Cleaning agent comprising a polyacrylate terpolymer for removal of fouling deposits from metal surfaces
A cleaning agent comprising a polyacrylate terpolymer and a maleic olefin compound may be added to an aqueous system having a metal surface, such as a metal surface of a heat exchanger, in a concentration sufficient to remove fouling deposits from the metal surface in neutral or alkaline conditions. The removal of fouling deposits with the application of the cleaning agent may occur while the system is shut down or in service.
1. A method of removing fouling deposits from a metal surface in an aqueous system comprising:
introducing a cleaning agent comprising a polyacrylate terpolymer and a maleic olefin compound to the aqueous system, wherein the maleic olefin compound is a water soluble maleic olefin polymer having a C 1 -C 30 group connected to the maleic olefin backbone through ester, amide, or imide functionalities, where the fouling deposits comprises iron scale, the method comprising the cleaning agent wetting the iron scale, and the amount of the cleaning agent being effective to remove fouling deposits from a metal surface located in the aqueous system; and
removing the fouling deposits.
2. The method of claim 1 , wherein the polyacrylate terpolymer is selected from the group consisting of alkyl functionalized poly(AA-AMPS), styrene sulfonate functionalized poly(AA-AMPS), and combinations thereof.
3. The method of claim 1 , wherein the effective amount of the cleaning agent ranges from about 0.1 ppm to about 10000 ppm based on a total amount of fluid in the aqueous system.
4. The method of claim 1 , wherein the metal surface is a metal surface of a heat exchanger.
5. The method of claim 1 , wherein the aqueous system is selected from the group consisting of a cooling tower, a cooling water system, an evaporation system, a boiler system, an air-conditioning system, a wastewater treatment system, a deionized water system, a gas or fluid scrubbing system, a gas or fluid absorption system, and combinations thereof.
6. The method of claim 1 , wherein the aqueous system further comprises at least one component selected from the group consisting of a biocide, a calcium component, a chlorine-containing component, a taggant, a phosphorous compound, and combinations thereof.
7. The method of claim 1 , wherein the removal of the fouling deposits from the metal surface comprises wetting the fouling deposits and suspending the fouling deposits in the aqueous system.
8. The method of claim 7 , further comprising the step of ejecting the fouling deposits out of the aqueous system through blowdown.
9. The method of claim 1 , wherein the metal surface is selected from the group consisting of an iron-containing surface, an aluminum-containing surface, a yellow metal surface, and combinations thereof.
10. The method of claim 1 , wherein the aqueous system has a pH from about 6.5 to about 7, where the wettability of the iron scale is improved as compared to a higher pH.
11. The method of claim 1 , wherein the cleaning agent is introduced when the aqueous system is shutdown or when the aqueous system is in operation.
12. The method of claim 1 , wherein the amount of the polyacrylate terpolymer in the cleaning agent ranges from about 0.0001 wt. % to about 1 wt. %, based on the total amount of cleaning agent.
13. The method of claim 1 , wherein the amount of maleic olefin compound in the cleaning agent ranges from 0.00001 wt. % to about 0.001 wt. %, based on the total amount of cleaning agent.
14. The method of claim 1 , wherein the fouling deposits are selected from a group consisting of phosphate scales, carbonate scales, sulfate scales, silica scales, and combinations thereof.
15. A treated aqueous system comprising:
an aqueous system having a metal surface having fouling deposits where the fouling deposits comprise iron scale; and
a cleaning agent comprising a polyacrylate terpolymer in an amount ranging from about 0.0001 wt. % to about 1 wt. % based on a total amount of cleaning agent and a maleic olefin compound in an amount ranging from 0.00001 wt. % to about 0.001 wt. % based on a total amount of the cleaning agent where the cleaning agent is present in an amount effective to remove the fouling deposits and where the cleaning agent wets the iron scale, wherein the maleic olefin compound is a water soluble maleic olefin polymer having a C 1 -C 30 group connected to the maleic olefin backbone through ester, amide, or imide functionalities.
16. The treated aqueous system of claim 15 , wherein the wherein the metal surface is a metal surface of a heat exchanger.
17. The treated aqueous system of claim 15 , wherein the aqueous system has a pH from about 6.5 to about 7, where the wettability of the iron scale is improved as compared to a higher pH.
18. The treated aqueous system of claim 15 , wherein the fouling deposits are selected from a group consisting of phosphate scales, carbonate scales, sulfate scales, silica scales, and combinations thereof.
19. The treated aqueous system of claim 15 , wherein cleaning agent is present in the aqueous system in an amount ranging from about 0.5 ppm to about 50 ppm based on a total amount of fluid in the aqueous system.