XIEYa-wei,CHENWei-jie,YUWen-qing,et al.Effect of Chemical Cleaning on Aging of Structure and Performance of PVDF Ultrafiltration Membrane in a Water Treatment Plant[J].China Water & Wastewater,2025,41(11):1-8.
Effect of Chemical Cleaning on Aging of Structure and Performance of PVDF Ultrafiltration Membrane in a Water Treatment Plant
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第11期
Page:
1-8
Column:
Date of publication:
2025-06-01
- Keywords:
- （1. College of Civil Engineering; Zhejiang University of Technology; Hangzhou 310023; China; 2. Zhejiang Supcon Information Co. Ltd.; Hangzhou 310056; China; 3. Water Treatment Branch; Ningbo Water Environment Group Co. Ltd.; Ningbo 315000; China）
- Abstract:
- In order to solve the aging problem of the structure and performance of ultrafiltration membranes by chemicals in a water treatment plant in Zhejiang Province during long-term chemical cleaning, the aging tests of three commonly used cleaning solutions (2 000 mg/L citric acid, 1 000 mg/L NaClO, and 1 000 mg/L NaClO + 250 mg/L NaOH ) were carried out to analyze their effects on two polyvinylidene fluoride (PVDF) ultrafiltration membranes (1# and 2#) in the water treatment plant. The results showed that the cleaning of three solutions would lead to the decomposition of polyvinyl pyrrolidone (PVP), the surface modification additive of the two membranes, thereby destroying the surface structure of the ultrafiltration membrane and reducing the hydrophilicity, and the degree of influence was NaClO>NaClO+NaOH>citric acid. Chemical cleaning led to the reduction of the mechanical properties of the ultrafiltration membrane, which was related to the decomposition of additives on the surface of the membrane. The aging effect of the PVDF main supporting layer of the ultrafiltration membrane was not significant, the overall mechanical properties decreased slightly, and the characteristic peaks of PVDF did not change much during the cleaning process, but the 1# membrane had a slight defluoride reaction in the late cleaning stage of NaClO+NaOH solution. In comprehensive comparison, the aging effect of NaClO solution cleaning on the two membranes was greater than that of NaClO and NaOH combined cleaning, while the aging effect of citric acid was the weakest. Considering the cleaning effect of different solutions on membrane fouling, long-term cleaning of NaClO solution should be avoided in the production of this water treatment plant, and it is recommended to use NaOH combined cleaning to slow down the aging of membrane to a certain extent.
Last Update:
2025-06-01