Treating hard water using an acid salt-regenerated ion exchange resin

• US 9,556,043 B2
• Filed: 03/14/2013
• Issued: 01/31/2017
• Est. Priority Date: 12/13/2011
• Status: Active Grant

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Inventors: Everson, Terrence P., Wen, Li, Tan, Lylien, Voss, Peter, Toetschinger, Mark
• Primary Examiner(s): Barry, Chester
• Application Number:
  US13/802,870
• Publication Number:
  US 20130192637A1
• Time in Patent Office: 1,419 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: A47L 15/241 the dishes moving in a horizontal plane
• CPC Class Codes: A47L 15/4217 Fittings for water supply, e.g. valves or plumbing means to connect to cold or warm water lines, aquastops
• CPC Class Codes: A47L 15/4229 Water softening arrangements
• CPC Class Codes: B01J 39/05 in the strongly acidic form
• CPC Class Codes: B01J 39/07 in the weakly acidic form
• CPC Class Codes: B01J 39/08 Use of material as cation exchangers; Treatment of material for improving the cation exchange properties
• CPC Class Codes: B01J 39/19 obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds
• CPC Class Codes: B01J 39/20 obtained by reactions only involving unsaturated carbon-to-carbon bonds
• CPC Class Codes: B01J 47/15 for obtaining a solution having a fixed pH
• CPC Class Codes: B01J 49/06 containing cationic exchangers
• CPC Class Codes: B01J 49/53 for cationic exchangers
• CPC Class Codes: B01J 49/75 of water softeners
• CPC Class Codes: B08B 3/04 Cleaning involving contact with liquid
• CPC Class Codes: B08B 3/14 Removing waste, e.g. labels, from cleaning liquid; Regenerating cleaning liquidstreatment of water in general C02F
• CPC Class Codes: C02F 1/42 by ion-exchange ion-exchange in general B01J
• CPC Class Codes: C02F 2001/425 using cation exchangers
• CPC Class Codes: C02F 2209/00 Controlling or monitoring parameters in water treatment
• CPC Class Codes: C02F 2209/005 Processes using a programmable logic controller [PLC]
• CPC Class Codes: C02F 2209/06 pH
• CPC Class Codes: C02F 2303/16 Regeneration of sorbents, filters
• CPC Class Codes: D06F 39/007 : Arrangements of water softeners

Abstract

Methods and systems for acid regeneration of ion exchange resins are disclosed. Acid resins designed for use in a variety of cleaning application using a water source use a treated, softened, acidic water source according to the invention. Various methods of using the softened acidic water generated by acid regenerate-able ion exchange resins are disclosed to beneficially reduce spotting, filming and scale buildup on treated surfaces, reduce and/or eliminate the need for polymers, threshold reagents and/or rinse aids, and using protons generated in the acidic water effluent for triggering events useful in various cleaning applications.

Claims

1. A method for treating hard water using an acid salt regenerated ion exchange resin comprising:

contacting a hard water source with a water treatment composition in a service cycle,

wherein the water treatment composition comprises at least one ion exchange resin,

wherein the ion exchange resin generates a treated water source by exchanging protons on said resin for dissolved cations including water hardness ions and total dissolved solids in said hard water source, and wherein said ion exchange resin is regenerated using an acid salt regenerant;

generating the treated water source having a specific water specification, wherein the water specification is a hardness level of less than about 2 grains per gallon, a TDS less than about 300 ppm, and a pH less than about 6, wherein the treated water source is used for washing and/or rinsing in a variety of cleaning applications;

measuring pH and/or proton concentration and/or total dissolved solids within the water treatment composition, water source and/or treated water source, and

triggering an event as a result of the obtained measurement,

wherein the triggered event is selected from the group consisting of regenerating the resin of the water treatment component, varying a detergent or other chemistry addition to the treated water source and combinations thereof.

2. The method according to claim 1, wherein said ion exchange resin is a weak acid cation exchange resin selected from the group consisting of a cross-linked polyacrylic with carboxylic acid functional group, a cross-linked polymethacrylic with carboxylic acid functional group and mixtures of thereof, and/or a strong acid cation exchange resin selected from the group consisting of a polystyrene with sulfonic acid functional group, a polystyrene with sulfonic acid functional group and mixtures of thereof.

3. The method according to claim 2, wherein said ion exchange resin is a layered bed system employing at least two of said cation exchange resins.

4. The method according to claim 1, wherein a pH and/or proton concentration measurement is obtained from said treated water source.

5. The method according to claim 1, wherein a differential pH and/or proton concentration measurement is obtained from said water source and said treated water source.

6. The method according to claim 1, wherein the regeneration of the resin comprises providing said acid salt regenerant to the resin, displacing water hardness ions on the resin with protons from the acid regenerant, and generating a regeneration step effluent water.

7. The method of claim 1, wherein said regenerant is a combination of from about 10 wt-% to about 50 wt-% urea sulfate and from about 50 wt-% to about 90 wt-% alkali metal salt, or is a regenerant selected from the group consisting of sodium chloride, urea sulfate, urea, sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, citric acid, acetic acid, methane sulfonic acid and a combination thereof.