UVC-based advanced oxidation processes for simultaneous removal of microcontaminants and pathogens from simulated municipal wastewater at pilot plant scale

Abstract

The challenge of providing good quality reclaimed water free from contaminants of emerging concern, even at small concentrations, i.e., microcontaminants (MCs) and pathogens are main hot topics worldwide.

UV-C Peroxymonosulfate Activation for Wastewater Regeneration: Simultaneous Inactivation of Pathogens and Degradation of Contaminants of Emerging Concern

“…The bacterial inactivation profiles observed in all cases obey to a double log-linear kinetic profile explained by the action of the UV-C radiation (a fast k 1 ) and the experimental setup (slower k 2 ) ( Table S3, Figure S2 ), which is similar to previous studies using the same UV-C pilot plant [ 16 ]. k 1 is attributed to the well-known efficiency of UV-C wavelengths to inactivate microorganisms in water.…”

“…Two water matrices were used in this study: (i) Simulated Urban Wastewater (SUWW) and (ii) Actual Urban Wastewater (UWW). SUWW was prepared following a recipe previously reported [ 16 ] as a UWW effluent model to guarantee the reproducibility and comparability of results among the different operational conditions. UWW was freshly collected from the effluent of the secondary treatment (conventional activated sludge) of the urban wastewater treatment plant of “El Bobar”, which is located in Almeria, South East of Spain, and several batches were used along the experimental plan.…”

“…A 80 L UV-C (medium pressure lamp with 254 nm peak wavelengths, 230 W) pilot plant was used in this study in batch mode with a flow-rate of 36 L/min and an illuminated volume (V i ) of 6.21 L. A full description is reported elsewhere [ 16 ]. The UV-C chamber accounts with a UV irradiance detector placed in the inner wall of the lamp chamber to monitor the lamp irradiance (W/m 2 ) emitted at any time.…”

“…Irradiance profiles observed under UV-C irradiation in SUWW and UWW are reported in Figure S1 . This measurement was used to calculate, according to Equation (1), the UV-C accumulative energy per unit of volume Q UV (in kJ/L) [ 16 ]. where Dose is obtained by the UV-C lamp emitted irradiance (W/m 2 ) multiplied by the illumination time fraction (s), A i is the illuminated area (0.34 m 2 ), and V t is the total volume (80 L).…”

Simultaneous Disinfection and Organic Microcontaminant Removal by UVC-LED-Driven Advanced Oxidation Processes

“…Concerning bacterial regrowth, although with 0.147 mM of S 2 O 8 2− the DL of 1 CFU/mL was reached, regrowth occurred after 24 h of the treatment, probably due to the low residual oxidant concentration (below the LOQ). This is in concordance with the results obtained by Sánchez-Montes et al (2020) [28], who reported that S 2 O 2 8− concentrations up to 0.23 mM do not prevent bacterial regrowth, because it has no bactericidal effect by itself. However, with 1.47 mM and 2.94 mM, there was no regrowth below the DL EU of 10 CFU/100 mL, the residual concentrations being 0.92 mM and 1.50 mM, respectively.…”