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Wire mesh packing has been extensively utilized in laboratory and industry applications in rotating packed bed (RPB) because of the high mass transfer performance and low cost. Conventional wire me...

A novel disk-distributor rotating packed bed (DRPB) was developed in this study to promote the application of RPBs for high-viscosity processes. A rotating disk was used as a liquid distributor in the inner cavity of the DRPB to distribute a high-viscosity liquid, and the porous packing was anchored radially outside the disk to additionally disperse the incoming liquid. Three-dimensional Eulerian multiphase simulations were implemented to examine the liquid flow characteristics in the packing after experimental validation. With increasing viscosity (μ) from 11 mPa·s to 59372 mPa·s, flow patterns were transformed from dispersive into continuous modes. Liquid holdup, which ranged from 0.0006 to 0.25, was proportional to μ0.61. Wetting efficiency and wetting height varied in ranges of 0.0012–0.416 and 3.03–14.57 mm, respectively. At a viscosity of 3331 mPa·s, approaches involving the use of multistage DRPB and the installation of redistribution blades improved the axial utilization efficiency of the packing from 20% to 80% and 20% to 92%, respectively.

Mesh packing in rotating packed bed reactors has been intensively exploited. As a crucial parameter of mesh, fiber cross-sectional shape was expected to affect the liquid flow behavior inside packing. Herein, liquid jet impacting on rotating single-layer meshes with various fiber cross-sectional shapes, including circular, elliptical, and quadrangular, were investigated. Liquid flow pattern and dispersion characteristics were studied by visualization. Details of liquid impact-disintegration process and internal velocity and pressure fields were presented via simulation. The curved surface allowed liquid to flow around fiber and converge again, then generated liquid ligaments and films perpendicular to the rotational axis. The sharp edges of quadrangular fiber hampered separated liquid to converge, thus generating liquid films parallel to the rotational axis. The mesh composed of vertical quadrangular fiber and horizontal elliptical fiber reduced average droplet diameter by 16% and liquid maldistribution index by 14% compared to mesh with circular fibers, intensifying liquid dispersion.

In this work, the gas–liquid mass transfer performance of rotating packed bed (RPB) with Al2O3 sphere packing, in term of volumetric liquid-side mass transfer coefficient (kLae), was investigated by CO2-NaOH chemical absorption system. The adsorption performance of Al2O3 spheres was also evaluated by an ink adsorption method. Results showed that the kLae values of RPB with Al2O3 sphere packing were higher than those of RPB with nonporous sphere packing, and over one magnitude order higher than those of trickle bed reactor (TBR) with Al2O3 sphere packing. The ink adsorption, film diffusion and pore diffusion rates of Al2O3 spheres have been greatly improved under the high gravity field, and it has been found that the surface tension was the main driving force of ink adsorption. Moreover, the adsorption kinetics was investigated and the experimental data fitted well with the pseudo-first-order adsorption kinetics model.

The biocatalytic oxidation exists widely in biochemical industry. However, the oxidation reaction rate is usually limited by oxygen mass transfer. In this work, an inner-loop rotor-stator reactor (IL-RSR) was employed as a promising reactor for the process intensification of oxygen mass transfer, aiming to match the rate of oxidation reaction. The oxygen mass transfer coefficient (kLa) of the IL-RSR was experimentally studied. Then, the biocatalytic oxidation of glucose to produce sodium gluconate (SG) was selected as an example of working system to evaluate biocatalytic oxidation performance of the IL-RSR. The results indicated that the experimental value of kLa was in the range of 0.00984∼0.02758 s−1 in the IL-RSR. The SG production rate was up to 6∼12 g/(L·h) in the IL-RSR, which was 7 times that in a stirred tank reactor (STR). IL-RSR shows potential prospects in the field of biocatalytic oxidations.