Method for harmless and recycling treatment of stainless steel acid washing waste water neutralization sludge

Abstract

The invention discloses a method for harmless and recycling treatment of stainless steel acid washing waste water neutralization sludge, belonging to the field of harmful and valuable heavy metal resource recovery. The stainless steel acid washing waste water neutralization sludge is leached out by sulphuric acid, harmful and poisonous metals manganese, nickel and chromium enter into the leachate, and harmless treatment is carried out on the sludge. Separation, enrichment and recovery of metal resources of iron, manganese, chromium and nickel in the leachate are realized by adopting goethite method, potassium permanganate oxidation method, anion resin exchange method and chelate resin absorption method respectively, and effluent up to the standard is discharged after treatment or is returned to water consuming link in technologic process. The method of the invention has short technological flow, simple operation, management convenience, high recovery rate of valuable metal resources of manganese, nickel and chromium, recycling of multiple valuable metals is realized while the sludge is subject to harmless treatment, and unification of economic benefit, environmental benefit and social benefit is realized.

Description

technical field

[0001] The present invention relates to the harmless and resourceful disposal method of the neutralized sludge in stainless steel production, electroplating industry and related surface treatment industrial wastewater, in particular to the harmless disposal and recycling of the neutralized sludge in the toxic waste water of the stainless steel pickling industry. A method for resource recovery of valuable metals. Background technique

[0002] During the surface pickling process of stainless steel, a large amount of acid wastewater containing heavy metal ions such as nickel, chromium, and manganese is produced. At present, most stainless steel pickling enterprises still use the traditional neutralization precipitation method to remove heavy metals, resulting in a large amount of toxic sludge containing various heavy metals. The heavy metals in this kind of sludge mostly exist in the state of hydroxide, oxide, carbonate, etc., which are very unstable and easy t...