Impact of regulations on coal conversion plants Existing and foreseeable regulatory policies are examined in light of their possible effects on the design, siting and economics of new coal conversion plants Coal conversion plants will soon be part of the fuel technology of the U.S., transforming our most abundant, but environmentally unacceptable fuel, into clean synthetic gases and liquids (Table 1). Commercial utilization of these low-sulfur, low-ash fuels will thus maintain environmental quality while contributing to energy self-sufficiency. However, the environmental impacts of coal conversion plants are potentially quite sizeable. In order to avoid simply transferring the environmental impacts of coal utilization from existing facilities to these new technologies, an early and careful assessment of the environmental aspects of coal conversion processes is required. Environmental control measures occur within a regulatory framework established by federal, state, and local agencies charged with defining and implementing environmental control policy. Recent environmental regulatory activities in air and water pollution control are likely to also affect new coal conversion processes; some implications of these activities on process requirements and environmental impacts are examined in this article.
combustion, is often required for the operation of pollution control systems on plant process streams (either directly or via electric power production), combustion-generated pollution at a plant results, in part, from the need for other environmental control measures. In this light, tradeoffs among different pollutants and environmental media become apparent. Among potential air pollutants, sulfur dioxide is emitted from the tailgas stream of the process sulfur recovery plant, and from stack gases of auxiliary combustion systems. The latter includes coal pretreatment processing, plant boilerhouse, and miscellaneous process heaters and burners fired with sulfur-bearing fuels. Particulate matter can enter the atmosphere as a fugitive dust, or as a stack emission from combustion or pro1 A B L E 2.
Types and sources of potentia pollutants from coal ~ ~ n v ~ pr r~ io ~ c m~ ~ ~ ~ P?'QCeSS- Combus-
Pollutant
Sources of pollutants Tables 2 and 3 indicate the major air and water pollutants known or suspected to be associated with coal gasification or liquefaction processes. Table 2 indicates the air pollutants originating from the coal conversion process and from fuel combustion. The latter includes both on-site auxiliary combustion required for the process, and end-use combustion of the synthetic fuel products themselves. Since boilerhouse steam, raised on site by direct TABLE 1.
Typical coal conversion processes under development Name
High-Btu Gasification 61-GAS COGAS CO? acceptor HYGAS Lurgi Molten salt Syntha n e Low-Btu Gasification Agglomerating gasifier Atgas Entrained gasifier Koppers-Totzek Lurgi Stirred fJXed b e d Liquefaction Catalytic coal Irquid COED Hydrogen donor Project gasoline Solvent refined coal Turbulent catalytic 112
Developer/Spansor
BCRIOCR-AGA FMC Corp. Consol/OCR-AGA IGTIOCR-AGA L u rgi M .W. Kel logg BuMines
Westinghouse/OCR-Private AT1/EPA CEiOCR Koppers Lurgi 5uMines Gulf FMCjCrCR Exxon Conoco P&M /So. Svcsj'OCR 5uMines
Environmental Science & Technology
Particulate matter Suifur oxides Reduced sulfur compounds Nitrogen oxides Hyd rocar bons Carbon monoxide Trace metals Other gases (rncl. N H < ?HCN, HCI, odorants)
gen-
erated
tion-genet
ate$
x
X
x I:
x "c
r:
'i
Y
%"
x
x
K.
