Experimental Study on Burden Descending Behavior in COREX Shaft Furnace with AGD Beams

COREX is an industrially and commercially proven smelting reduction process. It consists of two reactors, the shaft furnace (SF) and the melter gasifier and the SF is placed above the melter gasifier. In the new design of COREX-3000 in Baosteel, China, a new technique called Areal Gas Distribution (AGD) has been adopted. With the installation of two AGD beams, the cross-sectional area varies in a complicated manner which will affect the burden descending behaviour. This work uses a cold model to investigate solid particle behaviour in the SF of COREX-3000. The effect of gas flow, discharging rate and abnormal conditions are characterised in terms of solid flow pattern. The results show that gas flow has a minor effect on burden descending behaviour. Increasing the discharging rate has an effect of reducing the quasi-stagnant zone. A gas channel is observed downstream of AGD beam and the triangle shaped free area increase with the increase of burden discharging rate. For asymmetric flow, particles descend from the top and move to the discharging outlet and a very big stagnant zone is formed on the opposite side of the discharging outlet. The effect of AGD beams on solid flow is evaluated under normal and abnormal conditions. The investigation reveals that the AGD beams affect the solid flow significantly and lead to poor adaptability of furnace to abnormal operations.