Dynamics of gas phase and solid phase reactions in fixed bed reactors

✍ Scribed by Milind S. Kulkarni; Milorad P. Dudukovic'

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 443 KB
• Volume: 51
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(96)00201-1

✦ Synopsis

Volumetric thermal capacity of solids is higher than that of gases by three orders of magnitude. We show that this leads to a dynamic response of a fixed bed reactor involving a solid phase reaction which is sluggish compared to that involving a gas pha~ reaction of the same kinetic and thermodynamic parameters. In the dynamic regime where the inlet gas temperature is lower than the initial bed temp~ature, fixed bed reactors exhibit the wrong way behavior. We show that in this regime, the transient maximum temperature rise and the steepness of the t¢mperature front are affeeted by the phase in which reaction occurs, by the inlet gas tamperature and by the volumetric heat transfer rate. The maximum temperature rise in the bed is lower for the solid phase reaction and dcereases with a deerease in the volumetric heat transfer coefficient.

These and other n¢w findings are obtained by our newly developed robust, completely implicit, spatially and tamporally adaptive numerical algorithm which can capture stesp moving fronts in fixed bed reactors.