Tailing propensity in the ultraviolet disinfection of trickling filter and activated sludge wastewater treatment processes.
Water Sci Technol
; 76(3-4): 623-632, 2017 Jul.
Article
em En
| MEDLINE
| ID: mdl-28759444
ABSTRACT
In this paper, the effect of suspended flocs on the tailing of ultraviolet (UV) disinfection kinetics of secondary effluents was examined. To achieve this goal, final effluents produced in two processes for treating wastewater; namely, a trickling filter system and an activated sludge system, were collected and their UV disinfection were compared. Tailing of the UV dose response curve was controlled by the fraction of flocs that are both culturable and UV-resistant, referred to as the 'tailing propensity'. Using this parameter, the contribution of various floc size fractions in reducing the UV disinfection efficiency of wastewater samples was quantified. Activated sludge flocs larger than 125 µm exhibited as much as 35 times greater tailing propensity than smaller flocs in the range of 20-25 µm. Within a fixed size range, the tailing propensity of flocs generated in the trickling filter system was 3 to 8 times higher than that of activated sludge flocs, and this difference increased with the floc size. A mathematical model was developed to predict the UV disinfection of secondary effluents from suspended particle size distribution data. The model showed good agreement with experimental results.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Esgotos
/
Raios Ultravioleta
/
Águas Residuárias
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Water Sci Technol
Assunto da revista:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article