Distribution of Particle Descending Velocity in the COREX Shaft Furnace with DEM Simulation

Abstract

Screws in COREX shaft furnace are used to discharge burdens to the latter processor - the melter gasifier. They play a very important role in the uniform drawdown pattern, which directly affects the uniform gas distribution and further the smooth operation in the COREX shaft furnace. Therefore, a three dimensional model is established based on the discrete element method (DEM) in the present work. The model is used to investigate the effect of the bottom diameter of COREX shaft furnace, the cylinder height and the screw flight diameter on particle descending velocity along the radius during discharging process. Results show that the descending velocity decreases along the radial direction. It is better to decrease the bottom diameter of COREX shaft furnace, or the screw flight diameter, or to increase the cylinder height in order to achieve a uniform descending velocity along the radius. An optimization model is also proposed for uniform drawdown pattern in the end.