Apparent viscosity of binary particle system in gas-solid separation fluidized bed

Abstract

The apparent viscosity of binary particles has a crucial impact on the efficiency of gas-solid separation fluidized bed. Herein, apparent viscosity of the binary particles consisting of magnetite and coal particles was measured by the falling ball method. The test results indicate that the apparent viscosity of binary particles decreased with the increase in coal powder. When the mass fraction of coal increased by 2%, the apparent viscosity, on an average, decreased by 0.12 Pa·s, and dropped by half with increase in operating gas speed from 9.5 cm/s to 12.2 cm/s. The adjustment of gas velocity and magnetite powder content can effectively reduce the apparent viscosity and improve the separation efficiency, without changing the bed density. A modified model has been developed for predicting the apparent viscosity of binary particle. The model performed well in estimating the viscosity with an overall standard deviation of 13.00% from experimental results.