Triclosan facilitates the recovery of volatile fatty acids from waste activated sludge

Mei Zou; Mengyu Yin; Yayi Yuan; Dongbo Wang; Weiping Xiong; Xiao Yang; Yaoyu Zhou; Hongbo Chen

doi:10.1016/j.scitotenv.2020.142336

Triclosan facilitates the recovery of volatile fatty acids from waste activated sludge

Sci Total Environ. 2021 Feb 1:754:142336. doi: 10.1016/j.scitotenv.2020.142336. Epub 2020 Sep 14.

Authors

Mei Zou¹, Mengyu Yin¹, Yayi Yuan¹, Dongbo Wang², Weiping Xiong², Xiao Yang³, Yaoyu Zhou⁴, Hongbo Chen⁵

Affiliations

¹ College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
² College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
³ Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
⁴ College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
⁵ College of Environment and Resources, Xiangtan University, Xiangtan 411105, China. Electronic address: chenhongbo@hnu.edu.cn.

PMID: 33254905
DOI: 10.1016/j.scitotenv.2020.142336

Abstract

The emergence of triclosan (TCS) in the environment has caused extensive concern, but its role in waste activated sludge (WAS) anaerobic fermentation (AF) is still uncertain. This work investigated the impact of TCS on volatile fatty acids (VFAs) recycling from WAS. The results showed that TCS of 200 mg/kg TSS increased the maximum VFA accumulation from 7284 to 15,083 mg COD/L. The increase in total VFA production is attributed to the massive increase in acetic acid. Mechanism exploration showed that TCS promotes WAS solubilization by facilitating cell breakage and extracellular polymeric substances disruption, and stimulates AF by enhancing the activity of key enzymes among all stages. TCS promotes acidification stronger than methanogenesis, which makes VFA production faster than consumption, leading to increased VFA accumulation. These findings provide novel insights for revealing the role of TCS in WAS resource recovery, and offer thoughts for the selective production of final recycling products of TCS-containing WAS.

Keywords: Anaerobic fermentation; Triclosan; Volatile fatty acids; Waste activated sludge.