Patent ID: 8235117
Filing Date: 2012-08-07
Classification: E21B

Abstract:
1. A method of producing hydrocarbons in situ from a heavy-oil and tar sand fixed-bed, hydrocarbon deposit distributed within a porous formation, the porous formation disposed below a ground surface and including a high-permeability zone in the hydrocarbon deposit, the steps comprising: providing at least one injection well in the formation; providing at least one production well in the formation, a spacing between the injection well and the production well of at least 100 feet; first heating a thermal-energy carrier fluid in a range of 450 to 550 degrees F.; subsequently injecting the heated carrier fluid into the injection well; circulating the carrier fluid through the high-permeability zone in the hydrocarbon deposit and between the injection well and the production well so as to increase the transmissibility of at least a portion of the hydrocarbons in the formation; second heating the thermal-energy carrier fluid in a range of 1000 to 1400 degrees F.; subsequently injecting the heated carrier fluid into the injection well; circulating the carrier fluid through the high-permeability zone in the hydrocarbon deposit and between the injection well and the production well; mobilizing hydrocarbons in at least a portion of the hydrocarbon deposit in situ by heating at least a portion of the high-permeability zone and a portion of the surrounding hydrocarbon deposit to retorting temperatures; producing at least a portion of mobilized hydrocarbons by flowing the carrier fluid with the mobilized hydrocarbons through the production well to the ground surface; and subsequently on the ground surface fractionating the hydrocarbons in the carrier fluid and generating at least two fluid fractions having differing chemical compositions.