# US 2008/0185145 A1 · Methods for extracting oil from tar sand > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185145 A1 - Document ID: US20080185145A1 - Status: Published application - Kind: A1 - Application number: 11/671,135 - Filed: 2007-02-05 - Published: 2008-08-07 - Earliest claimed: 2007-02-05 - Assignees: Superior Graphite Co. - Inventors: Peter R. Carney; Igor V. Barsukov; Frank Wawrzos; Jeff Radford - Web page: https://patentgrep.com/patent/US20080185145A1 ## CPC - E21B 43/2401: {by means of electricity} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract Hydrocarbon containing formations can be processed using an in-situ liquefaction technique. This new technique embodies systematic temperature elevation applied to subsurface formation allowing recoverable hydrocarbons to reach a Newtonian fluid viscosity suitable for extraction. ## Claims ### Claim 1 A method for heating a sub-surface tar sand formation comprising: making a plurality of boreholes into the tar sand formation, locating an electrical conductor in each borehole; conductively connecting the electrical conductors to a source of electrical current; and introducing electrical current to the conductors to resistively heat the tar sand formation. ### Claim 2 (depends on 1) The method of claim 1 wherein the electrical conductors are formed from a compacted bed of powdered or granular conductive material. ### Claim 3 (depends on 1) The method of claim 1 wherein the electrical conductors comprise electrodes. ### Claim 4 (depends on 2, 3) The method of claim 2 or 3 wherein the electrical conductors are formed from one or more carbonaceous material selected from the group consisting of graphitic, partially graphitized, and non-graphitic carbonaceous materials. ### Claim 5 (depends on 2, 3) The method of claim 2 or 3 wherein the electrical conductors are formed from one or more materials selected from the group consisting of natural crystalline flake graphite, partially graphitized cokes, calcined coke, green coke, coal, carbon black, synthetic graphite, vein graphite, amorphous graphite, synthetic graphite electrodes, coal tar, petroleum and mesophase pitch-based chemistries, and expanded graphite-based products. ### Claim 6 (depends on 2, 3) The method of claim 2 or 3 wherein the electrical conductors are formed from one or more non-carbonaceous conductive material selected from the group consisting of metals, metal-based alloys, composites, and blends and combinations thereof. ### Claim 7 (depends on 1) The method of claim 1 wherein the electrical conductors have a resistance of from 1×10−3 Ω·m meters to 1×10−8 Ω·m. ### Claim 8 (depends on 1) The method of claim 1 wherein the boreholes have a diameter of from approximately 3.8 cm to approximately 50.8 cm. ### Claim 9 (depends on 3) The method claim 3 wherein the electrodes comprise graphite electrodes having a diameter of from approximately 20.3 cm. to approximately 50.8 cm. ### Claim 10 (depends on 3) The method of claim 3 wherein the electrodes have a diameter smaller than the borehole and the electrodes, when located in their respective boreholes, are surrounded by a granular or powered conductive material. ### Claim 11 (depends on 5) The method of claim 5 wherein the conductive material has an angle of repose of from 30 degrees to 90 degrees. ### Claim 12 (depends on 2) The method of claim 2 wherein the conductors are formed inside the boreholes using a pile driver. ### Claim 13 (depends on 1) The method of claim 1 wherein the electric current is 3-phase AC. ### Claim 14 (depends on 1) The method of claim 1 wherein the electric current is DC. ### Claim 15 A system for heating a sub-surface tar sand formation comprising: a plurality of boreholes in the tar sand formation; an electrical conductor in each borehole; and a source of electrical current conductively connected to the conductors. ### Claim 16 (depends on 15) The system of claim 15 wherein the electrical conductors are formed from a compacted bed of powdered or granular conductive material. ### Claim 17 (depends on 15) The system of claim 15 wherein the electrical conductors comprise electrodes. ### Claim 18 (depends on 16, 17) The system of claim 16 or 17 wherein the electrical conductors are formed from one or more carbonaceous material selected from the group consisting of graphitic, partially graphitized, and non-graphitic carbonaceous materials. ### Claim 19 (depends on 16, 17) The system of claim 16 or 17 wherein the electrical conductors are formed from one or more materials selected from the group consisting of natural crystalline flake graphite, partially graphitized cokes, calcined coke, green coke, coal, carbon black, synthetic graphite, vein graphite, amorphous graphite, synthetic graphite electrodes, coal tar, petroleum and mesophase pitch-based chemistries, and expanded graphite-based products. ### Claim 20 (depends on 16, 17) The system of claim 16 or 17 wherein the electrical conductors are formed from one or more non-carbonaceous conductive material selected from the group consisting of metals, metal-based alloys, composites, and blends and combinations thereof. ### Claim 21 (depends on 15) The system of claim 15 wherein the electrical conductors have a resistance of from 1×10−3 Ω·m meters to 1×10−8 Ω·M. ### Claim 22 (depends on 15) The system of claim 15 wherein the boreholes have a diameter of from approximately 3.8 cm to approximately 50.8 cm. ### Claim 23 (depends on 17) The system claim 17 wherein the electrodes comprise graphite electrodes having a diameter of from approximately 20.3 cm. to approximately 50.8 cm. ### Claim 24 (depends on 17) The system of claim 17 wherein the electrodes have a diameter smaller than the borehole and the electrodes, when located in their respective boreholes, are surrounded by a granular or powered conductive material. ### Claim 25 (depends on 19) The system of claim 19 wherein the conductive material has an angle of repose of from 30 degrees to 90 degrees. ### Claim 26 (depends on 15) The system of claim 15 wherein the electric current is 3-phase AC. ### Claim 27 (depends on 15) The system of claim 15 wherein the electric current is DC.