Simulations of multi-size solid particles in a modified fluidized bed separator

Abstract

This study focusses on the description of the internal state of a modified fluidized bed separator also known as the reflux classifier. The device is a highperformance beneficiating technology employed in many mineral and coal processing industries. A 2D continuum model was used to examine the transport behavior of solid particles within the reflux classifier for a multicomponent mixture under continuous operating conditions. Three different types of feeds comprising solid particles of size ranging 49–421 μm and densities equal to 1400, 2490 and 5000 kg/m3 were simulated simultaneously under identical process conditions. The feed flux and fluidization velocity were kept at 0.0037 m3/m2s and 0.022 m/s, respectively. A comparison of the simulation results showed that the value of separation size shifted towards lower values, 340, 181 and 90 μm, when the density of the feed was changed from 1400 to 2490 and 5000 kg/m3, respectively. The data generated through simulations was used to demonstrate the movement of solid particle within the inclined section by plotting the net flux of the solid particles across the inclined channel width. It was observed that the net flux of finer solid particles was higher than the coarser ones within the inclined section.

Keywords

• dispersion coefficient
• fluidization
• inclined channels
• mineral processing
• segregation
• separation efficiency