Best Available Control Technology Research Articles

Characteristics of PM and PAHs emitted from a coal-fired boiler and the efficiencies of its air pollution control devices

ABSTRACT Sampling and analysis of filterable particulate matter (FPM), FPM2.5, condensable particulate matter (CPM), polycyclic aromatic hydrocarbons (PAHs), sulfur oxides (SOx) and nitrogen oxides (NOx) emitted from a coal-fired boiler equipped with selective catalytic reduction (SCR)+ electrostatic precipitator (ESP) + wet flue gas desulfurization (WFGD) + wet electrostatic precipitator (WESP) as air pollution control devices (APCDs) are conducted. The results show that NOx concentration emitted from the coal-fired boiler is 56 ± 2.17 ppm (with the NOx removal efficiency of 47.2%), which does not meet the best available control technology (BACT) emission standard (≤ 30 ppm). On the other hand, the WFGD adopted has a good removal efficiency for SOx and HCl. Both SOx and HCl emission concentrations are <1 ppm, and removal efficiencies are >99%. The FPM and FPM2.5 emitted from the coal-fired boiler are 0.9 ± 0.06 mg/Nm3 and <0.09 ± 0.006 mg/Nm3, respectively. The overall removal efficiency of FPM achieved with ESP+WFGD+WESP+MGGH is 99.98%. However, high concentration of CPM (37.4 ± 6.3 mg/Nm3) is measured, which is significantly higher than FPM and FPM2.5. The concentrations of 27 PAHs at the WESP inlet and stack are measured as 667 ng/Nm3 and 547 ng/Nm3, respectively while the removal efficiencies of gas- and solid-phase PAHs are 9% and 58%, respectively. The results show that APCDs adopted are not effective in removing PAHs (only 18%), and gas-phase PAHs contribute the most in the total PAH emission. In addition, the benzo(a)pyrene equivalent (BaPeq) concentration emitted from the stack is 28.8 ng-BaPeq/Nm3, and most of it is contributed by 4-6 ring PAHs with high toxic equivalent factors (TEFs). Furthermore, the emission factors of air pollutant emitted from coal-fired boilers equipped with different combinations of APCDs are compiled and compared. The results show that except for CPM and NOx, the emission factors of air pollutant calculated for this coal-fired boiler are lower if compared with other studies.

Modeling methane oxidation in landfill cover soils as indicator of functional stability with respect to gas management

ABSTRACTA performance-based method for evaluating methane (CH4) oxidation as the best available control technology (BACT) for passive management of landfill gas (LFG) was applied at a municipal solid waste (MSW) landfill in central Washington, USA, to predict when conditions for functional stability with respect to LFG management would be expected. The permitted final cover design at the subject landfill is an all-soil evapotranspirative (ET) cover system. Using a model, a correlation between CH4 loading flux and oxidation was developed for the specific ET cover design. Under Washington’s regulations, a MSW landfill is functionally stable when it does not present a threat to human health or the environment (HHE) at the relevant point of exposure (POE), which was conservatively established as the cover surface. Approaches for modeling LFG migration and CH4 oxidation are discussed, along with comparisons between CH4 oxidation and biodegradation of non-CH4 organic compounds (NMOCs). The modeled oxidation capacity of the ET cover design is 15 g/m2/day under average climatic conditions at the site, with 100% oxidation expected on an annual average basis for fluxes up to 8 g/m2/day. This translates to a sitewide CH4 generation rate of about 260 m3/hr, which represents the functional stability target for allowing transition to cover oxidation as the BACT (subject to completion of a confirmation monitoring program). It is recognized that less than 100% oxidation might occur periodically if climate and/or cover conditions do not precisely match the model, but that residual emissions during such events would be de minimis in comparison with published limit values. Accordingly, it is also noted that nonzero net emissions may not represent a threat to HHE at a POE (i.e., a target flux between 8 and 15 g/m2/day might be appropriate for functional stability) depending on the site reuse plan and distance to potential receptors.Implications: This study provides a scientifically defensible method for estimating when methane oxidation in landfill cover soils may represent the best available control technology for residual landfill gas (LFG) emissions. This should help operators and regulators agree on the process of safely eliminating active LFG controls in favor of passive control measures once LFG generation exhibits asymptotic trend behavior below the oxidation capacity of the soil. It also helps illustrate the potential benefits of evolving landfill designs to include all-soil vegetated evapotranspirative (ET) covers that meet sustainability objectives as well as regulatory performance objectives for infiltration control.

