFGD Flue Gas DesulfurizationHAP Hazardous Air PollutantHg MercuryIA Interagency AgreementICR Information Collection RequestNAAQS National Ambient Air Quality StandardsNETL National Energy Technology LaboratoryNO
xOxides of Nitrogen (NO, NO
2)
NSTC National Science and Technology CouncilOCDO Ohio Coal Development OfficeOMB Office of Management and BudgetPM Particulate MatterQ Quadrillion (1015)RCRA Resource Conservation and Recovery ActSO
2Sulfur Dioxide
SO3
Sulfur TrioxideSO
xOxides of Sulfur (SO
2, SO
3)
TRI Toxics Release Inventory
iii
Executive SummaryThe United States needs new technology toimprove the environmental performance of itscoal-fired electric generation assets. Similarly, asworld prosperity increases, other nations will seekto upgrade the environmental performance of theirenergy systems. Emissions control technologydeveloped by the AR&ET program will greatlyreduce the cost of this transition, providingsustained prosperity, energy diversity, and acleaner global environment.
The Technical and MarketChallenge
The coal power generation industry faces dualchallenges: new requirements from increasingenvironmental regulation and the cost-cuttingpressure of market deregulation.
Earlier pollution control systems for coal-firedpower plants have proven effective in reducingemissions by a factor of two or three at lowincremental cost. However, the clear trend inemissions regulations is removal of almost all(over 90%) of the species of concern to maintainthe ambient air quality and visibility standards setforth by the U.S. Environmental ProtectionAgency (EPA). Pollutant species contained influe gas—particulate matter, sulfur oxides (SO
x),
The World Tomorrow
The availability of affordable energy is, and willcontinue to be, essential to our nation’s economicstrength. Even with major advances in renewableenergy use, energy forecasts agree that coal andother fossil fuels will be the dominant energysource for the foreseeable future. By 2020, theUnited States will still rely on coal for over half itselectricity generation. Globally, developingcountries such as China and India will use theirabundant, domestic coal resources to fueleconomic growth; the amount of coal used forelectricity generation in the developing nations isprojected to more than double by 2020.
The economic need for sustained coal use mustbe balanced by improved technology to eliminatethe adverse impacts that emissions of certainchemical species can have on human health, theenvironment, and the global climate. Figure 1shows that pollutant emissions per unit of coalburned have decreased significantly in the UnitedStates over the past 30 years. However, over thesame period of time coal use has more thandoubled. With increased coal use, emissions perunit of coal must be reduced further to limitaggregate pollutant emissions.
Figure 1. Since 1970, the Environmental Performance of U.S.Coal-Fired Power Plants has Improved while Coal Use has Increased
iv
nitrogen oxides (NOx), acid gases, and mercury—
are present in dilute concentrations which greatlyincrease the technical challenge of near-completeremoval (see Figure 2).
The Program Opportunity
The AR&ET Program focuses on innovations thatwill enable the continued use of existing coal-firedelectricity generation assets, and the deploymentof new coal plants, including the advancedgeneration technologies being developed as apart of the Vision 21 program. The programopportunities are threefold:
• Developing comprehensiveenvironmental solutions that address all airemission and solid waste generation issues inan integrated manner
• Providing flexible systems that can be used witha wide range of plant configurations and sizes
• Providing technology solutions at or belowcurrent cost-of-electricity to ensure marketuse—in the United States and internationally.
R&D Portfolio
The program R&D portfolio has five primaryelements:
• Systems Analysis and Integration• Mercury• Fine Particulate Matter• Coal Combustion By-products• Nitrogen and Sulfur Oxides
These elements cover the entire “life cycle” ofemissions and technology, from source speciationthrough advanced emissions control technologydevelopment and testing. Data collected as“baseline” in control technology development canalso be used in policy and regulatory processes.
Program Role and Strategy
The AR&ET program has two major focuses:
• Developing advanced environmental controltechnology for coal-fired power plants, and
• Providing high-quality scientific data andanalysis for use in policy and regulatorydeterminations.
In conducting pollution control technology R&D,the program first seeks to obtain a fundamentalunderstanding of the chemistry of the pollutantspecies of concern as they exist in flue gas. Onthat basis, research into control technologies isinitiated. In addition to evaluating technologieson the basis of control performance and projectedcost, consideration is given to 1) the ease withwhich a control technology can be integrated intoboth new and existing electricity generationsystems, 2) the potential for the technology tocapture or control more than one pollutantspecies, and 3) balance of plant issues such asammonia slip, approach to saturation, etc. Theultimate goal is the development of fully inte-grated pollution control systems that address allof the environmental issues associated with coal-fired power generation in an optimal manner.
Figure 2. Pollutant Species are Contained in Flue Gas in Dilute Concentrationsand Near-Complete Removal is Difficult
v
The AR&ET Program is in a unique position toserve as an unbiased provider of high-qualityscientific data and analysis associated withemissions from coal-fired power plants and theperformance of various control technologies. Theprogram acquires such information as a part ofconducting control technology R&D. Also, theprogram works closely with industry in develop-ing control technology and has the contacts andrelationships required to garner the high qualitydata needed for effective policy and regulatorydeterminations.
Program Benefits
Program benefits include: (1) Development ofsound technical information on which appropriateregulatory decisions can be based; (2) Improve-ment of the performance and reliability of pollu-tion control technologies; and (3) Reductions inthe cost of such technologies. Because the firsttwo types of benefits are so difficult to quantify,calculated program benefits are based on loweringthe cost of environmental compliance for coal-fired electric generators. The aggregate cost ofenvironmental compliance for coal-fired genera-tors in the United States was 1.9 billion dollars in1997 and is projected to balloon to over 13 billiondollars per year by 2010 as more stringentenvironmental regulations come into effect. Oneprogram goal is to reduce the overall cost of
environmental compliance by 50%, throughadvanced technologies and integrated systems. Asuccessful program will provide savings of over6.5 billion dollars per year by 2010.
The program has a strong history of assisting inthe development of useful commercial products.Low-NO
x burners, advanced SO
2 scrubbers, and
other products have provided the United Stateswith both billions of dollars of savings and acleaner environment. Figure 3 shows that ascompetition in the electricity supply industry haslowered prices, generators have increased theiruse of coal. This trend is due, in part, to the R&Don advanced technologies conducted by theAR&ET Program. In collaboration with industry,the program seeks to continue R&D support tothe electricity generation industry, this will resultin:
• Continued consumer savings from the use ofthe most economic source of power—domesticcoal
• Continued improvement in ambient air quality• Technology solutions for large, emerging global
market applications to maintain U.S. leadershipin the export of electric-power generationtechnology and services
• Effective environmental technology that willenable the U.S. to maintain energy diversity in aderegulated electric supply industry.
vi
0
3
5
8
10
13
15
18
20
1970 1975 1980 1985 1990 1995 1997
Co
al
Us
e,
Qu
ad
rill
ion
Btu
pe
ry
ea
r
0
1
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3
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5
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9
10
Av
era
ge
Co
st
of
Ele
ctr
icit
y,
ce
nts
/kW
h
Quadrillion Btu cents/kWh
Coal use has continued to increase ascompetition in the electricity supply industryhas lowered the average price of electricity.
Figure 3. Coal Use and Electricity Cost in the United States
I. Introductionresulting heightened public awareness of emis-sions could lead to emissions limits more stringentthan those determined by regulators. Finally, thestatus of a number of coal-fired generationfacilities as grandfathered under the Clean Air Acthas recently been questioned by EPA on the basisthat certain repairs or replacements of equipmentperformed at those facilities. Figure 4 presents anhistorical overview of regulatory actions pertain-ing to coal-fired generation beginning with thepassage of the Air Quality Act in 1967. A moredetailed discussion of environmental drivers iscontained in Appendix A.
