Peracetic acid(PAA)-based pretreatment effectively improves medium-chain fatty acids(MCFAs)production from sewage sludge  

作　　者：Yufen Wang Haixiao Guo Xuecheng Li Xueming Chen Lai Peng Tingting Zhu Peizhe Sun Yiwen Liu 

机构地区：[1]School of Environmental Science and Engineering,Tianjin University,Tianjin,300072,China [2]Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology,College of Environment and Safety Engineering,Fuzhou University,Fujian,350116,China [3]Hubei Key Laboratory of Mineral Resources Processing and Environment,Wuhan University of Technology,Luoshi Road 122,Wuhan,Hubei,430070,China [4]School of Resources and Environmental Engineering,Wuhan University of Technology,Luoshi Road 122,Wuhan,Hubei,430070,China

出　　处：《Environmental Science and Ecotechnology》2024年第4期154-166,共13页环境科学与生态技术（英文）

基　　金：funded by the National Natural Science Foundation of China through project 52000135;The first author is funded by the Shanghai Tongji Gao Tingyao Environmental Science&Technology Development Foundation.

摘　　要：Peracetic acid(PAA),known for its environmentally friendly properties as a oxidant and bactericide,is gaining prominence in decontamination and disinfection applications.The primary product of PAA oxidation is acetate that can serve as an electron acceptor(EA)for the biosynthesis of medium-chain fatty acids(MCFAs)via chain elongation(CE)reactions.Hence,PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation,as it could enhance organic matter availability,suppress competing microorganisms and furnish EA by providing acetate.However,such a hypothesis has rarely been proved.Here we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances(EPS)from sludge flocs and disruption of proteinic secondary structures,through inducing highly active free radicals and singlet oxygen.The production of MCFAs increases substantially to 11,265.6 mg COD L^(-1),while the undesired byproducts,specifically long-chain alcohols(LCAs),decrease to 723.5 mg COD L^(-1).Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process,attributed to the up-regulation of functional genes involved in fatty acid biosynthesis pathway.These comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology,advancing our understanding of sustainable resource recovery from sewage sludge.

关 键 词：Sewage sludge Medium-chain fatty acids(MCFAs) Extracellular polymeric substances(EPS) Peracetic acid(PAA) Metabolic activity 

分 类 号：X703[环境科学与工程—环境工程]