Method for judging and treating furnace heat of hydrogen-rich carbon circulating oxygen blast furnace

Abstract

The invention belongs to the technical field of blast furnace ironmaking, and particularly discloses a method for judging and treating furnace heat of a hydrogen-rich carbon circulating oxygen blast furnace, which specifically comprises the following steps of: blowing hydrogen-rich coal gas and oxygen through a tuyere to realize a carbon reduction target, and comprehensively judging the furnace temperature trend through unit consumption of coal gas blown per ton iron, coal gas utilization efficiency, top temperature and unit consumption of oxygen during operation. By dynamically controlling unit consumption of injection coal gas, adjusting coke ratio and injection coal gas ratio according to coal gas utilization efficiency and controlling oxygen injection quantity, dynamic control of furnace heat is realized, and the target of stable operation of furnace conditions is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blast furnace ironmaking, in particular to a judgment and disposal method for furnace heat of a hydrogen-rich carbon-circulation oxygen blast furnace. BACKGROUND

[0002] Blast furnace ironmaking accounts for nearly 90% of the molten iron production capacity in China, and has made great contributions to the development of national economy and human civilization due to its high thermal efficiency and high production capacity. However, the carbon utilization efficiency of the blast furnace ironmaking process is low, less than 65% on average, which is the main reason for the high carbon emission of traditional blast furnace ironmaking. In order to achieve carbon emission reduction of blast furnace ironmaking, it is necessary to start from the ironmaking process and reduce carbon consumption in the ironmaking process to explore new energy-saving and carbon-reducing processes. The hydrogen-rich carbon-circulation oxygen blast furnace uses tuyere full-oxygen smelting, sprays decarburization coal gas and hydrogen-rich coal gas instead of traditional blast. Due to the particularity of the process, the hydrogen-rich carbon-circulation oxygen blast furnace is different from the traditional blast furnace in handling furnace heat. In the traditional blast furnace, the furnace heat is mainly adjusted by adjusting the solid fuel ratio of coke ratio or coal ratio. The hydrogen-rich carbon-circulation oxygen blast furnace realizes a reduction of 40% in fossil energy (coke ratio plus coal ratio) consumption, and the handling of furnace heat is not only the adjustment of solid fuel, but also the comprehensive judgment of furnace temperature trend through ton coal gas consumption, coal gas utilization efficiency, top temperature and oxygen consumption, and the dynamic control of coal gas consumption, coke ratio adjustment according to coal gas utilization efficiency, coal gas ratio and oxygen injection amount to realize dynamic control of furnace heat, and then achieve stable operation of furnace condition and carbon emission reduction target. SUMMARY

[0003] The purpose of the present application is to provide a judgment and disposal method for furnace heat of a hydrogen-rich carbon-circulation oxygen blast furnace, so as to comprehensively judge the furnace temperature trend and dynamically regulate the related parameters, and then achieve stable operation of furnace condition and carbon emission reduction target.

[0004] In order to achieve the above purpose, the basic scheme provided by the present application is: a judgment and disposal method for furnace heat of a hydrogen-rich carbon-circulation oxygen blast furnace, during the operation, the furnace temperature trend is comprehensively judged by monitoring ton iron injection coal gas consumption, coal gas utilization efficiency, furnace top temperature and oxygen consumption; the dynamic control of coal gas consumption, coke ratio adjustment according to coal gas utilization efficiency and coal gas ratio, and control of oxygen injection amount are used to realize the dynamic control of furnace heat.

[0005] Further, under the condition of stable fixed fuel ratio, the ton iron injection decarburization coal gas consumption increases, and the furnace temperature will rise; or when the furnace temperature is high, the injection amount is reduced to reduce the furnace temperature; wherein the replacement ratio of decarburization coal gas to coke is 0.16-0.18 kg / m 3 .

[0006] Further, when the fixed fuel ratio and injection coal gas consumption are stable, the coal gas utilization rate needs to be reduced by 4-6 kg / t for every 1% increase, otherwise the furnace temperature will be hot.

[0007] Further, when the top temperature continues to be lower than the top temperature reference value, the furnace temperature will be cool, and the decarburization coal gas injection amount should be sequentially increased by 50-80 m 3 / t, the hydrogen-rich coal gas injection amount is 30-50 m 3 / t, the coal injection amount is 10-15 kg / t, and finally the coke amount is increased by 2-5 kg / t; when the top temperature continues to be higher than the top temperature reference value for 1-2 hours, the decarburization coal gas and the hydrogen-rich coal gas injection amounts are each reduced by 50-80 m 3 / t; when it is higher than 2 hours, the coal injection amount and the coke amount are each reduced by 2-5 kg / t.

