文献类型：期刊文献

英文题名：Low-rate ferrate dosing damages the microbial biofilm structure through humic substances destruction and facilitates the sewer biofilm control

作者：Yan, Xiaofang[1];Sun, Jing[1,2];Wang, Yizhen[1];Zhang, Zisha[1];Zhang, Chuning[1];Li, Wei[2,3];Xu, Juan[4];Dai, Xiaohu[1,2];Ni, Bing-Jie[5]

机构：[1]Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resource Reuse, Key Lab Yangtze River Water Environm, Shanghai 200092, Peoples R China;[2]Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China;[3]East China Univ Sci & Technol, Natl Engn Res Ctr Ind Wastewater Detoxicat & Resou, Shanghai, Peoples R China;[4]East China Normal Univ, Sch Ecol & Environm Sci, Shanghai 200241, Peoples R China;[5]Univ Technol Sydney UTS, Ctr Technol Water & Wastewater CTWW, Sch Civil & Environm Engn, Sydney, NSW 2007, Australia

年份：2023

卷号：235

外文期刊名：WATER RESEARCH

收录：;EI(收录号：20231113738420);WOS:【SCI-EXPANDED(收录号:WOS:000951703300001)】；

基金：This work was financially supported by the National Natural Science Foundations of China (Grants 51978492, 521310025 and 52270092) , Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse Foundation (2020EPC02) , the National Key Research and Development of China (2020YFD1100104) .

语种：英文

外文关键词：Biofilm structure; Ferrate; Extracellular polymeric substances; Humic substances; Biofilm control; Sewer management

摘要：The microbial activities in sewer biofilms are recognized as a major reason for sewer pipe corrosion, malodor, and greenhouse gas emissions. However, conventional methods to control sewer biofilm activities were based on the inhibitory or biocidal effect of chemicals and often required long exposure time or high dosing rates due to the protection of sewer biofilm structure. Therefore, this study attempt to use ferrate (Fe(VI)), a green and high-valent iron, at low dosing rates to damage the sewer biofilm structure so as to enhance sewer biofilm control efficiency. The results showed the biofilm structure started to crush when the Fe(VI) dosage was 15 mg Fe(VI)/L and the damage enhanced with the increasing dosage. The determination of extracellular polymeric substances (EPS) showed that Fe(VI) treatment at 15-45 mgFe/L mainly decreased the content of humic substances (HS) in biofilm EPS. This is because the functional groups, such as C-O,-OH, and C=O, which held the large molecular structure of HS, were the primary target of Fe(VI) treatment as suggested by 2D-Fourier Transform Infrared spectra. As a result, the coiled chain of EPS maintained by HS was turned to extended and dispersed and consequently led to a loosed biofilm structure. The XDLVO analysis suggested that both the microbial interaction energy barrier and secondary energy minimum were increased after Fe(VI) treatment, suggesting that the treated biofilm was less likely to aggregate and easier to be removed by the shear stress caused by high wastewater flow. Moreover, combined Fe(VI) and free nitrous acid (FNA) dosing experiments showed for achieving 90% inacti-vation, the FNA dosing rate could be reduced by 90% with the exposure time decreasing by 75% at a low Fe(VI) dosing rate and the total cost was substantially decreased. These results suggested that applying low-rate Fe(VI) dosing for sewer biofilm structure destruction is expected to be an economical way to facilitate sewer biofilm control.