A cleaning method for high-arsenic, fluorine- and chlorine-containing materials

Abstract

A method for cleaning high-arsenic, fluorine- and chlorine-containing materials, comprising: (1) performing reduction smelting after mixing high-arsenic, fluorine-and-chlorine materials, a reducing agent and a flux to obtain sulfur matte, lead alloy, smelting flue gas and slag; (2) Mix the flue gas from high-temperature smelting with air and oxidize it. The obtained mixed flue gas is cooled and then electrostatically collected to obtain primary solid soot and primary arsenic-containing flue gas; (3) Pass the primary arsenic-containing flue gas through the metal film Filtration to obtain secondary solid soot and secondary arsenic-containing flue gas; (4) Quenching the secondary arsenic-containing flue gas to collect arsenic to obtain arsenic trioxide solid and flue gas of fluorine and chlorine. Arsenic sulfide slag and waste liquid are obtained; the waste liquid is evaporated and crystallized to obtain a mixed solid containing sodium chloride and sodium fluoride. The invention realizes the clean emission of flue gas in the smelting process of high-arsenic, fluorine-containing and chlorine-containing materials without secondary pollution, and has the advantages of high efficiency, environmental protection, safety and the like.

Description

technical field [0001] The invention belongs to the technical field of comprehensive recovery of nonferrous metals, and in particular relates to a cleaning treatment method for high-arsenic, fluorine- and chlorine-containing materials. Background technique [0002] In the deposits of non-ferrous metals such as copper, lead and zinc, arsenic is the main associated element. During the smelting process, arsenic will be enriched with the smelting metal (the amount of arsenic produced by copper smelters is 32500t / a, and that of lead smelters is 16100t / a a, the zinc smelter is 22400t / a), forming high-arsenic polymetallic materials (when the mass percentage of arsenic in the material is ≥ 2%, the material is called high-arsenic material). During the smelting process, arsenic, fluorine, and chlorine will enter into the smelting soot. For example, zinc oxide soot from fuming furnaces for lead smelting and zinc oxide soot from multi-hearth furnaces for zinc smelting contain high leve...

AI Technical Summary

Problems solved by technology

[0004] (1) It is difficult to completely capture arsenic-containing smoke and dust, and it is easy to produce secondary pollution

There is no corresponding equipment and facilities to capture arsenic, and the arsenic compound is directly volatilized into the flue gas, causing air pollution

The arsenic-containing flue gas obtained through reduction smelting has the characteristics of large flue gas volume, high temperature, high dust content, and fine dust particle size. The conventional dust collection method is to use a bag filter, and the filter bag used for bag dust collection is ordinary. material, it is easy to stick to the filter bag, resulting in low dust collection efficiency and low arsenic collection purity

[0005] (2) The purity of the obtained arsenic product is not high

Most of the treatment of arsenic in the current technology is mainly for the treatment of arsenic-containing fume, and in the process of processing this kind of soot, it is often considered that the arsenic in the soot exists in the form of arsenic trioxide, ignoring other arsenic-containing phases, so As a result, the purity of the final arsenic product is not high

[0006] (3) Only consider certain harmful substances in materials and ignore other harmful elements

Resulting in exhausted flue gas that is not completely clean

[0007] (4) Harmful substances generated by the reaction between arsenic and fluorine and chlorine are not considered

This process ignores the typical characteristics of high-fluorine and chlorine zinc oxide soot raw materials: high arsenic content, only the fluorine and chlorine in it are cleaned and disposed, and the arsenic in the raw material is not disposed of accordingly, which poses a potential threat to the environment

Moreover, although fluorine and chlorine are removed, they exist in the waste liquid. Since the waste liquid is polluted acid and has complex components, it is difficult to recycle fluorine and chlorine, which still poses a potential threat to the environment.

Images