Method for smelting high-concentration sulfur dioxide by utilizing zinc oxide dust to absorb lead and zinc

Abstract

The invention provides a method for absorbing lead-zinc smelting high-concentration sulfur dioxide through zinc oxide smoke dust. The method includes the steps that water is added into zinc oxide smoke dust obtained after dust collection, and slurry is prepared; an absorption tower of a tower-tank split structure is established, a bottom tank for storing the cyclic zinc oxide slurry is arranged on the lower portion of the tower, a sulfur dioxide smoke inlet is formed in the lower portion of the absorption tower, a spraying layer is distributed on the upper portion of the absorption tower, and the spraying layer is composed of a sprayer and a pipeline; the zinc oxide slurry is introduced into the sprayer through the pipeline to be sprayed, and encounters and reacts with sulfur dioxide gas ascending reversely to generate zinc sulfate or zinc hydrosulfite, zinc sulfate or zinc hydrosulfite is gathered on the lower portion of the absorption tower, and desulfurized gas is exhausted from the upper portion; the zinc oxide slurry which does not completely react in the bottom tank is delivered back to the sprayer through a circulating pump to be atomized and sprayed, and the zinc oxide slurry continues to react with sulfur dioxide; zinc sulfate liquid and zinc hydrosulfite solids generated through the reaction in the bottom tank on the lower portion of the absorption tower are delivered to a leaching workshop for next-step treatment; zinc hydrosulfite in the cyclic slurry is separated through a cyclone. Byproducts can be comprehensively utilized, small space is occupied, equipment is not blocked, production is smooth, the removal rate of sulfur dioxide is high, ultra-low emissions of sulfur dioxide are achieved, waste is used for treating waste, cost is low, and efficiency is high.

Description

technical field [0001] The invention relates to a technology for resource management of industrial harmful gases, in particular to a method for smelting high-concentration sulfur dioxide by absorbing lead and zinc with zinc oxide dust. Background technique [0002] The control of lead-zinc smelting flue gas is an environmental protection problem that non-ferrous metal smelting enterprises have been seeking to solve. As the national environmental protection requirements become more and more stringent, enterprises that do not comply with the national environmental protection policy will be shut down, converted or eliminated soon. The working conditions of the rotary kiln production process in the lead-zinc smelting industry fluctuate greatly, and the concentration of sulfur dioxide in the flue gas of the rotary kiln is 13000mg / Nm 3 -21000mg / Nm 3 (The concentration of sulfur dioxide in this kind of flue gas is less than the requirements for acid production, and the flue gas is...

AI Technical Summary

Problems solved by technology

[0005] However, wet desulfurization has the following disadvantages: the sulfur dioxide produced in the flue gas of the rotary kiln has a large gas volume, and a large amount of absorbent needs to be purchased, the transportation distance of the absorbent is long, the economic benefit is poor, and the operating cost of flue gas desulfurization is high

In addition, wet desulfurization absorption equipment and pipelines are prone to corrosion, fouling, and blockage. If the limestone method is used for flue gas treatment, the process control is improper, and the inner wall of the absorption tower, nozzles, and demisters are prone to fouling, and the absorption of flue gas will produce a large amount of secondary Calcium sulfate is stored in the waste slag yard, and the by-products cannot be comprehensively utilized

[0006] If it is not effective to use such a wet method to treat a large amount of high-concentration sulfur dioxide gas produced in lead-zinc smelting, it is necessary to develop new treatment technologies

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