Comprehensive recycling method for high-arsenic soot

Abstract

The invention discloses a comprehensive recycling method for high-arsenic soot. The method specifically comprises the following steps that two-stage leaching is conducted on the high-arsenic soot; two-stage leaching liquid enters a cyclone electrolytic system for extracting copper, and a copper product is obtained through two-stage deep decoppering; then arsenic removal is conducted, and copper-arsenic slag and a zinc sulfate solution are obtained; the copper-arsenic slag is subjected to alkaline leaching, oxidization-crystallization, prereduction and the cyclone electrolytic technology, and simple substance arsenic is produced; lead and silver in high-pressure leaching residuals are subjected to lead conversion through ammonium bicarbonate and ammonium hydroxide, the lead is made to enter feed liquid, and a lead-containing solution is obtained after solid-liquid separation to recycle the lead; and the leaching residuals are leached through thiourea, a silver-containing solution is obtained, and silver powder is obtained through replacement. According to the comprehensive recycling method, various valuable metals in the high-arsenic soot are recycled through different techniques; and meanwhile, the techniques are combined organically, basically no waste slag or waste water or waste gas or other matter is generated from the whole system, the recycling degree is high, the techniques are advanced, the recycling rate is high, the recycling cost is low, and the comprehensive recycling method has quite remarkable environment protection significance.

Description

technical field [0001] The invention belongs to the technical field of nonferrous metal hydrometallurgy, and in particular relates to a method for comprehensive recovery and treatment of high-arsenic soot, that is, a method for comprehensively recovering valuable metals such as lead, copper, arsenic, zinc and silver from high-arsenic soot. Background technique [0002] At present, the treatment of high-arsenic soot at home and abroad mainly focuses on the treatment of arsenic removal, and the methods can be divided into the following types: [0003] (1) Roasting arsenic removal: Roasting arsenic removal is mainly a method of volatilizing arsenic in the form of arsenic trioxide at high temperature, thereby separating it from valuable metals. It is mainly divided into oxidation roasting, reduction roasting and vacuum roasting. After the arsenic-containing waste residue is crushed, it is oxidized and roasted at 600-850°C. The arsenic in the arsenic residue volatilizes under hig...

AI Technical Summary

Problems solved by technology

Alkaline leaching for arsenic removal is mainly a process in which arsenic-containing soot dissolves arsenic from the soot into the liquid phase under the action of an alkaline leaching agent. Commonly used alkaline leaching agents include sodium hydroxide, ammonia water, etc., and sometimes compound alkaline leaching agents such as NaOH -NaS NH 3 -NH 4 HCO 3 Compared with acid leaching, alkaline leaching has the advantages of mild leaching conditions and saving reagents. Compared with roasting arsenic removal, leaching has significantly improved working conditions, wide application range and low energy consumption. The advantages of low cost and rich technical means, in addition, according to the characteristics of raw materials, different schemes can be used to prepare different arsenic products, which realizes turning waste into treasure and prevents secondary pollution. The leaching dearsenic method is the main soot arsenic removal method , but the process is long, and leaching agent needs to be added, the cost is high, and the leaching agent introduced is unfavorable for the extraction of other valuable metals in high-arsenic soot

[0005] (3) Valuable metals are directly recovered: the arsenic is not treated, and the valuable metals in high-arsenic soot, such as copper, lead, and zinc, are directly recovered. Since these valuable metals exist in the form of sulfides, the traditional wet method It is difficult to effectively recycle the process, so the pyrotechnic process is generally used to treat the high-arsenic soot again, which not only has a low recovery rate of valuable metals, but also easily causes secondary pollution. Secondary pollution, while only part of the valuable metals are recovered, the recovery rate is low

[0006] In summary, no matter whether it is roasting arsenic removal method, leaching arsenic removal method or direct recovery of valuable metals, the systemic recovery of high-arsenic soot cannot be carried out. Not only the valuable metals in high-arsenic soot cannot be effectively recovered, Moreover, the problem of arsenic pollution is difficult to be completely solved

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