Heavy metal waste acid and wastewater resource recycling method and device

Abstract

The invention discloses a heavy metal waste acid and wastewater resource recycling method and device. According to the method, acids in waste acid can be well separated through selection of anionic and cationic membranes in the electrodialysis process, heavy metal ions still remain in a waste acid solution, and the separated acid enters a concentration basin, has the acidity of over 8 percent and can be used for a sulfuric acid preparation process; the acidity of the treated waste acid is reduced to a pH value of over 3, valuable heavy metals in heavy metal-containing low-acidity waste liquor can be rapidly recovered by utilizing a hydrogen sulfide and jet process integration technology, and the recovery rate of the heavy metal ions is over 95 percent; the residual low-acidity low-salt wastewater can be recycled for a spraying system. According to the method, the heavy metal waste acid and wastewater can be treated at high efficiency, the phenomena that neutralization residues which are difficultly treated are generated and secondary pollution is caused in the process of neutralizing by adopting alkalis are avoided, high-quality sulfuric acid and heavy metals can be recovered, and more important, the adopted equipment and device are simple, convenient to operate and good in treatment effect.

Description

technical field [0001] The invention belongs to the technical field of heavy metal polluted acid wastewater treatment, and in particular relates to a resource recycling method and device for heavy metal polluted acid wastewater. Background technique [0002] Domestic acid smelting flue gas mainly comes from the smelting process of copper, nickel, lead, zinc, gold and other metals. The smelting flue gas uses wet purification process in the process of sulfuric acid production. A large amount of acidic wastewater, namely dirty acid, will be produced in the process of tower, power wave and electrostatic demisting. Sewage acid wastewater is strongly acidic, the concentration of sulfuric acid in the sewage acid is between 2% and 11%, and it also contains copper, lead, mercury, antimony, zinc, arsenic, cadmium, indium, nickel, tin, manganese, fluorine, chlorine It is currently the main source of acidic heavy metal ion wastewater in smelters. Due to the high acidity and heavy meta...

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Problems solved by technology

[0027] Due to the high acidity of polluted acid, the conventional treatment adopts the neutralization treatment method. The simple neutralization method not only wastes sulfuric acid resources, but also produces a large amount of neutralization waste residue during the treatment process, which contains heavy metal ions. It belongs to hazardous waste. The heavy metals in the waste residue are of low grade and difficult to achieve recycling. It must be disposed of safely, otherwise it will easily cause secondary pollution

In the process of treating dirty acid by sulfuration method, secondary pollution of hydrogen sulfide is easy to be generated, and the sulfuration efficiency is low, and the recovery rate of heavy metals is low

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