Recovery and comprehensive-utilization process for waste heat in dry-process treatment of iron-making slag in blast furnace

Abstract

The invention provides a recovery and comprehensive-utilization process for waste heat in dry-process treatment of iron-making slag in a blast furnace. The recovery and comprehensive-utilization process comprises the following steps: (S1) the blast-furnace slag enters a buffering tank through a slag drying trough, the heat of the slag is recovered by hot air in the buffering tank, and then the temperature of the slag is reduced; (S2) flue gas carrying the heat of the slag enters a waste-heat boiler through a pipeline, water steam is heated by heat exchange in the waste-heat boiler, and enters power generation equipment to be converted into electric energy; (S3) after heat exchange, the flue gas enters a dust remover for dust removal, and after dust removal, the flue gas enters a blow-off tower for exhaustion by a fan; and (S4) after temperature reduction, the slag enters a brick casting chain belt for casting and molding, and then enters a cold bed for package and storage. The recovery and comprehensive-utilization process provided by the invention has the advantages of safety, reliability, stability and benefit, and can create economic benefit while realizing recovery of the waste heat of the slag.

Description

technical field [0001] The invention relates to a steelmaking process, in particular to a comprehensive utilization process for waste heat recovery of blast furnace ironmaking slag dry process slag treatment. Background technique [0002] Composition of slag: blast furnace slag is mainly composed of acidic oxide SiO 2 、Al 2 o 3 and basic oxides CaO, MgO 4 composition. In the case of using ordinary iron ore to smelt steelmaking pig iron, the sum of these four components is more than 95%, and there are also a small amount of FeO, MnO and sulfides (CaS, MnS, etc.). When smelting special ores, the slag also contains other components. For example, when smelting Panzhihua vanadium-titanium magnetite, the slag contains 20% to 30% TiO 2 (see blast furnace smelting of vanadium-titanium magnetite); when smelting fluorine-containing ores, the slag contains about 18% CaF (see blast furnace smelting of Baiyan Obo Mine); when smelting ferromanganese, the slag contains relatively hig...

AI Technical Summary

Problems solved by technology

[0004] The existing water-quenched slag process, a large amount of heat energy in the slag is forced to be converted into water vapor to be released, the process occupies a large area, the resource loss is serious, and the comprehensive utilization is limited; the liquid slag contains heat energy and turns into steam (low-pressure waste heat), A lot of heat energy is wasted; the slag is flushed with water, changing the original slag to become a quenched slag, and carrying a large amount of water 10-20% to be transported to downstream users

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