(581c) Pressure Drop Modeling for Heterogeneous Contacting Schemes: Pleated Microfibrous Entrapped Catalyst At High Face Velocity

A unique class of composite microstructured contacting system called microfibrous entrapped catalyst (MFEC) was prepared by the traditional high speed and low cost paper making technique. The micron sized (4- and 8- μm) metal fibers (Ni-200) can entrap small particles of γ-Al₂O₃ (150-250 μm) into sinter-locked matrices and form thin flexible sheets (3.6 mm). The pressure drop through the catalysts containing material is a vital factor in reactor design. In this work, pressure drops were measured at high face velocities (10-30 m/s) across a pleated MFEC (Number of pleat 1 and 4) structure. Traditional pressure drop models use a mixing rule for components with different diameters, but this tends to yield significant errors due to the differences in the dimension between the fibers and the entrapped particles. A semi-empirical model equation, called porous media permeability (PMP) equation, along with a correction factor for dealing with the heterogeneity of entrapped catalyst particles, and a pleat factor term for estimating decreased velocity inside the media due to pleating, is presented for predicting pressure drops across a pleated MFEC. The developed pressure drop equation has shown reasonable agreement with the experimental results with an error less than 0.10 kPa and 0.19 kPa for number of pleat 1 and 4 at 200°C, respectively. The equation accurately predicted the pressure drops for comparatively low face velocities and underpredicted for high face velocities due to the absence of the inertial losses at the entrance and exit positions.