Advanced treatment for municipal wastewater reuse in agriculture. UV disinfection: parasite removal and by-product formation Original Research Article

This paper reports the experimental results of a pilot-scale (100 m3/h) investigation, carried out at the West Bari (S. Italy) municipal wastewater treatment plant, focused on parasite removal and disinfection by-product (DBP) formation during the UV disinfection of clarified (CL) and clarified-filtered (F) secondary municipal effluents at doses necessary for achieving the Italian microbial limit for unrestricted reuse of wastewater in agriculture (2 CFU/100ml of total coliforms). The investigation demonstrated that parasites like Giardia lamblia cysts and Cryptosporidium parvum oocysts were both significantly affected by UV radiation and that potential UV-promoted formation of DBPs (nitro-phenols and N-nitroso-amines) did not occur according to GC/MS and LC/MS analytical evidences. O&M costs ranged from 17.5 up to 35/1000 m3 for effluent F and CL respectively.