A full-scale plug-flow reactor for biological sludge ozonation.
The reduction of biological excess sludge production using ozone is a well-known technology and is applied in several full-scale plants around the world. Nevertheless, optimisation of the process is not yet adequately documented in the literature. Operational parameters are usually chosen by assuming a direct proportionality between ozone dose and excess sludge reduction. This paper investigates the role of ozone concentration on process efficiency and demonstrates the (non-linear) inverse relationship between ozone dose and specific particulate chemical oxygen demand solubilisation in plug-flow contact reactors. The influence of total suspended solids concentration is also studied and described. No short-term lethal effects on heterotrophic biomass have been observed.
Politecnico di Milano, DICA - Environmental Section, Piazza Leonardo da Vinci, 32. 20133 Milano, Italy E-mail: roberto.canziani@polimi.it.
Davide
D
Gardoni
Politecnico di Milano, DICA - Environmental Section, Piazza Leonardo da Vinci, 32. 20133 Milano, Italy E-mail: roberto.canziani@polimi.it.
Elena
E
Ficara
Politecnico di Milano, DICA - Environmental Section, Piazza Leonardo da Vinci, 32. 20133 Milano, Italy E-mail: roberto.canziani@polimi.it.
Pompilio
P
Vergine
Politecnico di Milano, DICA - Environmental Section, Piazza Leonardo da Vinci, 32. 20133 Milano, Italy E-mail: roberto.canziani@polimi.it.
Roberto
R
Canziani
D018533:Biomass; D019149:Bioreactors; D010126:Ozone; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*
D012722:Sewage; D010126:Ozone