# US 8,771,593 B2 · Method and device for preventing corrosion in hot water systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,771,593 B2 - Document ID: US8771593B2 - Status: Granted - Kind: B2 - Application number: 13/442,324 - Filed: 2012-04-09 - Published: 2012-09-20 - Granted: 2014-07-08 - Earliest claimed: 2007-07-24 - Assignees: Nalco Company - Applicants: Peter D. Hicks; David A. Grattan - Inventors: Peter D. Hicks; David A. Grattan - Web page: https://patentgrep.com/patent/US8771593B2 ## CPC - C02F 1/008: {Control or steering systems not provided for elsewhere in subclass C02F} - C02F 1/68: by addition of specified substances, e.g. trace elements, for ameliorating potable water (medicinal water A61K) - C02F 1/70: by reduction {(C02F1/4676 takes precedence)} - C02F 1/72: by oxidation {(C02F1/4672 takes precedence)} - C23F 11/08: in other liquids - C23F 15/00: Other methods of preventing corrosion or incrustation - F22B 37/025: {Devices and methods for diminishing corrosion, e.g. by preventing cooling beneath the dew point} - F22D 11/006: {Arrangements of feedwater cleaning with a boiler} - G05D 21/02: characterised by the use of electric means - C02F 2209/006: comprising a software program or a logic diagram - C02F 2209/04: Oxidation reduction potential [ORP] - C02F 2303/08: Corrosion inhibition - 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) - C23F: NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE (working metal by laser beams B23K26/00; desurfacing by applying flames B23K7/00; working of metal by electro-erosion B23H; producing decorative effects by removing surface material, e.g. by engraving, by etching, B44C1/22; electrolytic etching or polishing C25F); INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25 - F22B: METHODS OF STEAM GENERATION; STEAM BOILERS - F22D: PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES ## Abstract Disclosed is a method of controlling a real-time oxidation-reduction potential in a hot water system to inhibit corrosion in the hot water system. The method includes defining one or more operational protective zones in the hot water system. One or more of the operational protective zones includes an oxidation-reduction potential probe that is operable to measure a real-time oxidation-reduction potential in the hot water system at operating temperature and pressure. The probe transmits the measured real-time potential to the controller, which assesses and interprets the transmitted potential to determine whether it conforms to an oxidation-reduction potential setting. If the measured potential does not conform the oxidation-reduction potential setting, the controller is operable to feed or remove one or more active chemical species into or from the hot water system and further operable to change at least one system parameter. ## Claims ### Claim 1 A method of controlling a real-time oxidation-reduction potential (“ORP”) in a hot water system to reduce corrosion in the hot water system, the method comprising: (a) defining one or more operational protective zones (“zone” or “zones”) in the hot water system; (b) selecting at least two of the defined zones, wherein at least two of the selected zones includes at least one ORP probe operable to measure the real-time ORP and communicate with a controller; (c) either intermittently or continuously measuring the real-time ORP at one or more of the selected zones while the hot water system is at operating temperature and pressure; (d) transmitting the measured real-time ORP to the controller; (e) assessing whether the measured real-time ORP or a calculated ORP based upon the measured real-time ORP conforms to an ORP setting, wherein the ORP setting is either a same ORP setting for each of the selected zones or a different ORP setting for at least two of the selected zones; (f) performing at least one of the following actions if the measured real-time ORP or the calculated ORP does not conform to the ORP setting: (i) feeding an effective amount of one or more active chemical species into the hot water system, (ii) removing an effective amount of one or more active chemical species from the hot water system, and (iii) changing a system parameter; and (g) optionally ramping from one of the selected zones to another one of the selected zones after a triggering event. ### Claim 2 (depends on 1) The method of claim 1, wherein the ORP probe includes a temperature detector, a noble metal electrode, and a reference electrode. ### Claim 3 (depends on 1) The method of claim 1, wherein the triggering event is based upon a timetable. ### Claim 4 (depends on 1) The method of claim 1, wherein at least one of the selected zones is in a monitoring and/or alarm mode and at least one other selected zone is in a control mode. ### Claim 5 (depends on 4) The method of claim 4, wherein at least one of the selected zones is capable of switching either manually or automatically between the monitoring and/or alarm mode and the control mode. ### Claim 6 (depends on 1) The method of claim 1, wherein the ORP setting changes over time. ### Claim 7 (depends on 1) The method of claim 1, including determining a first ORP setting corresponding to a first selected zone, and optionally determining additional ORP settings corresponding to additional selected zones. ### Claim 8 (depends on 7) The method of claim 7, including independently determining the first ORP setting and/or independently determining each additional ORP setting corresponding to each additional selected zone. ### Claim 9 (depends