Calcium hypochlorite compositions comprising zinc salts and lime
View Patent ↗The present invention is directed to a water treatment composition, comprising: 35-95 wt % calcium hypochlorite; 1 to 50 wt % magnesium sulfate or a hydrate thereof; 0.1 to 10 wt % lime; and 0.1 to 55 wt % of a water soluble zinc salt or a hydrate thereof; wherein the weight percents are based on the total weight of the composition. The present invention is also directed to a water treatment tablet, comprising 35-95 wt % calcium hypochlorite; 1 to 50 wt % magnesium sulfate or a hydrate thereof; 0.1 to 10 wt % lime; and 0.1 to 10 wt % of a water soluble zinc salt or a hydrate thereof; wherein the weight percents are based on the total weight of the composition. Methods of treating recreational water using the compositions are also disclosed.
1. A method of treating recreational water, comprising the steps of:
(1) adding to said recreational water a granular water treatment composition comprising:
35 to about 90 wt% calcium hypochlorite;
10 to 50 wt% magnesium sulfate or a hydrate thereof;
0.5 to 5 wt% lime; and
1 to 37.5 wt% of a water soluble zinc salt or a hydrate thereof;
all weight percents based on the total weight of said composition; followed by
(2) adding to said recreational water one or more water treatment tablets comprising:
35 to about 85 wt% calcium hypochlorite;
15 to about 40 wt% magnesium sulfate or a hydrate thereof;
0.5 to 5.0 wt% lime; and
0.5 to 10 wt% of a water soluble zinc salt or a hydrate thereof;
all weight percents based on the total weight of said tablet.
2. The method of claim 1 , wherein said calcium hypochlorite in said granular water treatment composition comprises from about 40 to about 90 wt%, based on the total weight of said composition.
3. The method of claim 1 , wherein said calcium hypochlorite in said granular water treatment composition comprises from about 50 to about 70 wt%, based on the total weight of said composition.
4. The method of claim 1 , wherein said magnesium sulfate in said granular water treatment composition is magnesium sulfate heptahydrate.
5. The method of claim 4 , wherein said magnesium sulfate heptahydrate comprises from about 20 to about 40 wt%, based on the total weight of said composition.
6. The method of claim 4 , wherein said magnesium sulfate heptahydrate comprises from about 25 to about 35 wt%, based on the total weight of said composition.
7. The method of claim 1 , wherein said lime in said granular water treatment composition comprises from about 0.5 to 2.5 wt%, based on the total weight of said composition.
8. The method of claim 1 , wherein said lime in said granular water treatment composition comprises from about 1.0 to 2.0 wt%, based on the total weight of said composition.
9. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said granular water treatment composition is selected from the group consisting of zinc sulfate monohydrate, zinc sulfate heptahydrate, zinc carbonate, zinc carbonate hydroxide hydrate, zinc nitrate and hydrates thereof, zinc borate, zinc hydroxide, zinc phosphate and hydrates thereof, isomorphous zinc/magnesium salts, and combinations thereof.
10. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said granular water treatment composition comprises from about 5.0 to 37.5 wt%, based on the total weight of said composition.
11. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said granular water treatment composition comprises from about 10.0 to 13 wt%, based on the total weight of said composition.
12. The method of claim 1 , wherein said granular water treatment composition further comprises additional ingredients selected from the group consisting of scale inhibiting agents, residue dispersing agents, colorants, chelating agents, buffers, fragrances, algaecides, fungicides, flocculants, clarifiers, and combinations thereof, wherein said additional ingredients comprise from 0.01 to 20 wt%, based on the total weight of said granular water treatment composition.
13. The method of claim 12 , wherein said additional ingredients comprise from about 0.1 to about 20 wt% based on the total weight of said granular water treatment composition.
14. The method of claim 1 , wherein said granular water treatment composition further comprises at least about 17 wt% of water, based on the total weight of said granular water treatment composition.
15. The method of claim 14 , wherein said granular water treatment composition contains from about 18 to about 24 wt% water, based on the total weight of said composition.
16. The method of claim 1 , wherein said calcium hypochlorite in said water treatment tablet comprises from about 50 to about 85 wt%, based on the total weight of said tablet.
17. The method of claim 16 , wherein said calcium hypochlorite in said water treatment tablet comprises from about 60 to about 75 wt%, based on the total weight of said tablet.
18. The method of claim 1 , wherein said magnesium sulfate in said water treatment tablet is magnesium sulfate heptahydrate.
19. The method of claim 18 , wherein said magnesium sulfate heptahydrate in said water treatment tablet comprises from about 20 to about 30 wt%, based on the total weight of said tablet.
20. The method of claim 1 , wherein said lime in said water treatment tablet comprises from about 1.0 to 2.0 wt%, based on the total weight of said tablet.
21. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said water treatment tablet is selected from the group consisting of zinc sulfate monohydrate, zinc sulfate heptahydrate, zinc carbonate, zinc carbonate hydroxide hydrate, zinc nitrate and hydrates thereof, zinc borate, zinc hydroxide, zinc phosphate and hydrates thereof, isomorphous zinc/magnesium salts, and combinations thereof.
22. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said water treatment tablet comprises from about 0.5 to 5.0 wt%, based on the total weight of said tablet.
23. The method of claim 1 , wherein said water soluble zinc salt or a hydrate thereof in said water treatment tablet comprises from about 1.0 to 3.0 wt%, based on the total weight of said tablet.
24. The method of claim 1 , wherein said water treatment tablet further comprises additional ingredients selected from the group consisting of scale inhibiting agents, residue dispersing agents, colorants, chelating agents, buffers, fragrances, algaecides, fungicides, flocculants, clarifiers, and combinations thereof, wherein said additional ingredients comprise from 0.01 to wt%, based on the total weight of said tablet.
25. The method of claim 24 , wherein said additional ingredients comprise from about 0.1 to about 20 wt% based on the total weight of said tablet.
26. The method of claim 1 , wherein said water treatment tablet further comprises at least about 17 wt% of water, based on the total weight of said tablet.
27. The method of claim 26 , wherein said water treatment tablet contains from about 18 to about 24 wt% water, based on the total weight of said tablet.
28. The method of claim 1 , wherein the zinc concentration in said recreational water is maintained at about 0.5 - 5 ppm.
29. The method of claim 1 , wherein the free chlorine concentration in said recreational water is maintained at about 0.5 - 5 ppm.
30. A method of treating recreational water, comprising the steps of:
(1) adding to said recreation water a first application of a water treatment tablet, followed by
(2) adding to said recreational water a second application of said water treatment tablet; wherein said water treatment tablet comprises
35 to about 85 wt% calcium hypochlorite;
15 to about 40 wt% magnesium sulfate or a hydrate thereof;
0.5 to 5.0 wt% lime; and
0.5 to 10 wt% of a water soluble zinc salt or a hydrate thereof;
all weight percents based on the total weight of said tablet.
31. The method of claim 30 , wherein said calcium hypochlorite comprises from about 50 to about 85 wt%, based on the total weight of said tablet.
32. The method of claim 30 , wherein said calcium hypochlorite comprises from about 60 to about 75 wt%, based on the total weight of said tablet.
33. The method of claim 30 , wherein said magnesium sulfate is magnesium sulfate heptahydrate.
34. The method of claim 33 , wherein said magnesium sulfate heptahydrate comprises from about 15 to about 40 wt%, based on the total weight of said tablet.
35. The method of claim 33 , wherein said magnesium sulfate heptahydrate comprises from about 20 to about 30 wt%, based on the total weight of said tablet.
36. The method of claim 30 , wherein said lime comprises from about 0.5 to 5.0 wt%, based on the total weight of said tablet.
37. The method of claim 30 , wherein said lime comprises from about 1.0 to 2.0 wt%, based on the total weight of said tablet.
38. The method of claim 30 , wherein said water soluble zinc salt or a hydrate thereof is selected from the group consisting of zinc sulfate monohydrate, zinc sulfate heptahydrate, zinc carbonate, zinc carbonate hydroxide hydrate, zinc nitrate and hydrates thereof, zinc borate, zinc hydroxide, zinc phosphate and hydrates thereof, isomorphous zinc/magnesium 5 salts, and combinations thereof.
39. The method of claim 30 , wherein said water soluble zinc salt or a hydrate thereof comprises from about 0.5 to 5.0 wt%, based on the total weight of said tablet.
40. The method of claim 30 , wherein said water soluble zinc salt or a hydrate thereof comprises from about 1.0 to 3.0 wt%, based on the total weight of said tablet.
41. The method of claim 30 , wherein said tablet further comprises additional ingredients selected from the group consisting of scale inhibiting agents, residue dispersing agents, colorants, chelating agents, buffers, fragrances, algaecides, fungicides, flocculants, clarifiers, and combinations thereof, wherein said additional ingredients comprise from 0.01 to 20 wt%, based on the total weight of said tablet.
42. The method of claim 41 , wherein said additional ingredients comprise from about 0.1 to about 20 wt% based on the total weight of said tablet.
43. The method of claim 30 , wherein said tablet further comprises at least about 17 wt% of water, based on the total weight of said tablet.
44. The method of claim 43 , wherein said tablet comprises from about 18 to about 24 wt% water, based on the total weight of said tablet.
45. The method of claim 30 , wherein the zinc concentration in said recreational water is maintained at about 0.5 - 5 ppm.
46. The method of claim 30 , wherein the free chlorine concentration in said recreational water is maintained at about 0.5 - 5 ppm.