Steel smelting device capable of circularly spraying and blowing CO2 and CO-Ar in exhaust gas of VOD (Vacuum Oxygen Decarburization) furnace

Abstract

The invention discloses a steel smelting device capable of circularly spraying and blowing CO2 and CO-Ar in exhaust gas of a VOD (Vacuum Oxygen Decarburization) furnace. The device comprises a VOD furnace and an exhaust gas circulating treating device; the exhaust gas circulating treating device comprises a gas analyzing instrument, an exhaust gas switching device, a gas filtering dehydrating device, a gas compressing separating device, a CO2 gas storage tank, a CO2 flow control valve group, a CO-Ar mixed gas storage tank and a CO-Ar mixed gas flow control valve group; the exhaust gas is fed to the gas separating device by utilizing a vacuum pump; the gases, such as CO, CO2 and Ar, are separated from the exhaust gas by adopting a pressure swing adsorption method or a chemical adsorption method. The recycled CO2 and O2 are mixed and are applied to top blowing decarbonizing of the VOD furnace; the CO-Ar mixed gas is circulated and is used for bottom blowing stirring of the VOD furnace; the emission of greenhouse gas, namely the CO2, is reduced, and meanwhile, resource utilization of the CO2 is realized; the VOD treatment time is shortened; the alloy element yield rate is improved; the consumption of the Ar gas is reduced; the cost is reduced; great economic benefit is produced.

Description

technical field [0001] The invention belongs to the field of iron and steel metallurgy, and relates to CO in VOD furnace tail gas 2 , CO-Ar circulation injection steelmaking device. Background technique [0002] At present, VOD vacuum refining furnace is one of the vacuum refining equipment in steel production. It smelts low-carbon or ultra-low-carbon steel, mainly but not limited to stainless steel production. The production process of the traditional VOD vacuum refining furnace is as follows: ① first seal the ladle in the vacuum chamber, use an air pump to evacuate the chamber, so as to reduce the environmental pressure of the molten steel and promote the removal of gas elements such as N and H in the molten steel; ② Using a supersonic oxygen gun, the molten steel is top-blown with O in a vacuum chamber. 2 Carry out vacuum oxygen decarburization, under the action of selective oxidation principle, protect alloy elements and promote decarburization reaction in depth; ③ sto...

AI Technical Summary

Problems solved by technology

[0003] VOD vacuum refining can achieve a large amount of decarburization of molten steel, and can effectively remove impurity elements such as O, N, and H in molten steel, but the traditional VOD smelting process has the following problems: ① During the VOD vacuum refining process, a large amount of Ar is consumed ②Oxygen is used as an oxidant, so that the oxygen content of molten steel is relatively high in the middle of the VOD treatment. After the oxygen blowing is stopped, a long period of vacuum carbon deoxidation treatment is required, and the smelting cycle is correspondingly extended, and the smelting efficiency is low.

In order to obtain relatively pure gas, various methods often cause problems such as a decrease in gas separation efficiency and an increase in production costs.

Images