[0008] Further, when the furnace temperature continues to be too high, the tuyere oxygen injection amount is increased by 5%-10%, the hourly output is increased by 5%-8%, and the per-ton-iron coal gas consumption is reduced by 4%-6%, so as to make the furnace temperature descend; when the furnace temperature continues to be too low, the oxygen injection amount is reduced by 5%-10%, the hourly output is reduced by 5%-8%, and the per-ton-iron coal gas consumption is increased by 4%-6%, so as to make the furnace temperature ascend.

[0009] Further, the top temperature reference value is 100-120 DEG C.

[0010] Further, the fixed fuel ratio is the coke ratio plus the coal ratio.

[0011] Compared with the prior art, the present application has the following advantages: The present application precisely controls the blast furnace temperature and trend through an effective operation method, and adjusts the injection amounts of the decarburization coal gas and the hydrogen-rich coal gas through tuyere injection, so as to stabilize the furnace temperature or reduce the ratio. Meanwhile, due to the influence of the blast furnace high-reducing coal gas utilization rate on the furnace heat, the present application precisely proposes the adjustment direction and adjustment amount of the furnace heat after the coal gas utilization rate changes, which plays a key guiding role in the stable operation of the hydrogen-rich carbon cycle oxygen blast furnace and the realization of the decarburization target. DETAILED DESCRIPTION

[0012] The present application will be further described in detail through specific embodiments: A judgment and disposal method for the furnace heat of a hydrogen-rich carbon cycle oxygen blast furnace, during the operation, the furnace temperature trend is comprehensively judged by monitoring the per-ton-iron injected coal gas consumption, the coal gas utilization efficiency, the furnace top temperature and the oxygen consumption; the dynamic control of the injected coal gas consumption, the adjustment of the coke ratio and the injected coal gas ratio according to the coal gas utilization efficiency, and the control of the oxygen injection amount are used to realize the dynamic control of the furnace heat.

[0013] Under the condition of the fixed fuel ratio stability, the per-ton-iron injected decarburization coal gas consumption is increased, and the furnace temperature will be increased; or when the furnace temperature is relatively high, the injection amount is reduced to reduce the furnace temperature; wherein the replacement ratio of the decarburization coal gas and the coke is 0.16-0.18 kg / m 3 .

[0014] When the fuel ratio and the single consumption of injected gas are stable, the gas utilization rate is increased by 1%, and the coke ratio is decreased by 4-6 kg / t accordingly, otherwise the furnace temperature is increased. When the furnace temperature is continuously high, the oxygen injection amount of the tuyere is increased by 5%-10%, the hourly output is increased by 5%-8%, the single consumption of gas per ton of iron is decreased by 4%-6%, and the furnace temperature is decreased; when the furnace temperature is continuously low, the oxygen injection amount is decreased by 5%-10%, the hourly output is decreased by 5%-8%, the single consumption of gas per ton of iron is increased by 4%-6%, and the furnace temperature is increased.

[0015] When the top temperature is continuously lower than the top temperature reference value, the furnace temperature will be low, and the decarburization gas injection amount is increased by 50-80 m 3 / t, the hydrogen-rich gas injection amount is increased by 30-50 m 3 / t, the coal injection amount is increased by 10-15 kg / t, and finally the coke amount is increased by 2-5 kg / t; when the top temperature is continuously higher than the top temperature reference value for 1-2 hours, the decarburization gas injection amount and the hydrogen-rich gas injection amount are each decreased by 50-80 m 3 / t; when it is higher than 2 hours, the coal injection amount and the coke amount are each decreased by 2-5 kg / t, the top temperature reference value is 100-120℃, and the fixed fuel ratio is the coke ratio plus the coal ratio.

[0016] The above method is applied to the 430 hydrogen-rich carbon cycle oxygen blast furnace of Bayi Steel, and the implementation example is as follows: Example 1 During normal production of the 430 hydrogen-rich carbon cycle oxygen blast furnace, the coke ratio is 350 kg / t, the coal ratio is 50 kg / t, the hourly output is 70 t / h, the decarburization gas injection ratio is 650 m 3 / t, the coke oven gas injection ratio is 100 m 3 / t, the comprehensive gas injection ratio is 750 m 3 / h, and the oxygen single consumption of the blast furnace tuyere is 235 m 3 / t; during operation, the decarburization gas injection ratio is increased to 700 m 3 / t, without any parameter adjustment, the furnace temperature will be increased in the later period, and in actual operation, the coke ratio is adjusted by 10 kg / t, and the decarburization gas replacement ratio is 0.2 kg / t.

