TY - JOUR A1 - Schwarz, Benedikt A1 - Ortler, Matthias A1 - Lindner, Johannes T1 - Rotational speed change and reverse mixing to avoid baffles in dispersing processes JF - Chemical Engineering Research and Design N2 - Stirring is used for mass and heat transfer, particle suspending or similar processes. It is commonly conducted in a steady operation mode. This paper targets on performing the stirring process dynamically by reversing the rotation direction to introduce additional turbulences and hence accelerating the dispersing processes. The power introduced into the fluid as well as mixing kinetics performing dynamic mixing were studied based on the rotational acceleration, blade pitch angle, liquid volume and duration of the rotational speed direction interval for a vessel equipped with a turbine agitator with and without baffles. Experiments show that baffles are not necessary if reverse mixing is performed at a specific frequency. KW - agitating KW - dispersion KW - dynamic mixing KW - reverse mixing KW - rotational direction change KW - stirring Y1 - 2024 U6 - https://doi.org/10.1016/j.cherd.2024.05.004 VL - 206 SP - 302 EP - 309 ER - TY - JOUR A1 - Schwarz, Benedikt A1 - Kniele, H. A1 - Lindner, Johannes T1 - Automated Process Optimization in a Novel TripleShaft Mixer with Adaptive Mixing Modes JF - Chemie Ingenieur Technik N2 - A novel multi-purpose mixer was set up, which allows the change of the blade angle during the process and provides aflow field with respect to the needs of the mixing task. It features as well as a coaxial stirrer for highly viscous liquids andhence has three degrees of freedom. The stirrer considers the integration and validation of an optimization strategy forthe autonomous identification of an optimum operating point based on automated tests. The validation was conducted ina mixing process with several process input parameters, which is commonly used in industrial applications. The powerdraw of the main stirrer was used as a optimization parameter, representing the power used for dispersing. The speedand direction of the main and secondary stirrers, respectively, as well as the angle of the stirrer blades, were used as inputprocesses. The proposed control scheme automatically identifies and corrects drops in energy dissipation rates. KW - Mixing KW - Optimal operation KW - Reinforcement learning KW - Self-optimization Y1 - 2025 U6 - https://doi.org/10.1002/cite.70060 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schwarz, Benedikt A1 - Krause, Peter A1 - Lindner, Johannes T1 - A Dynamic Hydrocyclone Adapting to Different Operating Points by Changing the Inlet Area JF - Chemical Engineering and Technology N2 - In this study, a novel hydrocyclone design was developed featuring a variable inlet geometry, which enables adjustment of the inlet area during operation. This allows control over the flow velocity within the cyclone, thereby maintaining a constant tangential velocity despite changes in volumetric flow rate. The prototype demonstrated a constant separation efficiency across a volumetric flow range spanning a factor of two between its minimum and maximum capacities. Two control strategies were investigated: operation at constant pressure drop and operation at constant inlet velocity, both under varying flow rates and inlet geometries. To initially examine the influence of key parameters, hydrocyclones with fixed geometries were fabricated using rapid prototyping and employed in experimental trials. These findings informed the subsequent development and construction of a dynamically adaptive steel prototype capable of dynamic geometrically adjustment. KW - dynamic hydrocyclone KW - particle separation KW - solid–liquid separation Y1 - 2026 U6 - https://doi.org/10.1002/ceat.70154 PB - Wiley-VCH CY - Weinheim ER -