Concurrent to the increasing stringency ofemissions limits, the electric-generation industryis undergoing deregulation, prompting new effortsto maximize revenues and minimize operatingexpenses. Drivers for improving system perfor-mance for deregulated power markets include:
• Improving the efficiency of fossil-basedelectricity generation by lowering the parasiticload of environmental controls
• Reducing the operations and maintenance costsof environmental control systems
• Integrating power generation with otherproducts and revenue sources.
Utilization of CCBs will, for example, providepower generators with opportunities to generateadditional profits and decrease the waste disposalrequirements associated with coal combustion.However, the inherent variation in the physicaland chemical properties of CCB materials,combined with the high cost of transportation, willrequire site-specific applications development.
Against the backdrop of environmental regulationand the electric industry deregulation is the factthat coal-fired electric generation plants commis-sioned 20, 30, and even 40 years ago have turnedout to be highly reliable, low-maintenance, long-lived, and extremely low-cost sources of electric-ity. These plants are strong assets that havefueled the United States’ economic growth overthe past decades. However, they were notdesigned and built to meet current air qualityregulations, and new technologies are needed toimprove their environmental performance if theyare to continue to operate.
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This document presents the R&D plan for theAR&ET Program. It defines the role that theOffice of Fossil Energy (FE) will play to ensureenvironmentally sustainable power productionfrom fossil-based fuel systems in restructuredpower markets. The environmental issues ofconcern center around emissions of sulfur oxides(SO
x), nitrogen oxides (NO
x), particulate matter
(PM), hazardous air pollutants (HAPs), especiallymercury and acid gases, and the utilization andproper disposition of coal combustion by-products (CCBs).
This program plan is based on an ongoing seriesof collaborative efforts with stakeholders. Wewelcome our stakeholders’ comments and ideas.Please visit our web sites, or contact us via e-mailor telephone. (See the last page for details.)
A. Program Drivers
The program is driven primarily by environmentalregulations pertaining to coal-fired electricitygeneration, and the economic need for low-costcompliance options. Reductions in the allowableair emissions of sulfur dioxide, nitrous oxides,particulate matter, acid gases, and mercury arebeing implemented or planned based on a numberof issues including ambient air quality, acid rain,the health of aquatic ecosystems, and regionalvisibility in parks and other areas of interest.Also, the impacts of solid coal combustion by-products (CCBs) on groundwater are currentlybeing assessed and standards for some uses andmanagement practices may be developed in thefuture. Electric generators are now required toreport releases of hydrochloric acid sulfuric acid,mercury and other HAPs under the TRI. The
Vision Statement
The program vision is to develop to the pointof deployment advanced emissions controltechnologies for coal-fired power plants. Thesetechnologies will support the continuedproduction of low-cost, environmentally soundcoal-based electric power in the U.S. and helpmaintain U.S. leadership in the export of electricpower technology and equipment.
B. Federal Role
New technologies will be needed to meet theenvironmental challenges of coming years.However, the movement toward deregulation ofthe electricity supply industry has resulted in adramatic decrease in utility-based research,development, and demonstration of new technolo-gies. Risk-aversion in a highly competitive powermarket means less likelihood of investment inR&D for new technology. For these reasons,Federal government collaboration is essential toenable industry to develop the needed technol-ogy. By making retrofit and new-plant environ-mental compliance options available and lessexpensive than they would otherwise be, theDOE/industry partnership can make continuedoperation of existing coal assets a viable optionfor power generation companies.
Taking a longer view, federal government involve-ment in improving operations of the existing fleetof coal plants ensures that the coal infrastructurewill be intact when Vision 21 systems are ready forcommercial application–projected for the 2015 timeframe.
C. Program Goals
The overall goal of the AR&ET program is todevelop integrated, advanced environmentalcontrol technologies for achieving near-zeroemissions of SO
x, NO
x, particulates, and HAPs,
and to maximize the beneficial use of solid andliquid residual by-products from the use of fossilfuels. The program’s cost goal is to reduceenvironmental compliance costs for coal-firedpower plants by 50%, through both advancedtechnologies and integrated systems.
Figure 4. Environmental Regulation of Coal-Fired Electricity Generating Plants is BecomingIncreasingly Stringent
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Specific objectives include:
• Develop new technologies to meet existing andpotential regulations on mercury and otherhazardous air pollutants, particulate matter, acidgases, and nitrogen oxides by 2004-2005.
• Provide a better understanding of thecontribution of both primary and secondary fineparticulate emissions from coal-fired electric-utility boilers to ambient concentrations PM
2.5
by 2002-2004.• Demonstrate the acceptability of large-volume
uses of coal combustion by-products, such asin road construction and mine reclamation, by2000 with the ultimate goal of increasing theoverall utilization of solid coal combustion by-products from 30% to 50% by 2010.
D. Program Relationships
The AR&ET Program’s portfolio of activities isclosely linked to both the Vision 21 Program andthe Carbon Sequestration Program.
• The “Vision 21” concept is a new approach to21st century energy production from fossilfuels. It will integrate advanced concepts forhigh-efficiency power generation and pollutioncontrol into a new class of fuel-flexible facilitiescapable of co-producing electric power, processheat and high-value fuels and chemicals withvirtually no emissions of air pollutants. It will becapable of a variety of configurations to meetdiffering market needs, including bothdistributed and central power generation. Theintegrated pollution abatement systems beingdeveloped as a part of the AR&ET Program willbe compatible with Vision 21 concepts and mayenhance their commercial viability.
• The Carbon Sequestration Program isdeveloping systems for capturing greenhousegas emissions (especially CO
2) from fossil-fuel
production and utilization systems and otheranthropogenic emissions sources andsequestering the carbon either by converting itinto useful by-products or storing it inunderground formations or in the deep ocean.Parallel research will explore enhancing naturalcarbon sinks. Many of the options for
capturing CO2 from flue gas will also capture
SOx, NO
x, particulates, and HAPs. “One box”
concepts that would combine CO2 capture with
reduction of criteria pollutant emissions couldprovide highly cost-effective solutions.
• The AR&ET Program is focused onenvironmental controls for existing powerplants that convert coal to electricity via air-fedcombustion. Such power plants represent atremendous asset base for the United Statesboth in terms of generation capacity (300 GW)and associated infrastructure. Technologiesdeveloped for the U.S. systems will eventuallybe needed abroad, as environmental awarenessincreases in developing nations.
The AR&ET, Carbon Sequestration, and Vision 21Programs will combine synergistically to provide aportfolio of retrofit and new coal-fired electricitygeneration options that cost less, use less fuel,and emit near-zero levels of emissions into theatmosphere. The most recent program plans forthe Carbon Sequestration Program and the Vision21 Program can be downloaded from the DOEOffice of Fossil Energy website (http://www.fe.doe.gov/programs_coalpwr.html).
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II. Program R&D Portfolio
Figure 5. Program R&D Spectrum
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The overarching objective of this research anddevelopment effort is to achieve cost-effectivecoal combustion systems that have no adverseimpacts on human health and the environment.Within that objective, individual technologyefforts are aimed at either preventing the genera-tion of certain species in the combustion processor capturing them from gaseous effluents beforethey are emitted to the atmosphere. Species ofconcern include SO
2, NO
x, fine particulate matter,
mercury, and acid gases.
Another important concern is the management ofthe solid by-product materials (coal combustionby-products, CCBs) of systems that capturespecies from the gaseous effluents. Currently,70% of CCBs are disposed of in landfills; theprogram activities are aimed at finding moreproductive and environmentally benign uses forCCB materials. This activity is closely related tothe development of post-combustion treatmentsystems since different systems produce charac-teristically different solids, which affects manage-ment options.