cess unit operations. Fugitive emissions are most likely to occur at receiving, handling and storage areas for coal, solid wastes, or solid products. Stack emissions occur at the exhaust streams of gas cleaning devices on unit operations such as coal driers, pulverizers and.gasifiers. Emissions of nitrogen oxides in the plant result from fuel combustion in boilers and process heaters. End-use combustion of the synthetic fuel also releases NO,. Emission levels depend on the fuel type, boiler design, combustion parameters, and fuel nitrogen content. Emission of hydrocarbons occurs by evaporation from liquid product storage areas, from leakage at valves, flanges and seals, and from evaporation of hydrocarbon liquid dissolved in liquid waste or cooling streams. Incomplete combustion at auxiliary plant facilities also releases hydrocarbons, as well as carbon monoxide (CO). CO is also a prime fuel constituent produced in large quantities in coal gasification processes. Its release to the atmosphere, however, occurs principally from incomplete corn bust ion. Reduced sulfur compounds (H2S, COS, and CS2) occur in the initial gas stream of virtually all coal conver-
E. S. Rubin and F. C. McMichael Carnegie-Mellon University
Pittsburgh, Pa. 75273
sion processes. Their release to the atmosphere is due to: incomplete stripping of the process exhaust streams in which they are found (C02, sulfur recovery tailgas); evaporation from scrubbing water at cooling towers; and formation during quenching of sulfur-bearing process residues or slags. Other gaseous emissions, including hydrogen cyanide, ammonia, hydrogen chloride, and gas odorants may also occur by evaporation from cooling or scrubbing liquors in which they are dissolved. Trace element emissions of heavy metals, which are contained in coal in small amounts, may also occur via vaporization during combustion or coal refining. Wastewaters from coal conversion processes originate from: e moisture in the coal, e water of constitution or decomposition, e water added for stoichiometric process requirements, e water introduced for by-product recovery or gas scrubbing. These process waters come into direct contact with contaminants in coal, and are thus the principal source of pollution, rather than non-process waters used only for indirect cooling. Virtually all coal conversion processes, however, are net consumers of water (the principal source of hydrogen required for the process chemistry), so that ideally, all streams could be recycled for use in the process. The reason effluent streams do occur is that in practice it is often technically or economically infeasible to recycle all wastewaters consumptively, and to control all stream flows to yield the stoichiometric water requirement. Because water is a universal solvent, the composition of process waters from coal is complex. In many ways, coal process waters have an inorganic composition as saline as seawater with the addition of small amounts of practically all the organic compounds found in coal. Any condensate water is thus expected to have a composition similar to those shown in Table 3. The similarity in that table between contaminants in waste ammonia liquor (a major wastewater stream from the by-product coking industry) and those reported for the BuMines Synthane Process by-product waters further suggests the complexity as well as the possible composition of coal conversion plant waste effluent.
U.S. policies Regulatory policies for air and water pollution control fall into two general categories: standards defining acceptable levels of environmental quality; and standards limiting the discharge of specified substances to the environment. The former typically specify the concentration of a pollutant in the environment that is not to be exceeded; the latter generally specify a maximum allowable dis-
TABLE 3.
Composition of wastewaters representative of coal conversion urocess waters Coke Plant Waste ammonia liquor (mglliter)
PDllYtant
PH COD Ammonia Cyanide Thiocyanate Phenols Sulfide Alkalinity (as CaCOs) Specific conductance (asrmho/cm) a
8.3-9.1 2.500-10,000
Synthane process byproduct water (mgtliter)
7.9-9.3 1,700-43.000
1,800-4.300 10-37
2,500-11.000
100-1,500 410-2,400 040 1,200-2.700 11,000-32,000
21-200 200-6,600
0.1-0.6
N/Da NJD N/D
Not determined
cnarge rate analor concenrrarion, or require speciric types of control equipment or system design that limits' pollutant release. The two types of standards may or may not be related to, or consistent with, one anothei. For example, while air quality standards have provided the quantitative basis for many emission regulations throughout the country, water pollutant effluent regulations are presently formulated mainly on the basis of technological capability, rather than from considerations of the control levels required to achieve water quality standards. Environmental quality standards Standards of environmental quality for air and water are established by a.combination of local, state, and federal authorities. For air, the 1970 Clean Air Act Amendments mandate the federal government, through the Environmental Protection Agency (EPA), to promulgate ambient air quality standards that apply nationwide. In turn, emission control strategies are to be designed by each state to achieve primary standards by mid-1975, and secondary standards as soon as possible thereafter. Individual states may promulgate air quality standards more stringent than national standards, and indeed, many states have done so. Federal responsibility also includes preventing "significant deterioration" of existing air quality. Regulations recently promulgated by the EPA would permit the "significance" of air quality deterioration to be weighed against social and economic considerations by establishing three area classifications. Each would be subject to a different increment of allowable air quality deterioration, permitting concentrated, modest, or no additional industrial development. Primary responsibility. for classifying all areas would lie with the states. The Federal Water Pollution Control Act Amendments Volume 9, Number 2. February 1975
