Fields of Research

Dividing Wall Columns allow the separation of ternary mixtures into the pure components in only one column shell by the application of a partitioning wall inside the columns. Due to considerable reductions in CAPEX and OPEX, these columns are nowadays widely applied in chemical industry and can be considered as a mature technology. By adding additional partitioning walls this concept can be extended to quaternary separations. Further reduction of CAPEX and OPEX becomes likely. However the complexity of these units is highly increased and none of these Multiple Dividing Wall Columns have ever been realized.

Our work focuses on the fundamental understanding of Multiple Dividing Wall Columns based on rigorous modeling, simulation and multi criteria optimization. After 4 years of development we were able to build the first multiple dividing wall column on mini-plant scale an started operation in November 2021.

The project is devided in several sub-projects addressing questions of modeling and simulation of the dynamic beahaviour in particular, mathematical optimization (multi criteria optimization) and practical aspects of design, control and operation of the column.

Funded by: Deutsche Bundesstiftung Umwelt (DBU), Az.: 34815/01; Deutsche Forschungsgemeinschaft (DFG), Az.: 665461

Involved Members: Dr.-Ing. Lena-Marie Ränger, M.Sc. Lea Trescher, M.Sc. Yannick Waibel

Key Publications:

  1. Ränger, Lena-Marie; Preißinger, Ulrich; Grützner, Thomas: Robust initialization of Rigorous Process Simulations of Multiple Dividing Walls Columns via Vmin Diagrams ChemEngineering, 2(2):25, 2018; DOI: 10.3390/chemengineering2020025
  2. Ränger, Lena-Marie; Preißinger, Ulrich; Grützner, Thomas: Multiple Dividing Wall Columns - Current Status and Future Prospects, Chem. Ing. Tech., 91 (4), 2019, 420 - 428; DOI: 10.1002/cite.201800080
  3. Preißinger, Ulrich; Ränger, Lena-Marie; Grützner, Thomas: Design Considerations of Simplified Multiple Dividing Wall Pilot Plant, ChemEngineering, 3, 34, 2019; DOI: 10.3390/chemengineering3020034
  4. Ränger, Lena-Marie; v. Kurnatowski, Martin; Bortz, Michael; Grützner, Thomas: Multi-Objective Optimization of Dividing Wall Columns and Visualization of the High-Dimensional Results, Computers & Chemical Engineering , 142, 2020, 10705, DOI: 10.1016/j.compchemeng.2020.107059
  5. U. Preißinger, G. Lukac, I. Dejanovic, T. Grützner: Investigation of Control Structures for a 4-Product Laboratory Multiple Dividing Wall Column Using Dynamic Simulation, Chem. Eng. Tech., 44 (2), 223 - 237, 2021, DOI: 10.1002/ceat.202000557
  6. L. Ränger, L. Trescher, M. v. Kurnatowski, M. Bortz, T. Grützner: Vapor and liquid split flexibility in dividing wall columns in relation to the theoretical stage allocation, Chemical Engineering and Processing - Process Intensification, 2021, 163, 108365, DOI: 10.1016/j.cep.2021.108365
  7. U. Preißinger, G. Lukac, I. Dejanovic, T. Grützner: Impact of Various Feed Properties on the Performance of a Control System for a Multiple Dividing Wall Column, ChemEngineering, 2021, 5, 29, DOI: 10.3390/chemengineering5020029
  8. L. Ränger, T. Grützner: Shortcut Method for Initialization of Dividing Wall Columns and Estimating Pareto-Optimal NQ-Curves, Chemical Engineering and Technology, 44 (10), 2021; 1919 - 1928, DOI: 10.1002/ceat.202100256
  9. T. Seidel, L. Ränger, T. Grützner, M. Bortz: Simultaneous simulation and optimization of multiple dividing wall columns, Computers & Chemical Engineering, published online 2021, DOI: 10.1016/j.compchemeng.2021.107607

Additive Manufacturing (3D-Printing) allows the generation of structures that cannot be made by conventional manufacturing processes. This opens the window to entirely new concepts in thermal process engineering. We are aiming to improve the perfomance and scalability of laboratory equipment with special focus on distillation. Our packings show good performance in terms of separation efficiency (HETP), pressure drop, reproducibility and liquid distribution. In particular, we succeeded in developing packing structures that exhibit virtually constant separation performance over a wide range of gas loading. These packings are therefore well suited for the application of scalable laboratory columns. The diameter of columns we use in the lab for sclae-up experiments can be reduced to DN20.

Our developments include all relevant components of columns (beside the packing): jacket, liquid distributors, sampling trays, side draw trays etc. All components are computer generated and can be adapted quickly. The characterization is done on the basis of CFD simulations and in self-developed test rigs in the laboratory.

In perspective, we want to transfer our methods developed on simple distillation columns to dividing wall columns and absorbers.

In a further subproject we investigate the interaction of liquids on 3D printed surfaces. In this context, static and dynamic contact angles are investigated and the attempt is made to change them by specific manipulation of printing parameters.

Funded by: BASF SE (Ludwigshafen) and from its own financial resources.

Involved Members: M.Sc. Johannes Neukäufer, M.Sc. Adel M. Ashour

Key Publications:

  1. Neukäufer, Johannes; Hanusch, Florian; Kutscherauer, Martin; Rehfeldt, Sebastian; Klein, Harald; Grützner, Thomas: Methodology for the Development of Additively Manufactured Packings in Thermal Separation Technology , Chemical Engineering & Technology, (42) 9, 1970 - 1977, 2019, DOI: 10.1002/ceat.201900220
  2. J. Neukäufer, B. Seyfang, T. Grützner: Investigation of Contact Angles and Surface Morphology of 3D-Printed Materials, Industrial & Chemical Engineering Research, 59 (14), 2020, 6761 - 6766, DOI: 10.1021/acs.iecr.0c00430
  3. J. Neukäufer, N. Sarajlic, H. Klein, S. Rehfeldt, H. Hallmann, C. Knösche, T. Grützner: Flexible distillation test rig on a laboratory scale for characterization of additively manufactured packings, AIChE Journal, 2021, published online, DOI: 10.1002/aic.17381

Rotating extraction centrifuges are in the focus of this project. These devices allow a very efficient separation of liquid phases due to high g-forces. Within a relatively small volume extraction centrifuges realize one theoretical stage. Our research aims to establish these modules in the context of flexible and modular production facilities as well as the intensification by performing reactive-separations. A current focus is the study and understanding of the complex fluid dynamic processes within the apparatus.

Funded by: German Scholar Organization (CSO/CZS 21) and own financial resources.

Involved Members:  M.Sc. Zaid Hamamah

Key Publications:

  1. Z. Hamamah, T. Grützner: Liquid-Liquid Centrifugal Extractors: Types and Recent Applications - a Review, ChemBioEng Reviews, 2021, accepted, DOI: 10.1002/cben.202100035

The project aims to recover valuable components as proteins or antioxidant components from food waste streams. Overall, the objective is to increase resource efficiency by applying process engineering in the food industry.

Involved Members: Lena-Marie Ränger