Linear feeding method for aluminum electrolysis flue gas purification system

Abstract

The invention relates to an alumina batch charging technique of aluminum electrolysis, in particular to a linear feeding method of an aluminum electrolysis fume purification system. The method of the invention comprises the following steps: 1) batch charging procedure; 2) boiling procedure and 3) batch charging adjustment procedures; the technical conditions are that: the wind pressure of compressed air led into an air chamber at the bottom of a material chamber is 300Pa to 500Pa; the gradient between a boiling bed and a discharge port is 5 degrees to 10 degrees; the adjusting distance of an adjusting plate is 10mm; and the negative pressure of an underground flue is not lower than 400Pa. The technique solves the problem that a fume purification batch charging device of the purification system relies on foreign imported equipment, improves the purifying efficiency of the aluminum electrolysis fume purification system, with the perfluoro purifying efficiency higher than 99 percent; reduces the discharge of pollutants and eliminates environmental pollution caused by the failure of a reactor in the prior art. The liner feeding method of the invention can be widely applied to the fumepurification systems in the aluminum electrolysis production industry.

Description

technical field [0001] The invention relates to a feeding technology for aluminum electrolysis alumina, in particular to a linear feeding method for an aluminum electrolysis flue gas purification system. Background technique [0002] In the past, in the purification process of flue gas from aluminum electrolysis, VIR and Venturi reactors were used to carry out adsorption reaction to recover fluoride, but the effect was poor, and the feeding of the purification system was uneven, so that the fresh alumina could not fully react with the flue gas containing fluorine. The direct failure of the VIR and Venturi reactors caused the purification efficiency of the purification system to be low, the amount of alumina damage was large, and the fluidity of alumina powder was poor, which affected the purification efficiency of the purification system and the recovery and reuse of HF gas, which eventually led to The cost of using fluoride salts in aluminum electrolytic production increase...

AI Technical Summary

Problems solved by technology

[0002] In the past, in the purification process of flue gas from aluminum electrolysis, VIR and Venturi reactors were used to carry out adsorption reaction to recover fluoride, but the effect was poor, and the feeding of the purification system was uneven, so that the fresh alumina could not fully react with the flue gas containing fluorine. The direct failure of the VIR and Venturi reactors caused the purification efficiency of the purification system to be low, the amount of alumina damage was large, and the fluidity of alumina powder was poor, which affected the purification efficiency of the purification system and the recovery and reuse of HF gas, which eventually led to The cost of using fluorine salt in aluminum electrolysis production increases

At the same time, the original reactor was imported from the American PEC company, and its fluidization components were imported parts, which are no longer produced abroad, and it is difficult to purchase spare parts

Because the Venturi reactor and other put into use are poor, which affects the uniform feeding of the purification system, resulting in insufficient reaction between fresh alumina and fluorine-carrying flue gas, and even Venturi reactor failure, the purification efficiency of the purification system is low, and the alumina The amount of damage of the aluminum oxide powder is large, resulting in poor fluidity of the alumina powder, which in turn affects the purification efficiency of the purification system and the recovery of HF gas, resulting in poor purification efficiency of the electrolytic flue gas and increased production costs of aluminum fluoride

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