# US 8,540,882 B2 · Process for enhanced total organic carbon removal while maintaining optimum membrane filter performance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,882 B2 - Document ID: US8540882B2 - Status: Granted - Kind: B2 - Application number: 12/843,631 - Filed: 2010-07-26 - Published: 2010-12-02 - Granted: 2013-09-24 - Earliest claimed: 2007-10-23 - Assignees: Siemens Industry, Inc. - Applicants: Gregg A. McLeod - Inventors: Gregg A. McLeod - Web page: https://patentgrep.com/patent/US8540882B2 ## CPC - C02F 1/444: {by ultrafiltration or microfiltration} - B01D 61/145: {Ultrafiltration} - B01D 61/147: {Microfiltration} - B01D 61/16: Feed pretreatment - B01D 61/22: Controlling or regulating - B01D 65/08: Prevention of membrane fouling or of concentration polarisation - B01D 2311/04: Specific process operations in the feed stream; Feed pretreatment - B01D 2321/162: Use of acids - B01D 2321/168: Use of other chemical agents - C02F 1/5236: {using inorganic agents} - C02F 1/66: by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) - C02F 2209/06: pH - C02F 2209/40: Liquid flow rate - C02F 2301/08: Multistage treatments, e.g. repetition of the same process step under different conditions - 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) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract One embodiment of a method to system for enhancing TOC removal while maintaining membrane filter performance is the implementation of a dual pH control system. This embodiment will enhance the ability to maximize TOC removal while maintaining optimum membrane filter performance. By adjusting pH, dosing a chemical coagulant and incorporating liquid-solids separation, a considerably higher degree of TOC removal is possible. By adjusting pH again after liquid-solids separation this embodiment can drastically increase the efficiency of the membrane microfiltration/ultrafiltration system. Thus pH control for soluble organic removal is critical. This pH level however may not be the ideal set point for minimizing membrane fouling which is the basis for this embodiment. An example: the pH set point for optimum soluble organic removal is designated to be 5.5. However, the optimum pH set point for optimum membrane performance is 7.0. This embodiment will show the reader that a two stage approach can accomplish the desired result. Stage 1 involves coagulant dosing, pH control, mixing and liquid-solids separation followed by Stage two which involves pH control, mixing and membrane filtration. ## Claims ### Claim 1 A process for optimizing the removal of total organic carbon (TOC) from water while enhancing the performance of a membrane filter in a filtration system, comprising: dispersing an effective amount of coagulant into a volume of water in a first tank; rapidly agitating said water in a first zone of said first tank, then agitating said water more slowly in a second zone of said first tank; adjusting a pH level of said water in said first tank to a first pH set point selected for optimum TOC removal; directing said water at said first pH set point through a liquid-solid separator device to remove chemically-precipitated particulates and into a second tank; rapidly agitating said water in a first zone of said second tank, then agitating said water more slowly in a second zone of said second tank; adjusting a pH level of said water in said second tank to a second pH set point selected for optimum performance of said membrane filter; and directing said water at said second pH set point through said membrane filter. ### Claim 2 (depends on 1) The process of claim 1, wherein said dispersing step includes metering said coagulant based upon a signal which corresponds to a flow rate of water into said first tank. ### Claim 3 (depends on 1) The process of claim 1, wherein said effective amount of coagulant is determined based upon the volume, TOC level and temperature of said water in said first tank. ### Claim 4 (depends on 1) The process of claim 1, further comprising suppressing the pH of said water prior to said coagulant dispersing step. ### Claim 5 (depends on 1) The process of claim 1, wherein said step for adjusting the pH level of water in said first tank includes dosing acid or base into said water. ### Claim 6 (depends on 5) The process of claim 5, wherein said adjusting step in said first tank includes activating a first metering pump in response to a signal from a first pH probe configured in said first tank. ### Claim 7 (depends on 1) The process of claim 1, wherein said step for adjusting the pH level of water in said second tank includes dosing acid or base into said water. ### Claim 8 (depends on 7) The process of claim 7, wherein said adjusting step in said second tank includes activating a second metering pump in response to a signal from a second pH probe configured in said second tank. ### Claim 9 (depends on 1) The process of claim 1, wherein said first pH set point ranges from 5.0 to 6.0 standard units and said second pH set point is at least 7.0 standard units. ### Claim 10 (depends on 1) The process of claim 1, wherein said coagulant comprises a metal based coagulant. ### Claim 11 (depends on 10) The process of claim 10, wherein said metal based coagulant is selected from the group consisting of aluminum sulfate, ferric chloride, ferric sulfate, poly aluminum chloride and aluminum chlorhydrate. ### Claim 12 (depends on 1) The process of claim 1, wherein said dispersing step includes injecting said coagulant into said water prior to flowing into said first tank. ### Claim 13 (depends on 1) The process of claim 1, wherein said dispersing step includes injecting said coagulant into said first tank. ### Claim 14 (depends on 1) The process of claim 1, wherein no coagulant is dispersed into water downstream of the liquid-solid separator device. ### Claim 15 (depends on 1) The process of claim 1, wherein the second pH set point is higher than the first pH set point. ### Claim 16 (depends on 1) The process of claim 1, further comprising performing an ion exchange operation upstream of said first tank. ### Claim 17 (depends on 1) The process of claim 1, further comprising performing a disinfection or a granular activated carbon adsorption operation downstream of said membrane filter.