(123b) A CFD-DEM Analysis of Particle Attrition in a Cyclone

Cyclones are used to separate entrained particles from the flue gas streams. Particles entering a cyclone are subjected to a radial centrifugal force field, driving them to the cyclone walls, where they experience collisional and rapid shearing stresses. For frangible particles this could lead to attrition and dust generation, whilst for hard particles wear of cyclone wall could occur.

In this work we address the issue of attrition of manganese di-oxide particles used in the CLC process. A CFD-DEM analysis of particle motion and interactions is used to calculate the frequency of collisions, impact velocities and shear stresses. These are then coupled with a model of particle breakage due to impact and of surface wear, in order to predict attrition in a cyclone. The outcome of the work is presented, providing a correlation of the attrition extent as a function of particle properties and operating conditions.