An iron-making process for efficient recycling of blast furnace top gas

Abstract

Provided is an iron smelting process achieving effective and cyclic utilization of stock gas of a blast furnace. The reduction potential of the stock gas of the blast furnace is fully utilized for performing prereduction on sintering ore, with high temperature, of the tail of a sintering machine so as to eliminate reduction degradation of the sintering ore in the blast furnace and improve the metallurgical performance of furnace charges put into the furnace. A sintering circular cooler is replaced with a vertical sintering ore prereduciton and cooling furnace, waste heat of the sintering ore is effectively recycled, and the sintering energy consumption is reduced. Coal gas circulates from the blast furnace to a dust remover, a pressure device, the vertical sintering ore prereduciton and cooling furnace, a waste heat recovery device, the presure device, a gas making converter, the pressure device and the blast furnace. According to the sintering ore reduction and cooling process, the finished sintering ore at the machine tail passes through a hot crusher, the vertical sintering ore prereduciton and cooling furnace and a sintering ore whole-grain screening device and is conveyed to top charging equipment of the blast furnace.

Description

technical field [0001] The invention relates to the technical field of ferrous metallurgy, in particular to a new energy-saving and emission-reducing technology for efficiently recycling blast furnace top gas to reduce sinter, recover waste heat from sinter and reform gas. It is suitable for blast furnace ironmaking process. Background technique [0002] 1. Waste heat recovery in sintering process [0003] In 2015, China's pig iron production was 691.4 million tons, accounting for 58.89% of the world's pig iron production; steel energy consumption was 380 million tce, accounting for about 13% of the country's total energy consumption. Blast furnace process energy consumption and CO 2 The emissions accounted for 49.0% and 53.0% of the iron and steel industry respectively. It can be seen that energy saving and emission reduction in the blast furnace process is very important to the economic and social development of our country; [0004] In the sinter production process, t...

AI Technical Summary

Problems solved by technology

It is estimated that the loss of power generation due to air leakage in the upper part accounts for 27.3% of the existing power generation, which increases the energy consumption of the sintering process by 1.25~1.56kgce, and the air leakage in the lower part increases the energy consumption of the sintering process by 0.25~0.27kgce;

[0006] 2) Sinter waste heat recovery rate is low

[0007] 3) The quality of cooling exhaust gas is low, and secondary pollutants appear

Under the current technical conditions, the use of blast furnace top gas injection technology will increase the cost of ironmaking

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