Pilot-scale hybrid coagulation/membrane bioreactor (HCMBR) for textile dyeing wastewater advanced treatment

A pilot-scale hybrid coagulation/membrane bioreactor (HCMBR) was investigated for real textile dyeing wastewater advanced treatment. Poly-aluminum chloride (PACI) was selected and used in the experiments. The HCMBR performed well in the removal of organic matter and total phosphate (TP). As compared to membrane bioreactor (MBR), HCMBR achieved much higher removal efficiencies in CODcr, UV254 and TP, due to PACI coagulation in the bioreactor. In light of relative hydrophobicity and extracellular polymeric substances (EPS) content variation, the results indicated that EPS was a significant factor affecting membrane fouling. The trans-membrane pressure (TMP) of HCMBR developed much slower than that of MBR, which revealed that coagulation with PACI in the membrane bioreactor could alleviate membrane fouling. PACI addition was practically feasible for real textile dyeing wastewater advanced treatment without large excess sludge production. Based on above results, HCMBR is being considered to be technically and economically promising combination for real textile dyeing wastewater advanced treatment.