Unveiling the mechanisms of Fe(Ⅲ)-loaded chitosan composite(CTS-Fe)in enhancing anaerobic digestion of waste activated sludge  

作　　者：Boaiqi Zhang Ziwen Zhao RuiMa Nan Chen Zhe Kong Zhongfang Lei Zhenya Zhang 

机构地区：[1]Graduate School of Life and Environmental Sciences,University of Tsukuba,1-1-1 Tennodai,Tsukuba,Ibaraki 305-8572,Japan [2]The Key Laboratory of Water and Sediment Sciences,Ministry of Education/State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems/College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China [3]South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou 510345,China [4]School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,China [5]School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou 215009,China

出　　处：《Journal of Environmental Sciences》2024年第4期200-211,共12页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52200031)。

摘　　要：Anaerobic digestion(AD)of waste activated sludge(WAS)is usually limited by the low generation efficiency of methane.Fe(Ⅲ)-loaded chitosan composite(CTS-Fe)have been reported to effectively enhanced the digestion of WAS,but its role in promoting anaerobic sludge digestion remains unclear.In present study,the effects of CTS-Fe on the hydrolysis and methanogenesis stages of WAS anaerobic digestion were investigated.The addition of CTSFe increased methane production potential by 8%-23%under the tested conditions with the addition of 5-20 g/L CTS-Fe.Besides,the results demonstrate that the addition of CTS-Fe could effectively promote the hydrolysis of WAS,evidenced by lower protein or polysaccharides concentration,higher soluble organic carbon in rector adding CTS-Fe,as well as the increased activity of extracellular hydrolase with higher CTS-Fe concentration.Meanwhile,the enrichment of Clostridia abundance(iron-reducing bacteria(IRBs))was observed in CTS-Fe adding reactor(8.9%-13.8%),which was higher than that in the control reactor(7.9%).The observation further suggesting the acceleration of hydrolysis through dissimilatory iron reduction(DIR)process,thus providing abundant substrates for methanogenesis.However,the presence of CTS-Fe was inhibited the acetoclastic and hydrogenotrophic methanogenesis process,which could be ascribed to the Fe(Ⅲ)act as electron acceptor coupled to methane for anaerobic oxidation.Furthermore,coenzyme F420 activity in the CTS-Fe added reactor was 34.9% lower than in the blank,also abundance of microorganisms involved in hydrogenotrophic methanogenesis was decreased.Results from this study could provide theoretical support for the practical applications of CTS-Fe.

关 键 词：Chitosan-Fe(Ⅲ)composite METHANOGENESIS Dissimilatory iron reduction Enzyme activity Microbial community structure 

分 类 号：TB33[一般工业技术—材料科学与工程] X703[环境科学与工程—环境工程]