Underground Coal Gasification from a Worldwide Point of View

Abstract

Underground coal gasification, UCG, has been applied on a large scale in the Soviet Union as alternative energy recovery technique since 1960s. A method suitable for US conditions, i.e., shallow depth and large seam thickness, was developed in 10 years and is both basically appropriate for large scale application and economically promising. The application of UCG at great depth is, however, considerably more difficult. Research and development projects on underground gasification at great depth have been carried out in Belgium, France, Great Britain, the Netherlands, and the F. R. Germany for about 10 years. Three field trials have been initiated in France and in Belgium by a joint Belgo-German field project. A number of technical uncertainties and problems resulted in the creation and maintenance of high permeability pathways in the seams and by corrosion of well equipment. Field trials were accompanied by research and development work in universities and other research institutes. Research works at the Technical University Aachen are discussed in this paper.