NSR Enforcement Litigation: What You Need to Know

The New Source Review (NSR) program of the Clean Air Act requires major stationary sources to go through an extensive, time‐consuming, and expensive review and permitting process prior to construction. Among other requirements, such sources are required to install the best available control technologies (BACT) to reduce levels of specific regulated pollutants. The NSR program also applies to existing facilities if they are modified in substantial ways and if, as a result, emissions increase by significant amounts (these are known as “major modifications”).

Economic implications of incorporating emission controls to mitigate air pollutants emitted from a modeled hydrocarbon‐fuel biorefinery in the United States

AbstractThe implementation of the US Renewable Fuel Standard is expected to increase the construction and operation of new biofuel facilities. Allowing this industry to grow without adversely affecting air quality is an important sustainability goal sought by multiple stakeholders. However, little is known about how the emission controls potentially required to comply with air quality regulations might impact biorefinery cost and deployment strategies such as siting and sizing. In this study, we use a baseline design for a lignocellulosic hydrocarbon biofuel production process to assess how the integration of emission controls impacts the minimum fuel selling price (MFSP) of the biofuel produced. We evaluate the change in MFSP for two cases as compared to the baseline design by incorporating (i) emission controls that ensure compliance with applicable federal air regulations and (ii) advanced control options that could be used to achieve potential best available control technology (BACT) emission limits. Our results indicate that compliance with federal air regulations can be achieved with minimal impact on biofuel cost (~$0.02 per gasoline gallon equivalent (GGE) higher than the baseline price of $5.10 GGE−1). However, if air emissions must be further reduced to meet potential BACT emission limits, the cost could increase nontrivially. For example, the MFSP could increase to $5.50 GGE−1 by adopting advanced emission controls to meet potential boiler BACT limits. Given tradeoffs among emission control costs, permitting requirements, and economies of scale, these results could help inform decisions about biorefinery siting and sizing and mitigate risks associated with air permitting. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley &amp; Sons Ltd.

English

On April 13, 2012 and January 8, 2014, the U.S. Environmental Protection Agency (USEPA) proposed new regulations that amounted to a prohibition on the Best Technologies Currently Available for constructing new coal fired power plants. USEPA first proposed in 2012, that new coal power plants must not produce more carbon dioxide (CO2) than a natural gas power plant. Then in 2014, it revised the standard to require that unless a coal fired power plant met the same CO2 emission levels as achievable with power plants utilizing Integrated Gas Combined Cycle (IGCC) combustion technology and in addition provide permanent sequestion of at least 25% of the CO produced, it could not be built. This effectively changes the proposed standard from 454 to 499 grams/kilowatt-hour of CO2 emissions in order to construct a new coal fired power plant. The U.S. Energy Information Administration (EIA), however has calculated the construction cost for such technology at $6,599/kW which is signifcantly more costly that the construction of a nuclear power plant at $5,530/kW and not remotely affordable compared to a natural gas power plant at $971/kW. This prohibition, like the historic prohibition of alcohol, is more likely to have negative rather than positive consequences. This paper focuses on facts concerning fossil fuel utilization and its impacts upon global climate, the global economy, and the world population. It contrasts the impacts of current popular notions in the media and the regulations that govern our nation, that fossil fuels are an evil that must be stopped, versus the utilization of common sense to assess how to best use and advance currently available science and technology. It highlights best available control technology (BACT) that could reduce the man made contribution of carbon dioxide in the atmosphere in a way that does not bankrupt the global economy and jeopardize the global population. It will assess the growth of renewable energy and project the number of generations that would be required to have them replace fossil fuel as an energy source. 2015 World of Coal Ash (WOCA) Conference in Nasvhille, TN May 5-7, 2015 http://www.flyash.info/

