Advanced water treatment technology for oxidation and disinfection by ultraviolet irradiation

Advanced oxidation processes (AOP) were expected to be powerful water treatment techniques. An aim is to develop an AOP that mainly uses ultraviolet irradiation for treatment of the refractory organics and the disinfecting of pathogenic microbes. It is presumed that the generation of hydroxyl radical is the key factor for the treatment performance of AOP. In this research, a method to quantify the hydroxyl radical generation was first examined, then the obvious generation of hydroxyl radical was observed in a photocatalyst/ultraviolet irradiation. Secondly, a method to detect biological activity of the pathogenic protozoan Cryptosporidium, that caused serious outbreaks in the worldwide was studied. It was revealed that Cryptosporidium could be inactivated by the ultraviolet irradiation.