This paper presents a full-scale experience of sludge minimization by means of short contact time ozonation in a wastewater treatment plant (WWTP) mainly fed on textile wastewater. The WWTP performance over a 3-year operational data series was analysed and compared with a two-year operation with sludge ozonation. Lab-scale respirometric tests were also performed to characterize biomass activity upstream and downstream of the ozone contact reactor. Results suggest that sludge ozonation: (1) is capable of decreasing excess sludge production by 17%; (2) partially decreases both N removal, by lowering the denitrification capacity, and P removal, by reducing biomass synthesis; (3) increases the decay rate from the typical value of 0.62 d-1 to 1.3 d-1; (4) decreases the heterotrophic growth yield from the typical value of 0.67 to 0.58 gCOD/gCOD.
|Titolo:||Long-term effects of the ozonation of the sludge recycling stream on excess sludge reduction and biomass activity at full-scale|
|Parole Chiave:||Biomass activity; Ozonation; Sludge minimization; Sludge yield|
|Settore Scientifico Disciplinare:||Settore ICAR/03 - Ingegneria Sanitaria-Ambientale|
|Data di pubblicazione:||2011|
|Enti collegati al convegno:||International Water Association|
|Digital Object Identifier (DOI):||10.2166/wst.2011.456|
|Appare nelle tipologie:||01 - Articolo su periodico|