Inactivation Mechanisms of Escherichia Coli in Drinking Water Using Reactive Species Generated from a Surface Discharge  

作　　者：LI Jie SHANG Kefeng WANG Tiecheng LU Na WANG Tianwei WU Yan 

机构地区：[1]Institute of Electrostatics and Special Power, Dalian University of Technology, Dalian 116024, China

出　　处：《高电压技术》2013年第9期2119-2124,共6页High Voltage Engineering

基　　金：Project supported by Ministry of Science and Technology of China （2008AA06Z308）, National Natural Science Foundation of China （40901150）, Joint Fund of the National Natural Science Foundation of China （U0970166）, Doctoral Program Foundation of Institutions of Higher Education of China （20070141004）, Program for Liaoning Excel- lent Talents in University of China （2009R09）, Fundamental Research Fund for the Central Universities （DUT12RC（3）12）.

摘　　要：Bacterial and chemical contaminations of drinking water imperil the health of people.A reactive species injection method is presented for sterilizing drinking water.To produce reactive species,a gas phase surface discharge reactor(SDR)is designed:a spiral stainless steel wire attached on the inside wall of a quartz glass tube is used as the high voltage electrode,and the drinking water is the ground electrode.The performance and mechanisms of the method in inactivating of Escherichia coli(E.coli)are analyzed.Experimental results show that 500 mL E.coli-contaminated drinking water(108CFU/mL)is completely sterilized within 4 min.Based on the scanning electron microscope(SEM)analysis,there were plasma-induced cell structure damages of the E.coli in the sterilized water,and the damage resulted in the leakage of protein,which was proved by chemical analyses.Meanwhile,the heating effect concomitantly generated by discharge plasma does not influence E.coli inactivation,and the contribution of direct ultraviolet(UV)irradiation could be neglected too.The ozone generated by SDR and the hydroxyl radicals(·OH)subsequently generated in drinking water play the decisive roles in E.coli inactivation because these reactive species cause the cell rupture.Bacterial and chemical contaminations of drinking water imperil the health of people. A reactive species injection method is pre- sented for sterilizing drinking water. To produce reactive species, a gas phase surface discharge reactor （SDR） is designed： a spiral stainless steel wire attached on the inside wall of a quartz glass tube is used as the high voltage electrode, and the drinking water is the ground elec- trode. The performance and mechanisms of the method in inactivating of Escherichia coli （E. coli） are analyzed. Experimental results show that 500 mL E. coli-contaminated drinking water （108 CFU/mL） is completely sterilized within 4 min. Based on the scanning electron mi- croscope （SEM） analysis, there were plasma-induced cell structure damages of the E. coli in the sterilized water, and the damage resulted in the leakage of protein, which was proved by chemical analyses. Meanwhile, the heating effect concomitantly generated by discharge plasma does not influence E. coli inactivation, and the contribution of direct ultraviolet （UV） irradiation could be neglected too. The ozone generat- ed by SDR and the hydroxyl radicals （.OH） subsequently generated in drinking water play the decisive roles in E. coli inactivation because these reactive species cause the cell rupture.

关 键 词：饮用水消毒 大肠杆菌 表面放电型 活性物种 机制 灭活 放电等离子体 扫描电子显微镜 

分 类 号：X703[环境科学与工程—环境工程] TU991.25[建筑科学—市政工程]