Using DEM-CFD to model colloidal particles aggregation in water Florian Chaumeil and Martin Crapper School Engineering, The University of Edinburgh, UK www.see.ed.ac.uk/IIE/research/environ/ INTRODUCTION EDEM Academic was used to simulate how micron-scale spherical latex particles immersed in water agglomerate and deposit when flowing passed constraining geometries. EDEM post-processing capabilities allowed to identify key mechanisms of colloidal particle capture and re-suspension involved in water purification. • RESEARCH GOALS • This study took place between May 2009 and November 2012, with the idea that DEM could be a useful tool in investigating colloidal particle retention in the micro-structures of granular and membrane water filtration. EDEM Academic was used to assess the capability of coupled DEM-CFD to simulate: • Colloidal suspension flowing through a constricted tube • Bio-fouling of membrane spacer • METHODS • Filtration processes were scaled-down to computationally efficient model units • EDEM Field Manager was used to import CFD velocity field • EDEM Academic API was used to load custom contact plug-ins that implemented interfacial forces and wall retardation effects. Custom Force plug-ins were also used to implement drag, lift and Brownian forces. • EDEM Academic post-processing abilities were used to extract simulation data, pictures and movies form the simulations RESULTS Simulations of initial Bio-fouling on membrane spacer using EDEM Academic allowed to predict preferred deposition patterns at the filaments’ junction of membrane spacers: • Simulations of colloidal suspension flowing through a constricted tube using EDEM Academic allowed to identify: • Mechanisms of cluster formation for various particle sizes and concentrations • Mechanisms of particle deposition, scouring and re-suspension ENVIRONMENTAL ENGINEERING RESEARCH CONTACTS Florian Chaumeil email@example.com Dr Martin CrapperMartin.Crapper@ed.ac.uk+44 131 650 5727 CONCLUSIONS EDEM Academic offered a customisable framework that enabled to include complex colloidal physics and easy coupling with CFD results. Simulations confirmed postulated mechanisms of particle retention that are important in the field of water treatment.