| abstract |
An improved process for recovering shale oil from in-situ shale comprising the steps of: (1) mining a first portion of said shale; (2) fragmenting a second portion of said shale; (3) introducing into said second portion a mixture of gases comprising a molecular oxygen supplying gas, carbon dioxide and hydrogen sulfide while maintaining a temperature sufficient to convert kerogen in said second portion to shale oil and to produce carbon dioxide, hydrogen sulfide, gaseous hydrocarbons and other combustion and inert gases; (4) separating said shale oil from an offgas containing said carbon dioxide, hydrogen sulfide, gaseous hydrocarbons and other combustion and inert gases; (5) separating hydrogen sulfide and a first portion of carbon dioxide from a gas of low sulfur content and increased heating value comprising said gaseous hydrocarbons and other combustion and inert gases and a second portion of said carbon dioxide; and (6) recycling said hydrogen sulfide and said first portion of said carbon dioxide to step (3). |