SULFUR-DIOXIDE REACTIVITY OF CARBONATE ROCKS .3. INFLUENCE OF POROSITY AND PURITY OF SORBENTS

Comparative data are reported on the sulphur dioxide reactivity of 12 Italian limestones, which are possible sorbents for large-scale fluidized-bed combustors. Physical characterization of the limestones was carried out using different techniques such as X-ray diffraction, i. r. spectrophotometry, N//2 adsorption and mercury porosimetry. SO//2 reactivity, as determined using a fixed bed quartz reactor (T equals 850 degree C,SO//2 equals 6200 ppm) ranged from 17 to 57 wt%CaO conversion. It has been proposed that the performance of desulphurization sorbents, through the dependence on the physical and chemical characteristics, can be forecast by a simple linear semi-empirical equation.