WANGRui,HUHui-zhi,SHAOSen-lin.Effect of Flux on Manganese Removal and Hydraulic Resistance in a Membrane?based Manganese Removal Process[J].China Water & Wastewater,2023,39(9):26-32.
Effect of Flux on Manganese Removal and Hydraulic Resistance in a Membrane?based Manganese Removal Process
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第9期
Page:
26-32
Column:
Date of publication:
2023-05-01
- Keywords:
- manganese removal; ultrafiltration; flux; membrane fouling; cake layer structure; decentralized water supply
- Abstract:
- In an ultrafiltration process, manganese oxides with catalytic activity are deposited on the membrane surface to form an activated cake layer, which has catalytic ability to remove manganese. However, the cake layer can cause severe membrane fouling. To better utilize the activated cake layer to enhance the Mn2+ removal, the effect of Mn2+ removal by activated cake layer and the resistance trends in ultrafiltration system were investigated at fluxes of 5 L/(m2· h), 10 L/(m2· h), 15 L/(m2· h) and 20 L/(m2· h). The results showed that at the flux of 5 L/(m2· h), the ultrafiltration system not only achieved high Mn2+ removal, but also had essentially no increase in hydraulic resistance. Contrarily, the hydraulic resistance of the activated cake layer increased rapidly at high fluxes. The analysis of the composition and morphology of the activated cake layer has revealed that under low flux conditions, the particle size of manganese oxides in the cake layer was larger, and the structure was sparser. This, in turn, contributed to maintaining a low hydraulic resistance. Moreover, due to the adsorption and oxidation by manganese oxide, it could form agglomerates by itself, so that the cake layer exhibited a heterogeneous structure. This structure could be effectively formed and maintained at low fluxes, and thus greatly slowing down the increase of hydraulic resistance.
Last Update:
2023-05-01