Historical Background and Technology Development

From Handbook of Environmental Engineering, Volume 4 Advanced Physicochemical Treatment Processes Edited by L. K. Wang, Y.-T. Hung, and N. K. Shammas The Humana Press Inc., Totowa, NJ 

However, to effectively control the waterborne diseases, a combination of various chemical and physical processes is often adopted in typical water and wastewater disinfection processes. 

UV radiation has been used widely in water and air disinfection, as well as organic pollutant oxidation. The germicidal properties of UV radiation were first discovered in 1801. In 1877, the bactericidal effect of sun light (contaiiung UV fight with a wavelength more than 290 nm) was reported by Downes and Blunt. In 1901, the first mercury vapor lamp was commercialized as a method of UV generation (1). Nine years later, the 

UV disinfectant is not able to stay in the water for a long period, which acts as a prevention for the pathogens in the distribution network system. 

It is not effective for disinfection of G. lamblia cysts and Cryptosporidiumparvum oocysts. 

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