Environmental Regulation: Recent Experience With Greenhouse Gas BACT Gives Valuable Guidance

AbstractJanuary 1, 2011, marked the beginning of one of the most significant changes to the scope of New Source Review (NSR) rules since their enactment. As a result of greenhouse gases (GHGs) becoming a regulated pollutant under the Clean Air Act (CAA), the Environmental Protection Agency (EPA) determined that such pollutants must now be addressed as a part of Prevention of Significant Deterioration (PSD) reviews. Although no air quality analysis is required for such pollutants, sources must address best available control technology (BACT) for GHG emissions as a part of a complete PSD application.

Emissions from Gas-Fired Agricultural Burners

<abstract> Abstract. Because of the Federal Clean Air Act Amendments of 1990, the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD) began defining Best Available Control Technology (BACT) for NOx emissions from cotton gin drying system gas-fired burners in its jurisdiction. The NOx emission levels of conventionally used, direct-fired burners were unknown, as was how direct-fired burners would compare against newer lo-NOx burners or against the proposed SJVUAPCD NOx emission standard of 60 ppm or less. Replicated laboratory studies were designed to determine the emissions and fuel efficiency of both direct-fired and lo-NOx burner designs. NOx emission levels during the test averaged from 3 ppm for one of the lo-NOx designs to 36 ppm for a direct-fired burner when tested over four firing rates. An economic analysis of the specific cost of NOx reduction achieved by substituting a lo-NOx burner for a direct-fired burner showed an annual capitalized cost of $13,945/tonne ($12,648/T) of NOx reduction. The SJVUAPCD has an upper limit of $10,670/tonne ($9700/T) of NOx reduction to qualify for definition as BACT. Using this economic criterion, lo-NOx burners do not meet the definition of BACT for cotton gins for the SJVUAPCD, and, based upon conferring with industry and environmental specialists, would not for the rest of the United States.

High-solids, low-VOC, solvent-based coatings

This article focuses on the most common high-solids, solvent-based coating technologies. Each of the resin systems discussed is available to meet the Reasonable Available Control Technology (RACT) limits of most state volatile organic compounds (VOCs) regulations. Most systems are also available to satisfy the more stringent regulations of California and the Best Available Control Technology (BACT) requirements of other states. The discussions and tables presented in this article provide sufficient detail to enable a company that is out of compliance with state regulations to make an initial selection of potential coatings that may satisfy the company's performance and production requirements; however, it will still be necessary to ask vendors for samples and to conduct comprehensive production-type tests before implementing the technology of choice.

