Systems and methods of reducing selenium contamination in waste water
AssigneeGeneral Electric Company
InventorRaymond Raulfs Gansley
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Abstract
A method of reducing selenium contamination in a waste water stream is described herein. The method includes channeling a flue gas stream through an absorber, contacting the flue gas stream with an aqueous alkaline-based slurry, such that any selenium byproduct in the flue gas stream forms a selenium compound within the aqueous alkaline-based slurry, controlling oxidation of the selenium compound in the aqueous alkaline-based slurry, and adding a precipitation agent to the aqueous alkaline-based slurry to cause the selenium compound within the aqueous alkaline-based slurry to precipitate.
Claims20
A method of reducing contamination in a waste water stream, the method comprising:
- channeling a flue gas stream through an absorber;
- contacting the flue gas stream with an aqueous alkaline-based slurry, such that any selenium byproduct in the flue gas stream forms into selenite, in an aqueous phase, within the aqueous alkaline-based slurry;
- controlling oxidation of the selenite in the aqueous alkaline-based slurry;
- and
- adding a precipitation agent to the aqueous alkaline-based slurry, wherein the precipitation agent is configured to react with and cause the selenite to precipitate from the aqueous phase to solidify into at least one of selenium sulfide, elemental selenium, or other solid selenium compounds.
A flue gas desulfurization system comprising:
- an absorber comprising a reservoir configured to collect an aqueous alkaline-based slurry following contact with a flue gas stream, wherein the aqueous alkaline-based slurry includes selenite dissolved therein in an aqueous phase, the selenite derived from a selenium byproduct included within the flue gas stream;
- a sulfite sensor configured to monitor a sulfite concentration of the aqueous alkaline-based slurry in the reservoir;
- an air injection system operatively coupled with the sulfite sensor, wherein the air injection system is configured to inject a stream of air into the reservoir at a flow rate determined as a function of the sulfite concentration;
- and
- an additive injection system coupled in flow communication with the reservoir, wherein the additive injection system is configured to supply a precipitation agent to the aqueous alkaline-based slurry, wherein the precipitation agent is configured to react with and cause the selenite to precipitate from the aqueous phase to solidify into at least one of selenium sulfide, elemental selenium, or other solid selenium compounds.
A power plant comprising:
- a boiler configured to generate a flue gas stream, wherein the flue gas stream includes a selenium byproduct;
- and
- a flue gas desulfurization system comprising:
- an absorber comprising a reservoir configured to collect an aqueous alkaline-based slurry following contact with the flue gas stream, wherein the aqueous alkaline-based slurry includes selenite dissolved therein in an aqueous phase, the selenite derived from the selenium byproduct;
- a sulfite sensor configured to monitor a sulfite concentration of the aqueous alkaline-based slurry in the reservoir;
- an air injection system communicatively coupled with the sulfite sensor, wherein the air injection system is configured to inject a stream of air into the reservoir at a flow rate determined as a function of the sulfite concentration;
- and
- an additive injection system coupled in flow communication with the reservoir, wherein the additive injection system is configured to supply a precipitation agent to the aqueous alkaline-based slurry, wherein the precipitation agent is configured to react with and cause the selenite to precipitate from the aqueous phase to solidify into at least one of selenium sulfide, elemental selenium, or other solid selenium compounds.
Dependencies are inferred from the claim text.