Chemical cleaning method of ultrafiltration membrane

Abstract

The invention discloses an ultrafiltration membrane chemical cleaning method and aims at an ultrafiltration membrane that is used for processing purified PTA waste water. The invention uses an acid lotion prepared by citric acid and sodium bisulfite for dissolving and eluting inorganic pollutants that are formed by cobalt and manganese ion hydroxide, deposited and absorbed on the surface of the ultrafiltration membrane, and uses an alkaline oxidative lotion that contains sodium hypochlorite for dissolving and eluting organic colloid pollutants that are deposited and absorbed on the surface ofthe ultrafiltration membrane. The ultrafiltration membrane chemical cleaning method can effectively elute the pollutants, recover the running flux and running pressure of the ultrafiltration membrane, and ensure stable running of the purified PTA waste water in an ultrafiltration process.

Description

A chemical cleaning method for ultrafiltration membrane technical field The invention relates to a chemical cleaning method for an ultrafiltration membrane, in particular to a chemical cleaning method for an ultrafiltration membrane for treating PTA refining wastewater. By adopting the method of the invention, the influence of ultrafiltration membrane fouling on the membrane treatment process can be effectively removed, and the stable progress of the PTA wastewater membrane treatment process can be ensured. Background technique In order to effectively treat the refined wastewater of purified terephthalic acid (PTA) and achieve the purpose of wastewater reuse, the inventor has adopted a treatment method based on a membrane method. The method is characterized by: removing the PTA in the wastewater by ultrafiltration Macromolecules and colloidal substances are removed by reverse osmosis filtration to remove organic matter and metal ions in wastewater, and then further remove ...

AI Technical Summary

Problems solved by technology

The composition of PTA refining wastewater is complex, which contains colloidal substances formed by organic substances such as cobalt, manganese ions and PTA. Before membrane treatment, by adjusting the pH and water temperature, most of the colloidal substances in the wastewater can be destabilized and precipitated to form suspensions. After the pre-filtration treatment before the membrane, most of the colloidal substances are removed in the form of suspended solids, but there are still some suspended solids and unseparated colloidal substances entering the ultrafiltration unit. As the ultrafiltration runs for a certain period of time, the ultrafiltration membrane fouling

Due to the unique pollutant composition and colloidal characteristics in PTA refining wastewater, the cleaning effect of the chemical cleaning formula and cleaning method in the prior art is not good, and cannot meet the cleaning requirements of the PTA refining wastewater membrane treatment process