Gas-water alternate membrane bioreactor for domestic sewage treatment

The treatment efficiency by the gas-water alternate membrane bioreactor (AMBR) on domestic sewage was investigated through a pilot-scale study in order to get better application effect in the practical engineering. The results showed that: AMBR had good COD and NH₄⁺-N removal effect when the C/N ratio of raw domestic sewage was 4, and the COD and NH₄⁺-N concentration in effluent under 20 mg/L and 5 mg/L. But it's not good at TN removal because of its low C/N ratio, and the TN concentration in effluent was 22.4 mg/L. When the C/N ratio of raw water increased to 6 according to adding glucose in raw domestic sewage, the TN removal efficiency by AMBR was increased to 66%, and the effluent TN was only 13 mg/L, which met the First A-level requirement of China. Meanwhile, the COD and NH₄⁺-N removal effect by AMBR was unaffected by the change of the raw water's C/N ration. The trans-membrane pressure was maintained about-20 kPa indicated that AMBR also had good membrane fouling alleviating effect.