Experimental and Numerical Simulation Study of Elutriation Segregation Phenomenon during Gravity-Driven Flow of Powder

Elutriation segregation is a key concern in dry powder handling processes. This phenomenon becomes critical during the handling and transportation of a powder blend that contains appreciable amount of fines in presence of air. Elutriation results in a vertical segregation of particles caused by counter-current air flow in a gravity driven flow of powder. It adversely affects the final product quality, and might also result in huge financial losses due to scrapping of whole batch of the product due to non-uniformity. Recently, Procter & Gamble and ANSYS collaboratively started looking into understanding and quantifying the elutriation segregation phenomenon through experiments and simulations. The goal is to quantify the effect of powder and process parameters that affect particle segregation. A pilot scale elutriation rig is constructed to experimentally simulate this phenomenon and then further guide the modeling efforts. Eulerian-Eulerian framework is used to model this segregation phenomenon. Particle-particle interactions are modeled using Kinetic Theory of Granular Flow (KTGF), while interaction between the phases is modeled through drag and exchange terms. Experimental and simulation results of elutriation segregation will be presented.