Simultaneous biodegradation of phenolics and petroleum hydrocarbons from semi-coking wastewater: Construction of bacterial consortium and their metabolic division of labor

Phenols and petroleum hydrocarbons were the main contributors to COD in semi-coking wastewater, and their removal was urgent and worthwhile. The microbial strains were selected to construct microbial community for the wastewater treatment. The concentration of phenols was decreased from 2450 ± 1.2 mg/L to 200 ± 0.9 mg/L, and the removal rate of petroleum hydrocarbons was up to 97.08 ± 0.09 % by microorganisms. After phenolic compounds with high toxicity were removed by bioaugmentation, the treated semi-coking wastewater was more biodegradable, and its water quality has been significantly improved. Through GC-MS and high-through sequencing technology, the metabolic division of labor in degradation of phenols, ring-cleavage of aromatic compounds, mineralization of metabolites was further revealed. The microbial community consisting of Pseudomonas stutzeri N2 and Rhodococcus qingshengii FF could effectively and simultaneously remove phenols and petroleum hydrocarbons, and these two strains possess great potential of being applied in aerobic biological treatment process of large-scale semi-coking wastewater.