Mass and trace element size distributions of aerosols emitted by a hospital refuse incinerator

Abstract

Mass and elemental size distributions of hospital refuse incineration aerosols were measured in the aerodynamic particle size range 0.02–17 μm with an in-stack compressible flow, low pressure impactor. Oil was used as a supplementary fuel in the refuse combustion process and flue gases were cleaned with a cyclone. Mass size distributions were bimodal. The geometric aerodynamic mean diameter of the fine mode varied between 0.1 and 0.2 μm and the corresponding coarse mode mean between 6 and 10 μm. Mg, Al, Cl, Ti and Fe were found only in coarse mode particles. Elemental size distributions of Na, K, Zn, Cd, Pb and S were bimodal. Over 90% of the particle phase of S, 20–80% of Zn, 62–77% of Cd and 7–74% of Pb, respectively, were found in the fine mode particles. This existence of the fine mode peak in the size distributions of Na, K, Zn, Cd, Pb and S indicates that at least part of these elements vaporizes during the refuse incineration process.