Regulating greenhouse gases, part II

What a difference a change in administrations makes. Following the November Presidential elections, it was considered a foregone conclusion that the regulation of CO2 and its greenhouse gas (GHG) kin, at least from motor vehicles, was simply a matter of time, in light of the 2007 ruling in Massachusetts et al. vs EPA (549 US 497 [2007]; Front Ecol Environ 5[5]: 279). In that decision, the US Supreme Court found that, “greenhouse gases fit well within the Clean Air Act's [CAA] capacious definition of air pollutant”. The Supreme Court ordered the Environmental Protection Agency (EPA) to determine specifically if emissions of GHGs from new automobiles pose a danger to human health. It is important to remember that the Court did not rule on whether CO2 emissions cause global warming, but on whether scientific uncertainty was a valid reason for the EPA not to regulate a pollutant under the CAA. The Bush Administration sided with the uncertainty argument; the Obama Administration, however, is taking the opposite viewpoint. In November 2008, the EPA Environmental Appeals Board, in In re: Deseret Power Electric Cooperative, reviewed a construction permit for a new waste-coal-fired electrical generation unit in Bonanza, UT. The Board ruled that the EPA had no valid reason for refusing to limit CO2 emissions from new coal-fired power plants. The ruling, practically speaking, suggests that all new and proposed coal plants are required to address their GHG emissions. The most momentous event, however, was held on April 17, when Lisa P Jackson, the new EPA Administrator, signed the Proposed Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 202(a) of the Clean Air Act. Jackson then announced the beginning of a 60-day public comment period, prior to a proposed rule-making, based on a scientific analysis and endangerment finding that would seek to regulate six GHGs – CO2, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride – that pose a potential threat to public health. The announcement was not accompanied by a draft rule seeking to limit GHG emissions directly; rather, the EPA indicated that the comment period was important to an eventual regulatory decision, and that drafting of proposed standards would proceed simultaneously. Notably, the EPA stated that the increasing atmospheric levels of the six GHGs are “the unambiguous result” of human activities and are responsible for more intense heat waves, storms, and wildfires; increased flooding and droughts; and other “effects on public health and welfare”. The document further states, “The heating effect caused by the human-induced buildup of greenhouse gases in the atmosphere is very likely the cause of most of the observed global warming over the last 50 years”. Under Section 202(a) of the CAA, the EPA must decide (1) if GHGs may reasonably be anticipated to endanger public health or welfare, and (2) whether, in the Administrator's judgment, emissions of an air pollutant from new motor vehicles cause or contribute to GHG pollution. If the EPA finds in the affirmative to both questions, standards must be issued. While this proposal deals with cars and trucks, other GHG emission sources can't be far behind. The Obama Administration would prefer the more favorable political course of having Congress pass legislation that would lead to revisions in the CAA through the enactment of a cap-and-trade program. The EPA, it seems, is essentially taking the position that, if Congress doesn't act, they will. So industry can select the proverbial “door #1” and install best-available control technology in areas where GHGs would be regulated as pollutants, or choose “door #2” and introduce some sort of nationwide method of capping GHGs, and allow market forces to dictate a market for such pollutants. Frank O'Donnell, president of Clean Air Watch, described this impending game of “chicken” as: “If business groups, such as the US Chamber of Commerce, continue to oppose Congressional action, they ought to ask themselves…‘Do I feel lucky?' ” Discussion drafts of legislation have already begun to circulate, including the Waxman-Markey American Clean Energy and Security Act of 2009, a complex bill involving carbon control and elimination. So progress is being made, albeit slowly. Profound environmental issues don't usually lend themselves to humor, but we can all hope that a headline that once appeared in The Onion – “Fall cancelled after 3 billion seasons…a beloved classic comes to an end” – will generate future chuckles rather than appreciation for its prescience. And then there is: “How many global warming skeptics does it take to change a light bulb? None. It's too early to say if the light bulb needs changing.”

Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164–7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants—PM 2.5, NO x and formaldehyde—directly emitted by five DG technologies—natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric energy delivered to the place of use. We find that the central tendency of IDER is much greater for almost every DG technology evaluated than for existing CS facilities in California.

The Concepts of Energy, Environment, and Cost for Process Design

The process industries (specifically, energy and chemicals) are characterized by a variety of reactors and reactions to bring about successful process operations. The design of energy-related and chemical processes and their evolution is a complex process that determines the competitiveness of these industries, as well as their environmental impact. Thus, we have developed an Enviro-Energy Concept designed to facilitate sustainable industrial development. The Complete Onion Model represents a complete methodology for chemical process design and illustrates all of the requirements to achieve the best possible design within the accepted environmental standards. Currently, NOx emissions from industrial processes continue to receive maximum attention, therefore the issue problem of NOx emissions from industrial sources such as power stations and nitric acid plants is considered. The Selective Catalytic Reduction (SCR) is one of the most promising and effective commercial technologies. It is considered the Best Available Control Technology (BACT) for NOx reduction. The solution of NOx Emissions problem is either through modifying the chemical process design and/or installing an end-of-pipe technology. The degree of integration between the process design and the installed technology plays a critical role in the capital cost evaluation. Therefore, integrating process units and then optimizing the design has a vital effect on the total cost. Both the environmental regulations and the cost evaluation are the boundary constraints of the optimum solution.

