WANGShao-zhu,LIXing,FENGJian-yong,et al.Filtration Performance and Bio-cake Layer Characteristics of Pre-coated Gravity-driven Membrane (GDM)-based Drinking Water Process[J].China Water & Wastewater,2024,40(13):21-27.
Filtration Performance and Bio-cake Layer Characteristics of Pre-coated Gravity-driven Membrane (GDM)-based Drinking Water Process
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第13期
Page:
21-27
Column:
Date of publication:
2024-07-01
- Keywords:
- gravity-driven membrane (GDM); pre-coated membrane; Al-based floc (ABF); stable flux; bio-cake layer
- Abstract:
- Gravity-driven membrane (GDM) process has the characteristics of easy operation, low energy consumption, and less maintenance. However, the stable flux is low and the performance of the bio-cake layer still needs to be improved. In this study, focusing on the key issue of the effect of GDM bio-cake layer on stable flux, the Al-based floc (ABF) pre-coated GDM (ABF-GDM) process was constructed. The membrane filtration and bio-cake layer characteristics of the ABF-GDM process were studied, and the mechanism of effect of ABF pre-coated layer on the characteristics of bio-cake layer was elucidated. The results showed that the stable flux of ABF-GDM was 6.70 L/(m2·h), which was 19.22% higher than that of GDM; the cake layer resistance and pore blocking resistance were 2.11× 1012 m-1 and 1.99 × 1011 m-1, respectively, which were 21.60% and 19.37% lower than that of GDM. The average removal rates of dissolved organic carbon and ammonia nitrogen at the stable stage were 22.10% and 89.81%, respectively, which were 7.48% and 5.92% higher than that of GDM. The ABF pre-coated cake layer could significantly improve the roughness and porosity of the GDM bio-cake layer, and reduce the EPS content. The surface porosity of ABF-GDM was 34.24%, which was 31.22% higher than that of GDM. The contents of protein and polysaccharide of EPS were 723.40 mg/m2 and 1 013.18 mg/m2, respectively, which were 22.17% and 31.92% lower than that of GDM, respectively. The ABF pre-coated layer could change the microbial community structure in the bio-cake layer, and the relative abundance of keystone taxa could directly affect the morphology structure and biochemical components of the bio-cake layer, resulting in the increase of the roughness and porosity of the ABF-GDM bio-cake layer, the decrease in EPS content, and an increase in stable flux.
Last Update:
2024-07-01