Low Sulfur Coal Supplies for Environmental Purposes

2 Low Sulfur Coal Supplies for Environmental Purposes

Downloaded by RUTGERS UNIV on May 30, 2018 | https://pubs.acs.org Publication Date: August 1, 1974 | doi: 10.1021/ba-1973-0127.ch002

THOMAS W. HUNTER Division of Fossil Fuels, Bureau of Mines, U.S. Department of the Interior, Washington, D. C.

Because of limited domestic supplies of other basic energy sources, coal production must be expanded. Reserves of low sulfur coal are large, even in the East, but many problems restrict their availability. The major problem is inadequate productive capacity in the East. Except for metallurgical coals, Eastern production historically has been principally of higher sulfur coals which now are environmentally restricted. Strong incentives must be provided for large capital investments to increase Eastern coal productive capacity. The quickest solutions would be increased low sulfur coal production in the East, supplemented by shipments of Western coals into the Midwest; the relaxation of environmental restrictions, where feasible; and acceleration in the development of technologies to permit the use of higher sulfur coals.

Cince this volume emphasizes national concern with adequate supplies ^ of all forms of fuel consistent with environmental requirements, it is essential that coal be placed in perspective vis-a-vis other energy sources and the many problems associated with its availability both as a solid fuel and in converted form. If the nation's energy requirements are to be met and if a sound balance is to be achieved between indigenous and foreign sources of energy supply, the vital role that coal must play is underscored by the serious need for supplementary sources of natural gas, the decline in proved indigenous oil reserves, and the increased dependence on imported oil. Equally significant is that economic, technologic, and sociologie problems are delaying the availability of largescale nuclear power availabilities. 17 Jimeson and Spindt; Pollution Control and Energy Needs Advances in Chemistry; American Chemical Society: Washington, DC, 1974.

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Energy Needs Concern for supplies of low sulfur coals, and other coals which can meet environmental requirements through chemical processing and other technologies, is compounded by enormously increasing needs for energy fuels by electric utilities, the extent to which low sulfur coals are held and used for coke production for steelmaking (both at home and abroad), and the relative availabilities of the other energy sources. Electric power generation has become a basic must in our society, not only for our overall economic well-being but for such social goals as increased employment, better housing for an expanding population, and a better way of life for millions who do not yet enjoy our vaunted high standards of living. The demand for electricity approximately doubles every 10 years, so pending availabilities of nuclear power, the fossil fuels must expand their contribution to power generation. To the extent that domestic supplies of the other primary energy sources are limited, this means a much greater dependence on coal, either through increased availabilities of naturally low sulfur coal or through technological developments that will make coal environmentally acceptable. The major alternative for the short term is increased dependence on foreign sources of energy, with all the problems that this implies with respect to prices, reliabilities of supply, and changing international relationships. Although the percentage contribution of coal to electric power generation has declined, 1955 to 1970 tonnages consumed increased from 141 million to 320 million tons. Notwithstanding power generation from other sources, including nuclear power, it is estimated that utilities will need between 750 million and 1 billion tons of coal by the end of the century if the nation's total energy demand is to be satisfied. Will low sulfur coal in this magnitude, or its equivalent through process technology, be available for power generation alone by the year 2000, and what will the availabilities be in the near-term and intermediate periods? Coal Resources Our coal resources are large, even our reserves of low sulfur coals, when compared with the relatively limited resources of our other indigenous energy fuels. There are many problems involved in the availability of low sulfur coals, however, including their extent and location; strong deterrents to, or lack of incentives for increased production; their need in relation to other energy supplies, including imports; the development of technologies to condition higher sulfur coals to meet environmental standards; and increasingly severe sulfur limitations which correspondingly narrow even our low sulfur coal resource base.

Jimeson and Spindt; Pollution Control and Energy Needs Advances in Chemistry; American Chemical Society: Washington, DC, 1974.


