A Review of Underground Coal Gasification Research and Development in the United States
An intense and productive period of research and development on underground coal gasification (UCG) took place in the United States from the mid-1970’s through the late 1980’s. It began with the translation and review of Soviet literature and ended with the Rocky Mountain 1 field test. This demonstrated the feasibility of newly-developed technologies that form the basis of many UCG projects around the world today. This period began with little domestic understanding of UCG and ended with an accurate observation-based conceptual model and a corresponding predictive multi-physics mathematical model of the process. The many accomplishments of this period form the main content of this report. This report also covers recent U.S. activities and accomplishments during the period 2004-2015, and touches briefly on the Bureau of Mines efforts between 1948 and 1963. Most of the activities were funded by the United States Department of Energy and its predecessors. While private/commercially-funded activities are reviewed here, the emphasis is on government-funded work. It has a much greater extent of publicly available reports and papers, and they generally contain much greater technical detail. Field tests were the marquis activities around which an integrated multi-faceted program was built. These are described in detail in Section 4. Highlights from modeling efforts are briefly covered, as the program was integrated and well-rounded, with field results informing models and vice-versa. The primary goal of this report is to review what has been learned about UCG from the U.S. experience in aggregate. This includes observations, conclusions, lessons-learned, phenomena understood, and technology developed. The latter sections of this report review these things.