Process for promoting mercury retention in wet flue gas desulfurization systems
View Patent ↗A system and method is proposed for removing mercury from a process gas stream containing mercury. The proposed invention provides for contacting an aqueous desulphurization liquor with a flue gas stream to capture mercury that may be contained in the flue gas stream. A promoter is mixed with the liquor to prevent oxidized mercury in the liquor from reducing into elemental mercury.
1. A method of removing mercury from a flue gas stream, the method comprising the steps of:
contacting in a scrubbing tower an aqueous liquor with a flue gas stream containing mercury; and
mixing in a scrubbing tower the aqueous liquor with an oxidizer to prevent oxidized mercury contained in the aqueous liquor from being reduced to elemental mercury.
2. The method of claim 1 wherein the aqueous liquor comprises water and a reagent.
3. The method of claim 2 wherein the reagent comprises lime.
4. The method of claim 2 wherein the reagent comprises limestone.
5. The method of claim 1 wherein the oxidizer comprises a strong oxidizer.
6. The method of claim 5 wherein the strong oxidizer comprises hydrogen peroxide (H 2 O 2 ).
7. The method of claim 1 wherein the oxidizer comprises hydrogen peroxide (H 2 O 2 ).
8. A method of removing mercury from a flue gas stream, the method comprising the steps of:
contacting in a scrubbing tower an aqueous liquor with a flue gas stream containing mercury to remove mercury from the flue gas stream; and
mixing in a scrubbing tower the aqueous liquor with an oxidizer to prevent oxidized mercury contained in the aqueous liquor from being reduced to elemental mercury.
9. The method of claim 8 wherein the oxidizer comprises a strong oxidizer.
10. The method of claim 9 wherein the strong oxidizer comprises hydrogen peroxide (H 2 O 2 ).