To separate solid particles from liquid suspensions by a porous filter medium, suitable methods are e.g. surface filtration, depth filtration or cross flow filtration. As porous filter medium, nonwoven or woven fabrics, sintered particles or membranes with open-pored foam structures are applied in single or multiple layers.
The efficiency of the filtration process and consequently the purity of the filtrate can be improved by choosing or designing appropriate filter media and by adjusting the process parameters. To achieve this, the particle separation process must be understood and described precisely. Since pore clogging, detachment and re-entrainment of particles and agglomerates occur frequently in filtration processes of suspensions, these effects must also be taken into account.
For the 3D numerical simulation of such filtration processes on the pore scale of the filter medium, the fluid dynamics in the pore space as well as particle-particle and particle-structure collisions have to be considered, which can be achieved by coupling computational fluid dynamics (CFD) with the discrete element method (DEM). In this contribution we describe the results of the coupled Lattice-Boltzmann method for the fluid flow simulation and the discrete element method for the particle simulation using the software DNSlab. Simulation studies are presented which are compared to experimental and literature data. The practical applicability of this numerical approach is discussed regarding the scalability to large systems with many particles...
Session: L3 - Cake Filtration - Modelling, Simulation, Characterization
Day: 13 March 2018
Time: 16:45 - 18:00 h