標題: Recycling of spent filter backwash water using coagulation-assisted membrane filtration: effects of submicrometre particles on membrane flux
作者: Huang, Chihpin
Lin, Jr-Lin
Wu, C. L.
Chu, C. P.
環境工程研究所
Institute of Environmental Engineering
關鍵字: coagulation;membrane filtration;MF;spent filter backwash water
公開日期: 2010
摘要: Membrane separation technology has been widely used for recycling of spent filter backwash water (SFBW) in water treatment plant. Membrane filtration performance is subject to characteristics of the particles in the SFBW. A bench-scale microfiltration (MF) coupled with pre-coagulation was set up to evaluate the recovery efficiency of SFBW. Effect of particle size distribution and zeta potential of the coagulated SFBW on the membrane filtration as well as the coagulation strategies were investigated. Pore clogging was more severe on the membrane with 1.0 mu m pore size than on the membrane with 0.5 mu m pore size due to the fact that submicrometre particles are dominant and their diameters are exactly closed to the pore size of the MF membrane. Pre-settling induced more severe irreversible fouling because only the submicrometre particles in the water become predominant after settling, resulting in the occurrence of more acute pore blocking of membrane. By contrast, pre-coagulation mitigates membrane fouling and improves membrane flux via enlarging particle size on membrane surface. The variations of zeta potential in response to coagulant dosing as well as fractal dimension were also compared with the performance of the subsequent filtration. The result showed that pre-coagulation induced by charge neutralization at the optimum dosage where the zeta potential is around zero leads to the optimal performance of the subsequent membrane filtration for SFBW recycling. At such condition, the fractal dimension of coagulated flocs reached minimum.
URI: http://hdl.handle.net/11536/6002
http://dx.doi.org/10.2166/wst.2010.146
ISSN: 0273-1223
DOI: 10.2166/wst.2010.146
期刊: WATER SCIENCE AND TECHNOLOGY
Volume: 61
Issue: 8
起始頁: 1923
結束頁: 1929
顯示於類別:期刊論文