Coal liquefaction background

H. D. Schindler "Coal Liquefaction A Research Needs Assessment," Vol. 2, Technical Background, Final Report on DOE Contract Mo. DE-AC01-87ER30110, 1989. 

Background Indirect coal liquefaction differs fundamentally from direct coal hquefaction in that the coal is first converted to a synthesis gas (a mixture of H9 and CO) which is then converted over a catalyst to the final product. Figure 27-9 presents a simplified process flow diagram for a typical indirect coal hquefaction process. The synthesis gas is produced in a gasifier (see a description of coal gasifiers earlier in this section), where the coal is partially combusted at high temperature and moderate pressure with a mixture of oxygen and steam. In addition to H9 and CO, the raw synthesis gas contains other constituents (such as CO9, H9S, NH3, N9, and CHJ, as well as particulates. 

The purpose of the collection of papers in this volume is to review what can be said about the susceptibility to liquefaction of coals from different parts of the world. We and later authors will present data relative to coals of the areas with which we are familiar. However, with the Editor s approval, we are going to devote the first part of this paper to making some general remarks about coal geology and geochemistry, in the hope that this will provide a useful background to what comes later. 

---