A final element of the AR&ET Program, systemsanalysis and integration, involves examining theinterrelations of the various pollution controlsystem components, looking for opportunities tocombine functions and optimize and simplify theoverall system. The systems analysis andintegration element is crucial to achieving theprogram’s cost goal of reducing environmentalcompliance costs by 50% for coal-fired powergeneration systems that meet tighter environmen-tal requirements.
As shown in Figure 5, the AR&ET Programelements span the life-cycle of technologydevelopment, from the characterization of emis-sions through the deployment of integratedsystems. Some program elements are relativelymature, while others are in the earlier stages of thetechnology development cycle. The currentprogram portfolio has five main elements:
• System Analysis and Integration• Mercury and other HAPs• Fine Particulate Matter• Coal Combustion By-products• Nitrogen Oxides and Sulfur Oxides
Each is discussed in following sections.
GOAL:Identify and evaluate opportunities to combinecontrol of multiple pollutants in integratedsystems.
Compared to the predominantly single-pollutantcontrol approaches typical of most present-daysystems, integrated systems offer notablepotential benefits:
• Lower costs due to fewer components andsubsystems and reduced parasitic powerrequirements
• Smaller plant footprint, particularly important forretrofit applications.
Accordingly, systems analysis and integration willbe a key factor in achieving pollutant removal tovery low concentrations and at an acceptablecost.
Some of the technology control options shown inFigure 6, such as feedstock preparation, arealready covered by other parts of the FE program.Also, CO
2 sequestration is addressed in a
separate R&D program plan (the Carbon Seques-tration Program Plan). This systems analysisand integration program element is new and isintended to identify and evaluate the technologyopportunities for integrated systems across theR&D portfolio.
There are many different emissions controloptions along the coal utilization pathway, fromfeedstock preparation to combustion modificationto flue gas treatment (see Figure 6). The objectiveof systems analysis and integration is to examinethe interrelations among the various options,looking for ways to combine functions and createa simplified and optimized overall system. Indoing this, it is important to take a long-term viewand anticipate regulation of mercury, particulatematter, and CO
2 emissions, and also to focus on
the existing assets and how they can be bestutilized. Examples of integration options include:
• Evaluating the effect of SCR catalysts onmercury oxidation and subsequent capture in anESP, baghouse or scrubber.
• Improving the efficiency of wet scrubbers toremove more SO
2 and to generate less CCBs.
• Augmenting the capture of SO3 and other acid
gases in advanced control systems designedprimarily for NO
x, SO
2, particulates, and/or
mercury.
Figure 6. The Portfolio of Emissions Reduction Technologies in theFull Life Cycle of Pulverized Coal Electricity Generation
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GOAL:Develop control strategies for reducing thecurrent annual coal-fired utility mercuryemissions by 50 to 70% by 2005 and by 90% by2010 at a cost between one-quarter and one-half of the current cost-estimates.
Characterize mercury emissions
The program pursues characterization of mercuryemissions from coal-fired boilers in order toprovide reliable information that can serve as theunderpinning for a successful control technologyR&D effort. The characterization thrust has threecomponents: 1) measuring the levels of variousforms of mercury in flue gas, 2) studying thechemical interactions of each form of mercury withother flue gas components, and 3) developingcorrelations between the levels of various formsof mercury in flue gas and both combustionconditions and types of coal. The goal of thecharacterization effort is to provide data of thenecessary quality and scope to support effectivedecision-making about viable technologydevelopment pathways.
Develop cost-effective mercurycontrol systems
Economical capture of mercury from flue gas is adaunting challenge. The R&D effort is a three-pronged approach:
• Improve the mercury capture of existingpollution abatement systems through
-conversion of elemental mercury towater-soluble forms
-additives to enhance mercury captureacross ESPs and fabric filters
• Add adsorbents to the flue gas to capture themercury using
-carbon-based adsorbents- flyash carbon-noble metals
• Identify and evaluate novel concepts
As researchers have studied the problem andexperimented with options for mercury reduction,the estimated cost of emissions reduction havecome down. Recent cost estimates for a 90%reduction in mercury emissions from all U.S. coal-
Most flue gas streams from coal-fired electricitygeneration systems contain trace amounts ofmercury, on the order of 1 part per billion. Mer-cury, some forms of which bioaccumulate, is aneurotoxin. The effects of mercury emissions onhuman health, especially related to ingestion ofmercury-contaminated fish, have recently becomean issue of concern. In 1997, EPA submitted areport to Congress suggesting a “plausible link”between mercury emissions from coal plants andmercury contamination in fish. The EPA reportalso found that coal-fired electricity generationsystems represent 32.6% of all U.S. anthropogenicmercury emissions.
The mercury issue is relatively new. Rigorousstudy of mercury emissions from power plantsbegan with the Clean Air Act Amendments of1990 (CAAA), which directed EPA to examinemercury contamination and anthropogenicemissions. The scientific understanding of issuessuch as mercury transport in the environment andthe acceptable level of mercury contamination infish and other wildlife is evolving.
The mercury element of the program has threeprimary thrusts:
• Characterize mercury emissions from coal-firedboilers,
• Develop cost-effective mercury controlsystems, and
• Provide comprehensive cost and performancedata on mercury control technologies for use inregulatory determinations.
Each is described in the following:
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fired boilers are $2.5 to $6.5 billion per year, half ofwhat they were three years ago. While thereductions are encouraging, the cost estimates arestill high and continued R&D is needed.
In 1995 the program initiated a number of pilotstudies with the goal of obtaining a fundamentalunderstanding of the chemistry of mercuryspecies in flue gas and developing new mercurycontrol technologies. This R&D phase will becompleted in 2000.
Starting in FY 2000, the AR&ET Program willacquire field test data for promising mercurycontrol technologies and will also initiate smallerpilot-scale investigations of newer concepts. Thiseffort will provide opportunities to furthercollaborate with other government agencies, theutility industry, organizations representing theutility industry, and technology developers.Research objectives are to:
• Determine mercury removal or efficiency ofpromising mercury control technologies at alarger scale
• Assess the portion of U.S. electricity generationindustry to which each mercury controltechnology is amenable, based on systemsintegration issues
• Identify the possible negative and positiveimpacts of retrofitting these mercury controltechnologies
• Rate the various technologies on the basis ofemissions control performance per cost, takinginto consideration real-world deploymentfactors that increase cost and degradeperformance.
Provide comprehensive cost andperformance data on mercurycontrol technologies
The program is working closely with EPA andEPRI to ensure the regulatory developmentprocess for mercury emissions has the benefit ofhigh-quality up-to-date information regardingboth mercury emissions from coal-fired boilers
and availableemissions controloptions. Theprogram hasundertaken thefollowing majorefforts in support ofthe regulatorydevelopmentprocess.
• Provided EPA withmercury emissionsdata from 16 coal-fired boilers–thedata that formedthe basis for theMercury Report toCongress.
• Assisted EPA bydeveloping theQuality Assuranceand QualityControl Plan for itsInformationCollection Request (ICR) in which additionalmercury emission data was gathered from coal-fired utilities.
The program will also participate in the statisticalanalysis of the ICR data. The data collectionphase of the ICR will end in June 2000.
EPA is scheduled to determine if mercury emis-sions from coal-fired power plants should beregulated by December 15, 2000. If EPA decidesto regulate utility mercury emissions, compliancewould be required by 2007. The program plans tocontinue its collaboration with EPA as theregulatory development process proceeds. Theprogram will supply EPA with updated informationas understanding of mercury emissions chemistryimproves and as better cost and performance datafrom control technologies become available.
