Disinfection for the municipal secondary effluents under microwave induced electrodeless ultraviolet irradiation
ZHANG Yue1, ZHANG Guang-shan1, WANG Peng1,2
1. School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China;
2. State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
The disinfection for the municipal secondary effluents was carried out with a self-made microwave induced electrodeless UV continuous disinfection reactor. The self-made cylindrical electrodeless lamp was used as UV photosource. When the electrodeless lamp was filled with Hg of 10mg and Ar of 666.61Pa inside, the light intensity at wavelength of 253.7nm was the strongest. Then the microwave induced electrodeless UV continuous disinfection process was established. The optimal values of operating parameters were found at a microwave power of 600W and a HRT of 30s, the UV light intensity, the influent flow, the total coliform count and total bacterial count of the effluent were 5.07mW/cm2, 0.072L/s, 0CFU/L and 2CFU/mL, respectively. During the process of microwave induced electrodeless UV disinfection, microwave destroyed the cell wall and cell membrane of bacterial, resulting in the leakage of intracellular substances such as protein and K+. This irreversible destruction could effectively inhibit the photoreactivation in UV disinfection.
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