a b s t r a c tOily wastewater treatment through membrane separation is remarkably effective, but the high operation cost and poor resource recovery potential of this method necessitate the application of an integrated physical/chemical-biological oily wastewater treatment. In this study, aerobic granular sludge was applied for oily wastewater treatment from the ultrafiltration (UF) effluent of a twostage UF-reverse osmosis process. The removal efficiencies of the sludge for oil and chemical oxygen demand reached 94.1% and 85.6%, respectively. The protein concentration of extracellular polymeric substances (EPS) increased to 34.6 mg/g MLSS, and the relatively high protein/polysaccharide ratio was found to be closely related to the formation of aerobic granular sludge. In addition, protein in loosely bound-EPS was converted to tightly bound-EPS (TB-EPS), which indicated that the protein in TB-EPS could be the major factor affecting the granulation process. Separate sludge incineration could be achieved due to the lower heating value of granules was as high as 8.5 MJ/kg. Furthermore, the proposed process could enhance the treatment efficiency of the sludge incinerator and increase the amount of heat energy that could be recycled.

In this study a laboratory-scale sequencing batch bioreactor was constructed, using phenanthrene/pyrene as the sole carbon-source, to demonstrate the removal efficiencies of polycyclic aromatic hydrocarbons (PAHs) and the evolution process of a functional bacterial community. The removal rates were: COD, 51.4 to 76.3%; phenanthrene, 63.5 to 92.4%; and pyrene, 65.9 to 90.1%. Quantification analysis indicated that in sludge samples from the phenanthrene/pyrene degradation stage, the contents of 16S rRNA and ring-hydroxylating dioxygenase genes of Gram-positive and Gram-negative bacteria were 10-and 72-, 102-and 1152-, 31-and 905-fold higher, respectively, than those in seed sludge samples. Clone sequencing and evolution analysis showed that genera Comamonas, Pseudomonas, and Mycobacterium were distributed across all samples and were significant PAH-degrading populations, but some genera, such as Polaromonas and Nocardioides, were substantially enriched only when phenanthrene/pyrene was fed. Correspondingly, the functional genes nidA3, phnAc, and ndoC2 were distributed across all samples, whereas nagAc, pdoA2, and pdoA were enriched only when phenanthrene/ pyrene was fed. Water Environ. Res., 90, 2090Res., 90, (2018.