Kinetic analysis of Legionella inactivation using ozone in wastewater.
Legionella inactivation using ozone was studied in wastewater using kinetic analysis and modeling. The experimental results indicate that the relationship between the ozone concentration, germ concentration, and chemical oxygen demand (COD) can be used to predict variations in germ and COD concentrations. The ozone reaction with COD and inactivation of Legionella occurred simultaneously, but the reaction with COD likely occurred at a higher rate than the inactivation, as COD is more easily oxidized by ozone than Legionella. Higher initial COD concentrations resulted in a lower inactivation rate and higher lnN/N0. Higher temperature led to a higher inactivation efficiency. The relationship of the initial O3concentration and Legionella inactivation rate was not linear, and thus, the Ct value required for a 99.99% reduction was not constant. The initial O3concentration was more important than the contact time, and a reduction of the initial O3concentration could not be compensated by increasing the contact time. The Ct values were compared over a narrow range of initial concentrations; the Ct values could only be contrasted when the initial O3concentrations were very similar. A higher initial O3concentration led to a higher inflection point value for the lnN/N0vs C0t curve. Energy consumption using a plasma corona was lower than when using boron-doped diamond electrodes.
School of Environmental Science and Engineering, Zhejiang Gongshang University, 18 Xuezheng Street, Xiasha Gaojiaoyuan District, Hangzhou, Zhejiang, 310018, China. Electronic address: lijun681116@163.com.
Jun
J
Li
College of Engineering, Nanjing Agricultural University, 40 Dianjiangtai Road, Pukou District, Nanjing, Jiangsu, 210031, China.
Kunquan
K
Li
Department of Road Traffic and Engineering Planning, Zhejiang Urban & Rural Planning Design Institute, 238 Baochu Road, Xihu District, Hangzhou, Zhejiang, 310007, China.
Yan
Y
Zhou
Department of Management and Information Technology, Nantong Shipping College, 185 Tongsheng Road, Nantong, Jiangsu, 226010, China.
Xuebin
X
Li
School of Environmental Science and Engineering, Huazhong University of Science & Technology, 1037 Luoyu Road, Wuhan, Hubei, 430074, China.
Tao
T
Tao
D057919:Biological Oxygen Demand Analysis; D001895:Boron; D018130:Diamond; D004203:Disinfection / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D007700:Kinetics; D007875:Legionella / Q000254:growth & development*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D013696:Temperature; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
D001895:Boron; D018130:Diamond; D010126:Ozone; D062065:Wastewater
Activation energy; Energy consumption; Indigo; Tail phenomena