Belgo-German experiment on underground gasification
The main objectives of the project were to prove, in a coal seam at 860 m depth, that it was possible to carry out an initial in-seam linkage between two vertical wells by reverse combustion, and to follow this operation with gasification by a mixture of air and steam. After many attempts to create a channel by reverse combustion, a new concept was demonstrated, based on the use of directional drilling techniques. After having carried out a controlled deviation with a small radius of curvature from one well, an in-seam horizontal drainhole was drilled and connected to the second well by sidetracking. The gasification stage proper took place between October 1986 and April 1987. The material balance for this period showed that 350 tonnes of coal had been affected of which 150 tonnes had been completely converted. This phase was characterised by the use of high pressures, by the use of a gasifying agent which included oxygen and foamy water as reactants, and by the production of a gas with a high methane content. The gas quality was excellent but the recovered flows were low. Overall, a new concept of gasification has been demonstrated in the Thulin in-situ trial in which the underground gasification of deep coal has been shown to be technically feasible.
Bibliographic Reference: EUR 12263 EN (1989) FS, 110 pp., ECU 10
ISBN: ISBN 92-825-9673-7;CD-NA-
Record Number: 198910988 / Last updated on: 1994-12-01
Original language: en
Available languages: en