Alkaline aided thermophiles pretreatment of waste activated sludge to increase short chain fatty acids production: Microbial community evolution by alkaline on hydrolysis and fermentation

Chun-Xue Yang; Shuai Zhao; Ze-Chong Guo; Wen-Zong Liu; Ling Wang; Shao-Peng Yu; Bao-Ling Liu; Xue Cong

doi:10.1016/j.envres.2020.109503

Alkaline aided thermophiles pretreatment of waste activated sludge to increase short chain fatty acids production: Microbial community evolution by alkaline on hydrolysis and fermentation

Environ Res. 2020 Jul:186:109503. doi: 10.1016/j.envres.2020.109503. Epub 2020 Apr 12.

Authors

Chun-Xue Yang¹, Shuai Zhao², Ze-Chong Guo³, Wen-Zong Liu⁴, Ling Wang⁵, Shao-Peng Yu¹, Bao-Ling Liu¹, Xue Cong¹

Affiliations

¹ Heilongjiang Cold Region Wetland Ecology and Environment Research Key Laboratory, School of Geography and Tourism, Harbin University, Harbin, China.
² College of Animal Science and Technology, Northeast Agricultural University, Harbin, China.
³ School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China.
⁴ School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen, China. Electronic address: liuwz0326@126.com.
⁵ State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, China.

PMID: 32302867
DOI: 10.1016/j.envres.2020.109503

Abstract

Adding alkaline into an anaerobic waste activated sludge (WAS) fermentation with thermophilic bacteria pretreatment could efficiently improve short-chain fatty acids (SCFAs) accumulation to 3550 ± 120 mg COD/L. The acidification rate in combined test was 21.2%, while that was 15.6% and 10.7% in sole thermophilic bacteria pretreatment and control tests respectively. Four distinct groups of microbes could be identified with noticeable shifts using the combined pretreatments, and tremendous effects were analyzed on organic content especially of the soluble proteins and SCFAs concentrations. Particularly, alkaline addition would significantly change the functional microbial structures, including the decrease of Caloramator with the function of thermophilic proteolytic and the increase of Acidobacteria TM7 and Petrimonas sp. The results above suggested that alkaline addition could decrease the hydrolytic substances consume by thermotolerance bacteria and final improve SCFAs accumulation in fermentation process.

Keywords: Alkaline; Pretreatment; Short chain fatty acids (SCFAs); Thermophilic bacteria; Waste activated sludge (WAS).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Fatty Acids, Volatile
Fermentation
Hydrogen-Ion Concentration
Hydrolysis
Microbiota*
Sewage*

Substances

Fatty Acids, Volatile
Sewage