03948320 is referenced by 9 patents and cites 4 patents.

A method of liquefying a coal formation in situ wherein the coal formation has been preheated as by a coal gasification project, includes the steps of establishing injection and removal passages connecting the coal formation to the surface, injecting water having a temperature below the formation temperature into the formation to gradually lower the temperature of the formation while forming synthesis gas, injecting a solvent material, having the capability of dissolving the coal, into the formation after it has been reduced to the desired temperature, injecting synthesis gas into the formation to hydrogenate the coal, allowing the formation to subside as the coal is dissolved therein so that more surface area of coal is exposed to the solvent, and removing the admixture of coal and solvent material from the formation as a synthetic crude oil.

Title
Method of in situ gasification, cooling and liquefaction of a subsurface coal formation
Application Number
5/558423
Publication Number
3948320
Application Date
March 14, 1975
Publication Date
April 6, 1976
Inventor
Ruel C Terry
Denver
CO, US
Agent
Burton Crandell & Polumbus
Assignee
In Situ Technology
CO, US
IPC
E21B 43/24
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