Experimental Study of the Effects of Operation Conditions on Burden Distribution in the COREX Melter Gasifier

摘要

The melter gasifier (MG) is the core unit in the COREX process for the final melting and reduction of iron. This work performed an experimental study to investigate the effects of charging pattern, burden bed height and burden material type on the burden distribution in a MG. The ore and coal (coke) were discharged intermittently to a 7.5:1 scaled-down model of a typical COREX MG. After the burden surface reached to a steady state, the burden was analysed in terms of ore-to-coal (coke) ratio, voidage distribution and particle size segregation. With different charging patterns, the ore and coal were not distributed uniformly but significant variation. The ore-to-coal (coke) ratio reached a maximum at the radius position of 0.6R where the thickness of ore was significantly larger than that of coal. The voidage distribution along the radial direction shows a U-shape with a minimum at the middle region. In addition, particle size segregation was observed along the radial direction of the burden pile: the smaller particles tended to accumulate in the centre while the larger ones segregated more evidently near the wall. The results showed that the charging pattern was the major factor affecting the burden distribution, followed by burden material type while the burden bed height had a minimum effect.