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90% Removal ofMercury from FlueGas is a Challenge
Mercury is present in flue gas ata concentration of approximately1 part per billion. In the pipelineexample earlier, one hour of op-eration of a 300 MW coal plantfills a 100-mile-long pipe with 41million cubic feet of flue gas. Thisis roughly equivalent to the vol-ume of the Houston AstroDome.Consider that the AstroDomecould hold roughly 30 billion pingpong balls. So, analogously, 30of the 30 billion ping pong ballsare “mercury” and the technologychallenge is to sift through theAstroDome full of ping pong ballsand capture 27 of the 30 “mercury”ones (90% removal).
Ambient concentrations of ultrafine particulatematter—particulate matter with a diameter of 2.5microns or less (PM
2.5)—may be linked to both
adverse human health effects and the loss ofvisibility in national parks and other areas. Fineparticulate matter can be associated with potentialHAPs such as trace metals or organic compounds.As Figure 7 shows, there are two types ofparticulate matter emissions, primary and second-ary. The program activities address both types.
Control of larger primary particulates has im-proved dramatically over the past 30 years inresponse to the original Clean Air Act andassociated New Source Performance Standards(see Figure 8). For the future, EPA’s revision ofthe National Ambient Air Quality Standards in1997 and promulgation of the Regional Haze Rulein 1999 make future regulatory limits on anthropo-genic emissions of PM
2.5 and PM
2.5 precursors a
real possibility. In 1998 Congress called for DOEto initiate a research program to address thesetechnical and scientific issues from the standpointof the potential impact of the new PM
2.5 standard
on coal-based power systems.
Objectives
The PM 2.5
element of the AR&ET program hasthree specific research objectives:
• Elucidate source-receptor relationships andemission trends through evaluation of theconcentration and chemical and physicalcomposition of ambient fine particulate matterand precursor gases, and possibly otherpollutants of concern (e.g., ozone, mercury).
• Characterize both primary and secondary fineparticulate emissions from fossil-based powersystems to better understand their potentialimpacts on ambient air quality.
• Develop and evaluate technologies to cost-effectively control PM
2.5, should further
reductions in fossil-based power systems benecessary to address PM
2.5 health or visibility
concerns.
GOAL:Ensure that the best science and technology areavailable for any regulatory decision-makingrelated to the health and environmental impactsof ambient fine-particulate matter and regionalhaze.
Figure 7. Two Types of Particulate Matter Emissions fromCoal-Fired Boilers
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These objectives are closely related. For example,the development of source-receptor relationshipswill determine the degree to which emissions fromcoal-fired boilers must be limited to achieveambient air quality and visibility standards.Further, the research supports the NationalAcademy of Sciences recommendation todetermine the link between ambient air quality andhuman health. Developing an understanding ofthe relative impacts of the different types of PM
2.5
will also enable a prioritization of controltechnology R&D activities.
The program’s R&D activities are stronglyleveraged with funds from industry and otherstate and federal agencies. In addition, theprogram conducts a significant amount ofoutreach, recently becoming a sponsoring memberof NARSTO, a tri-national organization thataddresses scientific and policy issues related toozone and aerosols.
The PM2.5
element conducts research in the threemain areas. These areas and their major activitiesfollow:
Ambient monitoring: PM2.5
sampling and chemical analysis
The new fine-particulate NAAQS will establish anationwide network of 1,500 PM
2.5 monitors by
2000. A small but critical subset of these stationswill include “supersites” that will sample for anarray of chemical species on a more frequentsampling interval. DOE has worked with keystakeholders, including the EPA, local and state
environmental agencies, academia, and industry,in establishing and operating several of thesePM
2.5 sites. Project sites include the Upper Ohio
River Valley Region, the Great Smoky MountainsNational Park in Tennessee, and the Bravo projectin Big Bend National Part in Texas. The program isworking to expediate sharing of data and othercollaborative activities among the differentfacilities. Figure 9 shows the location of theseand other projects in the Ambient Monitoringeffort.
Emissions characterization andPM2.5 atmospheric chemistry
The program seeks to 1) characterize fine particu-late emissions from fossil-fuel-based powersystems with the goal of producing a well-definedsource emissions inventory, 2) continue todevelop and evaluate new fine particulateemissions sampling methods to gain the mostaccurate results, and 3) study plume and atmo-spheric chemistry to better understand thereaction pathways of secondary fine particulates.
Control technology research anddevelopment
A critical component of the PM2.5
element is thedevelopment of cost-effective control technologyto be implemented should further restrictions beplaced on emissions from coal-based powersystems. The control system development effortis focused on three types of emissions: primaryparticulates, NO
x, and acid gases.
9
Figure 8. Emissions of Particulate Matter from Coal-Fired Power Plants
Avera
ge
lbs
of
PM
per
mm
Btu
Th
ou
san
ds
of
ton
sp
er
year
-
500
1,000
1,500
2,000
1970 1975 1980 1985 1990 1995 1997
0.0
0.1
0.2
0.3
0.4
0.5
short tons
lb/MMBtu
Upper Ohio River
Valley Project
(UORVP)
Southeastern AerosolResearch and
Characterization Program(SEARCH)
Bravo Project
Great Smoky Mountains
Project (GSMP)
Aerosol Research Inhalation
Epidemiology Study (ARIES)
Stuebenville Comprehensive Air
Monitoring Project (SCAMP)
DOE-NETL Primary Funding
DOE-NETL Cost-sharing
Primary particulate matter. The majority of coal-fired electric utility boilers in the United Statescontrol primary particulates with ESPs. A smallerbut growing number of boilers employ fabric filtercollectors (baghouses). However, even with high-performance particulate-control systems, collec-tion is less efficient in the submicron particle sizerange. Also, increased age of existing systems hasled to decreased collection efficiency, as hasswitching to higher resistivity low-sulfur coals.The R&D efforts encompass both stand-alonePM
2.5 capture systems and upgrades/add-ons to
commercial control systems.
NOx (secondary particulate precursor). Flue gas
contains various levels of NOx depending on the
type of boiler, coal type, existence of combustioncontrols (e.g., low NO
x burners) and other factors.
NOx emissions are regulated as a part of the Clean
Air Act and, in addition to causing formation ofsecondary fine particulates, NO
x is linked to
ground-level ozones and eutrophication of lakes.Several NO
x control R&D projects have been
funded under the auspices of the fine particulatesprogram. NO
x emissions and controls are
discussed further in the NOx, SO
x program
summary.
Acid gases (secondary particulate precursors).Flue gas from coal-fired boilers contains traceamounts of acid gases such as SO
3/H
2SO
4, HCl,
HF, and related condensable vapors that can formultrafine particles upon cooling and/or exposureto moisture within the combustion system or afterrelease from the stack. Such species, which canadversely affect plume opacity, are not typicallycontrolled in coal-fired boilers.
In the area of NOx emissions control, the program
will investigate ways to improve the performanceof advanced low NO
x burners through over fire air
and staged air configurations, as well as throughhybrid systems with selective non-catalyticreduction and other post-combustion controltechnologies. The program will also investigateoxygen and methane-enhanced combustion as ameans of NO
x control. In addition, the program
will carryout full-scale demonstration of aSelective Non-Catalytic Reduction unit (incollaboration with the Ohio Coal DevelopmentOffice, EPRI, American Electric Power, and 14other utilities).
