Patent EA-002712-B1 (EA)
Title: Blast furnace with narrowed top section and method of using
Inventor: CLAFLIN H BRUCE
IPC: C10G1/00
Filed: 1999-07-23
Abstract: 1. In a blast furnace for processing a charge of material introduced into the top of the blast furnace, the material being heated as it moves downwardly through the widening, tapered stack of the blast furnace, the improvement wherein the stack has a narrowed top section which comprises approximately 15% of the stack height above the bosh and has a substantially constant diameter on the order of approximately 75% of the diameter that the uppermost portion of the stack would have if the taper of the stack were maintained substantially constant. 2. A blast furnace according to claim 1, wherein the stack has a tapered transition section which interconnects said top section and the remainder of the stack, said transition section comprising approximately 10% of the stack height above the bosh. 3. A blast furnace according to claim 2, further comprising five sets of tuyeres, two of said sets of tuyeres being located in the bosh and three of said sets of tuyeres being located in the stack above the bosh. 4. A blast furnace according to claim 3, wherein tuyere set T1 is located in the hearth above where molten slag and metal are allowed to collect, tuyere set T2 is located above tuyere set T1, tuyere set T3 is located above tuyere set T2 and above the mantel, tuyere set T4 is located above the mantel approximately 25% of the distance between the mantel and the top of the stack, and tuyere set T5 is located approximately 42% of the distance between the mantel and the top of the stack. 5. A blast furnace according to claim 4 including endothermic material injection system located at tuyere set T1 openings and oxygen jet nozzles and an endothermic injection system located at tuyere set T2. 6. A blast furnace according to claim 4 including sensing devices at the top, all five tuyere sets and the crucible to sense temperatures at all locations and obtain gas analysis at tuyere sets T3, T4, and T5 and the top. 7. A method of operating the blast furnace of claim 4 as a converter comprising the steps of: a. charging into the top the solid materials to be converted including carbonaceous materials said material moving downwardly through the stack forming a carbonaceous grate in the bosh; b. injecting through tuyere sets T1 and T2 all incoming gases, liquids and dusts; c. introducing 100% oxygen jet blast streams (with a small peripheral content of endothermic reacting material) through jet nozzles located in tuyere set T2 at a pressure high enough to enable them to penetrate deeply into the bosh in front of tuyere set T2; d. combusting in the bosh in front of tuyere set T2 carbon from the carbonaceous grate at high flame temperatures to furnish the process heat required to convert all input materials into a gas, vapor, molten metal, motel slag or dusts; e. introducing through tuyere set T1 endothermic reacting materials at a pressure slightly greater than that prevailing in the bosh to maintain a zone controlled temperature profile and create a temperature controlled buffer zone located between the high temperature more central portion of the bosh and the walls in the lower part of the converter to protect the refractories, the tuyeres, and injection systems located there from the high flame temperatures employed in the central portion of the bosh; f. withdrawing gases, vapors and dusts through tuyere sets T3, T4 and T5 to remove products and by-products and achieve zone control of the converter's temperature profile; g. withdrawing slag from the lower portion of the converter; h. withdrawing metal from near the bottom of the converter; and i. regulating the volume of endothermic reacting materials input through tuyere sets T1 and T2 and/or regulating the O2 input through tuyere set T2 to control the temperature in the bosh. 8. The method according to claim 7 wherein gases withdrawn from tuyeres T3, T4 and/or T5 and the top are conducted through waste heat boilers and sulfur removal systems to provide cleaned gases. 9. The method according to claim 8 wherein at least a portion of said cleaned gases are conducted to a synthetic polymer facility. 10. The method according to claim 7 wherein the molten slag is incorporated into building materials. 11. A method according to claim 7 wherein said carbonaceous material comprises non-premium coal and other non-premium carbonaceous materials. 12. A method according to claim 7, further comprising the step of employing a computer using input from sensing equipment located at T3, T4, T5 and the top gaseous stream to regulate the materials injected through tuyere sets T1 and T2 to maintain a temperature controlled protective zone between the high temperature central portion of the bosh and the refractory walls of the converter in the bosh. 13. A method according to claim 7 comprising the steps of: a. introducing a charge containing oil shales or oil sands in which the carbonaceous material per ton of oil shale or oil sands will be within a ratio of about 0.6 to 1.2; b. introducing endothermic reacting materials through tuyere set T1; c. introducing oxygen and an additional peripheral layer of endothermic reacting material through tuyere set T2; d. burning the carbonaceous grate material in said charge in the central portion of the bosh to produce the heat required to convert the down moving charge to gases, vapors, molten metal, molten slag or dusts and to provide heat for steps "e." and "f"; e. heating the charge near the top of stack, where the reduced diameter of the stack starts to taper to the conventional diameter to not above 480 degree C. to start releasing liquid kerogen and expanding the oil shale portion of the charge; f. further heating the charge at the bottom end of stack to approximately 1000 degree C. to convert the carbonaceous portion of the charge to coke or char and preheat the noncarbonaceous portion of the burden; g. further heating the down moving charge in the central portion of the bosh high enough to convert it to gases, molten slag, molten metal, vapors or dusts; h. removing molten metal and molten slag from the crucible; i. continuously withdrawing gases through tuyere set T3 containing recycling materials; j. withdrawing useful hydrocarbon gases and kerogen through tuyere sets T4 and T5, and through the top of the stack. 14. The method according to claim 13 wherein at least a portion of the withdrawn cases are conducted to a synthetic polymer plant. 15. The method according to claim 13 wherein the slag is incorporated into building materials. 16. The method according to claim 13 wherein at least a portion of the withdrawn gases is used for fuel. 17. A method according to claim 7 to convert municipal and/or industrial wastes having a metallic content into useful byproducts, the method comprising the steps of: a. introducing a charge containing said wastes, carbonaceous material and slag-forming constituents into the top of the furnace; b. introducing endothermic reacting materials through tuyere set T1; c. introducing oxygen through tuyere set T2; d. burning the carbonaceous material in said charge in the central portion of the bosh to melt slag therein and to provide heat for step (e); e. heating the charge in the stack to approximately 1,000 degree C. to convert the carbonaceous portion of the charge to coke or char and convert the noncarbonaceous portion to gases, vapors and molten materials; f. removing molten metal and molten slag from the crucible; g. withdrawing useful gases through tuyere set T3 having an energy content of 280 to 300 Btu/cf; and h. withdrawing useful gases through tuyere sets T4 and T5, and through the top of the stack. 18. The method of claim 17 wherein at least a portion of the withdrawn gases is used for fuel. 19. The method of claim 7 wherein the charge at the top of the converter contains metallic oxides. 20. The method of claim 7 wherein carbonaceous material of biomass origin is input to the top of the converter.