Application of Ultraviolet LED for Sterilizing in Water Purifier

Thien Duc Tran1, , Minh Tan Le1, Thu Thuy Tran2, Duy Dat Vu1, Xuan Truong Cao1, Dinh Huu Duc Nguyen1
1 Truong Dai hoc Bach khoa Ha Noi - So 1 Dai Co Viet, Hai Ba Trung, Ha Noi, Viet Nam
2 Truong PTTH chuyen Ba Noi - Amsterdam, So 1 Hoang Minh Giam, Cau Giay, Ha Noi, Viet Nam

Main Article Content

Abstract

UVC LED with a wavelength of 275 nm and emission power of 4.5 mW was applied to sterilize in water purifier. The ability to sterilization of water purifier was studied on E.coli bacteria. E.coli bacteria were added into the water sample with a concentration of 6800 CFU/100 mL before irradiating. The irradiating time is set up at different values of 15 s; 30 s; 60 s. The result shows that, the bacteria concentration rapidly decreases with an increase of irradiating time. With the duration of 30 s, the bacteria concentration after irradiating is about 3 CFU/100 ml, corresponding to the sterilization ratio of 99,995%. The UVC LED system was also designed to optimize the irradiating area and time, thereby the sterilization efficiency will be enhanced.

Article Details

References

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