Process for realizing low-cost denitration by utilizing waste heat of sintered ores to heat sintering waste gas

Abstract

The invention provides a process for realizing low-cost denitration by utilizing waste heat of sintered ores to heat waste gas. According to the process, flue gas with relatively high NOx concentration in flue gas of a sintering machine is used as a cooling medium to be input into a cooling system for cooling the sintered ores, the part of the flue gas of the sintering machine can be heated to 260-480 DEG C after passing through the cooling system, then the part of the flue gas is input into a denitration system for denitration treatment, then waste heat utilization, dust removal and desulfurization treatment are carried out, and then the emission requirement is met; flue gas with relatively low NOx concentration in the flue gas of the sintering machine undergoes the desulfurization treatment after undergoing the waste heat utilization and the dust removal, and the emission requirement can be met directly, so that the flue gas treatment amount of the denitration system is reduced; andtherefore, the waste heat of the sintered ores in the cooling system is effectively utilized in the process, then the sintering flue gas can reach the required temperature in the denitration system, energy conservation and emission reduction are achieved, and meanwhile, the operation cost of sintering flue gas treatment is reduced.

Description

technical field [0001] The invention relates to a sintering flue gas denitrification process, in particular to a process for realizing low-cost denitrification by using sinter waste heat to heat sinter waste gas, and belongs to the fields of sinter sintering and waste heat utilization. Background technique [0002] The iron and steel industry is the foundation and pillar industry of my country's national economy. my country's iron and steel smelting is mainly based on the long process of "sintering (pellet) coking-blast furnace-converter". More than 75% of the blast furnace charge comes from sintering ore, and the annual output has reached nearly 1 billion tons, it can be seen that sintering production plays a vital role in the preparation of raw materials before ironmaking. At the same time, the sintering process is also a high energy consumption and high pollution concentrated link in the iron and steel process. SO x , NO x , persistent organic compounds, heavy metals an...

AI Technical Summary

Problems solved by technology

[0005] In order to reduce the total amount of sintering flue gas terminal treatment, improve the utilization rate of residual energy in the sintering system, and solve the long-standing problem of high operating cost of SCR technology applied to sintering denitrification, the present invention provides a process for denitrification by using sinter waste heat to heat sintering waste gas , the NO in the flue gas of the sintering machine x The flue gas with high concentration is input into the cooling system as the cooling medium to cool the sintering ore. After passing through the cooling system, the flue gas of this part of the sintering machine can be heated up to 260-480 °C, and then this part of the flue gas is input into the denitrification system for denitrification treatment, and then Carry out waste heat utilization, dust removal, and desulfurization treatment to meet the emission requirements; at the same time, NO in the flue gas of the sintering machine x Flue gas with a low concentration can directly meet the emission requirements after being desulfurized by waste heat utilization and dust removal, thereby reducing the processing capacity of the denitrification system

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