Claims
- 1. A method for burning a pulverized carbonaceous material containing sulfur and ash, comprising forming a slurry containing the carbonaceous material, water, a reagent adapted to react with the sulfur and a cementing agent, burning the slurry in a first stage with less than 100% theoretical air, removing the combustible gases from the first stage to a second stage, and burning the gases in the second stage with additional air.
- 2. The method of claim 1 wherein the slurry is burned in the first stage at a temperature below about 1100.degree. C.
- 3. The method of claim 1 wherein the slurry is burned in the first stage at a temperature between about 850.degree. C. and 1050.degree. C.
- 4. The method of claim 1 wherein the amount of water in the slurry is not more than 45% by weight.
- 5. The method of claim 1 wherein the cementing agent is calcium oxide.
- 6. The method of claim 1 wherein the amount of reagent in the slurry is not less than the stoichiometric amount necessary to react with the sulfur.
- 7. The method of claim 1 wherein the reagent is selected from the group consisting of calcium oxide, calcium carbonate, dolomite, magnesium oxide, sodium carbonate, sodium bicarbonate, clay and mixtures thereof.
- 8. The method of claim 1 wherein the reagent is adapted to reduce the melting temperature of the ash.
- 9. The method of claim 1 wherein the reagent is adapted to increase the melting temperature of the ash.
- 10. The method of claim 1 wherein the air in the first stage is introduced at a velocity of at least 0.3 meters/sec.
- 11. The method of claim 1 wherein the slurry contains a particulate binding agent.
- 12. The method of claim 11 wherein the amount of binding agent in the mixture is at least 2% by weight.
- 13. The method of claim 11 wherein the binding agent is selected from the group consisting of clay, sucrose, calcium acetate, acetic acid and mixtures thereof.
- 14. A method of burning a pulverized carbonaceous material containing sulfur and ash, comprising forming a slurry containing between 45% and 65% by weight of the carbonaceous material, between 30% and 45% by weight water and between 5% and 15% by weight calcium oxide, allowing the slurry to harden by reaction of the water with the calcium oxide, burning the slurry in a first stage with less than 100% theoretical air, removing the products of combustion from the first stage to a second stage, and burning the products in the second stage with additional air.
- 15. The method of claim 14 wherein the slurry is allowed to harden for about one hour.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. Patent Application Ser. No. 47,004, filed June 11, 1979, now U.S. Pat. No. 4,232,615.
US Referenced Citations (11)
Non-Patent Literature Citations (1)
Entry |
A Comprehensive Treatise on Inorganic and Theoretical Chemistry by J. W. Mellor, vol. X, S18, pp. 282-284, "The Alkaline Earth Sulphites". |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
47004 |
Jun 1979 |
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