GB660161A - Generation of synthesis gas by subterranean gasification - Google Patents

Abstract

660,161. Underground gasification. DERN, S. G. (In Situ Gases, Inc.). March 16, 1949, No. 7203/49. Class 55 (ii). In an underground gasification process for the production of synthesis gas, two air inlet ducts are driven horizontally into the carbonaceous deposit, e.g. coal or oil sand, to meet in a V and a gas outlet duct is driven mid-way between them so as to terminate at the apex of the V, the ducts lying in one horizontal plane, and sharp capes being formed where they meet. The carbonaceous material exposed in the inlet ducts is ignited and oxygen enriched air blown in to maintain the combustion which, as it advances, causes the capes to spall away, the debris blocking the end of the outlet duct with burning embers through which the generated gases must pass to reach the outlet duct. Double inlet ducts 1. and 3 and a double outlet duct 4 are first driven parallel to each other into the deposit, lateral tunnels 5, 6, 7 and 8 then being bored from the ducts 1 and 3 to meet the ducts 4 at a point 11. Fires are started in tunnels 5 and 8 and air charged with oxygen and steam blown into tunnels 1 and 3 by blowers 14 and 15, generatedgas being withdrawn through ducts 4 by an exhauster 20. As combustion proceeds, the sharp capes at the meeting point 11 of the tunnels fall away, a pile of loose burning embers forming at the inner end of tunnel 4. Combustion products are withdrawn through the embers which constitute a reduction zone. The composition of the outlet gas is controlled by adjustment of the amount of oxygen and steam used and, to assist the conversion, powdered or gaseous catalysts may be introduced in the air blast. Alternatively, the gas may be reformed catalytically after leaving the outlet duct 4.