10
Figure 9. DOE Ambient PM2.5
/Air Toxics Sampling andAnalysis Projects
The removal of fly ash, sulfur dioxide, and otherspecies from flue gas results in the production ofsolid materials, referred to as coal combustion by-products (CCBs). CCBs have many interesting and
11
LSR Technologies’ Core Separator
In the early 1990’s, the AR&ET Program provided funding to LSR Technologies, Inc. for thedevelopment of its Core Separator, a mechanical particulate control system. The research wasa success, and in 1996 the Core Separator earned LSR Technologies one of R&D Magazine’sprestigious R&D 100 Awards. Initial commercial applications for the Core Separator have beenmostly industrial boilers. Recently, LSR Technologies developed the ElectroCore systemwhich is designed to be retro-fitted into coal-fired electricity generation systems with ESPunits. In the ElectroCore system, an ESP is integrated with a Core Separator to achieve a highdegree of particulate separation (especially fine particulates) at low incremental cost. InAugust of 1999, the AR&ET Program awarded LSR Technologies $1.2 million to demonstrateits ElectroCore fine-particulate-separation technology at the pilot scale at Alabama PowerCompany’s Gaston Stream Plant.
In the area of primary particulate emissionscontrol, the program will investigate flue gasconditioning agents to improve ESP performance,hybrid ESP/fabric filter systems, and electrostati-cally enhanced core separator retrofit systems(see box on the next page). In the area of acid gasemissions control, the Program will investigate in-furnace injection of alkaline chemicals.
For more information on the R&D performancetargets, solicitation activity, and backgroundinformation related to the PM
2.5 element, visit the
Particulate Matter and Air Toxics ResearchProgram website at www.netl.doe.gov/products/power/enviro/pm25.
The removal of fly ash, sulfur dioxide, and otherspecies from flue gas results in the production ofsolid materials, referred to as coal combustion by-products (CCBs). CCBs have many interesting anduseful properties. However, due to both liabilityconcerns and the limited number of provenutilization options, electricity generators havehistorically opted to landfill CCBs rather than try tosell them as a commodity. Figure 10 shows that thegeneration of CCBs in the United States has beenincreasing steadily with both increasing coal useand more stringent environmental regulations, andthat only a small percentage of the total generationis utilized. In 1998 seventy-seven million tons ofCCBs were disposed of landfills in the UnitedStates, roughly 71% of the total production, at acost of roughly $1 billion.
With increased focus on cost-cutting in a competi-tive market, electricity generators have recentlybecome more interested in utilizing CCBs. From theperspective of DOE, value-added CCB applicationscan reduce the overall cost of environmentalcontrols and maintain low-cost energy production.Also, the utilization of CCBs can reduce CO
2
emissions by avoiding the energy needed toproduce displaced virgin material.
The activities of the CCB program element can bebroken into three interrelated thrusts:
• Developing new applications for CCB materials• Evaluating the impact of air emission control
technologies on CCB properties• Providing field test data for use in regulatory
matters pertaining to disposing of or using CCBs.
Developing new applications forCCB materials
The program efforts on developing new options forCCB disposition are broken into three categories.
• Construction materials-Lightweight aggregate-Road construction
• Beneficial land application-Agricultural lime substitute/soilamendment
-Surface mine reclamation-Livestock feedlot stabilization
• Underground mine emplacement-Surface mine highwall stabilization-Underground mine subsidence control-Acid mine drainage abatement
It is anticipated that additional SO2
scrubbers will be deployed over thenext 10 years to comply with CAAAand other air emission regulations,resulting in the production of signifi-cantly more flue-gas desulfurization(FGD) by-products. Based onprojected scrubber capacity, theannual generation rate of FGD materialcould increase from 25 MM tons (25%of all CCBs) in 1998 to 75 MM tons(50% of all CCBs) in 2010. In 1998only 10% of FGD material generatedwas utilized. Finding useful applica-tions for FGD material is a key focus ofthe CCB program.
GOAL:Increase the utilization of solid coal combustionby-products from 30% to 50% by 2010.
12
U.S
.P
rod
ucti
on
of
CC
Bs
(millio
ns
of
ton
sp
er
year)
0
20
40
60
80
100
120
1970 1975 1980 1985 1990 1995 1998
Landfilled
Utilized
Data Source: American Coal Ash Association
Figure 10. Utilization of CCBs
There are three main challenges to be overcome inthe development of an application for a CCBmaterial.
• Environment: CCBs may contain trace amountsof heavy metals and other regulated chemicalspecies. The degree to which these regulatedspecies are released into the environment, if at all,must be carefully measured for each application.
• Performance: The CCB materials must meet theperformance requirements (e.g., strength,durability) of the application.
• Economics: The costs of any neededprocessing and transport of the CCB materialmust not outweigh the revenue benefit.
In the past, the CCB program has enjoyed numer-ous successes in collaborative projects withindustry. To continue and build upon thosesuccesses, DOE has established the EmissionsControl By-products Consortium (ECBC), anindustry/government/academia partnership, to aidin managing the R&D effort and specifically toassist in the evaluation of proposals. The consortiawill enable DOE to 1) collaborate with the utilityindustry and other federal agencies, 2) considerregion-specific CCB utilization opportunities, and3) leverage funds with other entities.
Evaluating the impact of airemission control technologies onCCB properties
Air emissions abatement technologies can affectthe composition of flyash and other solid by-product streams. For example, low NO
x control
systems may increase the carbon content of
flyash and/or contaminate it with trace amounts ofammonia, in some cases making it unsuitable foruse in concrete. Also, systems used to capturemercury from flue gas may increase the mercurycontent of CCBs, causing potential environmentalconcerns in certain applications. In the future, theCCB utilization program will focus on characteriz-ing any changes that occur in CCB materials andmaintaining the utilization of CCBs in key applica-tions.
Providing data for use inregulatory matters pertaining todisposing of or using CCBs
In some cases perceived environmental risksassociated with CCB use are a significant barrierto CCB utilization. To overcome this barrier, theprogram has performed numerous field tests withrigorous monitoring of the degree to whichspecies of concern are released into the environ-ment. The program supplies such information toEPA and other federal agencies.
EPA is currently determining the environmentalacceptability of using CCB materials and whatmanagement/utilization practices are allowable.The program has supplied EPA with high-qualitydata obtained from field tests that show minimalenvironmental impacts. It will continue to provideEPA with data as it becomes available.
13
Production of Construction Aggregates from FGDBy-product Material Shows Promise
In a cost-shared effort with CONSOL Incorporated, DOEis demonstrating conversion of a mixture of FGD by-product and flyash into manufactured aggregates that aresuitable for high-volume construction purposes (seeprocess diagram at right). Initial results are promising,and CONSOL is designing and building a 500 lb/hr pilotplant to demonstrate its proprietary process on a largerscale.
GOALS:90% or greater NO
x emissions reduction from
coal-fired boilers at low cost and 95% removalof SO
x from flue gas.
The term NOx refers to oxides of nitrogen (NO,
NO2); similarly SO
x refers to both SO
2 and SO
3.
The emissions of SO2 and NO
x from electricity
generation boilers are directly regulated as a partof Title IV of the CAAA. As a result of advancedcontrol technologies and coal switching,emissions of NO
x and SO
2 from coal-fired power
plants have been reduced (see Figure 11).Emissions of SO
3 and other acid gases may be
regulated in the future, and the program elementname has been changed from NO
x and SO
2 to NO
x
and SOx to reflect the significance of SO
3
emissions.
The Department of Energy, in partnership withindustry, has been successful in developingretrofit technologies that have enabled existingcoal plants to comply with CAAA at relatively lowcost. Most notably, low-NO
x burners offer a 50%
reduction in NOx emissions at an incremental cost
of roughly 0.03 cents per kWh ($200/ton NOx).
The program has also developed technology thatenhances the performance of SO
2 scrubber
systems (see page 15).
