Chemical cleaning and sewage treatment process of reverse osmosis membrane

Abstract

The invention discloses a chemical cleaning and sewage treatment process of a reverse osmosis membrane, and relates to the field of sewage treatment, the cleaning step comprises membrane element detection, acid pickling, surfactant washing, clean water washing and detection after washing; the sewage treatment comprises the following steps: air floatation, flocculation chelation sedimentation, hydrolytic acidification, AO biochemical treatment and Fenton reaction, the coagulant comprises one or more of polyaluminum chloride, polyaluminum sulfate, polyferric sulfate and polyferric chloride, the chelating agent comprises one or more of EDTA-2Na, alpha-glucoheptonate sodium and EDTA-4Na, and the pH value of the coagulant is 7-8. The component of the flocculating agent is polyacrylamide; the chemical cleaning and sewage treatment process of the reverse osmosis membrane can effectively remove heavy metals in the sewage, prevents nitrate radicals and heavy metal ions in the sewage after the reverse osmosis membrane is cleaned from polluting the environment, is high in treatment efficiency and good in treatment effect, and can effectively treat the cleaning sewage.

Description

technical field [0001] The invention relates to the field of sewage treatment, in particular to a process for chemical cleaning of reverse osmosis membranes and sewage treatment. Background technique [0002] During the operation of the reverse osmosis system, heavy metal ions, microorganisms, insoluble particles, organic pollutants, bacterial microorganisms and other substances in the water contact with the membrane for a long time, and they will accumulate on the surface of the membrane, which will significantly reduce the flux and separation performance of the membrane. Therefore, it is necessary to replace the fouling membrane. The disassembled fouling membrane can remove inorganic, organic dirt, and microbial adsorption layers through physical and chemical methods such as dissolution, sterilization, and descaling to obtain a new reverse osmosis membrane. The current chemical The cleaning process can only remove fouling substances such as microorganisms, organic matter, ...

AI Technical Summary

Problems solved by technology

[0002] During the operation of the reverse osmosis system, heavy metal ions, microorganisms, insoluble particles, organic pollutants, bacterial microorganisms and other substances in the water contact with the membrane for a long time, and they will accumulate on the surface of the membrane, which will significantly reduce the flux and separation performance of the membrane. Therefore, it is necessary to replace the fouling membrane. The disassembled fouling membrane can remove inorganic, organic dirt, and microbial adsorption layers through physical and chemical methods such as dissolution, sterilization, and descaling to obtain a new reverse osmosis membrane. The current chemical The cleaning process can only remove fouling such as microorganisms, organic matter, and inorganic salt scaling, but it is difficult to form an effective desorption capacity for heavy metals

[0003] After the existing chemical cleaning process is completed, because nitric acid is used to assist in the removal of heavy metals, the cleaned sewage contains nitrate and heavy metal ions, which will bring great difficulty to the subsequent harmless treatment of sewage. , so it is necessary to use sewage treatment process to facilitate subsequent sewage purification and discharge

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