Sorbents for coal combustion

• US 8,114,368 B2
• Filed: 06/27/2011
• Issued: 02/14/2012
• Est. Priority Date: 03/17/2005
• Status: Active Grant

• Current Assignee: Nox Ii Ltd. (Arthur J Gallagher & Company)
• Original Assignee: Nox Ii Ltd. (Arthur J Gallagher & Company)
• Inventors: Comrie, Douglas C.
• Primary Examiner(s): VANOY, TIMOTHY C
• Application Number:
  US13/169,187
• Publication Number:
  US 20110281222A1
• Time in Patent Office: 232 Days
• Field of Search: 431/2, 423/210, 423/242.1, 423/244.01, 423/244.07, 423/DIG.5, 445/05, 446/03, 446/04, 446/20, 446/21, 446/22, 446/24, 422/105, 422/108, 422/111
• US Class Current: 423/210
• CPC Class Codes: B01D 2253/104 Alumina
• CPC Class Codes: B01D 2253/11 Clays
• CPC Class Codes: B01D 2257/30 Sulfur compounds
• CPC Class Codes: B01D 2257/602 Mercury or mercury compounds
• CPC Class Codes: B01D 53/04 with stationary adsorbents B01D53/025 takes precedence
• CPC Class Codes: B01D 53/30 Controlling by gas-analysis apparatus regulating non electrical variables in general G05D
• CPC Class Codes: B01D 53/485 containing only one sulfur compound other than sulfur oxides or hydrogen sulfide
• CPC Class Codes: B01D 53/64 Heavy metals or compounds thereof, e.g. mercury
• CPC Class Codes: B01D 53/78 with gas-liquid contact
• CPC Class Codes: B01J 20/041 Oxides or hydroxides
• CPC Class Codes: B01J 20/043 Carbonates or bicarbonates, e.g. limestone, dolomite, aragonite
• CPC Class Codes: B01J 20/046 containing halogens, e.g. halides
• CPC Class Codes: B01J 20/06 comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/12 Naturally occurring clays or bleaching earth
• CPC Class Codes: B01J 20/16 Alumino-silicates B01J20/12 takes precedence
• CPC Class Codes: B01J 2220/42 Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: C10L 10/00 Use of additives to fuels or fires for particular purposes additives for liquid carbonaceous fuels characterised by their chemical nature C10L1/10; using binders for briquetting solid fuels C10L5/10; using additives to improve the combustion of solid fuels C10L9/10
• CPC Class Codes: C10L 10/02 for reducing smoke development
• CPC Class Codes: C10L 9/10 by using additives
• CPC Class Codes: F23J 15/00 Arrangements of devices for treating smoke or fumes
• CPC Class Codes: F23J 15/025 : using filters
• CPC Class Codes: F23J 15/04 : using washing fluids scrubbers for removing solids only F23J15/022
• CPC Class Codes: F23J 7/00 : Arrangement of devices for supplying chemicals to fire
• CPC Class Codes: F23K 1/00 : Preparation of lump or pulverulent fuel in readiness for delivery to combustion apparatus
• CPC Class Codes: F23K 2201/505 : with additives
• CPC Class Codes: Y02P 40/10 : Production of cement, e.g. improving or optimising the production methods; Cement grinding
• CPC Class Codes: Y10S 423/05 : Automatic, including computer, control

Abstract

Sorbent compositions containing halogen and calcium are added to coal to mitigate the release of sulfur and/or other harmful elements, including mercury, into the environment during combustion of coal containing natural levels of mercury.

Claims

1. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel, wherein the sorbent composition comprises a halogen compound and a source of calcium;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of calcium addition according to the measured level of sulfur.

2. A method according to claim 1, wherein the sorbent composition comprises an inorganic source of bromine.

3. A method according to claim 1, wherein the sorbent composition comprises an organic bromine compound.

4. A method according to claim 1, wherein the sorbent composition comprises calcium oxide, calcium hydroxide, calcium carbonate, calcium bicarbonate, calcium sulfate, calcium bisulfate, calcium nitrate, calcium nitrite, calcium acetate, calcium citrate, calcium phosphate, or calcium hydrogen phosphate.

5. A method according to claim 1, wherein the sorbent composition comprises a calcium mineral.

6. A method according to claim 1, wherein the sorbent composition comprises an organic calcium compound.

7. A method according to claim 1, wherein the sorbent composition comprises a basic powder containing calcium.

8. A method according to claim 7, wherein the basic powder is selected from portland cement, cement kiln dust, and lime kiln dust.

9. A method according to claim 1, wherein the sorbent composition comprises an aluminosilicate clay.

10. A method according to claim 1, wherein the sorbent composition comprises an iodine compound.

11. A method according to claim 10, wherein the sorbent composition comprises an iodine containing salt of an alkali metal or an alkaline earth metal.

12. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises an organic halogen compound and a source of calcium.