[0017] Example 2 During normal production of the 430 hydrogen-rich carbon cycle oxygen blast furnace, the coke ratio is 350 kg / t, the coal ratio is 50 kg / t, the decarburization gas injection ratio is 650 m 3 / t, the coke oven gas injection ratio is 100 m 3 / t, the comprehensive gas injection ratio is 750 m 3 / h, and the oxygen single consumption of the blast furnace tuyere is 235 m 3 / t; during operation, the furnace temperature is continuously high, and in actual operation, the oxygen is increased by 2000 m3 / h, which is equivalent to an increase of 8.5 t / h in hourly output and a decrease of 668.7 m 3 / h, and the later furnace temperature will decrease.

[0018] Example 3 430rich hydrogen carbon cycle oxygen blast furnace in normal production period, coke ratio is 350kg / t, coal ratio is 50kg / t, injection of decarburization gas ratio is 650m 3 / t, injection of coke oven gas ratio is 100m 3 / t, the comprehensive injection gas ratio is 750m 3 / h, the oxygen consumption of blast furnace tuyere is 235m 3 / t; during operation, the gas utilization rate CO2 / (CO+C02) increases by 1%, if nothing is done, the furnace temperature will increase, in actual operation, the coke ratio is adjusted from 350kg / t to 345kg / t, the stable furnace temperature is maintained, and the coke ratio is also reduced.

[0019] Example 4 430rich hydrogen carbon cycle oxygen blast furnace in normal production period, coke ratio is 350kg / t, coal ratio is 50kg / t, injection of decarburization gas ratio is 650m 3 / t, injection of coke oven gas ratio is 100m 3 / t, the comprehensive injection gas ratio is 750m 3 / h, the oxygen consumption of blast furnace tuyere is 235m 3 / t; during operation, the furnace temperature is continuously low, in actual operation, the decarburization gas is increased by 100m 3 / t, or the coke oven gas is increased by 50m 3 / t, to increase the furnace temperature, the tuyere coal injection ratio can also be increased by 30-50kg / t, if the above measures are implemented, and the furnace temperature is still low, the coke ratio is increased by 5-10kg / t.

[0020] The above is only an embodiment of the present application, and the specific structure and characteristics of the scheme are not described in detail. It should be noted that for those skilled in the art, without departing from the structure of the present application, a number of modifications and improvements can be made, which should also be considered as the protection scope of the present application, which will not affect the effect and practicality of the patent. The protection scope claimed in this application should be subject to the content of its claims, and the specific implementation mode and the like recorded in the specification can be used to explain the content of the claims.

Claims

1. A method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace, characterized in that: During operation, the furnace temperature trend is comprehensively judged by monitoring the unit consumption of pulverized gas per ton of iron, gas utilization efficiency, furnace top temperature and oxygen consumption. Dynamic control of furnace heat is achieved by dynamically adjusting the unit consumption of injected pulverized gas, adjusting the coke ratio and the ratio of injected pulverized gas based on the gas utilization efficiency, and controlling the amount of oxygen injected.

2. The method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to claim 1, characterized in that, Under a stable fuel ratio, an increase in the consumption of decarburized gas per ton of iron injection will lead to a rise in furnace temperature; alternatively, when the furnace temperature is high, the injection rate can be reduced to lower the furnace temperature. The replacement ratio of decarburized gas to coke is 0.16-0.18 kg / m³. 3 .

3. The method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to claim 1, characterized in that, When the fixed fuel ratio and the unit consumption of injected pulverized gas are stable, for every 1% increase in gas utilization rate, the coke ratio needs to be reduced by 4-6 kg / t accordingly; otherwise, the furnace temperature will rise.

4. The method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to claim 1, characterized in that, When the top temperature remains below the reference value, the furnace temperature will cool down, and the decarbonization gas injection rate should be increased by 50-80 m³ in sequence. 3 / t, hydrogen-rich coal gas injection rate 30-50m³ 3 The coal injection rate is 10-15 kg / t, with a final increase of 2-5 kg / t for coke. When the top temperature remains above the benchmark value for 1-2 hours, reduce the injection rates of decarbonized gas and hydrogen-rich gas by 50-80 m³ / t each. 3 / t; When the time exceeds 2 hours, reduce the amount of pulverized coal and coke by 2-5 kg / t.

5. The method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to claim 1, characterized in that, When the furnace temperature remains high, increase the oxygen injection volume at the tuyeres by 5%-10%, increase the hourly output by 5%-8%, and reduce the gas consumption per ton of iron by 4%-6%, thereby causing the furnace temperature to drop. When the furnace temperature remains low, reduce the oxygen injection volume by 5%-10%, reduce the hourly output by 5%-8%, and increase the gas consumption per ton of iron by 4%-6%, thereby causing the furnace temperature to rise.

6. The method for judging and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to claim 4, characterized in that, The top temperature reference value is 100-120℃.

7. A method for determining and handling heat in a hydrogen-rich carbon-circulating oxygen blast furnace according to any one of claims 3, 4, or 6, characterized in that, The fixed fuel ratio is the coke ratio plus the coal ratio.