title: Coupling scales for modelling heavy metal vaporization from municipal solid waste incineration in a fluid bed by CFD.
abstract: Municipal Solid Waste Incineration (MSWI) in fluidized bed is a very interesting technology mainly due to high combustion efficiency, great flexibility for treating several types of waste fuels and reduction in pollutants emitted with the flue gas. However, there is a great concern with respect to the fate of heavy metals (HM) contained in MSW and their environmental impact. In this study, a coupled two-scale CFD model was developed for MSWI in a bubbling fluidized bed. It presents an original scheme that combines a single particle model and a global fluidized bed model in order to represent the HM vaporization during MSW combustion. Two of the most representative HM (Cd and Pb) with bed temperatures ranging between 923 and 1073K have been considered. This new approach uses ANSYS FLUENT 14.0 as the modelling platform for the simulations along with a complete set of self-developed user-defined functions (UDFs). The simulation results are compared to the experimental data obtained previously by the research group in a lab-scale fluid bed incinerator. The comparison indicates that the proposed CFD model predicts well the evolution of the HM release for the bed temperatures analyzed. It shows that both bed temperature and bed dynamics have influence on the HM vaporization rate. It can be concluded that CFD is a rigorous tool that provides valuable information about HM vaporization and that the original two-scale simulation scheme adopted allows to better represent the actual particle behavior in a fluid bed incinerator.
authors.affiliation: Institute for Research and Development in Process Engineering, Biotechnology and Alternative Energies (PROBIEN, CONICET - UNCo), 1400 Buenos Aires St., 8300 Neuquén, Argentina. Electronic address: jose.soria@probien.gob.ar.
authors.forename: José
authors.initials: J
authors.lastname: Soria
authors.affiliation: Processes, Materials and Solar Energy Laboratory (PROMES-CNRS, UPR 8521), 7 Four Solaire Street, Odeillo, 66120 Font-Romeu, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Gauthier
authors.affiliation: Processes, Materials and Solar Energy Laboratory (PROMES-CNRS, UPR 8521), 7 Four Solaire Street, Odeillo, 66120 Font-Romeu, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Flamant
authors.affiliation: Chemical Engineering Institute, National University of San Juan, 1109 Libertador (O) Avenue, 5400 San Juan, Argentina.
authors.forename: Rosa
authors.initials: R
authors.lastname: Rodriguez
authors.affiliation: Institute for Research and Development in Process Engineering, Biotechnology and Alternative Energies (PROBIEN, CONICET - UNCo), 1400 Buenos Aires St., 8300 Neuquén, Argentina.
authors.forename: Germán
authors.initials: G
authors.lastname: Mazza
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D019149:Bioreactors; D003198:Computer Simulation; D004867:Equipment Design; D005740:Gases; D017745:Incineration; D007700:Kinetics; D019216:Metals, Heavy / Q000737:chemistry*; D010316:Particle Size; D012037:Refuse Disposal / Q000379:methods*; D015203:Reproducibility of Results; D062611:Solid Waste; D013696:Temperature; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D005740:Gases; D019216:Metals, Heavy; D062611:Solid Waste
keywords: Computational fluid dynamic; Fluidized bed; Heavy metal vaporization; Two-scale model; Waste incineration