DEM simulation of particle descending velocity distribution in the reduction shaft furnace

Abstract

Reduction shaft furnace is a promising alternative to blast furnace ironmaking. The particle descending velocity distribution has a great influence on the shaft furnace, which directly affects the production index and further the shaft furnace normal smelting. Therefore, a three-dimensional model (3D) is established based on the discrete element method (DEM) and computation fluid dynamic (CFD). The effect of the gas flow in the shaft furnace, the height, the diameter and the bosh angle of the shaft furnace on the particle descending velocity distribution during discharging process is investigated by the model and analyzed based on the granular dynamic theory and Janssen theory. The results show that the particle velocity reduces along the radius. The effect of the gas flow on the velocity distribution is insignificant. In order to obtain a uniform velocity distribution, it is better to increase the height, or the diameter, or to decrease the bosh angle. An improved model is proposed for the uniform velocity distribution at last.