13. A method according to claim 12, comprising measuring sulfur in the combustion gases and adjusting the rate of calcium added according to the measured level of sulfur.

14. A method according to claim 12, wherein the sorbent composition comprises calcium oxide, calcium hydroxide, calcium carbonate, calcium bicarbonate, calcium sulfate, calcium bisulfate, calcium nitrate, calcium nitrite, calcium acetate, calcium citrate, calcium phosphate, or calcium hydrogen phosphate.

15. A method according to claim 12, wherein the sorbent composition comprises a calcium mineral.

16. A method according to claim 12, wherein the sorbent composition comprises an organic calcium compound.

17. A method according to claim 12, wherein the sorbent composition comprises a basic powder containing calcium.

18. A method according to claim 17, wherein the basic powder is selected from portland cement, cement kiln dust, and lime kiln dust.

19. A method according to claim 12, wherein the sorbent composition comprises an aluminosilicate clay.

20. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises a halogen compound and a source of calcium selected from calcium oxide, calcium hydroxide, calcium carbonate, calcium bicarbonate, calcium sulfate, calcium bisulfate, calcium nitrate, calcium nitrite, calcium acetate, calcium citrate, calcium phosphate, and calcium hydrogen phosphate.

21. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises a halogen compound and an organic calcium compound.

22. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises a halogen compound and a basic powder selected from the group consisting of Portland cement, cement kiln dust, and lime kiln dust.

23. A method according to claim 22, comprising measuring sulfur in the combustion gases and adjusting the rate of calcium added according to the measured level of sulfur.

24. A method according to claim 22, wherein the sorbent composition comprises an inorganic source of bromine.

25. A method according to claim 22, wherein the sorbent composition comprises an organic bromine compound.

26. A method according to claim 22, wherein the sorbent composition comprises an aluminosilicate clay.

27. A method according to claim 22, wherein the sorbent composition comprises an iodine compound.

28. A method according to claim 27, wherein the sorbent composition comprises an iodine containing salt of an alkali metal or an alkaline earth metal.

29. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises a halogen compound and an aluminosilicate clay.

30. A method according to claim 29, wherein the sorbent composition comprises an inorganic source of bromine.

31. A method according to claim 29, wherein the sorbent composition comprises an organic bromine compound.

32. A method according to claim 29, wherein the sorbent composition further comprises calcium oxide, calcium hydroxide, calcium carbonate, calcium bicarbonate, calcium sulfate, calcium bisulfate, calcium nitrate, calcium nitrite, calcium acetate, calcium citrate, calcium phosphate, or calcium hydrogen phosphate.

33. A method according to claim 29, wherein the sorbent composition further comprises a calcium mineral.

34. A method according to claim 29, wherein the sorbent composition further comprises an organic calcium compound.

35. A method according to claim 29, wherein the sorbent composition further comprises a basic powder containing calcium.

36. A method according to claim 35, wherein the basic powder is selected from portland cement, cement kiln dust, and lime kiln dust.

37. A method according to claim 29, wherein the sorbent composition comprises an iodine compound.

38. A method according to claim 37, wherein the sorbent composition comprises an iodine containing salt of an alkali metal or an alkaline earth metal.

39. A method for reducing emissions of mercury arising from combustion of mercury containing fuels in a fuel burning facility, the method comprising:

applying a sorbent composition onto the fuel;

delivering the fuel with the sorbent composition applied into a furnace of the facility;

combusting the fuel with the sorbent composition in the furnace to produce combustion gases and ash;

removing the ash from the combustion gases by capturing it in a particulate removal system disposed in a convective pathway of the facility downstream of the furnace;

measuring the level of mercury and/or sulfur remaining in the combustion gases after capture of the ash; and

adjusting the rate of sorbent addition according to the measured level of mercury and/or sulfur,

wherein the sorbent composition comprises an iodine compound and a source of calcium.

40. A method according to claim 39, comprising measuring sulfur in the combustion gases and adjusting the rate of calcium added according to the measured level of sulfur.

41. A method according to claim 39, wherein the sorbent composition comprises calcium oxide, calcium hydroxide, calcium carbonate, calcium bicarbonate, calcium sulfate, calcium bisulfate, calcium nitrate, calcium nitrite, calcium acetate, calcium citrate, calcium phosphate, or calcium hydrogen phosphate.

42. A method according to claim 39, wherein the sorbent composition comprises a calcium mineral.

43. A method according to claim 39, wherein the sorbent composition comprises an organic calcium compound.

44. A method according to claim 39, wherein the sorbent composition comprises a basic powder containing calcium.

45. A method according to claim 44, wherein the basic powder is selected from portland cement, cement kiln dust, and lime kiln dust.

46. A method according to claim 39, wherein the sorbent composition further comprises an aluminosilicate clay.

47. A method according to claim 39, wherein the sorbent composition comprises an iodine containing salt of an alkali metal or an alkaline earth metal.