Comprehensive comparison of acidic and alkaline anaerobic fermentations of waste activated sludge

Yun Chen; Roby Ruhyadi; Jinjin Huang; Wang Yan; Guoxiang Wang; Nan Shen; Wido Hanggoro

doi:10.1016/j.biortech.2020.124613

Comprehensive comparison of acidic and alkaline anaerobic fermentations of waste activated sludge

Bioresour Technol. 2021 Mar:323:124613. doi: 10.1016/j.biortech.2020.124613. Epub 2020 Dec 25.

Authors

Yun Chen¹, Roby Ruhyadi², Jinjin Huang³, Wang Yan⁴, Guoxiang Wang⁴, Nan Shen⁵, Wido Hanggoro⁶

Affiliations

¹ School of Environment, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai, People's Republic of China.
² School of Environment, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China; Solid Waste Reduction Section, Environmental Agency of Bogor Regency, Bogor Regency 16911, West Java, Indonesia.
³ School of Environment, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China.
⁴ School of Environment, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China.
⁵ School of Environment, Nanjing Normal University, Nanjing 210023, Jiangsu, People's Republic of China. Electronic address: shennan@njnu.edu.cn.
⁶ Collaborative Innovation Center on Forecast and Evaluation Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, People's Republic of China.

PMID: 33387706
DOI: 10.1016/j.biortech.2020.124613

Abstract

This study conducted a comprehensive comparison of acidic (R_5.0) and alkaline (R_10.0) anaerobic fermentations of waste activated sludge (WAS). The results showed that alkaline fermentation was able to increase biopolymer release and benefitted the production of volatile fatty acids (VFAs). However, large amounts of the released organic matter in the R_10.0 fermented liquid had low biodegradability unsuitable for the biological nutrient removal (BNR) process, resulting in increased C, nitrogen, and phosphorus loads in BNR effluent. Further, Al was more readily released than other metals and its maximum concentration reached 134.52 mg/L in R_10.0, 2.99 times higher than in R_5.0. The fermented sludge filterability was severely deteriorated at R_10.0, as indicated by the normalized capillary suction time and specific resistance to filtration. Considering these findings, VFAs from WAS via acidic fermentation may represent a suitable carbon source for direct use in the BNR process.

Keywords: Acidic fermentation; Alkaline fermentation; Metal release; Nutrients release; Sludge dewaterability.

MeSH terms

Anaerobiosis
Bioreactors*
Fatty Acids, Volatile
Fermentation
Hydrogen-Ion Concentration
Sewage*

Substances

Fatty Acids, Volatile
Sewage