摘要
To explore the applicability of anoxic-oxic (A/O) activated sludge process for petrochemical wastewater treatment,the relationship between bacterial community structure and pollutants loading/removal efficiencies was investigated by gas chromatograph-mass spectrometry (GC-MS),polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and other conventional techniques.It showed that when the concentrations of the influent chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) were 420~560mg/L and 64~100mg/L,respectively,the corresponding average effluent concentra-tions were 160mg/L and 55mg/L,which were 1.6 and 2.2times higher than those of the national standards in China,respectively,demonstrating the inefficient performances of A/O process.Analysis of GC-MS indicated that refractory pollutants were mainly removed by sludge adsorption,but not by biodegradation.PCR-DGGE profile analysis suggested that the biological system was species-rich,but there was apparent succession of the bacterial community structure in different locations of the A/O system.Variations of bacterial community structure and pollutant loadings had obvious influences on pollutants removal efficiencies.Thus,A/O process was inapplicable for the treatment of complicated petrochemical wastewater,and strategies such as the reinforcement of pre-treatment and two-stage A/O process were suggested.
To explore the applicability of anoxic-oxic (A/O) activated sludge process for petrochemical wastewater treatment, the relationship between bacterial community structure and pollutants loading/removal efficiencies was investigated by gas chromatograph-mass spectrometry (GC-MS), polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and other conventional techniques. It showed that when the concentrations of the influent chemical oxygen demand (COD) and ammonia nitrogen (NH4+^-N) were 420-560 mg/L and 64-100 mg/L, respectively, the corresponding average effluent concentrations were 160 mg/L and 55 mg/L, which were 1.6 and 2.2 times higher than those of the national standards in China, respectively, demonstrating the inefficient performances of A/O process. Analysis of GC-MS indicated that refractory pollutants were mainly removed by sludge adsorption, but not by biodegradation. PCR-DGGE profile analysis suggested that the biological system was species-rich, but there was apparent succession of the bacterial community structure in different locations of the A/O system. Variations of bacterial community structure and pollutant loadings had obvious influences on pollutants removal efficiencies. Thus, A/O process was inapplicable for the treatment of complicated petrochemical wastewater, and strategies such as the reinforcement of pre-treatment and two-stage A/O process were suggested.
基金
Project supported by the National Basic Research Program(973)of China(No.2004CB418505)
the Science and Technology Devel-opment Program of Heilongjiang Province(No.CC05S301),China
关键词
废水处理
流床反应器
氧化处理
污水处理
Petrochemical wastewater, Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE),Anoxic-oxic (A/O) process, Applicability,