Arsenic-containing soot dearsenication method

Abstract

The invention discloses a dearsenication method of arsenic-containing soot in a pyrogenic smelting process of lead, copper, tin or the like. The method comprises the following steps: calculating the amounts of concentrated sulfuric acid and coal powder required by each ton of soot according to the arsenic content according to the following components in percentage by weight: 1% of As, 0.10-1.50% of concentrated sulfuric acid and 0.10-0.50% of coal powder; and evenly mixing the soot, concentrated sulfuric acid and coal powder; reduction roasting: adding the prepared raw materials into an electrothermal converter, starting a dust collection blower, heating to 300-450 DEG C, carrying out rotary roasting for 1.5-3 hours, and discharging; and leaching the dearsenicated roasted product in an indium recovery system to leach zinc and indium, and extracting to recover the indium. The reduction roasting is adopted to directly convert the arsenic into the finished product arsenic white, thereby avoiding the problem of stacking of the arsenic-containing slag and eliminating the hidden danger of environmental protection caused by stacking of the arsenic-containing slag. By adopting the sulfating roasting, the indium can be conveniently recovered, the leaching rate of the acidified soot is enhanced, and the recovery rate of indium can reach 95% above.

Description

technical field [0001] The invention relates to a method for removing arsenic from soot produced by pyrometallurgy, in particular to a method for removing arsenic from soot containing arsenic such as lead, copper and tin by pyrometallurgy. Background technique [0002] The by-product soot produced during pyrometallurgy of lead, copper, tin, and antimony usually contains elements such as arsenic and indium. The content of arsenic is 1-40%, and the content of indium can reach 5-8kg / t. Indium is a kind of scattered metal. How to comprehensively and efficiently separate the arsenic in the soot, and then recover indium, the traditional method is acid leaching or alkali leaching arsenic, and then converting the arsenic in the solution into scorodite (iron arsenate), and the leaching residue is passed through Indium is recovered by acid leaching and extraction; the second is treated by fire methods such as oxidation roasting, reduction roasting and vacuum roasting, and the...

AI Technical Summary

Problems solved by technology

Acid leaching or alkali leaching is used to remove arsenic, and arsenic forms iron arsenate, which needs to be stored in a special site, and there are long-term environmental safety hazards; the second method is the conversion of arsenic into products, but a large amount of indium also volatilizes, and the loss of indium is serious.

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