Single-Particle Characterization of Municipal Solid Waste (MSW) Ash Particles Using Low-Z Particle Electron Probe X-ray Microanalysis

초록

Many countries are currently using incineration to reduce municipal solid waste (MSW) volume and the treatment of MSW ash in an environmentally benign way is an important issue worldwide. And thus thorough knowledge of chemical composition of MSW ash is required for its effective and safe management. In general, the main constituents of MSW ash, that is the inorganic mixture of glass-like and crystalline minerals, are SiO2, Al2O3, CaO, Fe2O3, Na2O, K2O, TiO2, CaCO3, NaCl, CaSO4, MgO, ZnO, P2O5, and PbO and so on (Kirby & Rimstldt, 1993). However, the comprehensive characterization of the diverse chemical compositions and multiple-phase of MSW ash can be achieved by the combined application of several different bulk analytical methods, such as inductively coupled plasma-atomic emission spectroscopy (ICP-AES), neutron activation, titration, and powder X-ray diffraction (XRD). A single particle analytical technique, called low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA), employing an ultra-thin window X-ray detector and enabling the quantitative determination of even low-Z elements such as C, N, and O, was applied to characterize MSW fly- and bottom-ash particle samples from two incinerators in Korea. The low-Z particle EPMA provided detailed information on chemical compositions of the MSW ash particles and it was demonstrated that this technique has a powerful advantage over conventional analytical techniques in the point that chemical speciation of crystalline and glass-like ash particles can simultaneously be performed.