Enhanced anaerobic fermentation of waste activated sludge by reverse osmosis brine and composition distribution in fermentative liquid

Heliang Pang; Ling Wang; Junguo He; Pengfei Zhang; Zhongsen Yan; Yingqun Ma; Jun Nan

doi:10.1016/j.biortech.2020.123953

Enhanced anaerobic fermentation of waste activated sludge by reverse osmosis brine and composition distribution in fermentative liquid

Bioresour Technol. 2020 Dec:318:123953. doi: 10.1016/j.biortech.2020.123953. Epub 2020 Aug 2.

Authors

Heliang Pang¹, Ling Wang², Junguo He³, Pengfei Zhang², Zhongsen Yan⁴, Yingqun Ma⁵, Jun Nan⁶

Affiliations

¹ School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China; Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore.
² School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
³ School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China. Electronic address: junguohe@263.net.
⁴ College of Civil Engineering, Fuzhou University, Fuzhou 350116, PR China.
⁵ Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore.
⁶ School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.

PMID: 32927314
DOI: 10.1016/j.biortech.2020.123953

Abstract

This study reported a "treating waste by waste" strategy to dispose waste activated sludge (WAS), i.e. reverse osmosis (RO) brine-enhanced anaerobic fermentation. RO brine was hazardous by-product from seawater desalination process, which contains numerous Na⁺. After 4-day RO brine-enhanced anaerobic fermentation at Na⁺ concentration of 0.33 mol/L, 5.0 g/L VSS reduction (37.9% of VSS) was achievable, leading to considerable soluble chemical oxygen demand (SCOD) release of 349.6 mg/g VSS. Acetic acid was predominant component in SCOD (31.1%), followed by propionic, butyric, valeric acids and proteins (14.0-17.6%). Sludge solubilization and SCOD composition in the enhanced anaerobic fermentation with RO brine and NaCl agent were similar, whereas less nutrient release and extracellular polymeric substance (EPS) disruption were achieved by RO brine, attributing to the Ca²⁺&Mg²⁺-caused skeleton strengthening on EPS matrix. Such RO brine-based strategy provided environmental and economic benefits, e.g. none chemical consumption, synchronous disposal of WAS and RO brine.

Keywords: Anaerobic fermentation; Carbon recovery; Reverse osmosis brine; Sludge solubilization; Waste activated sludge.

MeSH terms

Anaerobiosis
Extracellular Polymeric Substance Matrix*
Fermentation
Hydrogen-Ion Concentration
Osmosis
Salts
Sewage*

Substances

Salts
Sewage
brine