title: Wet oxidation of sewage sludge: full-scale experience and process modeling.
abstract: Nowadays, sewage sludge management represents one of the most important issues in wastewater treatment. Within the European project "ROUTES," wet oxidation (WO) was proposed for sludge minimization. Four different types of sludge were treated in an industrial WO plant: (1) municipal primary sludge (chemical oxygen demand COD: 73.0 g/L; volatile suspended solid VSS: 44.1 g/L); (2) secondary sludge from an industrial wastewater treatment plant (WWTP) without primary sedimentation (COD: 71.8 g/L; VSS: 34.2 g/L); (3) secondary sludge from a mixed municipal and industrial WWTP without primary sedimentation (COD: 61.9 g/L; VSS: 38.7 g/L); and (4) mixed primary (70%) and secondary (30%) municipal sludge (COD: 81.2 g/L; VSS: 40.6 g/L). The effect of process parameters (temperature, reaction time, oxygen dosage) on WO performance was investigated. Depending on operating conditions, VSS and COD removal efficiency varied in the range 80-97% and 43-71%, respectively. A correlation between process efficiency and the initial VSS/TSS (total suspended solids) ratio was highlighted. Furthermore, a mathematical model of WO process for simulating VSS and COD profiles was developed.
authors.affiliation: Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, I-25123, Brescia, Italy, giorgio.bertanza@unibs.it.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Bertanza
authors.forename: Raniero
authors.initials: R
authors.lastname: Galessi
authors.forename: Laura
authors.initials: L
authors.lastname: Menoni
authors.forename: Roberta
authors.initials: R
authors.lastname: Salvetti
authors.forename: Edoardo
authors.initials: E
authors.lastname: Slavik
authors.forename: Sabrina
authors.initials: S
authors.lastname: Zanaboni
mesh_terms: D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D007700:Kinetics; D008962:Models, Theoretical; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D010100:Oxygen; D012722:Sewage; D062065:Wastewater