JPS63171816A - How to use oxygen blast furnace gas - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] "Purpose of invention" (Industrial application field) Technology for processing and utilizing blast furnace gas generated from oxygen blast furnaces.

(Prior Art) Advantageous operations can be achieved by injecting high-concentration oxygen through the blast furnace tuyeres, and such a method is described in JP-A-60-159104.

(Problem to be solved by the invention) Since the blast furnace gas generated from the conventional oxygen blast furnace as described above has a higher calorie content than the blast furnace gas generated from an ordinary blast furnace, this oxygen blast furnace gas can be used to recover and use ordinary blast furnace gas. cannot be used in the system.

On the other hand, operating the oxygen blast furnace described above requires a large amount of oxygen, and if such a large amount of oxygen is manufactured by conventional methods or purchased and used, the advantages of the oxygen blast furnace are significantly lost.

In addition, the entire amount of oxygen blast furnace gas is sent to a power plant to generate electricity,
Although it is conceivable to operate oxygen separation equipment using the obtained power generation, the equipment cost for this would be large, and furthermore, the cost would not necessarily be reduced.

"Structure of the Invention" (Means for Solving the Problems) The present invention was devised to solve the problems of the conventional products as described above, and it The combustion gas obtained by combustion is sent to a boiler to generate high-pressure steam, and the remainder of the oxygen blast furnace gas is partially combusted to reduce the calorie level to the calorie level of normal blast furnace gas, and the heat generated by the partial combustion is heat exchanged. to generate intermediate-pressure steam, drive a steam turbine with the intermediate-pressure steam and the high-pressure steam, and drive an oxygen separation plant with the output of the steam turbine to obtain oxygen and supply it to the oxygen blast furnace operation. This is a method of utilizing oxygen blast furnace gas.

(Function) A portion of the oxygen blast furnace gas produces high-pressure steam, which is the main component that drives the steam turbine. By partially combusting the remaining oxygen blast furnace gas, its calorie is reduced and a gas that can be used in the same way as normal blast furnace gas is obtained. Also, the heat generated by this partial combustion is exchanged to obtain intermediate pressure steam, which is used to drive the steam turbine.

Air is compressed by driving the steam turbine, and the compressed air is cooled to produce liquid air, which is then sent to a distillation column for treatment, whereby oxygen is separated and obtained.

The oxygen thus obtained is supplied to the oxygen blast furnace operation.

The outline of the equipment for carrying out the method of the present invention is as shown in the attached drawings. That is, the oxygen blast furnace gas 1 discharged from the top of the oxygen blast furnace 10 is guided to the coarser 2, and then a part of it is combusted in the combustor 3, and then supplied to the shaft again to be used as charging raw material. A portion of the boiler is sent to another boiler combustor 4 where it is blown by an air blower 5 and combusted. Exhaust gas from the combustor 4 is led to a boiler 6, which heats water in an adjacent steam turbine 7 to turn it into ultra-high pressure steam, which is then sent to the steam turbine 7 to drive it. The heat-exchanged exhaust gas from the boiler 6 is released from the chimney 9 into the outside air. As mentioned above, the surplus oxygen blast furnace gas other than that sent to the combustor 4 supplies oxygen and is reduced in calories in the partial combustor 11, and is then led to the heat exchanger 12, and then to the top gas generator 13. After that, it passes through a cooler 14 to the blast furnace gas storage and utilization line 1 along with normal blast furnace gas.
5, pipes from the steam turbine 7 are led to the heat exchanger 12 in the same way as the boiler 6, and the intermediate pressure steam obtained by the heat exchanger 12 is routed to the steam turbine 7.
It is introduced in the middle of the

An air compressor 8 is connected to the steam turbine 7, and the compressed air obtained by the air compressor 8 is cooled and liquefied in a refrigerator 18, and then introduced into a distillation column 19 where it is separated into N2 and at. Obtained O! The gas is led to the tuyere of the oxygen blast furnace 10 and used for its operation, and is also used for partial combustion in the partial combustor 11, and therefore the oxygen blast furnace gas is branched into the combustor 4 as described above. The amount of 1 is controlled as an amount commensurate with the required amount of oxygena.
It goes without saying that Nz gas can be used appropriately for well-known nitrogen gas applications.

