Record Display for the EPA National Library Catalog


Main Title Sintering and Sulfation of Calcium Silicate: Calcium Aluminate.
Author Borgwardt, R. H. ; Rochelle, G. T. ;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Air and Energy Engineering Research Lab. ;Texas Univ. at Austin. Dept. of Chemical Engineering.
Publisher c1990
Year Published 1990
Report Number EPA/600/J-90/392;
Stock Number PB91-171488
Additional Subjects Sintering ; Calcium silicates ; Aluminates ; Sulfation ; Chemical reactivity ; Sulfur dioxide ; Water ; Calcium sulfates ; Temperature effects ; Reaction kinetics ; Surface properties ; Air pollution control ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB91-171488 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 8p
The effect of sintering on the reactivity of solids at high temperature was studied. The nature of the interaction was studied with calcium silicate-aluminate reacting with SO2 between 665 and 800 C. The kinetics of the sintering and sulfation processes were measured independently in terms of the common variables, temperature and specific surface area. Surface reduction parameters were evaluated by the German-Munir sinter model, modified to account for a strong catalytic effect of H2O vapor. Sulfation parameters were determined from a series of conversion vs. time measurements at various temperatures using calcined solids of known surface area. These show product layer diffusion through CaSO4 to be the probable controlling process above 670 C and diffusion through a mixture of CaSO3 and CaSO4 controlling below that temperature. Like sintering, sulfation was enhanced by the presence of H2O in the feed gas. With 7% H2O vapor, the enhancement factor for sulfation was 1.5 at 665 C and estimated to be 5.0 at higher temperatures where only CaSO4 is formed. A combined sinter/sulfation model, based on the parameters evaluated for the independent processes, is compared to sulfation rates measured for the uncalcined solid when sintering is occurring simultaneously.