Environmental and Economic Aspects of Indirect Coal Liquefaction Processes: A Report Emphasizing the Relationship between Product Mix and Efficiency

摘要

This report covers environmental and economic aspects of three indirect liquefaction processes. Specifically, the following are addressed: U.S. coal resources; the Lurgi/Methanol, Lurgi/Methanol/Mobil M, and the Lurgi/Fischer-Tropsch indirect coal liquefaction processes; and environmental and economic aspects associated with the considered processes. Even though our coal resources are considered very large, the life expectancy of currently defined reserves would be quite limited if we were to derive an appreciable part of our fossil-fuel-derived energy from coal. The conservation of coal resources would be affected by conversion efficiencies, which vary with process and product mix. For the processes considered, for similar liquid-to-gas ratio values (product mix), the coal-to-methanol is the most efficient while the Fischer-Tropsch is the least efficient. For these processes, the cost per Btu of product at reasonable equivalent liquid/gas ratios is greatest for Fischer-Tropsch and the least for the coal-to-methanol process.