Effects of sludge retention time (SRT) on nitrogen and phosphorus removal and the microbial community in an ultrashort-SRT activated sludge system

Zhiheng Xia; Zhao Jiang; Tongtong Zhang; Binhua Liu; Mengfei Jia; Guo-Hua Liu; Lu Qi; Hongchen Wang

doi:10.1016/j.envres.2023.117510

Effects of sludge retention time (SRT) on nitrogen and phosphorus removal and the microbial community in an ultrashort-SRT activated sludge system

Environ Res. 2024 Jan 1;240(Pt 1):117510. doi: 10.1016/j.envres.2023.117510. Epub 2023 Oct 27.

Authors

Zhiheng Xia¹, Zhao Jiang², Tongtong Zhang³, Binhua Liu³, Mengfei Jia³, Guo-Hua Liu³, Lu Qi³, Hongchen Wang⁴

Affiliations

¹ Low-carbon Water Environment Technology Research Center, School of Environment & Natural Resources, Renmin University of China, Beijing, 100872, China. Electronic address: xiazhiheng1998@ruc.edu.cn.
² Low-carbon Water Environment Technology Research Center, School of Environment & Natural Resources, Renmin University of China, Beijing, 100872, China. Electronic address: jzjzdhr@126.com.
³ Low-carbon Water Environment Technology Research Center, School of Environment & Natural Resources, Renmin University of China, Beijing, 100872, China.
⁴ Low-carbon Water Environment Technology Research Center, School of Environment & Natural Resources, Renmin University of China, Beijing, 100872, China. Electronic address: whc@ruc.edu.cn.

PMID: 37890826
DOI: 10.1016/j.envres.2023.117510

Abstract

The ultrashort-sludge retention time activate sludge (USAS) process is considered promising for the recovery of energy and resource from wastewater. In this study, we developed five USAS systems (with sludge retention time (SRT) of 0.5, 1, 2, 3, and 4 d), and investigated the nitrogen and phosphorus removal, as well as the microbial community, in the USAS systems. The results revealed that the activated sludge in the USAS system with a shorter SRT can capture more organic matter from wastewater, with organic matter mineralization, capture, and loss rates of 12.9-45.9, 42.4-62.3, and 18.2-24.8%, respectively. In addition, ammonia oxidization only occurred in the USAS systems with SRTs of 3 and 4 d, and all the USAS systems with different SRTs exhibited phosphorus-removal ability. The microbial community analysis results revealed that the relative abundance of nitrifying and denitrifying bacteria (such as Thauera) increased with an increase in the SRT.

Keywords: Effect of SRT; Microbial community; Nitrogen and phosphorus removal; Ultrashort sludge retention time.

MeSH terms

Bioreactors
Nitrogen
Phosphorus
Sewage*
Waste Disposal, Fluid
Wastewater*

Substances

Sewage
Wastewater
Phosphorus
Nitrogen