Selective catalytic reduction performance in steam–Methane reformer service: The chromium problem

AbstractSelective catalytic reduction (SCR) performance has been seen to deteriorate with catalyst age at a greater than expected rate in steam–methane reformers (SMRs) and ethylene plants. Loss of catalyst activity has been attributed to deposition of chromium oxide species from alloy furnace tubes and coils on the catalyst surface, thereby masking active catalyst sites. This deposit is visible to the naked eye as a brown or iridescent black discoloration along the passages of a flow‐through honeycomb catalyst, darkest at the entrance face, and gradually becoming lighter as one proceeds downstream. The color becomes more intense with increased exposure to flue gas. It is important for proper design and catalyst‐replacement strategy to understand the governing phenomena at a fundamental level, especially at a time when SCR is increasingly being turned to as best available control technology (BACT), to comply with the more stringent nitrogen oxides (NOx) regulations. This paper describes a correlation of previously unpublished experimental data from catalyst test sections (logs) exposed in the field over a period of several years at multiple SMR plant locations. Consistent with the observed color change, chromium pickup increases with time and varies with operating conditions from plant to plant. Any given log, at any given time, shows an exponential, or semilogarithmic, decrease in chromium concentration over its length. Activity decay of the catalyst has been correlated with the chromium concentration. This single correlation holds true for all of the different plants investigated and can be used to predict remaining catalyst life and optimize future catalyst designs. Scanning electron microscopy (SEM) results and surface analyses from the SCR catalyst and SMR reformer tubes are also discussed, along with suggested countermeasures to mitigate the effects of chromium oxide deposition. © 2004 American Institute of Chemical Engineers Environ Prog, 23: 194–205, 2004

Modeling the Benefits of Power Plant Emission Controls in Massachusetts

Older fossil-fueled power plants provide a significant portion of emissions of criteria air pollutants in the United States, in part because these facilities are not required to meet the same emission standards as new sources under the Clean Air Act. Pending regulations for older power plants need information about any potential public health benefits of emission reductions, which can be estimated by combining emissions information, dispersion modeling, and epidemiologic evidence. In this article, we develop an analytical modeling framework that can evaluate health benefits of emission controls, and we apply our model to two power plants in Massachusetts. Using the CALPUFF atmospheric dispersion model, we estimate that use of Best Available Control Technology (BACT) for NOx and SO2 would lead to maximum annual average secondary particulate matter (PM) concentration reductions of 0.2 μg/m3. When we combine concentration reductions with current health evidence, our central estimate is that the secondary PM reductions from these two power plants would avert 70 deaths per year in a population of 33 million individuals. Although benefit estimates could differ substantially with different interpretations of the health literature, parametric perturbations within CALPUFF and other simple model changes have relatively small impacts from an aggregate risk perspective. While further analysis would be required to reduce uncertainties and expand on our analytical model, our framework can help decision-makers evaluate the magnitude and distribution of benefits under different control scenarios.

Best Available Control Technology (BACT) equivalent for the control of volatile organic emissions from paint dipping operations

This paper provides details of a study conducted to demonstrate an equivalent method of Best Available Control Technology (BACT) compliance for volatile organic emissions from dip coating of certain miscellaneous metal parts. The study was proposed to show that the total volatile organic compound (VOC) emissions from 3.8 lb of VOC/gallon coating formulations were no greater than the total VOC emissions from 3.5 lb/gallon formulations used under the same conditions for coating steel joists. The presumptive BACT standard enforced by the Virginia Department of Environmental Quality (DEQ) for dip coating of steel joists is 3.5 lb/gallon. The requirement of 3.5 lb/gallon was derived from the US Environmental Protection Agency Guideline Series Control of Volatile Organic Emissions from Existing Stationary Sources--Volume 6: Surface Coating of Miscellaneous Metal Parts and Products. On June 5, 1998 the source completed a 12 month, full scale comparison study under a consent order with the Virginia DEQ. During the study period, the source made daily measurements of product produced, paint used, and emissions from the control and test paint tanks, and reported data to EPA and the DEQ every two months. The study concluded that a 26 percent reduction in paint usage and a 20 percentmore » reduction in emissions was achieved in the test tanks using a 3.8 lb/gal coating compared to the control tanks using a 3.5 lb/gal coating. This study enables the source to achieve greater emission reductions than the presumptive BACT level and at the same time reduce painting costs by 34%. This study provides positive results for the environment, the steel joist industry, and the construction industry. This study could impact EPA's current Maximum Achievable Control Technology (MACT) rule development for Miscellaneous Metal Parts and Products and national VOC rules for this source category under Section 183(e) of the Clean Air Act.« less

