Method for utilizing ion exchange wastewater in wastewater treatment process in phosphorus chemical industry

Abstract

The invention relates to a method for utilizing ion exchange wastewater in a wastewater treatment process in phosphorus chemical industry, which comprises the following steps: collecting regenerated wastewater of an ion exchanger into a collecting tank; carrying out primary neutralization and primary settlement on acidic wastewater containing fluorine and phosphorus, extracting ion exchange wastewater from the collecting tank to substitute back titration acid according to fluorine, phosphorus and pH value of the slurry, and adding the ion exchange wastewater to the wastewater which is being treated to regulate the acidity until the consumption of alkaline solution by fluorine and phosphorus in the wastewater is basically equivalent to that of hydrogen ions, so that the pH value of the treated wastewater in phosphorus chemical industry is increased, thereby being beneficial to secondary treatment of wastewater; carrying out secondary neutralization and secondary settlement, and adding the ion exchange wastewater again, so that the acidity of the wastewater is further lowered, and the flocculation effect of the secondary settlement is good; and sending the treated wastewater, which meets the emission standard, into a clean water tank. The method provided by the invention recycles the ion exchange wastewater, lowers the amount of effluent wastewater, reduces the consumption of the back titration acid, and ensures the pH value of the effluent water to be qualified.

Description

technical field [0001] The invention relates to wastewater treatment, in particular to the treatment and recycling of anion-cation exchange wastewater. Background technique [0002] As we all know, the acid wastewater discharged by the phosphorus chemical industry needs to be neutralized with an alkaline solution such as lime emulsion to reduce the acidity to the allowable discharge standard before it can be discharged. According to investigations and studies, the amount of calcium salt consumed by fluorine and phosphorus in acidic wastewater is greater than the amount of salt consumed by hydrogen ions, which will inevitably increase the amount of alkaline solution; adding a large amount of excessive calcium salt will cause the pH value of the slurry in the secondary sedimentation system to be too high. The flocculation effect of the sedimentation system is poor. Although a lot of calcium salts are consumed, the fluorine and pH values ​​in the wastewater cannot meet the disc...

AI Technical Summary

Problems solved by technology

[0006] Since the existing acidic wastewater treatment process of the phosphorus chemical industry is a process of neutralizing by adding alkaline solution twice, and then performing sedimentation treatment, the pH value of the slurry is too high every time in neutralization, and the flocculation effect of the sedimentation system is poor. Therefore, the method for recycling ion exchange wastewater provided by the inventor is first to collect the regeneration wastewater of the ion exchanger through the collection pool; after the acid wastewater containing fluorine and phosphorus undergoes primary neutralization and primary sedimentation, According to the fluorine, phosphorus and pH value in the slurry, the ion exchange wastewater is extracted from the collection tank to replace the back-dripping acid, and added to the wastewater being treated for acidity adjustment, so that the consumption of fluorine and phosphorus in the wastewater to the alkaline solution and the consumption of hydrogen ions In this way, the pH value of the treated industrial wastewater is increased, which is beneficial to the secondary treatment of wastewater; after secondary neutralization and secondary sedimentation, ion exchange wastewater is added again to further reduce the acidity of phosphorus chemical wastewater. The flocculation effect of the secondary sedimentation is good; after the treatment, the wastewater meets the discharge standard and is sent to the clean water tank

Images