Advanced Powder Technology, Vol.28, No.11, 2961-2973, 2017
Experimental study and discrete element method simulation of Geldart Group A particles in a small-scale fluidized bed
Geldart Group A particles are of great importance in various chemical processes because of advantages such as ease of fluidization, large surface area, and many other unique properties. It is very challenging to model the fluidization behavior of such particles as widely reported in the literature. In this study, a pseudo-2D experimental column with a width of 5 cm, a height of 45 cm, and a depth of 0.32 cm was developed for detailed measurements of fluidized bed hydrodynamics of fine particles to facilitate the validation of computational fluid dynamic (CFD) modeling. The hydrodynamics of sieved FCC particles (Sauter mean diameter of 148 mm and density of 1300 kg/m(3)) and NETL-32D sorbents (Sauter mean diameter of 100 mm and density of 480 kg/m(3)) were investigated mainly through the visualization by a high-speed camera. Numerical simulations were then conducted by using NETL's open source code MFIX-DEM. Both qualitative and quantitative information including bed expansion, bubble characteristics, and solid movement were compared between the numerical simulations and the experimental measurement. The cohesive van der Waals force was incorporated in the MFIX-DEM simulations and its influences on the flow hydrodynamics were studied. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
Keywords:Discrete element method;Fluidized bed;Group A particles;Bed expansion;Cohesive force;High-speed image