CHEMICAL ENGINEERING TRANSACTIONS VOL. 69, 2018 A publication of The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Elisabetta Brunazzi, Eva Sorensen Copyright © 2018, AIDIC Servizi S.r.l. I SBN 978-88-95608-66-2; I SSN 2283-9216 Development and Application of the TUM-WelChem Cell Model for Prediction of Liquid Distribution in Random Packed Columns Florian Hanusch a, *, Volker Engel b , Robert Kender a , Sebastian Rehfeldt a , Harald Klein a a Technical University of Munich, Department of Mechanical Engineering, Institute of Plant and Process Technology, Boltzmannstr. 15, 85748 Garching, Germany b WelChem GmbH, Brunnenweg 40, 83666 Waakirchen, Germany florian.hanusch@tum.de Liquid maldistribution is, next to the prediction of interfacial phase area and mass transfer coefficients, one of the bigger uncertainties in random packed column design. In a joint project, “Cell Model for Packed Column and Liquid Distributor Design” supported by the Bavarian Research Foundation, liquid maldistribution experiments were conducted in three packed columns with diameters of 0.4, 1.2 and 2.0 m at Technical University of Munich (TUM), RVT Process Equipment GmbH and Linde AG. Experiments covered varying experimental and operating parameters – gas/liquid system, type of packing, packing height, type of liquid distributor, liquid load, and gas load. An evaluation of the acquired database provided insight into influencing factors on liquid distribution. (Hanusch et al., 2017) In 2007, Wild and Engel first presented their WelChem Cell Model. The original model predicted liquid distribution in random packing from cell layer to cell layer based on directional dispersion coefficients, deduced from virtual 3D irrigation simulations with a CAD model of one random packing element (Wild and Engel, 2007). Further development at TUM included implementation of the influencing factors liquid load and gas load, considering local loading effects and increasing liquid dispersion. Wall effects were refined by distinction of packing elements and voids at the column wall. Liquid distribution profiles predicted with the TUM-WelChem Cell Model are in good agreement with experimental data. WelChem GmbH implemented the TUM-WelChem Cell Model in their column design software TrayHeart, thus making the research results directly accessible for TrayHeart users. Application of the TUM-WelChem Cell Model ranges from prediction of maldistribution in random packed columns, through liquid distributor design, considering interactions with random packing, to process simulation, considering maldistribution in parallel column models (Schultes, 2000). 1. Introduction Mass transfer calculations for random packed columns generally assume even distribution of gas and liquid over the column cross-section. However, liquid channelling and an increased wall flow are well-known liquid maldistribution phenomena, resulting in uncertainties in random packed column design (Mersmann et al., 2011). Experimental investigation of liquid maldistribution reaches back to the late 19 th century, when Hurter measured the liquid distribution in a coke tower (Hurter, 1893). An extended review of liquid maldistribution experiments and observations on important influencing factors is given in Hanusch et al. (2017). Insight gained via experimental investigations can be used for the development of theoretical models for the prediction of liquid maldistribution in packed columns. One approach to describe the liquid distribution in random packing applies the mathematical laws of probability (Tour and Lerman, 1944). Another type of model, derived from the probability approach, characterises liquid distribution as a diffusional process (Cihla and Schmidt, 1957). The aforementioned models consider liquid distribution on a differential scale. Cell models on the other hand discretise the packing with a resolution of the size of single packing elements or bigger (Crine DOI: 10.3303/CET1869124 Please cite this article as: Hanusch F., Engel V., Kender R., Rehfeldt S., Klein H., 2018, Development and application of the tum-welchem cell modell for prediction of liquid distribution in random packed columns, Chemical Engineering Transactions, 69, 739-744 DOI: 10.3303/CET1869124 739