Although the technologies employed to complywith Phase I of Title IV (e.g., wet scrubbers, low-NO
x burners) are considered mature, tighter
restrictions on NOx and SO
x emissions are on the
horizon. Two points demonstrate that this will bethe case. First, the SO
2 emissions limits imposed
by Title IV are an absolute cap. Over the comingyears as stockpiled allowances expire and as coaluse increases along with economic growth,
14
Figure 11. NOx and SO
2 Emissions from Coal-Fired Power Plants in the U.S.
Th
ou
sa
nd
so
fs
ho
rtto
ns
/y
r
Th
ou
sa
nd
so
fs
ho
rtto
ns
/y
r
Av
era
ge
lbs
NO
pe
rm
mB
tuX
Av
era
ge
lbs
SO
pe
rm
mB
tu2
SO2
-
5,000
10,000
15,000
20,000
1970 1975 1980 1985 1990 1995 1997
0.0
1.0
2.0
3.0
4.0
5.0
short tons
lb/MMBtu
NOx
-
2,000
4,000
6,000
8,000
1970 1975 1980 1985 1990 1995 1997-
0.20
0.40
0.60
0.80
1.00
1.20
short tons
lb/MMBtu
Title IV limits will become more restrictive.Second, NO
x and SO
x have been identified as
precursors to fine particulate matter, and NOx as a
precursor to ground-level ozone; regulationsdesigned to improve ambient air quality mayrequire cuts in NO
x and SO
x emissions well below
the proposed Title IV levels. For example, as apart of a State Implementation Plan to reduceground-level ozone (NO
x SIP), 19 eastern states
are required to reduce NOx emissions from existing
boilers to 0.15 lb/mm Btu coal during the summer-time ozone season (May-September). As acomparison, the NO
x emissions limits under the
Acid Rain Program range from 0.4-0.86 lbs/mmBtu, depending on the boiler type.
Finally, the emissions of acid gases including SO3
may become a regulatory target as a result ofelectricity generators reporting under the ToxicsRelease Inventory. Control of acid gases would ineffect reduce the allowable emissions of SO
2
because of the similarity of the chemical species’reactivity. (99% of sulfur emissions from coal-fired boilers are in the form of sulfur dioxide, butthe remaining 1% is mostly SO
3, which forms
sulfuric acid upon contact with water.)
Because NOx is a precursor to ambient fine
particulate deposition, advanced NOx control
technologies are also being developed under theauspices of the fine particulate matter program.The technologies are to be ready for commercialdeployment by 2002-2004, which would enablethem to be utilized by U.S. utilities for compliancewith the NO
x SIP call. Specific requirements for
the NOx reduction technology development are to
1) reduce NOx emissions to 0.15 lb/ mm Btu at a
cost 25% lower than an SCR, 2) have negligibleimpact on balance-of-plant issues, 3) be applicableto a wide range of boiler types and configurations,and 4) maintain performance over a wide range offeed coals and operating conditions.
Coal-fired power plants will likely be required toreduce SO
2 and SO
3 emissions below Title IV
requirements over the next 5-10 years. Concernsover the effects of NO
x emissions may prompt
lower year-round NOx emissions standards as
well. The AR&ET Program will continue todiscuss technology development needs and
Field Test of Advanced Scrubber Technologyat Duquesne Power and Light’s Elrama
Power Station is a Big Success
The addition of thiosufate to the scrubbingliquor of a flue gas desulfurization system in-hibits sulfite to sulfate oxidation and the for-mation of gypsum scale. A field test cospon-sored by DOE demonstrated that increasingthe concentration of thiosulfate in the scrub-bing liquor from 500 ppm (the established op-erating level) to 2000 ppm, improved the scrub-ber efficiency 1%, reduced the amount of limeused by 10%, and virtually eliminated scalebuildup. The project is saving the plant$574,000 per year: $84,000 in extra sulfur diox-ide allowances from the improved scrubber ef-ficiency (based on current market value);$220,000 from reduced lime use, and $270,000from reduced maintenance cost. Says EgonKlatt a 35-year veteran at Duquesne Light,“Some people would call it a home run. I call ita grand slam.”
15
opportunities regarding SO2 and NO
x control with
technology developers, utility companies, andother stakeholders.
A possible basis for tighter emissions standardsis the deposition of NOx from power plantemissions to water bodies. Nitrogen in freshwater causes eutrophication (nutrient overload-ing), which causes algae to grow rapidly anddeplete the oxygen in the water. Low oxygenconcentration causes fish kills, odor, and otherproblems. The agriculture industry was firstidentified as the primary source of nitrogen over-loading in fresh water systems, and initial actionto lower nitrogen concentrations focused onregulating the storage and use of animal wastes.However, a 1998 report National Acid Precipita-tion Assessment Program Biennial Report toCongress: An Integrated Assessment by NSTCfound that between 10 and 45% of nitrogen inestuaries along the Atlantic and Gulf Coast iscaused by atmospheric deposition. Thus futureregulations designed to protect fresh waterresources may be focused on sources of atmo-spheric nitrogen, such as power plants andautomobiles.
III. Program Management
16
This section presents the management objectivesof the AR&ET Program, including the programstrategy, R&D portfolio, portfolio criteria, andstakeholder outreach activities. It provides theprogram timing and major milestones.
A. Program Role and Strategy
A program that encompasses R&D on a diverseportfolio of technologies offers the best chance ofsuccess for reducing risks and ultimate environ-mental-control costs to the United States. Inimplementing this portfolio, significant industryparticipation is essential for all phases of theprogram, through workshops, advisory panels,competitive awards, and cost-shared partnerships.
The AR&ET program has two major roles:
• Developing advanced environmental controltechnology for coal-fired power plants
• Providing high-quality data and analysis toEPA, OMB, Congress, and others for use inregulatory determinations.
A major portion of the program’s R&D is awardedthrough competitive solicitations involvingindustry, universities, and national laboratoryperformers. For example, in 1999 the programissued a major solicitation titled Emission ControlTechnology for Fine Particulate Matter (PM
2.5)
Ozone, and Related Environmental Issues fortechnologies, processes, and concepts that canbe retrofitted to existing coal-based powersystems. In March 2000, the program issued asolicitation for field-testing of promising mercurycontrol technologies. Through these solicitationsthe program seeks to partner with industry todevelop innovative technical approaches toensure that domestic coal can remain an environ-mentally sound component of the United States’overall energy mix well into the 21st century.
High-quality data is critically important to ensurethat regulations provide improvements in healthand the environment and that those improvementsare commensurate with the cost of compliance.The AR&ET program provides valuable input
because it is both objective and technicallycapable of developing the pertinent data andanalysis.
B. Portfolio Approach toManagement
The program activities are managed as a portfolio,recognizing that knowledge about this field ofscience and technology is rapidly evolving. Byapplying portfolio theory to the management ofprogram resources, the probability of success inachieving program goals is increased.
The portfolio will be managed with an increasingemphasis on the critical outcomes of flexibility andintegration potential, because integration ofcontrols for multiple emission species is the mostlikely path to achieve environmental acceptabilityat low costs.
C. Stakeholder Outreach andPartnerships
Environmental compliance of existing coal-firedboilers is an important issue for U.S. utilities, andthere is strong support and interest for theprogram within the power generation industry.Through cost-shared R&D projects, industry/government consortia, and informal advisoryrelationships, the private sector is tangiblyinvolved in the program. As new environmentalissues affecting the power industry arise, theprogram funds workshops to garner industryinput and works with other agencies of theFederal Government to identify R&D needs andother opportunities for the program. Also,coordination and cooperation with other govern-mental entities enables the program to leveragefunds.
Recent outreach activities include:
• Provided technical and programmaticinformation to the National Research Council inits review of the DOE Fine Particulate ResearchPlan
Program Portfolio Criteria
Critical Outcomes• Low cost. The expected cost of the commercial technology, in terms of both capital costs and
operations and maintenance costs.• Environmental acceptability. The expected compatibility with the environment, including
protection of human health and sensitive ecosystems.• Control of multiple pollutants. The ability of the technology to simultaneously control different
emission species.• Flexibility Potential. The ability of the technology to be used with a wide range of plant configu-
rations and sites, both new and retrofit.
