Limestone addition changed the Cl deposition. Combustion
of 32PC68RDF without limestone produced negligible
Cl concentrations on wind-side and 50- away, but as much
as 24.6 wt.% Cl was found on lee-side. In contrast, chlorine
deposition was weak to lee-side and strong to the other
positions during limestone addition (Fig. 9). Cl/(K+Na) was
0.96 on the lee-side without limestone indicating that
chlorine deposited almost entirely via condensation of alkali
chlorine vapors. In contrast, impaction in coarser limestone
particles was probably the dominating Cl deposition
mechanism during limestone addition: Ca/S molar ratio
was 2.45 on wind-side indicating that Ca was not solely
bound to S in CaSO4. Since Cl/(K+Na) was 1.22, the
presence of CaCl2 was also possible (together with NaCl and KCl). The same trend prevailed with the other coal/RDF
blends during limestone addition: highest chlorine concentration
was on wind-side and 50- up with Cl/(K+Na) and
Ca/S molar ratios >1, while lower chlorine concentration
was found in the lee-side.