title: Long-term effects of the ozonation of the sludge recycling stream on excess sludge reduction and biomass activity at full-scale.
abstract: 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.
authors: Politecnico di Milano, DIIAR - Environmental Section, Piazza Leonardo da Vinci 32, 20133 Milano. davide.gardoni@mail.polimi.it
authors: D
authors: D
authors: Gardoni
authors: E
authors: E
authors: Ficara
authors: R
authors: R
authors: Fornarelli
authors: M
authors: M
authors: Parolini
authors: R
authors: R
authors: Canziani
mesh_terms: D018533:Biomass; D019149:Bioreactors; D010126:Ozone; D059027:Recycling; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical; D018508:Water Purification
chemical_list: D012722:Sewage; D014874:Water Pollutants, Chemical; D010126:Ozone