Supporting Outcomes• Likelihood of success. The probability of meeting the performance objectives of the research
activity.• Multiple benefits. The degree to which the activity is likely to produce other benefits (e.g.,
international market competitiveness for technology products and services) in addition toenvironmental acceptability.
• Program balance. The degree to which the activity complements the scope, timing, risk, anddiversity of the portfolio.
• Program enhancement. The degree to which the activity identifies and makes progress on newconcepts, thereby increasing the likelihood of a successful program.
• Partnerships. The participation (financial, intellectual, and programmatic) of other researchsponsors, including industry and international partners.
• Leveraging. The aggregate cost-sharing by non-FE participants.• Visibility. The potential for the activity to attract favorable attention to the FE R&D program.
• Launched a PM2.5
web page which providesbackground information on the fine particulateissue, a discussion of the program’s goals andobjectives, and updates on ongoing R&Dprojects, the ambient air monitoring program,and solicitation activity
• Published a technical review of theEnvironmental Protection Agency’s MercuryReport to Congress, focusing on EPA’sevaluation of mercury control technology andcost
• Published a critical review of mercurymeasurement and control technology in theJournal of the Air & Waste ManagementAssociation
17
Planned outreach activities include:
• Participate in the Air Quality Subcommittee, aCongressionally mandated group thatcoordinates all Federal activities in air quality
• Cosponsor, with the Office of Surface Mining,Department of Interior, an Interactive Forum onCCB Utilization in Mining.
D. Program Timing andMilestones
In the near term (less than five years), the programwill continue to examine emissions-specifictechnology needs and solutions while assessingthe opportunities for integrated control strategies.In the mid term (five to ten years), the program willfocus on the evaluation and development ofintegrated control strategies and systems that canyield the cost-effective technologies that arerequired. The long-term (beyond ten years) focusis on ground-breaking concepts for a costreduction in systems, including systems with bothlow capital cost and very low operations andmaintenance costs. Figure 12 shows majoractivities and milestones for the program over thenext five years.
Figure 12. AR&ET Program Milestones
Field Test Hg Control Tech.
Reduce Regulatory Impactson Byproducts Util. (BBA)
Initiate ByproductsConsortium (ECBCa)
1999 2000 2001 2002
Advanced NO Control TechnologiesPerformance Evaluations
600 MW SNCREvaluation
SupercleanEmissions
Fine ParticlesAir Toxics
Coal CombustionByproducts
Completein 2003
Completein 2004
Ambient PM Characterization2.5
PM2.5 Control Tech. Development
2003
ECB 2nd Round
x
18
E. Program Costs
The AR&ET program budget for FY 2000 is 23.8million dollars, which includes 9.2 million dollarsfor carbon sequestration R&D activities. Thenon-sequestration budget, 14.6 million dollars, isnearly double the 1998 funding level. Futureprogram funding will depend on regulatoryactivity and the level of national interest inreducing the detrimental effects of coal utilizationto ensure its continued use as an energy source.
IV. Program Benefits• Low-NO
x burners. In 1997 over half the coal
burned in the United States was burned in aLow-NO
x burner. Developed with DOE funding,
this technology provides a 50-65% reduction inNO
x emissions at a cost of roughly 200 $/ton.
As a comparison, a selective catalytic reductionsystem costs 1,500-2,000 $/ton.
• Advanced SO2 Scrubbers. The AR&ET
Program conducted field tests demonstratingthat very minor operational changes to alimestone scrubber could improve the sulfurdioxide removal efficiency. The incrementalcost of sulfur dioxide capture from suchchanges can be as low as 50 $/ton. With thesoft market for SO
2 allowances and other
pressing environmental and deregulationissues, commercial interest in advancedscrubber technology has been low. However,this technology will be critical in keeping thecost of sulfur emissions reductions low asTitle IV comes into effect and as more stringentSO
2 emissions regulations are promulgated to
meet PM2.5
and ozone air quality standards.
• High-quality information on toxics emissions.Working with EPRI, DOE developed much moreaccurate air emissions factors for heavy metalsand other toxic species than were currentlyavailable. These correlations showed muchlower emissions of toxic materials in the flue gasfrom coal-fired boilers than the correlations
Figure 13. The Cost of Compliance with Environmental Regulations isProjected to Increase Sharply Over the Next Ten Years
19
The aggregate cost of environmental compliancefor coal-fired electric generators in the UnitedStates was 1.9 billion dollars in 1997 and isprojected to balloon to more than 13 billion dollarsper year by 2010 (see Figure 13). Regulations ofHAP emissions and the Regional Haze Rule,which are not included in the 2010 estimate, couldraise compliance costs higher. Thirteen billiondollars per year in 2010 is roughly equivalent to0.6 cents per kWh of electricity generated fromcoal, which would be a 60% increase over thebaseline average fuel cost of 1.0 cent per kWh.
The AR&ET program benefits are based onlowering the cost of environmental compliance forcoal-fired electric generators. If the program goalof a 50% reduction is achieved it will save6.5 billion dollars per year.
A. Retrospective
As shown in Figure 14, the cost of electricity hasdecreased from an average of 9.2 cents per kWh in1985 to 6.9 cents/kWh in 1997 while coal use hasincreased. Cost reductions continue, and theincreased reliance on coal plays a large role inenabling the lower energy prices.
Over the past 20 years, technologies developedby the program have helped keep the cost of coal-fired generation low. The following are examples.
sanctioned by EPA. Based on the rigor andvalidity of the new emissions factors, the powerindustry was able to avoid both unwarrantedregulations due to overreporting toxicemissions and expensive stack testingestimated to cost $50 million.
• High-quality information on CCB utilization.Working with a wide variety of partners, DOEdemonstrated that CCBs do not releasesignificant quantities of hazardous constituentsinto the environment, leading EPA to determinethat regulation of large-volume CCB materials asa hazardous waste was not warranted.Utilization rather than disposal of CCBs canresult in a cost savings ranging from $2/ton to$30/ton. At a current utilization rate of 30million tons per year, the total savings due toCCB utilization ranges from $60 million to $900million per year.
B. Future
The AR&ET Program looks forward to providingsimilar successes in the future as the electricitygeneration industry addresses the challenge ofincreasingly stringent air emissions regulations.The program goal is to reduce the cost of compli-ance by 50% through the development of new
abatement technologies and integrated systems.If this goal is achieved, it will provide savings of6.5 billion dollars per year by 2010.
Benefits are expected to be even greater interna-tionally. Developing nations are currentlydeploying inexpensive coal-fired power plantswith relatively poor environmental performance.As the standard of living rises in these nations,environmental awareness will increase, creating asubstantial need for retrofit systems to improvethe environmental performance of existinggeneration assets. Low-cost, environmentallyclean coal-fired power systems will also be neededto meet future growth in demand.
A successful program will produce great benefits:
• Continued consumer savings from the use ofthe most economic source of power—domesticcoal
• Continued improvement in ambient air quality• Technology solutions for large, emerging global
market applications to maintain U.S. leadershipin the export of electric-power generationtechnology and services
• Effective environmental technology that willenable the U.S. to maintain energy diversity in aderegulated electric supply industry.
