Improved wastewater ultraviolet disinfection by ultrasonic pre-treatment
The objective of this research is to explore fundamental characteristics of how particles and bacteria in wastewater respond to ultrasonic(US), with an aim to improve the ultraviolet(UV)disinfection by using US as a pre-treatment method and find mechanism of synergistic disinfection. Experiments have been done by use of two frequencies (21.51 kHz and 83.03kHz) US joint UV to disinfect the effluent of WWTPs. The results show that: Sonication has two effects on suspended solids or bacteria. First is bacterial declumping which breaks up bacterial clumps into a greater number of individuals, and second is bacterial killing. Ultrasonic has the effect on disinfecting bacteria, while the disinfect efficiency is not so high. US can improve the particles size distribution and raise the value of CODCr; enhance the UV disinfection efficiency by working as an pre-treatment method. In our lab-scale tests, 30 s of UV treatment alone were required to reduce the number of fecal coliforms by 2.8 log units. When applied in combination, 5 min of ultrasonic followed by only 15 s of UV irradiation almost has the same result and energy consumption is lower. Furthermore, the phenomenon of photoreactivation was under control. The critical control factors of US&UV synergistic disinfection is UV irradiation time, US energy density and frequency.
Ultrasonic ultraviolet synergistic disinfection wastewater
Jin Xin Li Zifu Li Yongli Xu Chao
School of civil & environmental engineering USTB ,100083 , Beijing
国际会议
2009 Beijing International Environmental Technology Conference(2009北京国际环境技术会议暨第五届“中、德、波环境技术研讨会)
北京
英文
498-505
2009-10-16（万方平台首次上网日期，不代表论文的发表时间）