LIN Jin-tang,HAN Yong-hui,XU Ze-bin,et al.Performance of Different Ultrafiltration Combined Processes for Treatment of Filter Backwash Wastewater[J].China Water & Wastewater,2021,37(15 15):28-34.
Performance of Different Ultrafiltration Combined Processes for Treatment of Filter Backwash Wastewater
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
15 15
Page:
28-34
Column:
Date of publication:
2021-08-01
- Abstract:
- In order to investigate the treatment effect of ultrafiltration on filter backwash wastewater and the control effect of combined processes on membrane fouling, three different processes (direct ultrafiltration, on-line coagulation/ultrafiltration and coagulation/sedimentation/ultrafiltration) were employed to treat filter backwash wastewater. Turbidity removal efficiencies of the three processes were all above 99.5%, and the effluent CODMn concentrations were always below 1.20 mg/L, indicating that ultrafiltration had excellent turbidity and CODMn removal performance. UV254 removal efficiency of direct ultrafiltration was (26.93±4.14)%, while the UV254 removal efficiencies of on-line coagulation/ultrafiltration and coagulation/sedimentation/ultrafiltration reached (37.41±3.57)% and (40.87±6.22)%, respectively, which were obviously better than that of direct ultrafiltration. The three treatment processes had no obvious removal effect on fluorescent pollutants in raw water. Effluent quality of the three processes, membrane fouling, FTIR spectroscopy and membrane surface morphology were analyzed. It was found that the membrane fouling caused by direct ultrafiltration was the most serious, and irreversible fouling played a dominant role. The effluent quality indicated that pretreatment could reduce the pollutant load in the influent of the ultrafiltration and change the form of pollutants in the water. Therefore, pre-coagulation could effectively relieve membrane fouling and the coagulation/sedimentation/ultrafiltration process had the best alleviating effect on membrane fouling. Meanwhile, membrane fouling model fitting results showed that the main membrane fouling mechanism of direct ultrafiltration was cake filtration and intermediate blocking.
Last Update:
2021-08-01