Affiliations: State Key Laboratory of Coal Combustion, Huazhong
University of Science and Technology, Wuhan 430074, China | Institut de Science et de Genie des Materiaux et
Procedes (CNRS-IMP), BP 5Odeillo, 66125 Font-Romeu Cedex, France
Abstract: Incineration experiments with MSW, which had been impregnated with
heavy metals, were presented toobtain information on the volatilization
behavior of the elements cadmium (Cd), lead (Pb), and zinc (Zn) underdifferent
conditions. Experiments were carried out in a bubbling fluid bed system
connected to a customizedinductively coupled plasma optical emission
spectroscopy (ICP-OES) for analyzing metals in the flue gas. The
resultsindicated that the combustion temperature, the gas atmosphere, and the
chlorine content in the flue gas could affectthe volatilization behavior of
heavy metals. In the fluidized bed combustion, a large surface area was
provided by thebed sand particles, and they may act as absorbents for the
gaseous ash-forming compound. Comparer with themetals Cd and Pb, the
vaporization of Zn was Iow. The formation of stable compounds such as
ZnO˙Al_2O_3 couldgreatly decrease the
metals volatilization. The presence of chlorine would enhance the
volatilization of heavy metalsby increasing the formation of metal chlorides.
However, when the oxygen content was high, the chlorinatingreaction was
kinetically hindered, which heavy metals release would be delayed.
Keywords: municipal solid waste, incineration, heavy metal emission, fluidized bed
