Production of cementitious ash products with reduced carbon emissions

• US 20070184394A1
• Filed: 02/05/2007
• Published: 08/09/2007
• Est. Priority Date: 02/07/2006
• Status: Abandoned Application

• Current Assignee: Nox Ii Ltd. (Arthur J Gallagher & Company)
• Original Assignee: Nox Ii Ltd. (Arthur J Gallagher & Company)
• Inventors: Comrie, Douglas C.
• Application Number:
  US11/702,477
• Publication Number:
  US 20070184394A1
• Time in Patent Office: Days
• US Class Current: 431/2
• CPC Class Codes: C04B 18/06 Combustion residues, e.g. purification products of smoke, fumes or exhaust gases
• CPC Class Codes: C04B 18/162 Cement kiln dust; Lime kiln dust
• CPC Class Codes: C04B 7/364 Avoiding environmental pollution during cement-manufacturing
• CPC Class Codes: C04B 7/367 Avoiding or minimising carbon dioxide emissions
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

The use of the cementitious ash in building products as total or partial replacement for Portland cement results in reduced carbon dioxide emissions that would otherwise result form the manufacture of Portland cement. In addition to avoided carbon dioxide emissions from calcining of limestone to make Portland cement and the burning of fossil fuels to provide the energy needed to make Portland cement, use of the sorbent components tends to increase the efficiency of energy production from burning of coal, further reducing greenhouse emissions from the burning of fossil fuel to produce energy.

Claims

1. A method of increasing the value of coal burned in a coal burning facility, the method comprising:

combusting coal containing mercury, without a flue gas desulfurization device and in a presence of at least one sorbent, to produce heat energy, ash, and flue gases; and

monitoring said flue gases for sulfur and mercury and adjusting said presence of said at least one sorbent to produce at least one of a sulfur emission and a mercury emission that is in compliance with an environmental regulation, thereby realizing a monetary savings by an avoidance of costs associated with said flue gas desulfurization device.

2. The method according to claim 1 further comprising reflecting said monetary savings on one or more financial statements.

3. The method according to claim 2, wherein said financial statements are at least one of a tax return, a balance sheet, a cash flow analysis, a shareholder equity statement, and an income statement.

4. The method according to claim 6 further comprising creating at least one of a carbon dioxide emission credit, a mercury emission credit, and a sulfur dioxide emission credit.

5. The method according to claim 4 further comprising reflecting said emission credit on one or more financial statements.

6. The method according to claim 1, wherein said ash contains at least 90% by weight of mercury originally present in said coal, said ash having an amount of acid leachable mercury that is less than a level of acid leachable mercury in an ash produced by combusting coal without said at least one sorbent.

7. The method according to claim 6 further comprising using said ash in the production of cement.

8. The method according to claim 6 further comprising selling said ash as an industrial raw material.

9. The method according to claim 1, wherein said at least one sorbent comprises at least one of CaO, SiO₂, Al₂O₃, Fe₂O₃, Na₂O, and K₂O.

10. The method according to claim 1, wherein said coal burning facility is an electric utility plant.

11. The method according to claim 1, wherein said coal burning facility is a cement plant.

12. The method according to claim 1, wherein said monetary savings from said presence of said at least one sorbent is greater than a cost of said presence of said at least one sorbent.

13. A method of operating a coal burning plant to produce energy and waste ash, the method comprising:

burning coal in the presence of a sorbent composition to produce a waste ash having improved cementitious properties as reflected in a strength activity index of said waste ash when compared to a waste ash produced from burning coal without said sorbent composition;

recovering said waste ash having cementitious properties, said waste ash having a reduced level of acid leachable mercury as compared to a waste ash produced from burning coal without said sorbent composition; and

producing a cement product from said waste ash.

14. The method according to claim 13 further comprising creating at least one of a carbon dioxide emission credit, a mercury emission credit, and a carbon dioxide emission credit.

15. The method according to claim 13, wherein said sorbent composition comprises at least one of CaO, SiO₂, Al₂O₃, Fe₂O₃, Na₂O, and K₂O.

16. The method according to claim 13, wherein the coal burning plant is a cement manufacturing plant.

17. The method according to claim 16 further comprising increasing a maximum production of cement by at least 25% and maintaining carbon dioxide emission under a carbon dioxide cap.

18. The method according to claim 16 further comprising maintaining a cement production level and selling carbon dioxide emission credits.

19. A method of operating a coal burning plant to produce heat energy and waste ash, the method comprising:

burning coal in the presence of at least one sorbent that increases an amount of a heavy metal in the waste ash and that decreases an acid leachable amount of said heavy metal in the waste ash when compared to said burning coal without said at least one sorbent;

selling the waste ash as an industrial raw material;

creating at least one of a mercury emission credit, a carbon dioxide emission credit, and a sulfur dioxide emission credit; and

selling said emission credit.

20. The method according to claim 19, wherein said at least one sorbent comprises at least one of CaO, SiO₂, Al₂O₃, Fe₂O₃, Na₂O, and K₂O.

21. A method of decreasing carbon dioxide emission from a coal burning cement manufacturing facility, the method comprising:

burning coal in the presence of at least sorbent to create energy, flue gas, and ash, said ash having cementitious properties as reflected in a strength activity index of said waste ash as compared to an ash from burning coal not in the presence of said at least one sorbent;

using said energy in manufacturing cement;

adding said ash having cementitious properties to said cement; and

increasing an amount of said cement produced without increasing an amount of limestone used in said manufacturing cement.

22. The method according to claim 21 further comprising creating at least one of a carbon dioxide emission credit, a mercury emission credit, and a sulfur dioxide emission credit.

23. The method according to claim 21, wherein said coal comprises mercury and said ash having cementitious properties comprising a greater amount of mercury as compared to said ash from burning coal not in the presence of said at least one sorbent.

24. The method according to claim 23, wherein said ash having cementitious properties containing at least 90% by weight of mercury originally present in said coal, said ash having an amount of acid leachable mercury that is less than a level of acid leachable mercury in said ash from burning coal not in the presence of said at least one sorbent.

25. Method of reducing the mercury emissions involved in production of cement, comprising:

combusting coal in the presence of a sorbent composition to produce heat energy;

using said heat energy to produce Portland cement by calcining limestone;

wherein the sorbent comprises calcium, silica, and alumina, and use of the sorbent results in lower emissions of mercury compared to burning the coal without the sorbent.

26. The method according to claim 25 producing a cementitious waste ash.

27. The method according to claim 26 increasing an output of the production of cement by adding said cementitious ash to said Portland cement.

28. The method according to claim 26, wherein said cementitious waste ash contains at least 90% by weight of mercury originally present in said coal, said ash having an amount of acid leachable mercury that is less than a level of acid leachable mercury in an ash produced by combusting coal without said at least one sorbent.