(159ad) Experimental and Numerical Investigations of the RTD in a Gea Consigma CTL25 Tablet Press

The knowledge of the residence time distribution (RTD) of pharmaceutical unit operations is vital for the development of control strategies for continuous manufacturing lines. The present contribution addresses the validation of experimentally determined RTD with numerical results for the tablet press of the GEA ConsiGma CTL25 line.

Various experimental investigations are available which focus on the determination of the RTD in tablet presses via costly tracer experiments (see e.g. [1] and [2]). Due to high computational expenses the numerical examination of the RTD in tablet presses has not been demonstrated before. Previous work [3] showed the potential to calculate the RTD by the means of DEM simulations. We further apply the DEM approach, overcome the computational limitation with a time scale extrapolation method and validate our results with experimental data. Our approach yields the potential to complement experimental DoE runs with numerical simulations and enhance the understanding of material behavior inside this complex unit operation.

Most importantly, the present contribution addresses the following topics: (i) experimental determination of the RTD in a Design-of-Experiment (DoE) wise approach, (ii) characterization and calibration of the investigated material, (iii) the numerical setup similar to prior performed experiments and (iv) validation of the RTD with experimental data.

[1] R. Furukawa, R. Singh, and M. Ierapetritou, ‘Effect of material properties on the residence time distribution (RTD) of a tablet press feed frame’, Int. J. Pharm., vol. 591, Dec. 2020.

[2] M. Dülle, H. Özcoban, and C. S. Leopold, ‘Investigations on the residence time distribution of a three-chamber feed frame with special focus on its geometric and parametric setups’, Powder Technol., vol. 331, pp. 276–285, May 2018.

[3] E. Siegmann et al., ‘Powder flow and mixing in different tablet press feed frames’, Adv. Powder Technol., vol. 31, no. 2, 2020