Composition and method for enhanced sanitation and oxidation of aqueous systems
This invention relates to a method for enhanced sanitation and oxidation of aqueous solutions at aquatic facilities. The method provides a means for the in-situ generation of chlorine dioxide from dilute solutions of chlorite anions at near neutral pH, and enhanced inactivation rates of microbiological organisms including cryptosporidium.
1. A method for enhanced inactivation of microbiological organisms including cryptosporidium in an aqueous solution of an aquatic facility, the method comprising:
sustaining a free bromine concentration of 1 ppm to 20 ppm as Br 2 ;
sustaining in said aqueous solution a chlorite anion concentration of no more than about 100 ppm to sustain a chlorine dioxide concentration from 20 ppb to 150 ppb as ClO 2 ;
sustaining a pH between 7.0 to 8.0;
adding a sulfate free radical precursor at an average daily rate of 1 ppb to 20 ppb per minute based on the volume of the said aqueous solution;
sustaining an effective amount of active catalyst that converts the sulfate free radical precursor to a sulfate free radical; and
wherein at least some portion of the chlorite anions and bromide anions resulting from the decomposition of chlorine dioxide and free bromine are regenerated in-situ to form chlorine dioxide and free bromine.
2. The method of claim 1 , further comprising a chelant.
3. The method of claim 1 , further comprising a dispersant.
4. The method of claim 1 , further comprising from 10 to 100 ppm of cyanuric acid.
5. The method of claim 1 , wherein the catalyst comprises at least one of cobalt and ruthenium.
6. The method of claim 1 , wherein the catalyst comprises at least one of: cobalt, ruthenium, cerium, vanadium, iron, manganese, and nickel.
7. The method of claim 1 , wherein the sulfate free radical precursor comprises peroxymonosulfate.
8. The method of claim 1 , wherein the sulfate free radical precursor comprises at least one of sodium persulfate and potassium persulfate.
9. The method of claim 1 , wherein the catalyst comprises at least one of: copper, silver, iron, and manganese.
10. A method for enhanced inactivation of microbiological organisms including cryptosporidium in an aqueous solution of an aquatic facility, the method comprising:
sustaining a sustaining a free bromine concentration of 1 ppm to 20 ppm as Br 2 ;
sustaining in said aqueous system a chlorite anion concentration of no more than about 100 ppm to sustain a chlorine dioxide concentration from 20 ppb to 150 ppb as ClO 2 ;
sustaining a pH between 7.0 to 8.0;
adding peroxymonosulfate at an average daily rate of 1 ppb to 20 ppb per minute based on the volume of the aqueous solution; and
wherein at least some portion of the chlorite anions and bromide anions resulting from the decomposition of chlorine dioxide and free bromine are regenerated in-situ to form chlorine dioxide and free bromine.
11. The method of claim 10 , further comprising an effective amount of active catalyst.
12. The method of claim 11 , wherein the catalyst is selected from at least one of cobalt and ruthenium.