Additive Manufactured Ceramic Internals for Small Scale Extraction Columns
S. Soboll, I.C. Stark, C. Schulze, N. Kockmann, TU Dortmund, Dortmund
K. Sauerzapfe, H. Wampers, Lapp Insulators Alumina GmbH, Redwitz
Continuous processes attain increasing interest in production of specialty chemicals and pharmaceutics, in which the amounts of produced goods are rather small. Additionally, small-scale equipment enables rapid process development in the lab with consistent scale-up capability. To improve thermal and chemical resistance and widen the operational windows, Lapp Insulators Alumina GmbH and TU Dortmund, Equipment Design have developed new concepts for small-scale plants with integrated key-components made of ceramics. Here, the development of a small scale extraction column  with ceramic components made of Al2O3and produced by 3D printing  shall be presented.
Different prototypes of stirrers, bearings, and plates were developed and their applicability in the column was evaluated. During this process, it took several iterations from design, manufacturing, and application of shaft-like geometries as stirrers for intensified dispersion in the column with internal diameter of 15 mm. Additionally, the proper fixation of the internals, which is usually done by connecting the plates and bearings by shafts, was a major challenge. The contribution will show some of the detailed solutions and achieved results already shown on the ACHEMA fair.
The column with an active height of 220 mm was investigated in terms of fluid dynamics and separation performance using the EFCE test system n-butyl acetate / acetone / water. The droplet size distribution was determined for different column loadings showing mean diameters ranging from 0.55 to 0.7 mm. Mass transfer and separation efficiency is in the same range as for the previously investigated column with metal internals  for direction disperse -> continuous and slightly lower in case of the opposite direction. Further investigations will focus on improved internals and further chemical systems.
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