Acids production enhancement technology for sludge fermentation and its application potential

FENG Chen; ZHANG Han; GAO Jinhua; WANG Jiawei; WEN Yang; REN Zhengran; LI Xiangkun

doi:10.13205/j.hjgc.202506006

Volume 43 Issue 6

Jun. 2025

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Article Navigation > ENVIRONMENTAL ENGINEERING > 2025 > 43(6): 51-64

FENG Chen, ZHANG Han, GAO Jinhua, WANG Jiawei, WEN Yang, REN Zhengran, LI Xiangkun. Acids production enhancement technology for sludge fermentation and its application potential[J]. ENVIRONMENTAL ENGINEERING , 2025, 43(6): 51-64. doi: 10.13205/j.hjgc.202506006

Citation:

FENG Chen, ZHANG Han, GAO Jinhua, WANG Jiawei, WEN Yang, REN Zhengran, LI Xiangkun. Acids production enhancement technology for sludge fermentation and its application potential[J]. ENVIRONMENTAL ENGINEERING , 2025, 43(6): 51-64. doi: 10.13205/j.hjgc.202506006

Citation:

FENG Chen, ZHANG Han, GAO Jinhua, WANG Jiawei, WEN Yang, REN Zhengran, LI Xiangkun. Acids production enhancement technology for sludge fermentation and its application potential[J]. ENVIRONMENTAL ENGINEERING , 2025, 43(6): 51-64. doi: 10.13205/j.hjgc.202506006

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Acids production enhancement technology for sludge fermentation and its application potential

doi: 10.13205/j.hjgc.202506006

1. School of Civil Engineering and Transportation, Hebei University of Technology, Tianjin 300401, China;
2. Beijing Municipal Sewage Resource Engineering Technology Research Center, Science and Technology Research and Development Center of Beijing Urban Drainage Group Co., Ltd., Beijing 100124, China

Received Date: 2024-07-15
Accepted Date: 2024-08-24
Rev Recd Date: 2024-08-08

Abstract

Abstract

The production of volatile fatty acids （VFAs） through anaerobic fermentation of sludge represents a promising route for the resource utilization of sludge. VFAs are not only precursors for a variety of industrial products but also serve as supplementary carbon sources in biological wastewater treatment processes. Nevertheless， its widespread application is hampered by factors such as low acid production yields and instability of the fermentation process. Consequently， investigating strategies to enhance the efficiency of sludge fermentation for acid production and the application potential of the fermentation broth has become a focal point in research. Current research predominantly focuses on the mechanisms and influencing factors of sludge fermentation for acid production， with a notable gap in the systematic summary of enhancement methods for sludge acid production and the subsequent applications of the fermentation broth. This paper provides an overview of the mechanisms of anaerobic fermentation of sludge for acid production and provides a comprehensive summary of the advantages and limitations of four common enhancement strategies for sludge acid production： pretreatment， membrane technology， alkaline fermentation， and co-fermentation. Additionally， it introduces on the application pathways of the sludge fermentation broth under the aforementioned enhancement strategies， including its use as a raw material for synthesizing polyhydroxyalkanoates （PHAs）， medium-chain fatty acids （MCFAs）， and bioenergy， as well as its potential in the preparation of microbial fuel cells （MFC） and as a carbon source for nitrogen and phosphorus removal in wastewater treatment. Finally， the paper identifies the challenges and deficiencies in the current techniques for enhancing sludge acid production and the application fields of the fermentation broth， and offers insights into future research directions， aiming to provide a reference for improving the recovery rate of sludge resources and the utilization efficiency of fermentation products.
- sludge,
- anaerobic fermentation,
- enhanced acid production,
- volatile fatty acids （VFAs）,
- application

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References(95)

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