Brief History of UCG
(Prior to 1990)
The in-seam gasification of coal has
been an objective of coal research since the early UK experiments
in Durham in the early 1920's. Trials were started in earnest in
the former Soviet Union in the 1930's and continued at a high level
of activity after the second world war both there and in Europe
(e.g. Newman Spinney in the UK). These trials established the basic
technology of UCG, and a number of commerical sized schemes were
initiated in the Soviet Republics, most notably in Russia and Uzbekistan.
American trials in the 1970's and 1980's advanced the technology of control (through the use of the continuous retractable injection point, or CRIP technique), and oxygen injection, and by the end of the 1980's, UCG was considered in the United States to be a technology, ready for commercialisation. Although commercial projects were evaluated, most notably the proposed SNG plant at Rawlins, Wyoming, the low cost of natural gas in the early 1990's prevented these projects from being realised.
The objective of the European trial was to test the use of directional in-seam drilling to construct the well configuration and to evaluate the feasibility of gasification at depths greater than 500m.
The Spanish trial was completed successfully and a feasibility study has now been initiated by the UK (1999-2003) into whether UCG can enhance the value of the country's extensive coal reserves both on and offshore.
Meanwhile, in the 1980's the European Commision was encouraging Member States to re-examine UCG as an alternative to conventional mining in the thinner, deeper and more disturbed coal seams of Europe. This led to the Thulin trial in Belgium (1982-1987), the European Working Group on UCG (published in 1989) and the European trial of UCG in Spain (1992-1999).
UCG Trials as function of coal seam depth
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