Zero draining and recycling process of aluminum and aluminum alloy chemical polishing waste liquid

Abstract

The invention relates to a zero draining and recycling process of aluminum and aluminum alloy chemical polishing waste liquid. The process is characterized by comprising the following steps of firstly, chemical polishing, wherein a polishing workpiece is soaked into chemical polishing solutions in a chemical polishing groove to be polished; secondly, cooling buffering, wherein the polishing workpiece obtained after chemical polishing treatment is transferred to solutions in the cooling buffer groove to be cooled and buffered; thirdly, drip recycling, wherein the polishing workpiece obtained after cooling and buffering is transferred to a drip recycling groove to have drip treatment, and a recycling outlet in the bottom of the drip flow recycling groove recycles waste liquid on the surface of the polishing workpiece; fourthly, washing, wherein the polishing workpiece obtained after drip flow treatment enters a washing groove to have washing treatment. In a word, the process has the advantages of being recyclable, high in recycling rate, safe, and environmentally friendly, and reducing pollutions.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, in particular to a metal chemical polishing waste liquid zero discharge and recovery process, in particular to an aluminum and aluminum alloy chemical polishing waste liquid zero discharge and recovery process. Background technique [0002] Phosphoric acid, sulfuric acid and nitric acid (or special polishing liquid) are mostly used in the aluminum chemical polishing process. Since the polishing temperature is relatively high, generally between 90-120 degrees or even higher, the polished workpiece is transferred to water washing in the air. The time of the tank should not be too long, otherwise there will be adverse phenomena such as over-corrosion. In addition, since there will be many bubbles attached to the surface of the aluminum parts during polishing, it is not easy to drip back into the polishing tank, resulting in too much consumption, and the brought out tank liquid enter...

AI Technical Summary

Problems solved by technology

In addition, since there will be a lot of air bubbles attached to the surface of the aluminum parts during polishing, it is not easy to drip back to the polishing tank, resulting in too much consumption, and the brought out tank liquid enters the next washing tank to generate a large amount of waste liquid

[0003] At present, the solution to the transfer of workpieces in the air is mainly to add corrosion inhibitors or brighteners with corrosion-inhibiting effects in the polishing tank, which can prolong the transfer time in the air and reduce the loss of potions, but the consumption of the final surface is still relatively large and cannot completely solve the problem

The waste liquid entering the washing tank is usually flowed into the wastewater treatment tank for treatment, mainly by adding sodium hydroxide or lime for neutralization and precipitation, and then performing pressure filtration to form waste residues, which greatly increases the pressure and cost of wastewater treatment.

[0004] Some enterprises recycle and reuse the first water washing after polishing, but the excessively high aluminum ions in the recovered solution cannot be removed and the recovered solution cannot be used for normal production. These excessive aluminum ions mainly come from polishing in the tank and air transfer When the workpiece reacts with the polishing solution, the concentration of aluminum ions is higher than that in the polishing tank