113
of 1972 require each state, with the approval of EPA, to establish receiving water quality standards for its waterways that protect fish life and recreational use. In addition, there is a strong emphasis on effluent limitations and source permits apart from water quality standards. General water quality criteria designed to protect the water uses of streams typically refer to the elimination of floating solids, films and scums, bottom deposits, and objectionable odors. Additionally, most states set limits on specific wastewater parameters such as pH, temperature, dissolved oxygen, phenol, ammonia, and cyanide. However, these may be set at different limits on the same river by different states; for example, the phenol limits for West Virginia and Pennsylvania differ by a factor of five, and the cyanide limits for Ohio and West Virginia by a factor of ten. Other special types of environmental quality standards are the U.S. Public Health Service drinking water standards and threshold limit value (TLV) occupational health standards for air pollutants. These affect only selected populations, not the public at large. Pollutant discharge standards Regulatory policies restricting the discharges of pollutants to the environment are established by federal, state, and local agencies. At the federal level, air and water pollutants are subject to New Source Performance Standards (NSPS), which affect newly constructed or substantially modified processes or unit operations. These standards, promulgated by the EPA, call for the use of "best adequately demonstrated technology." Specification of NSPS emission or effluent limitation levels is thus divorced from any consideration of environmental quality impacts. For existing sources, federal standards for water pollutants further require installation of "best pollution control technology currently available" by mid-1977, and "best available technology economically achievable" (BATEA) by mid-1983. Additionally, there is a congressionally-mandated "zero discharge" provision of the 1972 Water Act with the goal of eliminating the discharge of pollutants into navigable water by 1985. Federal performance standards will generally impose the most stringent limitations on allowable release of pollutants to the environment. While such standards do not yet exist for coal conversion processes, wastewater standards have been promulgated for two related processes
Wastewater effluent limitations for coal conversion processes might parallel those for petroleum refineries and by-product coking XY-
Petroleum refineries (lb~l000b b l feedstock)
Pollutant
5 - d a y biochemical o x y g e ~ demand (BOD5) T o t a l s u s p e n d e d solid5 (TSS)
product coking
( I b 1000 I b coke)
M a x i m u m 30-day a v e i a g e
% a
I ?F;-IR.SS ;I
Chemical cxygen cierrisrld
N
oiri.1 A
(COD)
Oil arid grease Phenolics Ammonia ( a s N) Sulfide
Total chromium H e x a v a l e n t c hrorrii u m p h (for a l l categories) Cyanides amenable t o c t i lori ria ti on
(1. L3-5. YO
O.2d-11.0L
i!.
O.OOi3--0.1015 0,w26--0,30.i5 0,00038g . 005'
0.
6.0--9.0
60
N A
o ooni y '
I
114
Environmental Science & Technology
rd
CI
N A ?.(I
-petroleum refineries and coal carbonization plants (Table 4 ) . Federal air standards for refineries and steam generators (Table 5 ) are also relevant to coal conversion. Emission and effluent limitations not covered by federal performance standards are established by state and local agencies. These limitations are subject to EPA approval, except for regulations that are more stringent than federal standards, in which case the local regulation takes precedence. For example, many states have adopted regulations for sulfur dioxide emissions from fossilfuel-fired steam generators that are more stringent than the federal NSPS. This policy could directly affect emission requirements for auxiliary boilers of coal conversion plants. Sulfur recovery plants are another process category important to coal conversion facilities. Here, the majority of states with a recovery plant standard have adopted an SO2 emission limitation of 0.01 Ib S02/lb S input, corresponding to 99.5% control of potential sulfur dioxide emissions. This is also the value suggested by EPA in its 1971 guidelines for state implementation plans. A federal NSPS, however, is forthcoming. At present, the most comprehensive state air pollution regulations directed specifically at coal conversion processing are those recently adopted by New Mexico in anticipation of two Lurgi-based gasification plants scheduled for construction. These are shown in Table 5. For water pollutants, state and local effluent standards are generally not as stringent as federal effluent guidelines, but there are some exceptions. Until such time as federal performance standards for coal conversion plants are formulated, state and local standards of the types indicated above will determine allowable effluent limitations for plant wastewaters. Implications of standards Some insight into possible wastewater effluent standards for coal conversion processes is possible from an examination of current standards for by-product coking and petroleum refining. The two sets of standards may be compared on an equivalent basis by expressing them in terms of the energy input of process