Synergistic methods for odor control
View Patent ↗An odor control composition may be dosed to a wastewater treatment system to control hydrogen sulfide levels. The composition may include a sulfide-reducing agent and an oxidizer. Synergy between the compounds of the odor control composition may facilitate efficient reduction of hydrogen sulfide levels. The sulfide-reducing agent and the oxidizer may be present in a single odor control composition or may be dosed to the system separately.
1. A method of controlling odor in a water treatment system, comprising:
introducing a process stream at an inlet of the water treatment system;
measuring a sulfide level at an outlet of the water treatment system;
selecting an odor control composition comprising a sulfide-reducing agent and an oxidizer, the oxidizer comprising about 0.1 to about 10 wt. % of the odor control composition; and
reducing the sulfide level measured at the outlet to below a threshold value by adding the selected odor control composition to the process stream at a dosage less than that which would be required if the sulfide-reducing agent and the oxidizer were acting alone.
2. The method of claim 1 , wherein the sulfide-reducing agent comprises a nitrate compound.
3. The method of claim 2 , wherein the sulfide-reducing agent comprises calcium nitrate.
4. The method of claim 2 , wherein the oxidizer comprises a chlorite compound.
5. The method of claim 4 , wherein the oxidizer comprises sodium chlorite.
6. The method of claim 1 , wherein the oxidizer comprises about 1 to about 2.5 wt. % of the odor control composition.
7. The method of claim 1 , wherein the odor control composition further comprises a pH elevating compound.
8. The method of claim 1 , wherein the sulfide-reducing agent and the oxidizer are added separately to the process stream.
9. The method of claim 8 , wherein the sulfide-reducing agent and the oxidizer are added to the process stream at different dosage points within the water treatment system.
10. The method of claim 1 , further comprising adjusting the amount of the odor control composition that is added to the process stream.
11. The method of claim 1 , wherein the threshold value is an atmospheric hydrogen sulfide level of less than about 50 ppm.