Enzyme-enhanced acidogenic fermentation of waste activated sludge : Insights from sludge structure, interfaces, and functional microflora

Copyright © 2023. Published by Elsevier Ltd..

Anaerobic fermentation is widely installed to recovery valuable resources and energy as CH4 from waste activated sludge (WAS), and its implementation in developing countries is largely restricted by the slow hydrolysis, poor efficiency, and complicate inert components therein. In this study, enzyme-enhanced fermentation was conducted to improve sludge solubilization from 283 to 7728 mg COD/L and to enhance volatile fatty acids (VFAs) yield by 58.6 % as compared to the conventional fermentation. The rapid release of organic carbon species, especially for tryptophan- and tyrosine-like compounds, to outer layer of extracellular polymeric substance (EPS) occurred to reduce the structural complexity and improve the sludge biodegradability towards VFAs production. Besides, upon enzymatic pretreatment the simultaneous exposure of hydrophilic and hydrophobic groups on sludge surfaces increased the interfacial hydrophilicity. By quantitative analysis via interfacial thermodynamics and XDLVO theory, it was confirmed that the stronger hydrophilic repulsion and energy barriers in particle interface enhanced interfacial mass transfer and reactions involved in acidogenic fermentation. Meanwhile, these effects stimulate the fermentation functional microflora and predominant microorganism, and the enrichment of the hydrolytic and acid-producing bacteria in metaphase and the proliferation of acetogenic bacteria, e.g., Rubrivivax (+9.4 %), in anaphase also benefits VFAs formation. This study is practically valuable to recovery valuable VFAs as carbon sources and platform chemicals from WAS and agriculture wastes.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:249

Enthalten in:

Water research - 249(2024) vom: 01. Jan., Seite 120889

Sprache:

Englisch

Beteiligte Personen:

Song, Ge [VerfasserIn]
Zhao, Shunan [VerfasserIn]
Wang, Jiaqi [VerfasserIn]
Zhao, Kai [VerfasserIn]
Zhao, Jing [VerfasserIn]
Liang, He [VerfasserIn]
Liu, Ruiping [VerfasserIn]
Li, Yu-You [VerfasserIn]
Hu, Chengzhi [VerfasserIn]
Qu, Jiuhui [VerfasserIn]

Links:

Volltext

Themen:

7440-44-0
Acidogenic fermentation
Carbon
Enzyme
Fatty Acids, Volatile
Interfacial thermodynamics
Journal Article
Sewage
Transcriptomic community
Volatile fatty acids
Waste activated sludge

Anmerkungen:

Date Completed 03.01.2024

Date Revised 03.01.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.watres.2023.120889

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM365343374