Contact

Dr. Philipp Wiedemann

p.wiedemannAthzdr.de
Phone: +49 351 260 2467

Dr. Markus Schubert

m.schubertAthzdr.de
Phone: +49 351 260 2627

Tools and Methods for an Improved Fluid Dynamic Design of Column Trays with Fixed and Push Valves

Motivation and Objective

Tray columns are applied in the chemical industry and serve for the thermal separation of multicomponent mixtures. Due to the increasing energy supply from renewable sources a more flexible operation of such apparatuses is required. However, since high separation efficiencies need to be maintained in the associated partial load and overload scenarios, the design process becomes a challenging task. Particularly the design of high performance trays with fixed and/or push valves suffers from missing tools and methods for estimating the influence of the tray design on the complex two-phase flow of liquid and vapor as well as the operation limits.

Therefore, the collaborative iGF-project of HZDR, TU Munich and Ruhr-Universität Bochum aims at closing this gap and extensive experimentation will be conducted in order to characterize the two-phase flow on valve trays in dependence of valve type, valve number, valve arrangement as well as operating conditions and fluid systems. Based on the experimental results models are subsequently developed and will allow for facilitating the design process of high performance trays with fixed and push valves in practice.

HZDR subproject

The subproject of the Institute of Fluid Dynamics at Helmholtz-Zentrum Dresden-Rossendorf is divided in two parts. In the first part a two-dimensional sensor array is specially designed and constructed for the application in the large-scale facility of TU Munich in order to characterize the two-phase flow on the test trays. The custom-made sensor array allows for measuring a three-dimensional distribution of the temporally averaged phase fractions above the tray as well as the average liquid velocity by additionally using a tracer solution.

https://www.hzdr.de/db/Pic?pOid=62861
Sensor array

In the second part a coarse-grid CFD approach is developed, which enables investigating the influences of valve type, valve number and valve arrangement on the macroscopic flow structures by numerical simulations. The individual valves will be modeled by point-like mass and momentum sources. For validation purposes experiments are carried out with a lab-scale test rig that allows for detailed investigations of single valves and valve groups under pre-defined operating conditions. These investigations will make use of sophisticated in-house measurement techniques in order to gain detailed information on flow fields and patterns. In order to demonstrate the capabilities of the CFD model for simulating the two-phase flow in industrial-scale units, simulations of the TU Munich facility will be compared with related experimental data.

Foto: Eye-Catcher ColTray-CFD ©Copyright: Dr. Philipp Wiedemann

Simulated phase distribution on a distillation tray with fixed valves

Source: Dr. Wiedemann, Philipp

Download

Further details on the project structure and the tasks of our partners are available on the project website: https://www.hzdr.de/coltray

Project partners

The project is carried out collaboratively with TU Munich and Ruhr-Universität Bochum and supported by numerous industrial partners:

  • RVT Process Equipment GmbH
  • WelChem GmbH
  • BASF SE
  • Covestro Deutschland AG
  • ENVIMAC Engineering GmbH
  • Evonik Technology & Infrastructure GmbH
  • Horst Weyer & Partner GmbH
  • HZDR Innovation GmbH
  • IBE Ingenieurbüro Bulander & Esper GmbH
  • Linde GmbH, Linde Engineering
  • Raschig GmbH

Acknowledgment

Foto: BMWK logo en ©Copyright: BMWK

The project was funded by the Federal Ministry for Economic Affairs and Climate Action in frame of iGF-grant 20835 BG.

Duration: 01.03.2020 - 30.09.2023

Industrielle Gemeinschaftsforschung IGF-Vorhaben 20835 BG/1

Publications

  • Wiedemann, P.; Meller, R.; Schubert, M.; Hampel, U.:
    Application of a hybrid multiphase CFD approach to the simulation of gas–liquid flow at a trapezoid fixed valve for distillation trays
    Chemical Engineering Research and Design 193 (2023) 777-786, doi: 10.1016/j.cherd.2023.04.016
  • Wiedemann, P.; Kota, S.P.; Weckesser, S.; Schleicher, E.; Schubert, M.; Hampel, U.:
    Numerical Simulation of the Two-Phase Flow at a Single Trapezoid Fixed Valve Using a Hybrid CFD Approach
    12th International Conference on Distillation & Absorption 2022, Toulouse
  • Vishwakarma, V.; Wiedemann, P.; Schleicher, E.; Schubert, M.; Hampel, U.:
    A new approach for estimating the effective froth height on column trays
    Chemical Engineering Science 231 (2021) 116304, doi: 10.1016/j.ces.2020.116304