Different Types of Inoculated Sludge for Chemical Wastewater Treatment: Acclimation and Microbial Community

A laboratory-scale reactor for hydrolytic acidification-biological contact oxidation (A/O) was constructed and inoculated with different types of sludge to treat synthetic chemical wastewater. Biodegradation of degradation-resistant organic matters, such as epoxy propane, glycerol and aniline, in saline water were evaluated, and acclimation of chemical and sewage seeding sludge was contrastively analysed. An average COD reduction rate of 93% by A/O reactor was achieved after the 22 d and 31 d of acclimation of chemical and sewage seeding sludge, respectively. Salt-tolerance acclimation of chemical seeding sludge required 35 d and 14 g/L NaCl for effective pollution degradation, whereas, chemical sludge required 32 d and had salt-tolerance of 16 g/L NaCl. The microbial community structure differed between chemical and sewage seeding sludge. Sewage sludge presented higher average Shannon diversity index (3.34) and more uniform microbial distribution than chemical sludge. The results can provide the basis for selection, cultivation and acclimation of inoculation sludge for field debugging of treating chemical wastewater through biological membrane method.