# US 11,897,794 B2 · Processes and systems for treating sour water > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,897,794 B2 - Document ID: US11897794B2 - Status: Granted - Kind: B2 - Application number: 18/061,147 - Filed: 2022-12-02 - Published: 2023-03-30 - Granted: 2024-02-13 - Earliest claimed: 2019-12-03 - Assignees: Saudi Arabian Oil Company - Applicants: Saudi Arabian Oil Company - Inventors: Guillaume Robert Jean-Francois Raynel - Web page: https://patentgrep.com/patent/US11897794B2 ## CPC - C02F 1/5236: {using inorganic agents} - C02F 9/00: Multistage treatment of water, waste water or sewage - C02F 1/46109: {Electrodes} - C02F 1/5281: {Installations for water purification using chemical agents} - C25B 1/26: Chlorine; Compounds thereof (by simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine C25B1/34) - C02F 1/463: by electrocoagulation - C02F 1/4674: {with halogen or compound of halogens, e.g. chlorine, bromine} - C02F 1/76: with halogens or compounds of halogens {(C02F1/4674 takes precedence)} - C02F 2001/5218: {Crystallization} - C02F 2101/101: {Sulfur compounds} - C02F 2101/18: Cyanides - C02F 2101/20: Heavy metals or heavy metal compounds - C02F 2101/345: {Phenols} - C02F 2103/365: {from petrochemical industry (e.g. refineries)} - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - C25B: ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR (anodic or cathodic protection C23F13/00; single-crystal growth C30B) ## Abstract Processes for producing olefins may include electrolyzing an aqueous solution comprising metal chloride, where electrolyzing the aqueous solution causes at least a portion of the metal chloride to undergo chemical reaction to produce a treatment composition comprising hypochlorite. The processes may further include contacting at least a portion of the treatment composition with the sour water at a pH from 8 to 12, where the sour water comprises sulfides and the contacting causes reaction of the sulfides in the sour water with the hypochlorite to produce a treated aqueous mixture comprising at least metal sulfates and metal chlorides, where the metal sulfates are present in the treated aqueous mixture as precipitated solids. The processes may further include separating the precipitated solids from the treated aqueous mixture to produce a treated effluent comprising at least the metal chloride. ## Claims ### Claim 1 A system for treating sour water, the system comprising: an aqueous solution preparation system comprising an aqueous solution comprising from 15 percent by weight (wt. %) to 30 wt. % of metal chloride and from 1 wt. % to 10 wt. % of metal hydroxide based on the total weight of the aqueous solution, where a metal of the metal chloride and a metal of the metal hydroxide comprise strontium, barium, or both; an electrolyzer disposed downstream from the aqueous solution preparation system, the electrolyzer comprising at least one anode, at least one cathode, and a power source electrically coupled to the at least one anode and the at least one cathode, the electrolyzer operable to pass an electric current through the aqueous solution to produce a treatment composition comprising hypochlorite; a reactor downstream from the electrolyzer, where the reactor has a sour water inlet operable to introduce the sour water to the reactor, and the reactor is operable to contact at least a portion of the treatment composition comprising the hypochlorite with the sour water at a pH from 8 to 12; and a separation device downstream from the reactor, where the separation device is operable to separate precipitated solids from a treated aqueous mixture to produce a solid product comprising metal sulfates and metal carbonates and a treated effluent comprising the metal chloride. ### Claim 2 (depends on 1) The system of claim 1, where the treated effluent further comprises the metal hydroxide. ### Claim 3 (depends on 2) The system of claim 2, further comprising a vacuum crystallization system downstream from the separation device, the vacuum crystallization system being operable to crystallin at least a portion of the metal chlorides and metal hydroxides in the treated effluent to form a crystallized product in the aqueous solution. ### Claim 4 (depends on 3) The system of claim 3, further comprising a second separation device downstream from the vacuum crystallization system, in which the second separation device is operable to separate the metal chloride and the metal hydroxide from the crystallization effluent to produce a crystallized solid and an ammonium chloride solution. ### Claim 5 (depends on 4) The system of claim 4, further comprising a recycle line fluidly coupled to the second separation device or the vacuum crystallization system and to the aqueous solution preparation system, the recycle line operable to recycle the crystallized solid back to the aqueous solution preparation system. ### Claim 6 (depends on 1) The system of claim 1, where: the sour water comprises sulfides and the contacting causes reaction of the sulfides in the sour water with the hypochlorite to produce the treated aqueous mixture comprising at least metal sulfates and metal chlorides, where the metal sulfates are present in the treated aqueous mixture as precipitated solids. ### Claim 7 (depends on 3) The system of claim 3, further comprising a condenser downstream of and fluidly coupled to the vacuum crystallization system, the condenser operable to condense water vapor from a water vapor outlet of the vacuum crystallization system to produce a purified water effluent. ### Claim 8 (depends on 7) The system of claim 7, where the condenser is fluidly coupled to the aqueous solution preparation system to pass the purified water from the condenser directly to the aqueous solution preparation system. ### Claim 9 (depends on 1) The system of claim 1, where the metal hydroxide is operable to maintain a pH in the electrolyzer in a range of from 8 to 12. ### Claim 10 (depends on 1) The system of claim 1, where the metal hydroxide is operable to maintain a pH in the reactor in a range of from 8 to 12. ### Claim 11 (depends on 1) The system of claim 1, where the treatment composition is passed from the electrolyzer to the reactor. ### Claim 12 (depends on 1) The system of claim 1, where the electrolyzer is fluidly coupled to the reactor. ### Claim 13 (depends on 1) The system of claim 1, wherein the electrolyzer comprises a vessel, a plurality of anodes, and a plurality of cathodes, where the plurality of anodes and the plurality of cathodes are distributed throughout the vessel.