Abstract
We developed a multizonal thermodynamic equilibrium calculation model to estimate the fate of ash-forming elements in solid waste incineration plants. This model divides processes of an incineration plant into three steps, (1) incineration of combustible waste and reactions of ash-forming elements, (2) high-temperature reactions of flue gas and additives in a combustion chamber, and (3) flue gas cooling/cleaning processes. In each step, equilibrium composition was calculated using a commercial thermodynamic equilibrium calculation software (ChemSheet, GTT-technologies), and by multiplying the conversion efficiency, the product composition of the step was estimated and that was used in the next steps as their inlet compositions. In this study, we modified the model to estimate the fate of heavy metal in a lab-scale RDF incineration plant and 2 industrial waste incineration plants, to evaluate the accuracy of the calculation. The relative difference between the calculated and measured elemental distributions among the incineration residues were within 20 % for Cd, Cr, Mn, Se, Pb, Ni, V, Be, and B, and 25 % for Sn and As, indicating that this calculation can be used in the estimation of fate of 12 inorganic substances regulated by PRTR (pollutant release and transfer register).
