Nitrate removal to its fate in wetland mesocosm filled with sponge iron:Impact of influent COD/N ratio  

作　　者：Zhihao Si Xinshan Song Xin Cao Yuhui Wang Yifei Wang Yufeng Zhao Xiaoyan Ge Awet Arefe Tesfahunegn 

机构地区：[1]College of Environmental Science and Engineering,State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry,Donghua University,Shanghai 201620,China

出　　处：《Frontiers of Environmental Science & Engineering》2020年第1期77-85,共9页环境科学与工程前沿（英文）

基　　金：This work was supported by the the National Natural Science Foundation of China(Grant Nos.51679041 and 51909034);the Fundamental Research Funds for the Central Universities(Grant Nos.2232019D3-21 and 2232018D3-22);the China Postdoctoral Science Foundation(No.2018M641894);the Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(Nos.CUSF-DH-D-2019079 and CUSF-DH-D-2019080);Shanghai Sailing Program(No.19YF1401900);Shanghai Rising-Star Program(No.19QC1401100).

摘　　要：Sponge iron(s-Fe°)is a porous metal with the potential to be an electron donor for denitrification.This study aims to evaluate the feasibility of using s-Fe as the substrate of wetland mesocosms.Here,wetland mesocosms with the addition of s-Fe"particles(CW-Fc)and a blank control group(CW-CK)were established.The NOj-N reduction property and water quality parameters(pH.DO.and ORP)were examined at three COD/N ratios(0.5.and 10).Results showed that the NO3--N removal efficiencies were significantly increased by 6.6 to 58.9%in the presence of s-Fe NH4+-N was mainly produced by chemical denitrification,and approximately 50% of the NO3--N was reduced to N4+-N,at the COD ratio of 0.An increase of the influent COD/N ratio resulted in lower chemical denitrification and higher bio-dcnitrification.Although chemical denitrification mediated by s-Fe led to an accumulation of NH4+-N at COD/N ratios of 0 and 5.the TIN removal efficiencies increased by 4.5#12.4#.Moreover,the effluent pll,DO.and ORP values showed a significant negative correlation with total Fe and Fe(II)(P<0.01).High-throughput sequencing analysis indicated that Trichococctis(77.2%)was the most abundant microorganism in the CW-Fc mcsocosm,while Thauera,Zoogloea.and Herbaspirillum were the primary denitrifying bacteria.The denitrifiers,Simplicispira,IXxhloronwnas,and Denirratisoma.were the dominant bacteria for CW-CK.This study provides a valuable method and an improved understanding of NOj-N reduction characteristics of s-Fc in a wetland mcsocosm.

关 键 词：Sponge iron WETLAND MESOCOSM Electronic donor DENITRIFICATION COD/N RATIO 

分 类 号：X70[环境科学与工程—环境工程]