Figure 14. Since 1985 Coal Use has Increased While the Cost of Electricity has Gone Down
20
Co
al
Us
e,
Qu
ad
rill
ion
Btu
pe
ry
ea
r
Av
era
ge
Co
st
of
Ele
ctr
icit
y,
ce
nts
/kW
h
0
3
5
8
10
13
15
18
20
1985 1990 1995 19970
1
2
3
4
5
6
7
8
9
10
Quadrillion Btu
cents/kWh
Appendix A. Key Regulatory DriversThe development of emissions abatementtechnology for coal-fired boilers is driven byemissions regulations. The original Clean Air Actwas passed in 1963 but no significant actionsoccurred until the passage of the Air Quality Actin 1967, which required all coal-fired units toinstall either electrostatic precipitators orbaghouses to capture particulate matter from theirflue gas. Within 15 years, the total U.S. emissionsof particulate matter from coal-fired boilers wasreduced by 85%.
The Clean Air Act Amendment of 1970 set limitson the amount of particulate matter (0.1 lbs/mmBtu), sulfur dioxide (1.2 lbs/mmBtu), and oxidesof nitrogen (0.7 lbs/mmBtu) that could be emittedby newly constructed or re-powered coal-firedboilers, so called New Source PerformanceStandards (NSPS). Also, Congress gave EPA theauthority to determine National Ambient AirQuality Standards (NAAQS) which are theallowable concentrations of certain chemicalspecies in ambient air that do not pose a signifi-cant threat to human health. Each state was todevelop a State Implementation Plan (SIP), forlimiting air emissions to meet the air qualitystandards, but EPA was given a strong oversightrole in the development of these plans.
In response to legislative directives in the 1984Amendments to the Resource Conservation andRecovery Act, EPA published a final determinationin 1993 that regulation of large-volume coalcombustion by-product streams as a hazardouswaste was not warranted. Under a consent decreeEPA was to determine the status of the remainingCCB wastes in 2000. In the 1999 Report toCongress, Wastes from the Combustion of FossilFuels, EPA recommendations indicated that thesematerials would not be listed as hazardous. EPAdid question the acceptability of two otherwiseattractive and potentially high-volume applica-tions of CCBs, acid mine remediation and agricul-tural soil amendment. Due primarily to environ-mental concerns about the release of HAPs,indications in early 2000 were that EPA mightconsidering regulating these wastes as hazardousunder RCRA Subtitle C. Under considerablepressure from legislators and certain governmentagencies, EPA’s final ruling was not to regulate
the materials as hazardous, but instead todevelop standards under RCRA subtitle D (non-hazardous solid waste) for the disposal of fly ash,boiler ash and scrubber sludge.
Title IV of the Clean Air Act Amendments of1990 established the Acid Rain Program, aphased, allowance-based system for achievingreductions in emissions of NO
x and SO
2 from coal-
fired boilers. Phase 1 of the Acid Rain Programregulations came fully into effect on January 1,2000. In response to this program, industry hasmade significant changes to existing plantsincluding widespread switching to low-sulfursubbituminous coal and installation of low-NO
x
burners as well as the retrofit installations of anumber of limestone scrubbers and selectivecatalytic reduction units. More investments areexpected as Phase II comes into effect. In the1990 Amendments, Congress also directed EPA totake regulatory action on regional haze and tostudy anthropogenic emissions of mercury in theUnited States.
EPA recently promulgated two air regulationsunder the CAAA that could have significantimpacts on coal-fired boilers. In 1997, EPAtightened the NAAQS for ground level ozone, andalso established an air quality standard forultrafine particulates (i.e., less than 2.5 microns indiameter, PM
2.5). Separately, in 1999 EPA issued
the Regional Haze Rule, setting a goal ofreaching natural background visibility conditionsin national parks and other mandatory Class Ifederal areas within 60 years. The rule citesultrafine particulate matter as the primary cause ofhaze. NO
x is a precursor to both PM
2.5 and
ground-level ozone, so both of these regulationsimply more stringent limits on NO
x emissions from
coal plants. The eastern United States hasparticularly acute problems with ozone in theground-level air, and a recently approved SIP forground-level ozone requires all coal-fired electric-ity generation units in 19 eastern states to achievean average NO
x emissions rate of 0.15 lb NO
x/
MMBtu by 2003, effectively mandating wide-spread retrofit installations of selective catalyticreduction units over the next several years.Sulfur trioxide and other acid gases have been
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identified as precursors to fine particulates aswell. As a result, the regional haze and PM
2.5 air
quality regulations may require sulfur emissionsreductions below the Acid Rain Program limits.
In 1997, EPA expanded the Emergency Planningand Community Right-to-Know Act of 1986(EPCRA) reporting requirements to includeelectricity generating facilities, among others.EPCRA requires certain facilities that manufacture,process, or otherwise use listed toxic chemicals toreport their environmental releases of suchchemicals annually. The results are produced inthe Toxic Chemical Release Inventory (TRI), andin the past have lead to significant public atten-tion and pressures to further reduce limits on thereleases. The first reports from coal-fired facilitieson the release of toxic chemicals were due to EPAon July 1, 1999, the results of which have not yetbeen published by EPA. However the largequantities of acid gases (hydrochloric acid (HCl)and sulfates (SO
3)) released in the generation of
electricity may cause public reaction and lead totightened restrictions or reporting requirements.
In a 1997 report to Congress, EPA suggested aplausible link between mercury emissions fromcoal-fired power plants and mercury contamina-tion in fish. The report stated that EPA has set agoal of reducing U.S. anthropogenic emissions ofmercury by 50% by 2005. Because coal-firedelectricity generation units represent 32.6% of allU.S. mercury emissions, future regulation of theseemissions from coal-fires boilers is likely. In 1998,EPA issued an Information Collection Request(ICR) requiring all U.S. coal utilities to sampletheir coal once per week for one year and test formercury content. Also, 75 randomly selected coalutilities had to conduct a series of four stack teststo measure their emissions of mercury. In 1999EPA lowered the deminimis reporting requirementfor certain persistent bioaccumulative toxicchemicals (PBTs), including mercury and dioxins.The requirements for mercury were decreasedfrom 10,000 to 10 pounds, which will now compelmost coal-fired facilities to report mercuryreleases.
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Under the Clean Air Act, certain facilities are“grandfathered” or made exempt from CAAregulations due to age and technology. Under thelaw these facilities are allowed to conduct routinemaintenance, but according to New SourceReview (NSR) requirements they must installemissions control technologies if plant modifica-tions result in overall emissions increases. OnNov 3rd, 1999 EPA announced major legal actionagainst 32 coal-fired power plants in ten states foralleged violations of the NSR rules. At issue areactivities at the facilities that have been filed asroutine maintenance, but which EPA claimsconstitute repowering. The alleged violations ofthe eight companies span several decades andcould amount to extraordinary fines. In settlementdiscussions, EPA is seeking commitments torepower to new fuels, close down the morepolluting units, enforce tighter emissions, andestablish environmentally-friendly projects.Tampa Electric Company (TECO) is the onlycompany to reach an agreement with EPA, theremaining seven are still in negotiations or court.The agreements or settlements when reachedcould have an effect on the New Source Perfor-mance Standards (NSPS), resulting in morestringent emissions requirements, greenfieldfacilities, and fuel switching.
Clearly, environmental regulations of coal-firedgenerators have become more stringent over thepast 30 years, and the trend is toward furthertightening of emissions limits. New ideas andintegrated solutions are needed to address bothpresent and future environmental requirements ina cost-effective manner.
For more information on the AR&ET Program, please visit our web sites:
• DOE Office of Fossil Energy @http://www.fe.doe.gov/coal-power/environ/environ.sum.html
• DOE National Energy Technology Laboratory @http://www.netl.doe.gov/products/power/environ.html
or contact:
David BeecyOffice of Environmental Systems
Office of Fossil Energy(301) 903-2786 or
Chuck SchmidtNational Energy Technology Laboratory
Office of Fossil Energy(412) 386-6090 or
U.S. Department of EnergyOffice of Fossil Energy
National Energy Technology LaboratoryPittsburgh, Pennsylvania
Morgantown, West Virginia
