Composition for cleaning a heat transfer system having an aluminum component
View Patent ↗Disclosed herein is a cleaner concentrate comprising: greater than 10 weight percent of a freezing point depressant, 0.5 to 35 weight percent of oxalic acid, and an azole compound, wherein weight percent is based on the total weight of the cleaner concentrate.
1. A heat transfer system conditioner for use in a heat transfer system that has been pre-treated with a cleaning solution, the heat transfer system conditioner comprising:
a) water;
b) a water soluble alkaline metal phosphate;
c) one or more azole compounds; and
d) optionally, a corrosion inhibitor, scale inhibitor, acid neutralizer, colorant, surfactant, antifoam, stop-leak agent, or combinations thereof;
the cleaning solution comprising:
a) greater than 15 weight percent of a freezing point depressant based on total weight of the cleaning solution;
b) oxalic acid in an amount ranging from about 8 to about 35 weight percent or from about 5 to about 10 weight percent based on total weight of the cleaning solution; and
c) an azole compound;
wherein the cleaning solution is a uniform solution; and
wherein the solution is stable at about 10° F. to about 55° F.
2. The conditioner of claim 1 , wherein the water soluble alkaline metal phosphate is sodium phosphate or potassium phosphate.
3. The conditioner of claim 1 , wherein the water soluble alkaline metal phosphate is 0.2 to 15 wt % based on total weight of the conditioner.
4. The conditioner of claim 1 , wherein the one or more azole compounds are 0.05 to 5 wt % based on total weight of the conditioner.
5. The conditioner of claim 1 , wherein the stop-leak agent is attaclay or soybean meal.
6. The conditioner of claim 1 , wherein the pH is greater than or equal to 7.5 at 15° to 25° C.
7. The conditioner of claim 1 , wherein the pH is 8.5 to 11 at 15° to 25° C.
8. A heat transfer system conditioner for use in a heat transfer system that has been pre-treated with a cleaning solution, the heat transfer system conditioner comprising:
a) water;
b) one or more azole compounds;
c) an antifoam/surfactant;
d) a water soluble polymer; and
e) phosphoric acid; and
the cleaning solution comprising:
a) greater than 15 weight percent of a freezing point depressant based on total weight of the cleaning solution;
b) oxalic acid in an amount ranging from about 8 to about 35 weight percent or from about 5 to about 10 weight percent based on total weight of the cleaning solution;
c) an azole compound;
wherein the cleaning solution is a uniform solution; and
wherein the solution is stable at about 10° F. to about 55° F.
9. The conditioner of claim 8 further comprising sodium hydroxide.
10. The conditioner of claim 8 further comprising a corrosion inhibitor.
11. The conditioner of claim 10 , wherein the corrosion inhibitor is selected from the group consisting of an alkaline metal benzoate, alkaline metal molybdate, alkaline metal nitrite, and combinations thereof.
12. A heat transfer system conditioner for use in a heat transfer system that has been pre-treated with a cleaning solution, the heat transfer system conditioner comprising:
a) water;
b) one or more azole compounds;
c) an antifoam/surfactant;
d) a water soluble polymer;
e) phosphoric acid; and
f) a corrosion inhibitor selected from the group consisting of sodium benzoate, an alkaline metal molybdate, an alkaline metal nitrite, and combinations thereof; and the cleaning solution comprising greater than 15 weight percent of a freezing point depressant based on total weight of the cleaning solution.
13. The conditioner of claim 10 , wherein the corrosion inhibitor is magnesium nitrate.
14. The condition of claim 8 , wherein the one or more azole compounds is sodium tolytriazole.
15. The conditioner of claim 8 , wherein the antifoam/surfactant is nonionic.
16. The conditioner of claim 15 , wherein the nonionic antifoam/surfactant is a nonionic triblock copolymer.
17. The conditioner of claim 8 , wherein the water soluble polymer is a polyacrylate.
18. The conditioner of claim 17 , wherein the polyacrylate is sodium polyacrylate.
19. A heat transfer system conditioner for use in a heat transfer system that has been pre-treated with a cleaning solution, the heat transfer system conditioner comprising:
a) water;
b) one or more azole compounds;
c) an antifoam/surfactant;
d) a water soluble polymer;
e) phosphoric acid; and
f) dipotassium sebacate; and the cleaning solution comprising greater than 15 weight percent of a freezing point depressant based on total weight of the cleaning solution.
20. The conditioner of claim 8 , wherein the condition comprises:
a) 0.25 to 0.5 wt % of one or more azole compounds based on total weight of the conditioner;
b) 0.5 wt % of a nonionic triblock copolymer based on total weight of the conditioner;
c) 0.1 wt % of a polyacrylate based on total weight of the conditioner;
d) 0.75 to 5 wt % phosphoric acid based on total weight of the conditioner; and
e) 0.94 to 6.5 wt % sodium hydroxide based on total weight of the conditioner.
21. The conditioner of claim 20 further comprising 0.015 wt % magnesium nitrate based on total weight of the conditioner.
22. The conditioner of claim 20 further comprising 13 wt % sodium sebacate based on total weight of the conditioner.
23. A method of cleaning a heat transfer system comprising:
a) circulating a cleaning solution in the heat transfer system;
b) circulating the conditioner of claim 1 in the heat transfer system; and
c) flushing the heat transfer system.
24. The method of claim 23 , wherein the conditioner is circulated at a temperature less than the boiling temperature of the conditioner.
25. The method of claim 24 , wherein the temperature is between ambient and 80° C.
26. The method of claim 23 further comprising adding a heat transfer fluid after the conditioner is flushed from the heat transfer system.
27. The method of claim 23 , wherein the cleaning solution comprises about 8 to 35 wt % of oxalic acid.