In this work, the results of single phase CFD simulations of mixing vessels with four baffles agitated by a Rushton turbine are used to determine the parameters of a two‐compartment model that describes the turbulent non‐homogeneities therein. An improved method is proposed to find the boundary between the two characteristic regions. Using this method, the effects of different conventional scale‐up criteria including constant impeller speed, constant impeller tip speed and constant power consumption per liquid volume, on the value of the compartmental model parameters are investigated. It can be observed that the distribution of the turbulent energy dissipation rate and, as a result, the compartmental model parameters change considerably when following conventional scale‐up rules. The concept of a general map of compartment energy dissipation rate and volume ratios, which can be used for the scale‐up of stirred tanks, is introduced.

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A simulation model is developed using ASPEN PLUS to predict the performance of a fluidized bed membrane reformer. Because there are physical and chemical phenomena interacting in the fluidized bed membrane reformer, two submodels seem necessary in the model. These submodels are the hydrodynamic and reaction submodels. The hydrodynamic submodel is based on the dynamic two-phase model, and the reaction submodel is derived from the literature. The reformer is divided into two regions: a dense bed and freeboard. The dense bed is divided into several sections. At each section, the flow of the gas is considered as the plug flow through the membrane and bubble phases and perfectly mixed through the emulsion phase. The sets of the experimental data were used from the literature to validate the model. Close agreement was observed between the model predictions and experimental data. This model can be used for the simulation of nonideal fluidized bed membrane reactors inside the ASPEN PLUS process simulator.

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