feedstock. Such a comparison is shown in Table 6. On this basis, all coke industry effluent limits fall within the range of petroleum refinery limits for pollutants common to both industries. While this comparison may be fortuitous, it may also suggest an estimate of potential effluent limitations for future coal conversion processes. Importantly, however, refinery standards vary with plant size and complexity, and specify "end-of-pipe'' limits, neither of which applies to coke plants in integrated steelmaking. The basis for future coal conversion standards, therefore, is unclear. Moreover, the fact that coal refineries are net consumers of water increases the potential for zero discharge regulations. This could 'cause coal conversion standards to be quite different from the cases examined here. Of the several existing new source performance standards for air pollutants, those for fossil-fuel-fired steam genarators have the clearest implications for coal conversion processes, since many require a large on-site boiler plant nominally fired by coal or char. Often, however, the sulfur content of solid fuels currently designated for these boilerhouses exceeds the federal NSPS. One implication of present regulations, therefore, is that boiler plants utilizing such fuels may be required to remove sulfur by: stack-gas cleaning, coal or char pretreatment, fluidized bed combustion, or conversion of the solid fuel to a lowBtu gas. Further study is needed to evaluate the technology and economics of these alternatives, including their use relative to other possib es such as the substitution of cleaner fuels. Existing NSPS for steam generators also do not yet include an S O n limitation for combustion of a gaseous fuel,
such as an H2S-laden low-Btu gas-a prominent class of coal-derived fuel. While the EPA has indicated that such a standard will be forthcoming in 1975, regulations already promulgated for low-Btu gas (plant gas) combustion at petroleum refineries (Table 5) point toward a future standard that is nearly ten times more stringent than existing new source standards for non-gaseous fossil fuel combustion. This is also reflected in the New Mexico standard for gas-fired boilers (Table 5 ) . Nonetheless, some low-Btu gas processes for boiler fuel are today being designed and developed to comply only with the existing SO2 standards for solid and liquid fuels. Clearly, the design, economics and competitiveness of such processes may well be affected by foreseeable future environmental regulations. Other existing NSPS for fossil fuel steam generators will also affect coal conversion facilities. For nitrogen oxides, little data are currently available on the NO, characteristics from combustion of chars and synthetic liquid fuels. While various combustion modifications have successfully reduced NO, emissions from boilers fired with conventional fossil fuels, the precise implications of the NSPS on combustion of coal-derived fuels will have to await full-scale demonstration tests. While existing technologies such as scrubbers, precipitators, and fabric filters may provide adequate control of particulate emissions, particulate collection from boilers fired with synthetic liquids or low-sulfur chars also remains to be demonstrated before the implications of new source steam generator standards can be fully assessed. For process operations, new source particulate standards promulgated to date typically limit emissions to control levels in excess of 99% relative to the uncontrolled process, and similar levels are thus likely for coal refineries.
further degraded because of the incremental fuel consumption needed at the boilerhouse to produce the steam and power needed to control air and water process emissions. Figure 1 illustrates this for a coal refinery. Combined SO2 emissions of the sulfur recovery tailgas, plus that portion of boilerhouse SO2 emissions resulting from onsite steam generation for process gas desulfurization are shown. Sulfur recovery efficiency is assumed to be 99.5%, the current level of many state standards, while boilerhouse energy requirements are taken over the range reported for several prclcesses desulfurizing coke oven gas. For the assumptions in this example, a purification system requiring 5 Ib steam/lb S would cause an incremental SO2 boiler emission comparable in magnitude to the emission at the tailgas stack. Alternatively, the effective process desulfurization efficiency decreases
Secondary environmental impacts Environmental impacts from coal conversion include secondary as well as primary impacts. One example of this arises from utility requirements for gas-cleaning and effluent treatment systems. Here, the air environment is Volume 9, Number 2, February 1975
115
by 0.07% for each Ib steam/lb S when auxiliary energy requirements are taken into account. Tradeoffs are thus found among pollutants discharged to one or more environmental media. Many of these are well known, such as the solid waste disposal problems that can result from preventing SO2 release to the atmosphere by stack-gas scrubbing. Often, however, such tradeoffs are difficult to acknowledge in regulatory policy, both because of existing institutional structures (separate air and water authorities) and the inherent difficulty in comparing the significance of different discharges to different media. Less understandably, existing regulatory policies with respect to emission standards also appear to discourage tradeoffs or incentives that minimize the impact of a single pollutant discharged to a single medium. This question of intra-media tradeoffs could arise in the example above 'since, for many processes, energy requirements for gas desulfurization