4.1.2. HCl emissions
In most of the experiments, HCl emissions increased with
chlorine concentration (Fig. 4). However, fuel-Cl conversion to HCl was highest with the coal-rich blends (80% coal/20%
RDF) (Table 3). Limestone can be used to capture HCl by
reactions (1)–(3) [19]. SO2 also reacts with limestone. Experimental studies [20] have
shown how the conversion of CaO to CaCl2 may be high when
HCl is present without SO2, but approaches zero when SO2 is added to the gas. The results from 100 kW CFB (Fig. 5)
indicated clearly that SO2 capture dominated over HCl capture
by limestone: in contrast to SO2 concentration, HCl concentration
decreased only slightly after the start of limestone
dosage (Table 4).