CHEMISTRY OF THE FLY ASH AND ITS RESPIRABLE –SIZE FRACTION (<10ΜM) FROM THE POWER UNITS OF AGIOS DIMITRIOS THERMAL POWER PLANT, NORTHERN GREECE

3rd International Scientific Conference - SGEM2003, www.sgem.org, SGEM2003 Conference Proceedings/ ISBN: 954-918181-2, June 9-13, 2003, 335- 342pp

ABSTRACT

Major and trace element concentrations were measured in representative fly
ash samples from four Power Units of Agios Dimitrios Thermal Power Plant,
Northern Greece. Major and trace element concentrations were also measured in
the respirable-size fly ash fraction (<10μm) of the same samples, separated from
the bulk fly ash by laboratory treatment. The respirable-size fraction, compared to
the bulk fly ash was found richer in CaO and poorer in all other major oxides
(SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, Na2O, K2O, P2O5 and SO3). Concerning
the environmental aspects of the fly ash emissions, the ratios of an element
concentration in the bulk fly ash to that of the respirable-size fly ash fraction were
determined. Thirty-six elements (V, Cr, Co, Ni, Zn, Ga, Ge, As, Rb, Y, Zr, Nb,
Mo, Sb, Cs, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W,
Tl, Pb, Th, U) show 1.6 to more than 6.3 times lower concentrations in the
respirable-size fraction, while only three elements (Sr, Ba, Cu) show more or less
the same concentrations as the bulk fly ash.