Co-digestion of food waste and hydrothermal liquid digestate:Promotion effect of self-generated hydrochars  

作　　者：Mingshuai Shao Chao Zhang Xue Wang Ning Wang Qindong Chen Guangyu Cui Qiyong Xu 

机构地区：[1]Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials,School of Environment and Energy,Peking University Shenzhen Graduate School,Nanshan District,Shenzhen,518055,PR China

出　　处：《Environmental Science and Ecotechnology》2023年第3期77-87,共11页环境科学与生态技术（英文）

基　　金：supported by the Shenzhen Fundamental Research Program(No.GXWD20201231165807007-20220724202837001).

摘　　要：Hydrothermal treatment(HTT)can efficiently valorize the digestate after anaerobic digestion.However,the disposal of the HTT liquid is challenging.This paper proposes a method to recover energy through the anaerobic co-digestion of food waste and HTT liquid fraction.The effect of HTT liquid recirculation on anaerobic co-digestion performance was investigated.This study focused on the self-generated hydrochars that remained in the HTT supernatant after centrifugation.The effect of the self-generated hydrochars on the methane(CH_(4))yield and microbial communities were discussed.After adding HTT liquids treated at 140 and 180C,the maximum CH4 production increased to 309.36 and 331.61 mL per g COD,respectively.The HTT liquid exhibited a pH buffering effect and kept a favorable pH for the anaerobic co-digestion.In addition,the self-generated hydrochars with higher carbon content and large oxygen-containing functional groups remained in HTT liquid.They increased the electron transferring rate of the anaerobic co-digestion.The increased relative abundance of Methanosarcina,Syntrophomonadaceae,and Synergistota was observed with adding HTT liquid.The results of the principal component analysis indicate that the electron transferring rate constant had positive correlationships with the relative abundance of Methanosarcina,Syntrophomonadaceae,and Synergistota.This study can provide a good reference for the disposal of the HTT liquid and a novel insight regarding the mechanism for the anaerobic co-digestion.

关 键 词：Anaerobic co-digestate Electron transfer Food waste Hydrothermal treatment Microbial community Self-generated hydrochars 

分 类 号：X703[环境科学与工程—环境工程]