Estimating cost effectiveness of residential yard trees for improving air quality in Sacramento, California, using existing models

The Sacramento Municipal Utility District's (SMUD) shade tree program will result in the planting of 500,000 trees and has been found to produce net benefits from air conditioning savings. In this study we assume three scenarios (base, highest, and lowest benefits) based on the SMUD program and apply Best Available Control Technology (BACT) cost analysis to determine if shade trees planted in residential yards can be a cost effective means to improve air quality. Planting and maintenance costs, pollutant deposition, and biogenic hydrocarbon emissions are estimated annually for 30 years with existing deterministic models. For the base case, the average annual dollar benefit of pollutant uptake was $895 and the cost of biogenic hydrocarbon emissions was $512, for a net pollutant uptake benefit of $383 per 100 trees planted. The uniform annual payment necessary to repay planting and maintenance costs with a 10% rate of interest was $749. When high biogenic hydrocarbon emitting tree species were replaced with low-emitters, the base case benefit-cost ratio (BCR) increased from 0.5: 1 to 0.9: l. The BCR for the “highest” and “lowest” benefit cases were 2.2:1 and −0.8:1, respectively. Although SMUD plantings produce cost effective energy savings, our application of the BACT analysis does not suggest convincing evidence that there is cost savings when only air quality benefits are considered.

Estimating physical properties for control equipment design

AbstractThere is a great deal of information about physical properties available to engineers. The trick is in knowing where to find what is needed when it is needed. Many of the widely available sources lack information that is needed for process design. Material Safety Data Sheets (MSDSs) include relatively little physical properties data and no transport properties. Standard references like Perry's Chemical Engineer's Handbook, the CRC Handbook of Chemistry and Physics, and Lange's Handbook of Chemistry may not have data for a particular property or compound.The handbooks have information about hydrocarbons, and some of the common industrial alcohols, ketones, and esters. Data on some common industrial solvents, such as the glycol ethers and their acetates, is rather sketchy in the classic manuals. What can an engineer do if there is a need for data not available in the common references?For example, USEPA published several guidance manuals that present cost estimating techniques for air pollution control equipment. Engineers working in industry and for regulatory agencies apply the guidance in these manuals in trying to determine whether any of several control options represent the Best Available Control Technology (BACT) for an emissions source. BACT is the maximum level of control, considering economic factors as well as pollutant removal.Even the simplified design procedures in USEPA's Control Technology for Hazardous Air Pollutants require information that is just not found on an MSDS. Incinerator operating cost estimates depend on the heat available from the pollutants, the heat of combustion. The sizing and cost estimating procedure for refrigerated condensers calls for vapor pressure data, the heat of vaporization, and the heat capacity (specific heat). A cost estimate for an absorption system to scrub air pollutants demands vapor‐liquid equilibrium information, diffusivities, and the pollutant molar volume.Instead of starting a game of phone tag with the vendor's customer service department or spending several hundred dollars for a reference book you may not need again for five years, why not try estimating techniques for physical properties? These techniques have been around for a long time and offer reasonable accuracy within their limits. Estimated values are certainly accurate enough for budgetary‐quote‐level design procedures.More accurate estimating techniques are available [3]. The drawback to more sophisticated methods is increased complexity. Often, the more precise estimate calls for a multi‐step calculation, with several adjustable parameters. The methods described here are fairly simple, either empirical formulas or group contribution schemes.

Health impact of a proposed waste-to-energy facility in Illinois.

