Investigation of hydrodynamics and mass transfer of solid foam packings for gas-liquid applications

Chemical reactors with a fixed bed of catalyst particles are widely applied in the chemical industry. However, the performance of these reactors often suffers from some drawbacks, such as high energy consumption caused by pressure loss and low productivity due to mass and heat transfer limitations. One solution is to replace catalyst particles with catalysts packings based on solid foams with an open cell structure. Such porous structures combine large specific surface areas, high bed porosities, and interconnected pores for enhanced heat and mass transfer (Zhang et al. 2012). The performance of reactors with solid foam catalysts depends on the interaction of the fluids with the foam structure and, hence, the mass transfer to the foam surface. These two aspects are directly linked to the overall reactor performance and need to be understood in detail for reactor design. This work focuses on an experimental investigation of hydrodynamics and mass transfer. The hydrodynamics investigation was based on applying novel wire-mesh sensors to study gas and liquid distribution at high spatial resolution. The particular liquid-solid mass transfer was studied by a modified electrochemical method. The experiments are based on the measurement of electrical current under mass transfer diffusion limited condition. The experimental results of this work demonstrate clearly the potential of solid foam as suitable packing for gas-liquid applications.