Method for removing aluminum from anodizing chemical-polishing effluent and recycling system

Abstract

The invention provides a method for removing aluminum from anodizing chemical-polishing effluent. The method comprises the following steps: a, uniformly mixing aged chemical-polishing bath solution and rinsing water containing the chemical-polishing bath solution, so as to form a mixed solution; b, cooling the mixed solution to below 45 DEG C by a heat exchanger; c, filtering the cooled mixed solution by a bag filter and intercepting particles with the particle size being more than 5 mum; d, conveying the solution treated by the filter to an NF (nanofiltration) membrane separation system witha high pressure pump, so as to obtain high-concentration aluminum effluent and aluminum-removed purified acid solution; e, pumping the aluminum-removed purified acid solution into an evaporation system and evaporating and concentrating the aluminum-removed purified acid solution to the recyclable standard.

Description

technical field [0001] The invention relates to the technical field of waste liquid treatment and recovery, in particular to a method for removing aluminum from anodized waste liquid and a recovery system. Background technique [0002] Aluminum alloys are widely used in industry. Aluminum alloy products are often subjected to anodic oxidation treatment in order to enhance the surface decoration performance and corrosion resistance and other reliable performance. Typical aluminum alloy anodizing production processes include degreasing and cleaning, alkali etching, chemical polishing, ash removal, anodizing, dyeing and sealing, and multiple washings after each treatment process. Among them, chemical polishing refers to the use of chemical potions to dissolve the surface of the aluminum alloy and increase the smoothness and gloss of the surface. The commonly used chemical throwing tank liquid is a mixture of concentrated phosphoric acid, concentrated phosphoric acid and sulfu...

AI Technical Summary

Problems solved by technology

This results in the production of aluminium-rich phosphoric acid waste

In addition, when the product is transferred from the chemical throwing tank to the washing tank, a large amount of bath liquid is brought into it, resulting in a large amount of acid-containing aluminum-containing rinsing wastewater

[0003] For the treatment of these two types of waste liquids, the industry generally adopts the methods of adding alkali to neutralize and flocculating and settling. This method will consume a large amount of chemicals and generate a large amount of sludge, which is not only costly, but also causes waste of resources.

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