Aluminum electrolysis flue gas purification method and dust collector

Abstract

The invention discloses an aluminum electrolysis fume purification method and a dust remover. According to the method, adsorbents of fresh aluminum oxide and fluorine-containing aluminum oxide are added into a purification system by means of main flue inlets and auxiliary flue inlets independently formed in all dust remover units; most electrolysis fume containing high-concentration hazard substances is subjected to primary purification after a large amount of fluorine-containing aluminum oxide is added into the system from the main flue inlets, and the fume subjected to primary purification is further purified through the fresh aluminum oxide added from the auxiliary flue inlets, so that fractional purification of the electrolysis fume is achieved. The method and the dust remover have the advantages that the purification effect is good, and the working efficiency of the dust remover is high. When two dust removers are arranged in a mirror mode, wall plates of boxes in the dust remover units can be used as main gas outlet pipes, and the system manufacturing cost can be lowered.

Description

technical field [0001] The invention relates to a purification method for purifying flue gas containing fluorine produced in the production process of electrolytic aluminum and a dust collector thereof, belonging to the technical field of electrolytic flue gas purification in the aluminum electrolysis industry. Background technique [0002] In the production of electrolytic aluminum industry, the electrolytic cell will produce a large amount of flue gas containing HF during the aluminum electrolysis process. If the HF in the flue gas enters the surrounding environment, it will cause environmental pollution and produce toxic and side effects on animals and plants. In the prior art, flue gas dry purification measures are usually adopted, that is, aluminum oxide is used to absorb hydrogen fluoride in the flue gas to purify harmful substances in the flue gas, and to control the emission of fluoride, so as to meet the national environmental protection emission standards and reduce...

AI Technical Summary

Problems solved by technology

However, in the traditional technology, fresh alumina and fluorine-containing alumina are added to the inlet pipe of the dust collector at the same time, and most of the fresh alumina with strong activity and large particles is separated by the inertial pre-separation device in the dust collector and falls into the ash hopper. It is sent back to the fluorine-containing alumina warehouse for electrolytic production, and part of it is repeatedly added to the purification system as circulating alumina

In the traditional technology, fresh alumina with strong activity has a short time to participate in flue gas purification, and most of it is separated and sent directly to the fluorine-containing alumina bin for electrolytic production. The activity of fresh alumina has not been fully utilized; in addition, it can With the flue gas flow, it adheres to the surface of the filter bag of the dust collector to form a "powder cake layer" to achieve the final filtration. The alumina is fluorine-containing alumina with poor adsorption activity and small particles, and the "powder cake layer" has poor adsorption activity.

The above problems affect the purification efficiency of alumina to hydrogen fluoride, resulting in unsatisfactory purification effect of traditional purification methods

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