Study on treatment of chemical plant wastewater by using a integrated anaerobic–aerobic bioreactor

Abstract

ABSTRACT In this work, a new type of integrated anaerobic aerobic bioreactor (IAAB) was formed by optimizing the structure of the anaerobic baffle bioreactor and aerobic biological contact oxidation pool. IAAB was used to treat the production wastewater of a chemical plant. The whole process was divided into two stages of domestication and stable operation. With increasing the proportion of chemical wastewater, the total amount of extracellular polymeric substances increased, and the ratio of protein to polysaccharide decreased. Dehydrogenase activity of anaerobic granular sludge in each compartment increased about 1.5 times with time, and decreased about 42% along the flow direction from the first compartment to the third compartment. The coenzyme F420 increased about 4 times with time, and increased about 1.2 times along the flow direction. The IAAB showed excellent removal rate of chemical oxygen demand (85%), ammonia nitrogen (94%), nitrobenzenes (98%).