Enhanced biodegradation of pyridine using sequencing batch biofilm reactor under intermittent micro-aerobic condition

• Published in: Environmental technology Vol. 41; no. 8; pp. 1034 - 1043
• Main Authors: Sun, Guoping, Wan, Junfeng, Sun, Yichen, Xie, Yunfei, Ren, Shengtao, Wang, Yan
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 02.04.2020; Taylor & Francis Ltd
• Subjects: Aerobic conditions; Aerobic microorganisms; Ammonium; Anaerobic conditions; Azotobacter; Biodegradation; biodegradation pathway; Biodegradation, Environmental; Biofilms; Bioreactors; Dominant species; intermittent micro-aerobic condition; kinetic study; Microorganisms; Next-generation sequencing; Pyridine; Pyridines; Reactors; Sequence analysis; sequencing batch biofilm reactor (SBBR); Sulfate reduction; Waste Disposal, Fluid; Wastewater; intermittent micro-aerobic condition; sequencing batch biofilm reactor (SBBR); kinetic study; Pyridine; biodegradation pathway
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330.2018.1518995

A sequencing batch biofilm reactor under intermittent micro-aerobic or anaerobic conditions was investigated to remove pyridine at various concentrations from synthetic wastewater. The results showed that over 98% of pyridine (influent concentration ≤200 mg L −1 ) was degraded under intermittent micro-aerobic condition, while about 21% of pyridine was removed under anaerobic condition. Additionally, at least 60% of nitrogen located in the pyridine ring was transformed to ammonium. At the same time, the sulphate reduction was obviously inhibited under intermittent micro-aerobic conditions. The microscopic observation showed that abundant microorganisms were attached on the surface or inside of porous biocarriers under intermittent micro-aerobic conditions after a short-term period of operation. High-throughput sequencing analysis demonstrated that Azotobacter, Rhodobacteraceae and Tolumonas were the dominant species in the intermittent micro-aerobic system. The kinetic study at steady period showed that pyridine degradation was fitted well with the pseudo-first-order model (R 2  > 0.96). The two possible intermediate products were identified and the possible biodegradation pathway of pyridine was proposed under micro-aerobic condition.