TY - JOUR
T1 - Hydrochar mediated anaerobic digestion of bio-wastes
T2 - Advances, mechanisms and perspectives
AU - Xu, Qiuxiang
AU - Yang, Guojing
AU - Liu, Xuran
AU - Wong, Jonathan W.C.
AU - Zhao, Jun
N1 - Funding Information:
This work was partly funded by the Open Project of Zhejiang Provincial Top Key Discipline of Biological Engineering ( KF2020008 ), Natural Science Foundation of Zhejiang Province and Ningbo City ( LY21E080028 and 202003N4328 ) and Environment and Conservation Fund , Hong Kong Administrative Region ( ECF Project 46/2020, 09/2021 ).
Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/8/1
Y1 - 2023/8/1
N2 - Bio-wastes treatment and disposal has become a challenge because of their increasing output. Given the abundant organic matter in bio-wastes, its related resource treatment methods have received more and more attention. As a promising strategy, anaerobic digestion (AD) has been widely used in the treatment of bio-wastes, during which not only methane as energy can be recovered but also their reduction can be achieved. However, AD process is generally disturbed by some internal factors (e.g., low hydrolysis efficiency and accumulated ammonia) and external factors (e.g., input pollutants), resulting in unstable AD operation performance. Recently, hydrochar was wildly found to improve AD performance when added to AD systems. This review comprehensively summarizes the research progress on the performance of hydrochar-mediated AD, such as increased methane yield, improved operation efficiency and digestate dewatering, and reduced heavy metals in digestate. Subsequently, the underlying mechanisms of hydrochar promoting AD were systematically elucidated and discussed, including regulation of electron transfer (ET) mode, microbial community structure, bio-processes involved in AD, and reaction conditions. Moreover, the effects of properties of hydrochar (e.g., feedstock, hydrothermal carbonization (HTC) temperature, HTC time, modification and dosage) on the improvement of AD performance are systematically concluded. Finally, the relevant knowledge gaps and opportunities to be studied are presented to improve the progress and application of the hydrochar-mediated AD technology. This review aims to offer some references and directions for the hydrochar-mediated AD technology in improving bio-wastes resource recovery.
AB - Bio-wastes treatment and disposal has become a challenge because of their increasing output. Given the abundant organic matter in bio-wastes, its related resource treatment methods have received more and more attention. As a promising strategy, anaerobic digestion (AD) has been widely used in the treatment of bio-wastes, during which not only methane as energy can be recovered but also their reduction can be achieved. However, AD process is generally disturbed by some internal factors (e.g., low hydrolysis efficiency and accumulated ammonia) and external factors (e.g., input pollutants), resulting in unstable AD operation performance. Recently, hydrochar was wildly found to improve AD performance when added to AD systems. This review comprehensively summarizes the research progress on the performance of hydrochar-mediated AD, such as increased methane yield, improved operation efficiency and digestate dewatering, and reduced heavy metals in digestate. Subsequently, the underlying mechanisms of hydrochar promoting AD were systematically elucidated and discussed, including regulation of electron transfer (ET) mode, microbial community structure, bio-processes involved in AD, and reaction conditions. Moreover, the effects of properties of hydrochar (e.g., feedstock, hydrothermal carbonization (HTC) temperature, HTC time, modification and dosage) on the improvement of AD performance are systematically concluded. Finally, the relevant knowledge gaps and opportunities to be studied are presented to improve the progress and application of the hydrochar-mediated AD technology. This review aims to offer some references and directions for the hydrochar-mediated AD technology in improving bio-wastes resource recovery.
KW - Anaerobic digestion
KW - Energy recovery
KW - Hydrochar
KW - Regulation mechanism
KW - Wastes valorization
UR - http://www.scopus.com/inward/record.url?scp=85153844987&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2023.163829
DO - 10.1016/j.scitotenv.2023.163829
M3 - Review article
AN - SCOPUS:85153844987
SN - 0048-9697
VL - 884
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 163829
ER -
