# US 9,752,422 B2 · Direct electrical steam generation for downhole heavy oil stimulation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,752,422 B2 - Document ID: US9752422B2 - Status: Granted - Kind: B2 - Application number: 14/532,778 - Filed: 2014-11-04 - Published: 2015-05-07 - Granted: 2017-09-05 - Earliest claimed: 2013-11-04 - Assignees: Donaldson Engineering, Inc. - Applicants: A. Burl Donaldson - Inventors: A. Burl Donaldson - Web page: https://patentgrep.com/patent/US9752422B2 ## CPC - E21B 43/2401: {by means of electricity} - E21B 36/006: {Combined heating and pumping means} - E21B 43/24: using heat, e.g. steam injection - Y02E 60/32: Hydrogen storage - Y02E 60/36: Hydrogen production from non-carbon containing sources, e.g. by water electrolysis - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A method of downhole steam generation comprising determining a desired level of electrical conductivity for water to be converted to steam in a downhole location, acquiring a main feedwater supply, wherein water of the main feedwater supply has an electrical conductivity lower or higher than the desired level, mixing water of the main feedwater supply with water from one or more sidestreams to generate a resultant stream with an electrical conductivity of about the desired level, pumping the resultant stream to the downhole location, and passing an electrical current through the resultant stream in the downhole location to generate steam. ## Claims ### Claim 1 A method of downhole steam generation, the method comprising the steps of: determining a desired level of electrical conductivity for water to be converted to steam in a downhole location; acquiring a main feedwater supply, wherein water of the main feedwater supply has an electrical conductivity lower than the desired level; mixing water of the main feedwater supply with water from one or more sidestreams having an electrical conductivity higher than the desired level to generate a resultant stream with an electrical conductivity of about the desired level; pumping the resultant stream to the downhole location; and passing an electrical current through the resultant stream in the downhole location to generate steam. ### Claim 2 (depends on 1) The method of claim 1 wherein one or more of the sidestreams comprises one or more of the group consisting of carbonic acid and sodium bi-sulfite. ### Claim 3 (depends on 1) The method of claim 1 wherein one or more of the sidestreams comprises produced water. ### Claim 4 (depends on 3) The method of claim 3 wherein the produced water is first passed through a water softener. ### Claim 5 (depends on 1) The method of claim 1 wherein the acquiring step comprises varying a flow rate based on energy input to the resultant stream. ### Claim 6 (depends on 1) The method of claim 1 wherein the steam generated has a mass fraction of vapor to total water of 40% to 80%. ### Claim 7 (depends on 1) The method of claim 1 wherein the passing step comprises employing one or more electrodes with outlets of the resultant stream spaced therebetween. ### Claim 8 A method of downhole steam generation, the method comprising the steps of: determining a desired level of electrical conductivity for water to be converted to steam in a downhole location, the desired level comprising a conductivity that results in a target power level being maintained in the downhole location; acquiring a main feedwater supply, wherein water of the main feedwater supply has an electrical conductivity higher than the desired level; mixing water of the main feedwater supply with water from one or more sidestreams having an electrical conductivity lower than the desired level and adjusting a flow of the one or more sidestreams based on conductivity of a flow of feedwater to generate a resultant stream with an electrical conductivity of about the desired level; pumping the resultant stream to the downhole location; and passing an electrical current through the resultant stream in the downhole location to generate steam. ### Claim 9 (depends on 8) The method of claim 8 wherein one or more of the sidestreams is first passed through a reverse osmosis membrane. ### Claim 10 (depends on 8) The method of claim 8 wherein the acquiring step comprises varying a flow rate based on energy input to the resultant stream. ### Claim 11 (depends on 8) The method of claim 8 wherein the steam generated has a mass fraction of vapor to total water of 40% to 80%. ### Claim 12 (depends on 8) The method of claim 8 wherein the passing step comprises employing one or more electrodes with outlets of the resultant stream spaced therebetween. ### Claim 13 (depends on 8) The method of claim 8 wherein the target power level is determined based on electrical supply capability of equipment. ### Claim 14 A method of downhole steam generation, the method comprising the steps of: determining a desired level of electrical conductivity for water to be converted to steam in a downhole location, the desired level comprising a conductivity that results in a target power level being maintained in the downhole location; acquiring a main feedwater supply, wherein water of the main feedwater supply has an electrical conductivity lower or higher than the desired level; adjusting a flow of one or more sidestreams based on conductivity of a flow of feedwater; mixing water of the main feedwater supply with water from the one or more sidestreams to generate a resultant stream with an electrical conductivity of about the desired level; pumping the resultant stream to the downhole location; and passing an electrical current through the resultant stream in the downhole location to generate steam. ### Claim 15 (depends on 14) The method of claim 14 wherein one or more of the sidestreams comprises one or more of the group consisting of carbonic acid and sodium bi-sulfite. ### Claim 16 (depends on 14) The method of claim 14 wherein one or more of the sidestreams comprises produced water. ### Claim 17 (depends on 16) The method of claim 16 wherein the produced water is first passed through a water softener. ### Claim 18 (depends on 14) The method of claim 14 wherein one or more of the sidestreams is first passed through a reverse osmosis membrane. ### Claim 19 (depends on 14) The method of claim 14 wherein sidestreams are chosen based on whether water of the main feedwater supply has an electrical conductivity higher or lower than the desired level. ### Claim 20 (depends on 14) The method of claim 14 wherein the acquiring step comprises varying a flow rate based on energy input to the resultant stream. ### Claim 21 (depends on 14) The method of claim 14 wherein the steam generated has a mass fraction of vapor to total water of 40% to 80%. ### Claim 22 (depends on 14) The method of claim 14 wherein the passing step comprises employing one or more electrodes with outlets of the resultant stream spaced therebetween. ### Claim 23 (depends on 14) The method of claim 14 wherein the target power level is determined based on electrical supply capability of equipment.