on 1) The method of claim 1, including independently determining the ORP setting for each selected zone based upon operational limitations of the hot water system. ### Claim 10 (depends on 1) The method of claim 1, wherein the ORP setting is selected from the group consisting of: an ORP set point chosen from one or more single values and an ORP set range chosen from one or more ranges of values. ### Claim 11 (depends on 1) The method of claim 1, including measuring a first real-time ORP in a first selected zone and performing at least one of said actions to the first selected zone, if the first measured real-time ORP or a first calculated ORP based upon the first measured real-time ORP does not conform to the ORP setting for the first selected zone; and/or measuring the first real-time ORP and performing one of said actions at one or more other selected zones, if the first measured real-time ORP or the first calculated ORP does not conform to the ORP setting for the first selected zone; and/or measuring one or more real-time ORPs at one or more of the selected zones and calculating one or more other real-time ORPs for one or more other selected zones, based upon one or more of the measured real-time ORP(s). ### Claim 12 (depends on 1) The method of claim 1, wherein the measured real-time ORP or the calculated ORP indicates an amount of electrochemically active species in the respective selected zone or in another selected zone; and/or wherein the measured real-time ORP or the calculated ORP indicates an amount of a chemical that indirectly affects an amount of electrochemically active species in the respective selected zone or in another selected zone. ### Claim 13 (depends on 12) The method of claim 12, wherein the electrochemically active species directly influences the real-time ORP. ### Claim 14 (depends on 1) The method of claim 1, including automatically and/or manually performing at least one of said actions. ### Claim 15 (depends on 1) The method of claim 1, wherein the active chemical species is selected from the group consisting of: oxidants, reductants, corrosion-inhibitors, corrodants, and combinations thereof. ### Claim 16 (depends on 1) The method of claim 1, including operating the method over a network. ### Claim 17 (depends on 16) The method of claim 16, wherein the network is the Internet. ### Claim 18 (depends on 1) A digital storage medium having computer-executable instructions stored thereon, the instructions operable to execute the method of claim 1. ### Claim 19 (depends on 1) The method of claim 1, wherein the hot water system is selected from the group consisting of: fossil fuel fired water-tube or fire-tube boilers; hot water heaters; heat exchangers; steam generators; nuclear power electric systems including light water reactors, pressurized water reactors, and boiling water reactors; marine units; combustion engine and diesel coolant systems; evaporator systems; thermal desalination systems; evaporator systems; papermaking operations including pulping processes and bleaching processes; wafer polishing and planarization processes; combustion gas emissions; fermentation processes; geothermal processes; aqueous organic redox synthesis; polymerization processes; steam ejection equipment; processing operations; and ancillary devices attached thereto. ### Claim 20 (depends on 1) The method of claim 1, including removing an effective amount of oxygen from the hot water system. ### Claim 21 (depends on 20) The method of claim 20, further comprising using a gas permeable membrane to remove said oxygen. ### Claim 22 (depends on 20) The method of claim 20, further comprising using a deaerator to remove said oxygen. ### Claim 23 (depends on 1) The method of claim 1, wherein changing a system parameter comprises selecting at least one of the following actions: selecting a particular chemical feed pump design; selecting a particular condensate pump design; partitioning stream flow and quantity; blending system or process streams with different ORP properties in a controlled ratio; selecting materials of construction for operational protective zones based upon affinity for dissolved oxygen; impressing current to provide cathodic protection; introducing electromagnetic waves; adjusting physical properties; and combinations thereof. ### Claim 24 (depends on 1) A corrosion control device for a hot water system operable to implement the method of claim 1, the hot water system, having a plurality of operational protective zones (“zone” or “zones”), wherein at least two of the zones are selected zones, said device comprising: a receiver in communication with one or more oxidation-reduction potential (“ORP”) probes, a subset of the ORP probes being activated, each activated ORP probe operable to measure a real-time ORP at operating temperature and pressure, and at least two of the selected zones including at least one of the ORP probes; a processor operable to interpret the measured real-time ORP communicated to the receiver from each activated ORP probe, wherein the processor either interprets the measured real-time ORP directly or interprets a calculated ORP based upon the measured real-time ORP; and a transmitter in communication with a feeding device operable to manage introduction of one or more active chemical species into the hot water system to affect changes in the real-time ORP, wherein the processor is operable to send an output signal through the transmitter to the feeding device, if the interpreted real-time ORP does not conform to an ORP setting.