Fate of antibiotic resistance genes during anaerobic digestion of sewage sludge: Role of solids retention times in different configurations

• Published in: Bioresource technology Vol. 274; pp. 488 - 495
• Main Authors: Zhang, Junya, Liu, Jibao, Lu, Tiedong, Shen, Peihong, Zhong, Hui, Tong, Juan, Wei, Yuansong
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2019
• Subjects: Anaerobic digestion; Antibiotic resistance genes; Configuration; Sewage sludge; Solids retention times; Solids retention times; Configuration; Antibiotic resistance genes; Sewage sludge; Anaerobic digestion
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.12.008

[Display omitted] •SRT significantly influenced the ARGs fate in different configurations.•The role of SRT on the ARGs fate varied from ARG types and reactor configurations.•Shorter SRT availed the ARGs reduction for CK and two-stage digestion.•One-stage digestion of pretreated sludge need longer SRT for the ARGs reduction.•Co-selection from heavy metals contributed the most to ARGs fate response to SRT. In this study, three anaerobic digestion experiments were established to investigate the effects of solids retention times (SRT) on the fate of antibiotic resistance genes (ARGs) including anaerobic digestion of sewage sludge (CK), one-stage anaerobic digestion of microwave pretreatment sludge (MW) and two-stage anaerobic digestion of microwave pretreatment sludge (Acid stage and CH4 stage). The response of ARGs to the SRT varied significantly from ARG types and reactor configurations. Shorter SRT could avail the ARGs reduction for CK and two-stage digestion, while MW need longer SRT for the ARGs reduction. Concerning the variance of microbial community caused by reactor configurations, the role of SRT was limited. The partial redundancy analysis and structural equation models analysis indicated that the role of SRT on the ARGs fate could be attributed the most to the co-selection from heavy metals.