Comprehensive utilization method of zinc-containing dust mud of steel plant

Abstract

The invention relates to a comprehensive utilization method of zinc-containing dust mud of a steel plant. The method comprises the following steps that the zinc-containing dust mud and diluted hydrochloric acid are ground and leached at the same time and then stirred and leached, and solid-liquid separation is carried out to obtain leach residues and a solution; lime milk is added into the solution, the ph value is controlled to be 6-9, and solid-liquid separation is carried out to obtain zinc hydroxide and a solution; lime milk is added into the solution, the ph value is controlled to be 9-10, and solid-liquid separation is carried out to obtain magnesium hydroxide and a solution; sulfuric acid is added into the solution, after stirring is carried out, solid-liquid separation is carried out to obtain calcium sulfate and diluted hydrochloric acid, and the hydrochloric acid is leached again; magnetic separation and flotation combined treatment is carried out on leach residues to obtainiron powder, carbon powder and tailings; and zinc hydroxide is subjected to leaching with an ammonium chloride solution, impurity removal purification and zinc electrodeposition, ammonia water is added, the ph value is kept within the range of 3-8, and zinc skin is melted and cast into a zinc ingot. According to the method, iron, carbon, zinc, calcium, magnesium and silicon in the zinc-containingdust mud are separated, extracted and enriched through the process combination of hydrochloric acid leaching, beneficiation iron and carbon separation, ammonia process zinc electrodeposition and the like, and the problems of environmental protection, efficiency, operation cost and the like of treatment of the zinc-containing dust mud of the steel plant are solved.

Description

technical field [0001] The invention relates to the technical field of comprehensive utilization of metallurgical waste, in particular to a method for comprehensive utilization of zinc-containing dust and mud in iron and steel plants. Background technique [0002] A large amount of dust sludge containing zinc will be produced in the production process of iron-making iron-making blast furnace and steel-making converter. Generally, the iron-carbon resources in the dust sludge with low zinc content can be used as secondary raw materials and returned to sintering or pelletizing. However, with the enlargement of blast furnace , the control of zinc is becoming more and more demanding, because zinc will form furnace nodules in the blast furnace, and nodules in the furnace will cause gas flow disorder in the upper part of the blast furnace, suspension and collapse of materials, condensation in the blast furnace gas pipeline and blockage, etc. question. At present, with the implemen...

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Problems solved by technology

[0007] The invention provides a method for comprehensive utilization of zinc-containing dust and sludge in iron and steel plants. Through hydrochloric acid wet separation of various elements-ore dressing enrichment of iron carbon-chlorine ammonia electrolytic deposition of metal zinc and other process combinations, the iron in zinc-containing dust and sludge , carbon, zinc, calcium, magnesium, and silicon are separated, extracted and enriched separately, which solves the problems of environmental protection, efficiency, investment cost, and operating cost of the existing zinc-containing dust sludge treatment process in iron and steel plants

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