Mechanistic insight into the biofilm formation and process performance of a passive aeration ditch(PAD)for decentralized wastewater treatment  

作　　者：Jibin Li Jinxing Ma Li Sun Xin Liu Huaiyu Liao Di He 

机构地区：[1]Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education,Institute of Environmental and Ecological Engineering,Guangdong University of Technology,Guangzhou,510006,China [2]Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),Guangzhou,511458,China [3]School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China

出　　处：《Frontiers of Environmental Science & Engineering》2022年第7期35-46,共12页环境科学与工程前沿（英文）

基　　金：supported by Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(China)(No.GML2019ZD0403);the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(China)(No.2019ZT08L213);the China Postdoctoral Science Foundation(No.2020M672540);the joint Fund Project of Guangdong Basic and Applied Basic Research Fund(China)(No.2020A1515110309).

摘　　要：Decentralized wastewater containing elevated salinity is an emerging threat to the local environment and sanitation in remote coastal communities.Regarding the cost and treatment efficiencies,we propose a passive aeration ditch(PAD)using non-woven polyester fabric as a feasible bubbleless aerator and biofilm carrier for wastewater treatment.Consideration has been first given to PAD’s efficacy in treating saline decentralized wastewater,and then to the impact of chemical oxygen demand-to-nitrogen(C/N)ratio and salinity on biofilm formation.A multispecies model incorporating the salinity effect has been developed to depict the system performance and predict the microbial community.Results showed that the PAD system had great capacity for pollutants removal.The biofilm thickness increased at a higher C/N ratio because of the boost of aerobic heterotrophs and denitrifying bacteria,which consequently improved the COD and total nitrogen removal.However,this led to the deterioration of ammonia removal.Moreover,while a higher salinity benefited the biofilm growth,the contaminant removal efficiencies decreased because the salinity inhibited the activity of aerobic heterotrophs and reduced the abundance of nitrifying bacteria inside the biofilm.Based on the model simulation,feed water with salinity below 2%and C/N ratio in a range of 1 to 3 forms a biofilm that can reach relatively high organic matter and ammonia removal.These findings not only show the feasibility of PAD in treatment of saline decentralized wastewater,but also offer a systematic strategy to predict and optimize the process performance.

关 键 词：Decentralized wastewater Passive aeration ditch Biofilm formation C/N ratio SALINITY Model simulation 

分 类 号：X703[环境科学与工程—环境工程]