Effect of char gasification reaction order on bounding solutions for char combustion

✍ Scribed by Guillermo Calleja; Adel F. Sarofim; Christos Georgakis

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 848 KB
• Volume: 36
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(81)85046-4

✦ Synopsis

The rate of oxidation and surface temperature of a char particle during combustion is determined by the combined action of reactions of carbon with oxygen and CO2 at the surface and carbon monoxide with O2 in the gas phase. Limiting values for the rates and temperature were determined by Amundson el al. assuming that the C43, and C-CO2 reactions were first order with respect to the gas reactant concentration. Results are presented here for the cases in which the C-O2 reaction is zeroth order and the C4Z02 reaction is both first and zero order to bound the reaction orders found in practice. AUowance for mroth order kinetics is found to have a profound effect on the shape of the bounding solutions for burning rates and temperatures, most notably by showing that diffusion-limited combustion can occur at much lower temperatures than would be predicted using tirst order kinetics.

INTRODLICTION