ABSTRACT
A coagulation–microfiltration combination process was used in treatment of simulative surface water. The effects of operational conditions such as filtration time, ceasing time and aeration intensity on the membrane permeability and organic removals were investigated. Experiment results showed that the membrane permeability could be improved through changing the operational conditions. Decreasing the filtration time or increasing the ratio of filtration time/ceasing time was favorable to enhance the membrane permeability. As the aeration intensity increased, the membrane permeability was also enlarged to some extent, but was not improved obviously anymore when the aeration intensity was over the critical value of around 4 m3 h−1. Different wash methods to remove membrane fouling were attempted. The results suggested that coagulation in the process mainly led to change of the deposit cake-caused membrane fouling, which could be physically removed by surface wash. Organic removals, in terms of OC and UV254, apparently varied with the operational conditions. An inverse relationship between organic removals and membrane permeability was found. Lower membrane permeability led to higher OC and UV254 removals.