Enhanced sorbent formulation for removal of mercury from flue gas

Patent metadata

Field	Value
Publication number	US-10967357-B2
Application number	US-201916250758-A
Country	US
Kind code	B2
Filing date	Jan 17, 2019
Priority date	Aug 11, 2015
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A mercury sorbent and method for enhancing mercury removal performance of activated carbon from flue gas by the addition of non-halogen ammonium-containing compounds are provided herein.

First claim

What is claimed is:

1. A mercury sorbent comprising:
a dry admixture comprising separate and distinct particles of
an adsorptive material comprising one or more of carbonaceous char, activated carbon, carbon black, reactivated carbon, zeolite, and alumina clay; and
a non-halogen ammonium-containing compound;

wherein the mercury sorbent has no halogen containing component.

2. The mercury sorbent of claim 1 , wherein the non-halogen ammonium-containing compound is selected from the group consisting of ammonium bicarbonate salts, ammonium phosphate salts, mixed salt ammonium phosphates, ammonium pyrophosphates, hydrogen ammonium phosphates, dihydrogen ammonium phosphates, urea-phosphate, urea, and combinations thereof.

3. The mercury sorbent of claim 1 , wherein the mercury sorbent comprises about 1 wt. % to about 20 wt. % non-halogen ammonium-containing compound based on the total weight of the mercury sorbent.

4. The mercury sorbent of claim 1 , further comprising an alkaline additive.

5. The mercury sorbent of claim 4 , wherein the alkaline additive is selected from the group consisting of calcium carbonate, calcium oxide, calcium hydroxide; magnesium carbonate, magnesium hydroxide, magnesium oxide, sodium carbonate, sodium bicarbonate, trisodium hydrogendicarbonate dihydrate, and combinations thereof.

6. The mercury sorbent of claim 1 , wherein the mercury sorbent has a mean particle diameter of about 1 μm to about 30 μm.

7. The mercury sorbent of claim 1 , wherein the adsorptive material is selected from the group consisting of carbonaceous char, activated carbon, carbon black, reactivated carbon, and combinations thereof.

8. The mercury sorbent of claim 1 , wherein the mercury sorbent has a surface area of at least 300 m 2 /g.

9. The mercury sorbent of claim 1 , wherein the dry admixture of mercury sorbent is formed by co-milling.

10. A method for removing mercury from flue gas comprising injecting a mercury sorbent comprising a dry admixture comprising separate and distinct particles of an adsorptive material comprising one or more of carbonaceous char, activated carbon, carbon black, reactivated carbon, zeolite, and alumina clay and a non-halogen ammonium-containing compound into the flue gas, wherein the mercury sorbent has no halogen containing component.

11. The method of claim 10 , wherein the non-halogen ammonium-containing compound is selected from the group consisting of ammonium bicarbonate salts, ammonium phosphate salts, mixed salt ammonium phosphates, ammonium pyrophosphates, hydrogen ammonium phosphates, dihydrogen ammonium phosphates, urea-phosphate, urea, and combinations thereof.

12. The method of claim 10 , wherein the mercury sorbent comprises about 1 wt. % to about 20 wt. % non-halogen ammonium-containing compound based on the total weight of the mercury sorbent.

13. The method of claim 10 , wherein the mercury adsorbent further comprises an alkaline additive.

14. The method of claim 13 , wherein the alkaline additive is selected from the group consisting of calcium carbonate, calcium oxide, calcium hydroxide; magnesium carbonate, magnesium hydroxide, magnesium oxide, sodium carbonate, sodium bicarbonate, trisodium hydrogendicarbonate dihydrate, and combinations thereof.

15. The method of claim 10 , wherein the mercury sorbent has a mean particle diameter of about 1 μm to about 30 μm.

16. The method of claim 10 , wherein the adsorptive material is selected from the group consisting of carbonaceous char, activated carbon, carbon black, reactivated carbon, and combinations thereof.

17. The method of claim 10 , wherein the adsorptive material and non-halogen ammonium-containing compound are injected simultaneously.

18. The method of claim 10 , wherein the adsorptive material is injected upstream of the air preheater.

19. The method of claim 10 , wherein the mercury sorbent has a surface area of at least 300 m 2 /g.

20. The method of claim 10 , wherein the dry admixture of mercury sorbent is formed by co-milling.

Assignees

• Calgon Carbon Corp

Inventors

• Mimna Richard A
• Tramposch Walter G

Classifications

• B01D2251/606

  Carbonates · CPC title

• B01D2253/106

  Silica or silicates · CPC title

• B01D2251/402

  of magnesium · CPC title

• B01D2251/61

  Phosphates · CPC title

• B01J20/02

  comprising inorganic material · CPC title