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Low Sulfur Coal Supplies

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Among the major problems of low sulfur coal supply is the uneven distribution of reserves in relation to demand. Although major markets are in the East and Midwest, the largest reserves of low sulfur coals are in the West. Based on U.S. Geological Survey data, 57.5% of our identified coal resources (1024 billion tons) have a sulfur content of 1% or less, of which 928 billion tons are in the West and 95 billion tons in the East. In addition, however, there are approximately 141 billion tons of coal averaging between 1.1 and 2.0% sulfur content, of which 92 billion tons are in the East and 48 billion tons in the West. Preliminary studies by the Bureau of Mines estimate that there are 251 billion tons of low sulfur coal reserves (mineable coal) at less than 1000 ft in depth, of which an estimated 198 billion tons are in the West and 53 billion tons east of the Mississippi River. Of these totals, 30 billion tons are considered to be low sulfur strippable reserves in the West at less than 100 ft deep and 2 billion tons in the East. Preponderantly, however, low sulfur reserves are at depths which would require underground mining. Approximately 50% of these quantities is recoverable in mining. Supplemental surveys and analyses are being made by the Bureau of Mines of low sulfur coal reserves and production, separately for both the Appalachian region and the rest of the country. The low sulfur coals of the East are located primarily in the Southern Appalachian region (mostly in West Virginia, Virginia, and eastern Kentucky, with smaller amounts in Pennsylvania, Alabama, and Tennessee). There is very little low sulfur coal in the Midwest, which is a major area of electric power generation and other coal consumption. Even with washing, the high sulfur coals indigenous to the Midwest generally are above the sulfur limits of air pollution regulations in most states. Only the pyritic sulfur can be removed from the coal by conventional methods. Accordingly, to conform to regulations governing coal consumption, the huge markets of the Midwest will have to rely on the Southern Appalachian and Western areas for low sulfur coal supplies or on indigenous or other higher sulfur coals used with stack emission processes or other technological developments, including coal conversions to gaseous or liquid fuels. In the East, most of the low sulfur coals produced customarily have been used for the production of coke for steelmaking both at home and abroad rather than for power generation. Heretofore these high quality coals have been too costly for utility use. Much of the coal used for power generation has been low-cost strip-mined coal. According to the Federal Power Commission (FPC), in the third quarter of 1972 approximately 46% of low sulfur coal delivered to utilities in the East and 92% delivered to utilities in the West were from surface mines. Correspondingly, 54% of the low sulfur coals delivered in the East and only 8% delivered



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POLLUTION CONTROL AND ENERGY NEEDS

in the West were from underground mines. The F P C now is studying, on the basis of a new canvass of the utility industry, the delivery of coal for power generation by sulfur content by states. This information will serve as an excellent guide to the problem of low sulfur coal availabilities for power generation. Because of other quality characteristics, however, such as differences in ash fusion temperatures, some low sulfur coals are not usable in some present combustion facilities. The large low sulfur coal reserves of the West could become major suppliers to Midwestern markets as well as in their own areas. For example, using unit trains, Western coal now moves into Chicago and other Midwestern areas; these shipments were inconceivable only a few years ago. Although practically all Western coals shipped eastward are mined by low-cost stripping, deterrents to their immediate large-scale shipment to easterly markets are (1) their lower Btu content than Midwestern and Eastern coals because they are largely subbituminous and lignite coals; (2) their high transportation costs; and (3) some higher ash contents. In addition to unit trains there also are potentials for coal movements by pipeline and for the extra-high-voltage transmission of coal-produced energy. Coal slurry pipelines have proved their practicability. The best current example is the 175-mile line from the Black Mesa coalfield in Arizona to the Mohave Power Project in Nevada. Also there is the potential for the transmission of synthetic coal gas into markets far distant from coal and synthetic gas-producing areas. Although there are significant low sulfur coal resources in the East (95 billion tons of 1% and less sulfur content) where the major coal markets are located, productive facilities have not been developed commensurately (beyond the production of metallurgical coals and supplies for more or less indigenous areas). Instead, most of the large additional reserves of high grade, high sulfur but lower cost bituminous coals have been developed, historically because of their close proximity to the principal energy-consuming areas. As a result, environmental requirements, rules, and regulations are of very serious concern to coal producers and consumers alike, as well as to those who are concerned with environmental standards. The magnitude and complexities involved in environmental regulations are compounded by the manner in which they have been promulgated, including some progressively more severe limitations. Relatively little time has been allowed for the coal-producing and control equipment industries to adjust to these restrictions. As a result, we are realizing that the large reserves of our great energy resources no longer are abundantly usable. Because of evolving social concepts, our energy resource output is being sharply reduced. The regulations have added significantly to the problem of our national energy self-sufficiency and to the need for increasing reliance on foreign energy supplies. The


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Environmental Protection Agency (EPA) recently stated that about half of the new state standards limit the sulfur content of coal to less than 0.8%, even though it noted at the same time that not enough low sulfur coal supply is projected to meet these requirements. Accordingly, there will be limited supplies of low sulfur coal for power generation and other purposes unless it is determined that environmental standards need not be as stringent in some areas as initially considered.


