Application of CFD to improve calculated process of methanation over plum blossom-shaped catalyst
【Abstract】The simulation of methanation process is studied by CFD, and makes reasonable improvement to the model. The three-dimensional model of methanation reaction on the plum blossom-shaped catalyst was established and the validity of the model was verified. Due to strong diffusion limitations, the CO concentration of catalyst particles has great difference between the internal and external. Inside the catalyst, reaction conditions are changed to be a high H/C value. The diffusion rate of H2 is larger than that of CO. A single kinetics cannot describe the reaction accurately. The catalyst domain is divided into two parts according to the variety of CO concentration in catalyst, and different kinetics is applied into the corresponding domain. Under the control of two kinetics, the average reaction rate of methanation is accelerated, which is closer to the actual process and shows that the new model is more accurate.
【Keywords】 methanation; computational fluid dynamics; catalyst; optimal design; diffusion;
(Translated by LI M)
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