The Illinois Environmental Protection Agency (IEPA) has given the Robbins Resource Recovery Company (RRRC) a permit to construct a Regional Pollution Control Facility in Robbins, Illinois. Site approval for this waste-to-energy (WTE) combustor has been granted by the Village of Robbins which is located about three miles south of Chicago. The facility is designed to operate continuously for 40-45 years, process 1600 tons of municipal solid waste (MSW) per day, and produce over 50 megawatts of electricity. Refuse derived fuel (RDF) will constitute essentially 100% of the operating fuel. The fuel preparation system is designed to recover 25% (by weight) of the MSW in the form of recyclable materials (ferrous, aluminum cans, glass, and compostables). Also, appliances, electronic equipment, household batteries, and lead-acid vehicle batteries will be removed. The air pollution control system for the two circulating fluidized bed combustors has been characterized by the USEPA and the IEPA as Best Available Control Technology (BACT) based on the following components: selective non-catalytic reduction (SNCR) to control nitrogen oxide emissions and dry flue gas scrubber (spray dryer absorber) and fabric filter baghouse to control emissions of acid gases (mainly hydrogen chloride and sulfur dioxide), particulates, and metals. In addition, activated carbonmore » injection will be used to control mercury emissions (RRRC, 1992). 10 refs., 3 tabs.« less

Activated carbon injection in spray dryer/ESP/FF for mercury and toxics control

In the last decade, dry scrubbing by spray dryer absorption (SDA) has been applied to more than 17 000 MW of coal-fired boilers, and several hundred municipal solid waste (MSW) and hazardous waste plants. In the MSW application, process development for air toxic control has advanced to a point where a spray dryer absorber, followed by a fabric filter, has been determined to be the best available control technology (BACT) in several countries throughout the world. Extremely high removal of dioxins and furans, as well as mercury and other trace toxics, is now state of the art in this application. The paper describes the recent development in the air toxics removal capability of dry scrubbing for coal-fired utility plants. Results of a study characterizing the inherent mercury removal efficiency of full-scale dry scrubbers in Europe and the United States are presented, as well as results of activated carbon injection tests performed at one full-scale installation. The paper further reports results of two pilot plant research programs. One pilot plant was equipped with an electrostatic precipitator, the other pilot plant with a baghouse. The paper reports results of activated carbon injection and identifies the parameters and conditions important for achieving high mercury removal in a dry FGD system. Options for control of mercury on eastern and western US coals are suggested. Results of mercury speciation are also given. Removal results of other vapor phase toxic trace metals, such as boron and selenium, are presented. Finally, the paper makes reference to the results of two mercury revolatilization studies.

Novel particulate control device for industrial gas cleaning

An innovative concept in particulate control has been developed for industrial gas cleaning. The Core Separator is believed to be one of the few major advances within the field of particulate control in many years. Its performance is very good, almost as good as the most efficient ESPs and fabric filters, but without the attendant cost and maintenance. In certain applications, it may be the Best Available Control Technology (BACT).

"Fuel Cleaning" and Materials Separation at Waste-to-Energy Plants

Separation of materials from municipal waste streams is not recycling. Successful recycling is demand-pulled rather than supply-driven; it depends on local markets that reuse separated materials. For this reason EPA's Office of Solid Waste has opposed national mandates for materials separation which do not address associated markets. But a recent Air Act decision could reverse that stance, potentially mandating high levels of materials separation for every new waste-to-energy (WTE) facility. The decision holds that Best Available Control Technology (BACT) requires PSD permit applicants to consider separating "feasible" levels, of each "readily-ascertainable" waste component that contributes to air emissions when incinerated, despite their installation of advanced emissions controls or the lack of any evidence that emission concentrations would be further reduced by such "fuel cleaning." Because total emissions of any facility may always be reduced by requiring it to consume less fuel—or burn gas rather than oil, or use conservation rather than combust at all—the decision could radicalize New Source Review, transforming preconstruction permits from a process meant to assure specific emissions controls to one in which air agencies deny the existence of emitting sources. The decision could also delay preconstruction permits; force downsizing of disposal facilities EPA concedes to be necessary; accelerate landfill closures; inject air permit writers into solid waste management determinations; and make local waste infrastructure more difficult to finance. It demonstrates the slippery slopes created by attempts to convert single-medium statutes into multi-media programs under the banner of "pollution prevention."