Microbial communities and biodegradation in lab-scale BTEX-contaminated groundwater remediation using an oxygen-releasing reactive barrier.
To remediate benzene, toluene, ethylbenzene and xylene (BTEX) -contaminated groundwater, a biotreatment process including biostimulation and bioaugmentation was simulated using oxygen-releasing reactive barriers (ORRB) and water with added BTEX in a lab-scale system. The results showed that the capability for BTEX removal decreases in the order of benzene, toluene, p-xylene, ethylbenzene for both added-nitrogen and no-added-nitrogen under BTEX concentrations at 30 mg l(-1). The removal efficiencies in ORRB systems were higher in the nitrogen-added condition for biostimulation compared with the no-nitrogen-added condition; moreover, an increased pattern for removal was observed during the bioaugmentation process. The oxygen content was found to be inversely proportional to the distance from the ORRB, as evidenced by observing that the average bacteria densities were two orders higher when located at 15 cm compared with 30 cm from the ORRB. The microbial community structure was similar in both cases of added-nitrogen and the no-added-nitrogen conditions.
Lin
Chi-Wen
CW
Department of Safety, Health and Environmental Engineering, National Yunlin University of Science and Technology, 123 University Road, Sect. 3, Douliou, Yunlin 64002, Taiwan, ROC. linwen@yuntech.edu.tw
Chen
Li-Hsuan
LH
I
Yet-Pole
YP
Lai
Chi-Yung
CY
D000465:Algorithms; D001673:Biodegradation, Environmental; D001709:Biotechnology / Q000379:methods*; D016000:Cluster Analysis; D004867:Equipment Design; D007218:Industrial Microbiology / Q000379:methods; D009584:Nitrogen / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D012336:RNA, Ribosomal, 16S / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014871:Water Microbiology; D014874:Water Pollutants, Chemical; D018508:Water Purification / Q000379:methods*
D012336:RNA, Ribosomal, 16S; D014874:Water Pollutants, Chemical; D014867:Water; D009584:Nitrogen; D010100:Oxygen