A treatment method for reducing and stopping oxygen time in blast furnace heavy-duty high-oxygen-enriched smelting

Abstract

The invention discloses a treatment method for reducing and stopping oxygen in heavy-duty high-oxygen smelting of a blast furnace. It is mainly aimed at the smelting conditions of heavy load (coke load 5.30-5.95), high oxygen enrichment (oxygen enrichment rate 5.0-6.5%), and large coal ratio (coal ratio 155-205kg / t). Oxygen (oxygen enrichment rate reduction greater than 50%) post-blast furnace operation method. Mainly include: when the blast furnace is smelted under high oxygen-enriched conditions, when there is a sudden and large oxygen reduction, the control of blast humidity, blast temperature and blast volume; the control of coke load and smelting intensity; the control of blast furnace coal injection; Gas flow distribution control. According to the operation method of the present invention, the impact of the large oxygen reduction of the blast furnace on the blast furnace smelting can be effectively reduced, and the impact of the output loss of the blast furnace and the fluctuation of the furnace condition on the service life of the main equipment of the blast furnace can be reduced.

Description

technical field [0001] The present application relates to the technical field of blast furnace smelting, in particular to a treatment method for reducing and stopping oxygen under heavy-duty high-oxygen smelting in a blast furnace. Background technique [0002] High oxygen-enriched smelting is one of the most important characteristics of today's modern large-scale blast furnace smelting, which to a certain extent represents the characteristics of enhanced smelting level and technological progress. With the development of large-scale domestic blast furnaces, blast furnace high oxygen-enriched smelting technology has been greatly developed. ) normalized production. [0003] However, if a large oxygen reduction occurs under this high-level smelting state, it will have a great impact on the blast furnace smelting system, which is mainly reflected in: [0004] 1) Affect the hearth temperature. A high oxygen enrichment rate is conducive to increasing the theoretical combustion ...

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Problems solved by technology

[0005] 2) Oxygen-enriched blast will increase the content of CO and H2 in the gas

When the oxygen enrichment is reduced or stopped, the air volume consumed by the production unit iron volume increases, resulting in an increase in the bosh gas volume, which affects the pressure-volume relationship in the furnace. If it is not handled properly, it will cause fluctuations in furnace conditions

[0006] 3) Reduce or stop oxygen enrichment, resulting in a decrease in the oxygen content in the blast, which will affect the fuel rate of the blast furnace pulverized coal, resulting in a decrease in the blast furnace coal ratio, and affect the smelting strength of the blast furnace

[0007] At present, there is no written operation specification and standard for large-scale blast furnace heavy-duty high-oxygen-enriched smelting to greatly reduce oxygen. If the blast furnace does not respond well, it will often cause unstable gas flow and abnormal furnace conditions, which will greatly affect pig iron production, quality and other major items. Indicators, the main economic indicators of the blast furnace have regressed sharply, seriously threatening the normal production of the blast furnace

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