# US 10,501,345 B2 · Low risk chlorine dioxide onsite generation system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,501,345 B2 - Document ID: US10501345B2 - Status: Granted - Kind: B2 - Application number: 15/928,749 - Filed: 2018-03-22 - Published: 2019-02-21 - Granted: 2019-12-10 - Earliest claimed: 2017-08-17 - Assignees: Ecolab USA Inc. - Applicants: Ecolab USA, Inc. - Inventors: Kun Xiong; Emily Rader; James L. Jefferson; Felice DiMascio; Donald O'Brien; Nicholas Ryan Denny; Gary Tabor; David R. Papanek - Web page: https://patentgrep.com/patent/US10501345B2 ## CPC - C02F 1/50: by addition or application of a germicide or by oligodynamic treatment {(C02F1/4606, C02F1/467, C02F1/76 take precedence)} - B01J 19/0053: {Details of the reactor} - B01J 19/243: {spirally, concentrically or zigzag wound} - C01B 11/026: {from chlorate ions in the presence of a peroxidic compound, e.g. hydrogen peroxide, ozone, peroxysulfates} - C02F 1/686: {Devices for dosing liquid additives} - C02F 1/76: with halogens or compounds of halogens {(C02F1/4674 takes precedence)} - C02F 1/006: {Water distributors either inside a treatment tank or directing the water to several treatment tanks; Water treatment plants incorporating these distributors, with or without chemical or biological tanks (for settling tanks B01D21/24)} - C02F 2103/023: {Water in cooling circuits} - C02F 2209/005: Processes using a programmable logic controller [PLC] - C02F 2209/03: Pressure - C02F 2209/29: Chlorine compounds - C02F 2209/40: Liquid flow rate - C02F 2303/04: Disinfection - 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) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} ## Abstract The present disclosure generally relates to methods of treating process water using a reactor for generating chlorine dioxide onsite. The onsite generation system may include double ensured precursor feeding, effective reactor, automated control/alarm, and effective product delivery. The reactor may include a mixing device, a first feed line connected to the mixing device, and a second feed line connected to the mixing device. The reactor may include a proximal portion in fluid communication with the mixing device and a distal portion in fluid communication with a motive water line. The mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line may be positioned within the motive water line. ## Claims ### Claim 1 A method of treating process water, comprising: feeding a first solution comprising an acid through a first feed line into a mixing device; feeding a second solution comprising chlorate and hydrogen peroxide through a second feed line into the mixing device; mixing the first solution and the second solution in the mixing device to form a reaction mixture, wherein the mixing device is connected to a reactor; feeding the reaction mixture into the reactor; reacting the acid, the chlorate, and the hydrogen peroxide to produce chlorine dioxide in the reactor, wherein the reactor comprises a proximal portion connected to the mixing device and a distal portion in fluid communication with a motive water line, wherein the mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line are positioned within the motive water line, wherein the reactor comprises a coiled configuration having a coil plane angle of about 1 degrees to about 60 degrees; mixing the chlorine dioxide with motive water in the motive water line at the distal portion of the reactor; and injecting the chlorine dioxide and the motive water into the process water. ### Claim 2 (depends on 1) The method of claim 1, further comprising cooling the mixing device and the reactor with the motive water. ### Claim 3 (depends on 1) The method of claim 1, wherein the acid is sulfuric acid. ### Claim 4 (depends on 1) The method of claim 1, wherein the first feed line and the second feed line are opposite to and directed against each other. ### Claim 5 (depends on 1) The method of claim 1, wherein the motive water line comprises at least two longitudinal channels through which motive water may flow. ### Claim 6 (depends on 5) The method of claim 5, wherein the reaction mixture has a residence time in the reactor of at least about 0.1 minute, and a precursor velocity is at least about 25 cm/min, wherein the precursor velocity is a velocity of the first and second solutions. ### Claim 7 (depends on 6) The method of claim 6, wherein the reactor is operated at a pressure about equal to or greater than atmospheric pressure. ### Claim 8 (depends on 1) The method of claim 1, further comprising producing the chlorine dioxide at a rate ranging from about 0.001 lb/hour to about 20 lb/hour. ### Claim 9 (depends on 1) The method of claim 1, further comprising operating the reactor at a temperature ranging from about 2° C. to about 80° C. ### Claim 10 (depends on 1) The method of claim 1, further comprising determining a chlorine dioxide demand in the process water using measurements selected from a chlorine dioxide sensor, an oxidation and reduction potential, a flow meter, a microbiological measurement, and any combination thereof. ### Claim 11 (depends on 1) The method of claim 1, wherein a cooling tower comprises the process water. ### Claim 12 A method, comprising: feeding a first solution comprising an acid through a first feed line into a mixing device; feeding a second solution comprising chlorate and hydrogen peroxide through a second feed line into the mixing device; mixing the first solution and the second solution in the mixing device to form a reaction mixture, wherein the mixing device is connected to a reactor; feeding the reaction mixture into the reactor; reacting the acid, the chlorate, and the hydrogen peroxide to produce chlorine dioxide in the reactor, wherein the reactor comprises a proximal portion connected to the mixing device and a distal portion in fluid communication with a motive water line, wherein the mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line are positioned within the motive water line, wherein the reactor comprises a coiled configuration having a coil plane angle of about 1 degrees to about 60 degrees; mixing the chlorine dioxide with motive water in the motive water line at the distal portion of the reactor; and injecting the chlorine dioxide into an aqueous system. ### Claim 13 (depends on 12) The method of claim 12, wherein the reactor is in fluid communication with a product feed line. ### Claim 14 (depends on 12) The method of claim 12, further comprising determining a flow rate of the first solution in the first feed line. ### Claim 15 (depends on 12) The method of claim 12, further comprising determining a flow rate of the second solution in the second feed line. ### Claim 16 (depends on 12) The method of claim 12, further comprising determining a flow rate of a chlorine dioxide solution in a product feed line. ### Claim 17 (depends on 12) The method of claim 12, further comprising determining a flow rate of the motive water in the motive water line. ### Claim 18 (depends on 12) The method of claim 12, further comprising sensing a reactor pressure. ### Claim 19 A method of producing chlorine dioxide, comprising: feeding a first solution comprising an acid through a first feed line into a mixing device; feeding a second solution comprising chlorate and hydrogen peroxide through a second feed line into the mixing device; mixing the first solution and the second solution in the mixing device to form a reaction mixture, wherein the mixing device is in fluid communication with a reactor; feeding the reaction mixture into the reactor; reacting the acid, the chlorate, and the hydrogen peroxide in the reactor, wherein the reactor comprises a proximal portion in fluid communication with the mixing device and a distal portion in fluid communication with a motive water line, wherein the mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line are positioned within the motive water line, wherein the reactor comprises a coiled configuration having a coil plane angle of about 1 degree to about 60 degrees; and mixing chlorine dioxide with motive water in the motive water line at the distal portion of the reactor. ### Claim 20 (depends on 19) The method of claim 19, wherein the acid is sulfuric acid. ### Claim 21 (depends on 19) The method of claim 19, wherein the reactor is operated at a pressure about equal to or greater than atmospheric pressure. ### Claim 22 (depends on 19) The method of claim 19, further comprising producing the chlorine dioxide at a rate ranging from about 0.001 lb/hour to about 20 lb/hour. ### Claim 23 (depends on 19) The method of claim 19, further comprising operating the reactor at a temperature ranging from about 2° C. to about 80° C.