Comparison of UVC and Solar-based Processes for the Simultaneous Removal of Microcontaminants and Microorganism from Urban Wastewater Effluents I.

Currently, the presence of microcontaminats (MCs) and pathogens in secondary municipal wastewater treatment plant effluents entails a challenge to be addressed before water discharge or reuse. In this work UVC (UVC/S2O82-, UVC/H2O2) and solar-based processes (solar/S2O82- and solar/H2O2) are proposed as tertiary treatments for the simultaneous removal of both, MCs and pathogens, comparing their efficiency aiming to find the most suitable solution. The microorganisms studied were Escherichia coli, Enterococcus faecalis and Salmonella enteritidis in a concentration of 103 CFU mL-1 each and a mixture of 6 MCs (acetaminophen, caffeine, carbamazepine, trimethoprim, sulfamethoxazole and diclofenac) each at 100 μg L-1 of initial concentration, using simulated wastewater treatment plant effluent as water matrix. The concentrations of oxidants studied were 25 and 50 mg L-1 of each, respectively. Results revealed that UVC/H2O2 at 25 mg L-1 presented the most satisfactory solution considering treatment time and addition of reagents for complete inactivation of target pathogens and 80% removal of the sum of MCs.