Efficient disinfection of combined sewer overflows by ultraviolet/peracetic acid through intracellular oxidation with preserving cell integrity.
Water Res
; 260: 121959, 2024 Aug 15.
Article
en En
| MEDLINE
| ID: mdl-38909420
ABSTRACT
Combined sewer overflows (CSOs) introduce microbial contaminants into the receiving water bodies, thereby posing risks to public health. This study systematically investigated the disinfection performance and mechanisms of the combined process of ultraviolet and peracetic acid (UV/PAA) in CSOs with selecting Escherichia coli (E. coli) as a target microbial contaminant. The UV/PAA process exhibited superior performance in inactivating E. coli in simulated CSOs compared with UV, PAA, and UV/H2O2 processes. Increasing the PAA dosage greatly enhanced the disinfection efficiency, while turbidity and organic matter hindered the inactivation performance. Singlet oxygen (1O2), hydroxyl (â¢OH) and organic radicals (ROâ¢) contributed to the inactivation of E. coli, with â¢OH and RO⢠playing the prominent role. Variations of intracellular reactive oxygen species, malondialdehyde, enzymes activities, DNA contents and biochemical compositions of E. coli cells suggested that UV/PAA primarily caused oxidative damage to intracellular molecules rather than the damage to the lipids of the cell membrane, therefore effectively limited the regrowth of E. coli. Additionally, the UV/PAA process displayed an outstanding performance in disinfecting actual raw CSOs, achieving a 2.90-log inactivation of total bacteria after reaction for 4 min. These results highlighted the practical applicability and effectiveness of the UV/PAA process in the disinfection of CSOs.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ácido Peracético
/
Aguas del Alcantarillado
/
Rayos Ultravioleta
/
Desinfección
/
Escherichia coli
Idioma:
En
Revista:
Water Res
Año:
2024
Tipo del documento:
Article
País de afiliación:
China