Low-rank-coal study national needs for resource development. Volume 1. Executive summary

Abstract

Low-rank coals - lignite and subbituminous - are those which have been subjected to the least amount of metamorphic change during the coal-forming process. As such, they retain greater fractions of moisture and volatile matter from the original peat material, and contain less fixed carbon, than the high-rank coals - bituminous and anthracite. The primary measure used to classify the lower ranks of coal is heating value. Other important characteristics which distinguish the low-rank coals from high-rank coals are discussed in this report. Low-rank coals represent a major, and largely untapped, energy resource for this country. Very extensive deposits of lignite and subbituminous coal exist in the western states, the Gulf coast, and Alaska. Major deposits of low-rank coal are also found in many other countries, most notably the USSR, Australia, Canada, and the central and eastern European nations. Worldwide coal statistics indicate that low-rank coals account for roughly one-third of the total resource and current production tonnages. This report recommends a comprehensive national research, development, and demonstration (RD and D) program to enhance the development of low-rank coals. The major conclusion of this study is that the unique properties of these coals affect the technologies for their extraction, preparation,more » direct use, and conversion and justify a separate focus on low-rank coals in the national RD and D efforts.« less