Optimization of multiplicity of the catalyst circulation in the reforming reactor with moving granular bed by combination of full-scale and computer simulation

When operating the reforming units with continuous catalyst regeneration there is the problem of optimizing the multiplicity of the catalyst circulation in the reactor-regenerator. This problem can be solved with a combination of natural and computer simulation through a study of the formation of coke on the catalyst surface. Based on the results of TGA of the industrial catalyst Pt-Sn/γ-Al2O3 concluded that amorphous coke is formed on the catalyst surface in reforming process, the whose number of coke at the outlet of the reactor block is 4–6 % depending on the composition of need materials and process parameters. The specific surface area of samples (m2/g): for the original – 152, after regeneration – 140, at the outlet of the reactor – 118, which correlates with the amount of coke on the surface of the samples. Mathematical analysis of processes of coke formation in the reforming reactor, a moving granular bed showed that the multiplicity of the catalyst circulation should be maintained in the range 0,008–0,010 m3/m3 to improve the efficiency of industrial plant. Maintaining the optimum conditions in the reactor and regenerator unit will allow to control the coke formation and to maintain the coke concentration on the minimum possible, and specific surface area of the catalyst at the highest possible level.

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