Improving the co-digestion performance of waste activated sludge and wheat straw through ratio optimization and ferroferric oxide supplementation

•Co-digestion of WAS and WS increased methane production.•Addition of Fe3O4 further increased methane production.•Co-digestion of WAS and WS reduced the acidic pH of WS mono-digestion.•Addition of Fe3O4 further reduced the acidic pH of co-digestion of WAS and WS.•Fe3O4 changed the fermentative type...

Full description

Saved in:
Bibliographic Details
Published inBioresource technology Vol. 267; pp. 591 - 598
Main Authors Zhao, Zisheng, Li, Yang, Quan, Xie, Zhang, Yaobin
Format Journal Article
LanguageEnglish
Published England Elsevier Ltd 01.11.2018
Subjects
Acidic pH
activated sludge
anaerobic digestion
bacteria
carbon nitrogen ratio
Co-digestion
Ethanol-type fermentation
Fe3O4
iron oxides
methane production
propionic acid
volatile fatty acids
wheat straw
Fe3O4
Acidic pH
Co-digestion
Ethanol-type fermentation
FeO
Online AccessGet full text

Cover

More Information
Summary:•Co-digestion of WAS and WS increased methane production.•Addition of Fe3O4 further increased methane production.•Co-digestion of WAS and WS reduced the acidic pH of WS mono-digestion.•Addition of Fe3O4 further reduced the acidic pH of co-digestion of WAS and WS.•Fe3O4 changed the fermentative type of the co-digestion of WAS and WS. Low anaerobic digestion efficiency of wheat straw (WS) has been an intractable problem owing to its high C/N ratio and complex structure. In this study, co-digestion of WS and waste activated sludge (WAS) at different ratios was performed to identify conditions that would elevate the acidic pH and increase methane production. The results showed that using a 1:1 ratio of WS and WAS, methane production in the co-digester was 26.9% higher than the sum of equal WAS and WS mono-digestion. When Fe3O4 was added to the co-digester, the acidic pH was further relieved and the anaerobic digestion efficiency was additionally enhanced. Microbial analysis showed that the ethanol-type fermentative bacterial genus Ethanoligenens was enriched in the WAS + WS-Fe3O4 reactor, in which the production of propionate was notably reduced, indicating that Fe3O4 could prevent the accumulation of volatile fatty acids by changing the types of fermentative bacteria present and promote anaerobic digestion efficiency.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0960-8524
1873-2976
1873-2976
DOI:10.1016/j.biortech.2018.07.052