(Example) To specifically explain the method of the present invention carried out using the above-mentioned equipment, ore, sintered ore, and coke are charged from the top of a blast furnace with a tapping capacity of 5000 tons/day, and The purity obtained from the distillation column 19 from the mouth is about 99.6.
% oxygen 6880ONrd/hr and pulverized coal 62500
A part of the top gas 11 of the oxygen blast furnace 10 (59,800 Nrrr/hr) was combusted in the combustor 3 and heated to 1,000°C and was blown into the shaft section for preheating. .

The remainder of the above-mentioned furnace top gas is supplied to the boiler combustor 4 at a rate of 110,000 Nrrr/hr, and the remainder 3
210 ONn? /hr was sent to the partial combustor 11 and operated to obtain blast furnace gas having a calorific value comparable to that of normal blast furnace gas. That is, in the boiler combustor 4, air of 160,000 Nrrr/hr is supplied to the gas from the blower 5 and combusted, and by sending this to the boiler 6,
100 kg/- of ultra-high pressure steam 6a at approximately 532°C is 200
This steam was generated at a rate of 1,000 kg/hr, and was sent to the steam turbine 7 to drive the steam turbine 7 together with intermediate pressure steam 12a, which will be described later. The steam turbine 7 operates an air compressor 8 to produce 642,000 Nrrr/hr of air.
It was compressed to about 5 kg/- and sent to a refrigerator 18 to be converted into liquid air, and then sent to a distillation column 19 to obtain Ol, N, and gas. 0. The gas amount is 14100ONrrr/hr,
Also, the Nt gas is 14000ONrrr/hr, and this 0. The majority of the gas, 6880ONrrr/hr, is sent to the oxygen blast furnace 10 as described above, and the remainder, 360ONrrr/hr, is sent to the oxygen blast furnace 10 as described above.
0 Nn? /hr was sent to partial combustor 11 as described above. The others were used in the converter equipment within the plant. On the other hand, the gas at about 298°C from the partial combustor 11 is heat exchanged in the heat exchanger 12 to obtain intermediate pressure steam of about 200°C and 12 kg/cd, which is supplied to the intermediate part of the steam turbine 7. The approximately 120°C gas discharged from the heat exchanger 12 is heated to approximately 150°C in the furnace top gas generator 13.
86000 Nrr as a gas on the level of normal blast furnace gas that generates 0 Kw/hr of electricity and then cools down in the cooler 14 and has a calorific value of 850 KcaJ/Nrrr.
I was able to get r/hr.

"Effects of the Invention" According to the present invention as explained above, the oxygen required in this type of oxygen blast furnace can be appropriately produced and supplied using a part of the oxygen blast furnace gas discharged from the top of the furnace. Therefore, it is possible to achieve a sufficient cost reduction in terms of equipment and operation, and the advantageous oxygen blast furnace operation can be carried out smoothly, so this invention is industrially very effective.

[Brief explanation of the drawing]

The drawings show the technical content of the present invention, and are explanatory diagrams showing an outline of equipment for implementing the method of the present invention. In this drawing, 1 is an oxygen blast furnace gas, 2 is a coarse powder, 3 is a combustor for preheating the blast furnace, 4 is a combustor for a boiler, 5 is a blower, 6 is a boiler, 7 is a steam turbine,
8 is an air compressor, 9 is a chimney, 10 is an oxygen blast furnace, 11 is a partial combustor, 12 is a heat exchanger, 13 is a top gas generator, 1
4 is a cooler, 15 is a blast furnace gas storage and utilization line, 18
1 is a refrigerator, and 19 is a distillation column.

Claims (2)

[Claims] (1) The combustion gas obtained by combusting a part of the gas generated from the oxygen blast furnace is sent to a boiler to generate high-pressure steam, and the remaining part of the oxygen blast furnace gas is partially combusted to bring the calorie level to that of normal blast furnace gas. At the same time, the heat generated by the partial combustion is exchanged to generate intermediate pressure steam, the intermediate pressure steam and the high pressure steam drive a steam turbine, and the output of the steam turbine drives an oxygen separation plant to remove oxygen. A method of utilizing oxygen blast furnace gas, characterized in that the oxygen blast furnace gas is supplied to the oxygen blast furnace operation. (2) The method for utilizing oxygen blast furnace gas according to claim 1, wherein the amount of oxygen blast furnace gas to be combusted to generate high-pressure steam is determined by the amount of oxygen required for the operation of the oxygen blast furnace.