Analysis of Particle Size Segregation at Bell-less Top of Blast Furnace by Discrete Element Method

The objective of this paper is to analyse the particle size segregation during charging at the bell-less type charging system of the blast furnace. The charging behavior of the sintered ore particle was simulated by using Discrete Element Method (DEM). The sintered ore particles (number of particles: n(ore) = 620231) were charged in the hopper, and the coke particles (n(coke) = 112712) were stacked at the top of blast furnace. The particles in the chute were pressed up against the chute wall with moving toward the outlet because of the centrifugal force of the chute rotation. The strong particle segregation was seen at the outlet; the most of smallest particles were upper area. It was found that the particle motion during flowing the chute was twisted in the simulation. The specific charged mass at charging area increases with increasing the number of charges, and the distribution of charged mass becomes widened toward the center of blast furnace, because the particles slide downward along with the slope of heap. Thus, DEM can give the particle size segregation during charging process of bell-less top in detail, and this is very informative tool for the optimization of charging process