A method for reducing the toxicity of heavy metal solid waste leaching

Abstract

The invention discloses a method for eliminating the leaching toxicity of heavy metal solid waste residues. The method comprises the steps that after the heavy metal solid waste residues are subjected to iron removal by magnetic separation, a leaching activating agent and a reducing reinforcing agent are uniformly mixed, a leaching agent is added, leaching is carried out for 1-3 hours in a metal tank at normal temperature, a flocculating agent of polyacrylamide is added into a leaching solution, a metal plate type or mesh type electrode and the metal groove are adopted as electrodes, and electric-assisted leaching is carried out for 1-5 hours; and after leaching is completed, the leaching solution is subjected to liquid-solid separation, valuable metals are recycled from filter liquor, filter residues are washed with hot water and then are piled up. According to the method for eliminating the leaching toxicity of the heavy metal solid waste residues, the valuable metals such as vanadium, copper, cobalt, nickel, zinc and manganese can be recovered at the same time, and the problem of harm-reducing and recycling comprehensive utilization of the heavy metal solid waste residues can be solved; the method is suitable for disinfecting and detoxifying wet-process solid waste residues of nonferrous metals such as the vanadium, the cobalt, the copper, the zinc, chromium and the nickel and ferrous metals such as the manganese and the chromium, and no new pollution can be generated in the process; and the method is simple in process, low in cost and convenient for large-scale industrial implementation.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, and relates to a method for reducing the leaching toxicity of heavy metal solid waste residue, especially in the process of extracting and comprehensively utilizing non-ferrous metals such as zinc, nickel, cobalt, copper, vanadium, and ferrous metals such as manganese and chromium. A method for disinfection and harm reduction of metallurgical acidic solid waste and neutral solid waste with high heavy metal residues and heavy metal leaching toxicity. Background technique [0002] The dissolution of heavy metal ions is the main cause of environmental hazards caused by solid waste residues. All kinds of hydrometallurgical solid waste residues are exposed to rainwater, especially acid rain, and the heavy metals contained in them will dissolve and migrate, directly causing persistent pollution of the soil environment and water environment, damaging the ecological environment, and seri...

AI Technical Summary

Problems solved by technology

This method is a conventional leaching method with the addition of leaching aids. It is aimed at the comprehensive recovery of toxic elements including but not limited to heavy metals in solid waste residues. There is no method for reducing leaching toxicity for major environmentally sensitive heavy metal elements.