Abstract

The Lawrence Livermore Laboratory (LLL) is currently involved in the study of in situ coal gasification for the Department of Energy. This is a high risk but potentially promising technology that may see commercial development by the late 1980’s. A principal coal source is the group of several thick, deeply buried western sub-bituminous coals of the Powder River Basin that currently cannot be mined economically. The gases produced by this process can be directly consumed in industrial boilers, upgraded to synthetic natural gas (SNG), or used as chemical feed stocks in lieu of petroleum.

In this paper, the concept of in situ coal gasification is briefly reviewed for those who may not be familiar with it. This is followed by a discussion of the Hoe Creek site geology and hydrology, and the results of Experiments I and II. Preparations are now underway for Experiment III which will be burned almost entirely with steam and oxygen, and should provide urgently needed data on process economics. Lastly, results from experiments designed to assess two major environmental concerns, cavity-induced subsidence and ground-water pollution, are presented.