Conversion of Gas-Solid Reactions of the Flat Plate Particles with Unchanged Size Using the Shrinking Core Model

Document Type : Research Paper

Authors

Department of Chemical, Oil and Gas Engineering, Shiraz University of Technology, Shiraz, Iran

Abstract

In this paper, a mathematical model is developed to calculate the conversion and the residence time reaction for plug flow and mixed flow in the fluidized reactors filled with flat plate particles using the shrinking core model. In this modeling, the size of the particles is unchanged during the reaction. Also, the reaction rate is controlled by the gas layer resistance, the ash layer resistance, and the reaction resistance as well as the combination of them. It is also assumed that the gas diffuses from the side, whereas the effect of diffusion in the axial direction is neglected. Equations are solved by numerical methods. This paper's innovation is investigating the combination of resistances effect on the conversion of the reaction. The results for a specific time show that when the reaction rate is controlled by each of the resistances individually, the conversion rate is greater. For example when the reaction is controlled by the ash layer resistance versus when the other two resistance regimes control it. Finally, the effect of the combination of different controlling regimes on the conversion and residence time of reaction for plug flow and mixed flow of particles is studied and it is found that the overall results are similar to each other. In addition, the results that the curves for the gas film layer resistance and the chemical reaction resistance, are the same and correspond to each other. Because the equations of the conversion rate are the same.

Keywords