increase exponentially with increasing removal efficiency. Thus, one can envision cases in which regulations to reduce process sulfur emissions actually worsen the overall situation because of off-setting increases in boilerhouse SO2 emissions. Current regulatory policies focused only at individual unit operations could prove counterproductive to environmental quality if secondary impacts are not considered. I nter-agency jurisdiction Present institutional arrangements for implementing environmental regulatory policies call for a sharing of responsibilities among federal, state, and local agencies, which are often charged with only a single area of environmental concern. A case study perhaps best illustrates the potential implications of such an arrangement for coal conversion processes. The largest by-product coke manufacturing facility in the world is the U.S. Steel Clairton facility in Allegheny County, Pennsylvania. The plant processes about 30,000 tons of coal per day, substantially more than presently proposed for most commercial-scale coal conversion plants. For many years the Clairton plant operated with zero discharge of a major process wastewater stream by using it to quench hot coke. This practice achieved compliance with Pennsylvania regulations stringently limiting effluent dissolved solids content, and prohibiting measurable discharges of phenols, cyanides, or ammonia to waters of the Commonwealth. In 1970, however, Allegheny County independently enacted a regulation to control air pollution by prohibiting the quenching of coke with water not suitable for discharge to the nearest stream. The result of these regulatory constraints on air and water was to force a major change in plant operating practice ( f S & T , December 1974, p 1062), in which the company entered into a consent decree to develop and install a modern wastewater treatFig I
P
rlant
1.5%
Sulfur input to recovery plant (tpd) 116
Environmental Science & Technology
ment system for its plant effluents in return for a relaxation of the Pennsylvania water standards. Such a case strongly underscores the need for an early and thorough assessment of process environmental impacts in order to minimize or avoid future problems. Indeed, the early and coordinated involvement among local, state, and federal regulatory authorities is essential for the efficient implementation of environmental regulatory policies. Air quality impacts The implications of current national and state ambient air standards on coal conversion processes go directly to questions of plant siting. It becomes necessary to consider all regional sources of air pollution, and the way in which they interact with the coal conversion plant to affect the ambient air quality at any location. This involves concern for the geographical distribution of sources, their pollutant mass emission rates, discharge stack heights, process parameters, local or regional meteorology, and atmospheric transport processes. Even where there is ready compliance with all applicable emission standards, the added constraint of air quality standards can profoundly restrict the design flexibility and siting of a particular facility. For example, with existing state regulations for sulfur recovery plants requiring a 99.5% control efficiency, a plant processing 20,000 tpd of 4 % sulfur eastern coal could emit up to 8 tpd of SO>, while the same plant operating on a 2% sulfur coal seam would emit no more than 4 tpd. Both conditions would comply with the applicable SO2 emission standard, but the former could result in up to a twofold degradation of air quality relative to the latter. Estimates of the ambient concentrations resulting from specified pollutant mass emission rates are often obtained with diffusion modeling techniques. Figure 2 shows isopleths of annual average ground-level SO2 concentration predicted by the Air Quality Display Model for a hypothetical 20,000 tpd conversion plant located in western Pennsylvania, processing 2.6% sulfur coal, and containing two SO2 sources in compliance with current emission regulations. In this illustration, the maximum annual average SO2 concentration, owing to the conversion plant alone, is 16 pg/m3, of which 66% is due to the boilerhouse. Lower concentrations would result with taller stacks, dispersed sources, increased gas desulfurization, lower sulfur coals, or a smaller plant size. In terms of environmental policy implications on coal conversion processes, non-degradation regulations recently promulgated by EPA include a limit on the total future change in annual average SO2 concentration of 2 p g / m 3 in areas designated for highly restricted development (Class I ) , 15 ,ug/m3 in areas of modest development (Class I I ) , and up to national ambient standards in areas of concentrated development (Class I l l ) . Thus, a coal conversion plant with air quality impacts at the levels shown in Figure 2 could probably be sited only in a Class I I I area. Even here, site acceptability would further depend on how significantly nearby and background sources influence local air quality. While technological remedies such as taller stacks and/or additional effluent desulfurization can increase the flexibility for plant siting, they also add to the plant costs. The non-degradation issue will likely pose one of the critical constraints on the economics, design and siting of coal conversion fac Water quality impacts Mathematical models for predicting water quality impacts are typically restricted to substances such as chloride, dissolved oxygen, and municipal waste BOD. The fate of substances such as phenol, cyanide, and ammonia are not routinely modeled, nor are source-receptor relationships developed.
