Solids Process Engineering in Life Sciences
The processing of solids and powder is an important step in diverse pharmaceutical and food processes. The chair is able to reproduce experimentally the processing chain from conveying, milling mixing, granulating to tableting of the final product. It can be reproduced as well by simulation (CFD, Discrete Element Method). The analytical investigation is possible by laser diffraction, electronic capacitance tomography, pyncometer, BET method, water activity measurement, micro-computed tomography etc. is possible.
Hot Melt Coating
A special focus is the investigation of hot melt coating. In this case coating is liquefied by melting, and solidified by cooling after applying on a particle. This is possible with natural products like beeswax or carnaubawax, which do not need to be declared as a food additive. In contrast to common, solvent-based coatings the process fast and efficient, as it is not necessary to evaporate an additional solvent. The realization is more complex for the extended temperature range of the crystallization process, the formation of crystals and the rheological behavior. For the implementation a lab-scale fluidized bed was equipped with a heated preprocessing unit. Additionally the coating crystallization on a single particle fluidized in the freestream (levitator) can be monitored under defined conditions. Coating layers are investigated by micro-computed tomography.
Lab scale fluidized bed with heated preprocessing (left); Particle in a levitator (right)
A focus oft he reasearch group ist he investigation of press agglomeration in simulation and experiment. A new approach allows the simulation of press agglomeration and breakage in one single model.
DEM-Simulation einer Tablette im Bruch (links); Pulver vor der Verpressung und nach der Verpressung im Computertomographen und gebrochene Tablette (rechts)
Intelligent Unit Operations
Diverse processes are not used optimally, as they are operated manually or by simple PID-elements. The cheap availability of microcontrollers and diverse sensors allows to gain more information on the process. The target of the workgroup is to equip unit operations in industrial cooperation with additional cost-efficient sensors and control them in an intelligent way. The microcontroller identifies efficient operating parameters and controls the process in an optimal way. Adequate are instationary processes, as well as instable process, which do not dispose of a stable operating point.
Pneumatic Dense Phase Conveying
Pneumatic dense phase conveying is investigated in the workgroup. A conveying tube in industrial scale is available, which is equipped with diverse measurement techniques such as fine pressure sensors for the measurement of pressure loss in single plugs, wall shear stress sensors in radial and tangential direction, as well as an electronic capacitance tomograph, which resolves the plug porosity all over the tube with a resolution of 4000 /s.
Measuring device in the pneumatic conveying line (left); Porosity distribution in the tube (right)
For further information please contact:
Dr.-Ing. Johannes Lindner