An Investigation of the Effect of Particle Size on the Flow Behavior of Pulverized Coal

In this paper, pulverized coal from industry was used as the experimental material and sieved into seven samples with different particle size. The effect of particle size on the flow properties of pulverized coal was investigated. An annular shear cell was used to measure angle of internal friction, angle of effective internal friction, cohesion and angle of wall friction, and a transparent Perspex hopper was used to determine the discharge characteristics of pulverized coal. The experimental results showed a significant effect of particles size on the cohesive and angle of wall friction rather than on the angle of internal friction. Jenike's procedure was used to predicate the flow pattern of pulverized coal with different particle size, which linked with the discharge experiment. Three regions including arching, unstable-flow and mass-flow were obtained based on the analysis of weighting curves and a progressive transition from blocking to unstable flow and to mass flow was observed as the particle size increased. In addition, the failure properties of pulverized coal was investigated which supported the region division. The investigation showed that the effect of particle size on the flow properties of pulverized coal is diversity and rheological test results can reflect flow properties of pulverized coal to some extent.