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To verify the feasibility of membrane micro-filtration process to treat the sand-filter backwash wastewater and the sediment sludge withdrawn from the coagulation–flocculation–settling tank, a multi-lumen monolith ceramic membrane module was applied in a test pilot plant. The ceramic membrane filtration was operated very stably at the filtration flux of 4 m/day when the sand-filter backwash wastewater was fed. The membrane filtration was also operated very stably at the flux of 2 m/day when the mixture of the sand-filter backwash wastewater and the sediment sludge was fed. The level of these substances in the membrane filtrate was very low and met drinking water standards.

The removal of bisphenol A (BPA) from drinking water by hollow fiber microfiltration (MF) membrane using dead-end model was investigated. The experiment was focused on the effect of various factors including BPA initial concentration, pH, ionic strength and organic matter on removal efficiency. Adsorption plays a significant role in BPA removal in MF filtration. The results showed that MF could remove BPA effectively. A higher removal was obtained at the beginning of the filtration, and the removal efficiency decreased to around 20% when the membrane became saturated due to adsorption of BPA onto the MF membrane. As pH of solution approached to pKa (9.6–11.3) of BPA, BPA removal efficiency dropped significantly. The effect of ionic strength on BPA removal was negligible. The presence of natural organic matter (NOM) demonstrated no observable impact on BPA removal. After filtration, the backwash could recover removal efficiency effectively.

Surface water was purified by ultrafiltration membrane to produce drinking water. The membrane flux decreases with increasing turbidity and there is a somehow linear relationship between membrane flux and the log of turbidity. Mathematical model was built to predict the membrane flux based on this. The parameters which concerned the model were raw water quality (turbidity), transmembrane pressure (ΔP) and temperature. The result showed that the model can well predict the membrane flux.

The removal of bisphenol A (BPA) from drinking water by ultrafiltration membrane (UF) using dead-end model was investigated. The experiment was focused on the effect of various factors on removal efficiency with respect to BPA initial concentration, molecular weight cut offs (MWCOs) of membrane, pH, ionic strength and organic matter. The results showed that UF could remove BPA effectively. UF with 2000–10,000 MWCOs removed BPA by over 92%, with initial concentration of BPA ranging from 100 to 600 μg/L. As pH of solution approached to pKa (9.6–11.3) of BPA, BPA removal efficiency dropped significantly. The effect of ionic strength on BPA removal was not found. The influence of humic acid on BPA removal was minor. It can be concluded that adsorption play a significant role in BPA removal in UF process.