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CIRCLE 13
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Coal conversion retort Dear Sir: We would like to thank Mr. Beychok for his useful and informative discussion ( E S T , May 1975, p 396). We certainly find no disagreement with him that our recent €S& T feature article “might be misleading when applied to a specific process and to specific plant locations.” Indeed, we believe that any application of this sort would reflect a serious misuse and misunderstanding of our remarks. Our intent was to provide an overview of current environmental regulatory policy for air and water pollution control in the U.S.,and to discuss, in a general fashion, some implications of these activities for coal conversion processes (of all types) being developed in the U.S. today. If our discussion of SO2 emissions and air quality impacts based on the new source performance standard and a hypothetical eastern plant created the impression that those figures could be readily applied to any specific process and location, such as a Lurgi gasifier in New Mexico, we are deeply indebted to Mr. Beychok for a chance to clarify this issue. Indeed, we specifically indicated in the article that, “many states have adopted regulations for sulfur dioxide that are more stringent than the federal NSPS;” that, “the added constraint of air quality standards [and non-degradation standards] can profoundly restrict the design flexibility” (including emission requirements) of a particular facility; and that even for our hypothetical eastern plant complying strictly with the NSPS, the air quality levels illustrated would be lower “with taller stacks, dispersed sources, increased gas desulfurization, lower sulfur coals or a smaller plant size.” We would hope, then, that readers would be dissuaded from applying our discussion to specific processes, and certainly, to specific plant locations. Our principal reason for using the NSPS as a basis for illustration is that it does represent established national policy, and is in fact also the most stringent emission limitation currently applicable in most (though certainly not all) states, including many western states. This is true even for several states other than New Mexico, for which Mr. Beychok indicated Lurgi gasification projects are underway: Current SO2 Emission Limitations for Coal-Fired Boilers (Ib S02/106 Btu) Federal NSPS 1.2 New Mexico 0.34 North Dakota 3.0 Montana 2.0
Wyoming Illinois
0.2” 1.2
No regulation prior to Feb. 26, 1975. Thus, while other western states may in the future follow the lead of New Mexico and others as Mr. Beychok suggests, this has yet to be universally incorporated into established public policy. In the same sense, we have no trouble acknowledging that refrigeration of Lurgi process gases may be an acceptable technology for preventing emissions of cyanides, ammonia and hydrogen chloride to the atmosphere. Nonetheless, they do represent “potential” air pollutants for coal conversion processes before control, which is all we attempted to indicate. Some much more fundamental issues, however, are raised by Mr. Beychok’s feeling that we failed to stress what he sees as the basic weakness of EPA’s NSPS for coal-fired boilers-Le., that the single standard may require no additional SO2 removal for sufficiently low sulfur coals, even though the technology to reduce emissions may be available. It is not all apparent to us that a public policy of this type-one that focuses on a specific unit operation and requires that emissions of a given pollutant in all cases be reduced to the lowest levels achieveable-is necessarily optimal or desireable. Rather, we believe strongly that the TANSTAAFL principle (“There Ain’t No Such Thing As A Free Lunch”) is always at work, and that questions as to the ”leniency” or “stringency” of a regulation or set of regulations can only be appropriately considered in the context of a broader treatment that attempts to recognize all of the costs and all of the benefits that pertain. As we attempted to illustrate in our article, this involves consideration of the levels of pollutants that will be allowed to enter different environmental media (air, water, land), and of the tradeoffs inherent in controlling emissions of different pollutants to different media from different unit operation of a complex industrial facility. Certainly, we do not represent this to be an easy task. Nonetheless, good public policy demands that we begin to tackle these issues, and that we concertedly apply our knowledge, skills and ingenuity to advance the state-of-the-art in that direction. E. S. Rubln F. C. McMichaei
Carnegie-Mellon University Pittsburgh, Pa. 15213 Volume 9, Number 6 , June 1975
497
