Claims
- 1. A process for treating coal in an inert atmosphere to increase its rank, comprising the steps of:(a) heating coal at 200-250° F. to produce coal virtually free of surface moisture; (b) heating the coal produced in step (a) to a temperature of 400-750° F. in an inert atmosphere for about 2-4 minutes to produce coal having a moisture content of between 2-5%; (c) heating the coal produced in step (b) to a temperature of about 900-1100° F. in an inert atmosphere for up to about 5 minutes to produce coal having a moisture content of 1-2% and mass reduction of up to 50%; (d) heating the coal produced in step (c) to a temperature of 1300-1550° F. in an inert atmosphere for about 2-4 minutes, to produce coal having a moisture content of less than 2% and volatiles content of less than 25%; (e) heating the coal produced in step (d) to a temperature of about 2000-2400° F. in an inert atmosphere for 2-4 minutes, to produce coal having a moisture content of less than 2% by weight and a volatiles content of 15% or less by weight; (f) cooling the coal produced in step (e) by exposing to a cooling gas which is substantially free of oxygen-and moisture to form treated coal; and (g) collecting the treated coal.
- 2. A process according to claim 1, wherein in step (f) the coal is cooled by exposing the coal to a dry cooling gas.
- 3. A process according to claim 2, wherein the cooling gas is substantially free of oxygen.
- 4. A process according to claim 2, wherein the cooling gas has a moisture content of less than 1% by weight.
- 5. A process according to claim 1, wherein the inert atmosphere is selected from the group consisting of steam, nitrogen and liquid hydrocarbons.
- 6. A process according to claim 1, wherein the inert atmosphere is nitrogen and liquid hydrocarbons.
- 7. A process according to claim 5, wherein the liquid hydrocarbons have a formulae ranging from CH4 to C8H18.
- 8. A process according to claim 1, wherein said coal is selected from peat, lignite, sub-bituminous coal, bituminous coal and anthracite coal.
- 9. A process according to claim 1, wherein the treated coal has a BTU content of 12,500 BTU/lb. or higher.
- 10. A process according to claim 1, wherein prior to step (b), coal produced in step (a) is crushed to produce coal having a top size of about 2 inches.
- 11. A process according to claim 10, wherein the coal prior to crushing is subjected to a preliminary drying step to reduce the surface moisture content.
- 12. A process according to claim 10, wherein he crushed coal is subjected to a drying step by heating to a temperature in the range of 200-250° F. for a period of about 5 minutes in order to remove the surface moisture.
- 13. A process according to claim 1, wherein ¼″ and less treated coal that is collected is formed into briquettes and provided with a waterproof binder/igniter/coating.
- 14. A treated coal produced according to the process of claim 1.
- 15. The treated coal according to claim 14, further provided with a waterproof binder/igniter/coating.
- 16. The Treated coal according to claim 14 further formed into briquettes.
- 17. The briquettes according to claim 16 further provided with a water-proof binder/igniter/coating.
Parent Case Info
This application claims the benefit of U.S. provisional application No. 60/163,566, filed Nov. 5, 1999.
US Referenced Citations (8)
Provisional Applications (1)
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Number |
Date |
Country |
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60/163566 |
Nov 1999 |
US |