In this research we focus on three-phase gas-solid-liquid multi-component systems with catalytic particles, which are frequently encountered in industrial applications, but have not been tackled fundamentally before due to their complexity.
Dense multi-phase flows have been intensively researched because of their scientifically interesting transport phenomena and industrial applications. Considerable progress has been made for gas-solid and gas-liquid two-phase flows. However, multicomponent three-phase flows with catalytic reactions have received relatively little attention despite their importance for the production of clean synthetic fuels, base chemicals, and many other products. Multiphase transport phenomena in such systems are poorly understood due to their complexity. Therefore, the design of such processes is cumbersome, requiring extensive experimentation. In addition, the process operation is often far from optimal in terms of energy and feedstock utilization. Therefore, significant improvements are required to boost the efficiency of three-phase systems, which demands for a better understanding of the transport fundamentals and complex interplay with catalytic reactions and availability of predictive tools.
The main underlying problem is the complex interplay between transport phenomena and catalytic reactions, introducing a wide range of length scales: suspended catalyst particles have a size of 100-200 μm, whereas the diameter of industrial reactors is 5–10 meters. To tackle this type of problem, a proper problem decomposition needs to be adopted. At the scale of the particles, the catalytic reactions need to be considered as well as the transfer of species and heat to the continuous (liquid) phase. The latter is accounted for by closure laws for mass, momentum and heat exchange that feed so-called Euler-Lagrange models, which can then be used to compute the flow structures on a much larger (industrial) scale. The key innovative aspect of this proposal is the integrated approach including incorporation of multi-component catalytic reactions and supporting experimental validation on basis of one-to-one comparison of the computational results with experiments.