Expectations Because of the tremendous influence air pollution regulations will have on the future, socially as well as economically, it is reasonable to expect that the standards should be reassessed from time to time on the basis of pertinent new facts, particularly medical and other technical considerations. If the standards in some areas are even only modestly higher than what are really needed, enormous unnecessary costs will accrue, cumulatively, to all Americans, including unnecessary limitations to energy supplies, higher consumer utility rates than might otherwise be necessary, and social programs that are related both directly and indirectly to energy costs and availabilities. If the 92 billion tons of low sulfur coal resources between 1.1 and 2.0% sulfur content in the East, or even an appreciable fraction of them, were permissible, the seriousness of our energy supply situation would be relieved considerably. Regulations should be as strong as is proved necessary by factual appraisal and reappraisal of all elements involved, but not more so. The overall objective is to preserve, even improve, the environment while at the same time to attain other social goals without severe disruption to essential economic processes. This requires both judgment in the determination and application of controls and continued progress in the development of additional low sulfur coal-producing capacities and of new technologies to bring about a more favorable balance between our environmental and energy objectives. It is essential that we have more detailed and accurate information on the extent, nature, and location of low sulfur coal reserves and some indications of their relative costs to consumers. Whatever the reserves, however, the availability of mining capacity will be the major factor in the availability of both low sulfur and other coals, including those needed for conversion into clean energy forms. In recent years practically all new deep-mine commercial capacity has been developed only under longterm contracts because large mines are developed for lengthy life spans. Contractual assurances of continuing markets and other strong incentives are necessary to encourage the large expenditures that will be required for the development of large-scale increases in capacity. Essentially this means long-term contracts with electric utilities.



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Another important factor in the availability of coal is an adequate supply of transportation facilities, particularly railroad hopper cars. There is little or no storage at the mines except for unit train shipments, so mines generally cannot operate without an adequate supply of coal cars, which determines the number of days of active mine operation. Because of the close affinity of coal'and rail transportation, the deterrents to expanded coal productive capacity also affect the development of new transportation facilities. Of considerable importance in the future will be an increase in the number of unit trains, which help to reduce transportation costs and the potentials for more coal slurry pipelines and for minemouth generating plants for the extra-high-voltage transmission of coalproduced electricity. While substantially increased low sulfur coal availabilities would be the quickest solution for immediate coal needs, the development of new technologies to make the burning of high sulfur coal environmentally acceptable, and the production of clean coal-energy through conversion in large volumes as soon as possible are tremendously important. Perhaps of first importance, because of their near-term implications, are commercially acceptable processes for the removal of pollutants from stack gases. These devices should be developed as quickly as possible. Other technologies that need more immediate attention because of the lead times essential to their development to economic viability are the gasification of coal (both for high Btu pipeline-quality gas and low Btu gas for industrial uses), liquefaction processes, and, very importantly, methods for the solvent refining of coal to produce clean coal-energy for use as either a liquid or a solid. Summary In summary, although we have large reserves of low sulfur coal nationwide, their location and markets are largely in contraposition. The preponderance of reserves is in the Wst, with lesser, but still significant reserves in Southern Appalachia. Major markets, however, are in the industrial East and Midwest, at greater distances than for coal previously used for power generation and other purposes. Principal concerns regarding low sulfur coal supplies are in the East, where the problem is not one of reserves but of inadequate productive capacity. Mining capacity in the East, except for metallurgical coal, historically has been developed for high sulfur coals relatively near the nation's principal energy-consuming areas. Uncertainties in energy supplies and trends, to which environmental restrictions have contributed significantly, have deterred the large capital investments necessary to increase substantially low sulfur coalproducing capacity. Strong incentives are vitally needed to overcome


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deterrents and to encourage these investments, however, particularly in consideration of the limitations to domestic supplies of other basic energy sources. The quickest solution would be substantial increases in low-sulfur coal production, for which more long-term contracts with utilities would serve as a major catalyst. Increased easterly shipments of Western coals also would help considerably, subject to the constraints of long-distance transportation costs and lower heat content. Equally important would be some relaxation of environmental restrictions wherever environmentally feasible and acceleration in the development of technologies to permit the use of our huge resources of high sulfur coals.


RECEIVED February 15, 1973.


Low Sulfur Coal Supplies for Environmental Purposes

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