oncentration
Fig 2
I.g/m'f for a hypothetical 20,000 tpd coal conversion plant AUXIIIBV 8oders Comply with solid fuel NSPS
(12 Ib S0,ilO' Biul Ftred at 30W mtlilon Btuihr Total S0,emisslon = 43 tpd Effective stack height = 6Wft Sulfnr Recovery Plant Processes5w tpd sulfur operates at 595% efficmcy Tailgas SO,ernis~~an= 5tpd Effective stack height = 300 ft
Local CilmatologY Southwest Pennsylvania, 7-year a"n"ai average stability wind rose
F()r present purposes, therefore, the potential irnpact of C8oal conversion plant wastewaters on receiving water quai ity is characterized in terms of the quantity of plant -"+* .^l^+i..n +?. ,.the. ..aoLI..aLII e n , , " l l P C in c efflur,,La IrlaLllr ,,, , given region or watershed, where detrimental impacts are concentrated. The region selected for illustration includes six eastern coal states primarily .affecting the wateished of the Ohio River (Figure 3). These states also hold more than one-fifth of the U S . petroleum refinery crude capacity, as well as s!ightly less than two-thirds of the country's by-product coke capacity. Total regional burden of selected pollutants are estimated for a situation in which six 20,000 tpd co.al conversion plants are assumed to be adtled to the region (an average of one per state), each complying with the federal BATEA effluent limitations for by-product coking. Existing coke Dlants and refineries are similariv assumed to be in comIpiiance with their respective BATEA effluent l i niitation!>. Under these conditions, the effluents from the six coal conversion plants are comparable in magnitude to the
."
I.,~r'n..,~+a,
total allowable waste load for ali existing coke plants in the region, and also represent a sizeable fraction of wastewater from all existing regional refineries. Even this relatively simple type of comparison thus provides an important perspective as to the potentially significant regional implications of future coal conversion facilities. Policy research questions In addition to the need for carefully assessing individual coal process impacts-which include many problems besides air and water-several bioader questions deserve careful study in the development of coal conversion regulatory policies: a How should plant size, complexity and product mix enter the reguiatory picture? Can incentives be structured so as to reward process efficiencies that reduce environmental impact? a For a given medium, should pollutant discharges be limited for individual processes or unit operations, or for larger systems including the total plant? How can regulatory policies accommodate tradeoffs among different process~elements? a To what extent is it possible to implement a multimedia (air, water, land, etc.) approach to environmental control that minimizes total environmental impact? How do you evaluate cross-media tradeoffs? a Can the existing regulatory structure be modified to streamline policy formulation and avoid or minimize jurisdictional conflicts? Clearly, these questions are by no means unique to coal conversion processes. What makes them especially relevant to coal conversion, however, is that we are speaking here not only of a potentially large-scale industry.with significant environmental impacts, but one which, by virtue Of its newness, is in a relativelv aood Dosition to respim d to productive policy innovations that more effectivel)t minimize environmental impacts. Governmental polic y-makers must similarly respond with leadership and foresLight to ensure the efficient development of new energy technologies that are compatible with high standard:s of environmental quality. Addltional reading Procf?edings . -of . Symposium . _ _ .on..Environmental . - - . . . . . . Aspects - - - . of...Fuel . Convers,on iecnnoiogy, tPA-650/2-74-1lU. U.S.t.P.A., wasnington, D.C., November 1974. Gouse. S. W., and Rubin. E. S., "A Program of Research, Development and Demonstration for Enhancing Coal Utilization to Meet National Energy Needs," CMU/NSF-RANN Workshop on Advanced Coal Technology, NTlS Report No. PB-226-631, October 1973. Magee, E. M.. Jahnig. C. E., and Shaw, H., "Evaluation of Pollution Control in Fossil Fuel Conversion Processes, Gasification; Section 1: Koppers-Totzek Process." EPA-650/2-74-009a. U.S.E.P.A., Washington, D.C.. Jaduary1974 Massey, M. J., and Dunlap. R. W., "Economics and Alternatives for Sulfur Removal from Coke Oven Gas." Paper .NO. 74-184. 67th Annual Meeting, Air Pollution Control Assn., Denver, Colo., June9-13,1974 I
Edward S. Rubin is associate professo,r of Mechanical Engineering and P U 4lic Affairs at Carnegie-Meiion UCriversity. Dr. Rubiri's educational, co nsuifing and research interests ha ve been in the areas of environmc?ntalcontrol, and energy utilization.
Estimated total regional wastewater effluents under compliance with current regulations
Phenolics
25500
40
33
Ammonia
1,40&55,000
830
1w
SuspendedSolids
6,000-80,OW
2,ow ...
~
....
.
.
..
University. Dr. McMichael's" research interests are primarily in the area of
1.100
.
.
,:
.
Coordinated by LRE Volume 9, Number 2, February 1975 117
