Inhomogeneous vertical sintering of a sintering feed bed for vanadium-titanium magnetite

Changes in temperature of vanadium-titanium magnetite sintering feed at different depths during mineralization processes were studied by measuring the temperature values of different sintering layers.Two quantitative parameters,flame front speed and mineralization front speed,were defined to evaluate the inhomogeneous degree of vertical sintering.The results show that the flame front speed and mineralization front speed decrease with increasing layer depth,indicating that there is a serious structural change in the lower region of the sintering feed bed and the sintering permeability deteriorates.Promoting the charge segregation and increasing the mean diameter and thermal intensity of quasi-particles in the lower region of the sintering feed bed are of great importance for enhancing the sinter productivity.Simultaneously,mineralogical analysis of sinters at different sintering layers show that the vanadium-titanium magnetite sinter ore consists of magnetite,hematite,calcium ferrite,dicalcium silicate,perovskite,and vitreous mineral.With the layer depth increasing,the contents of magnetite,dicalcium silicate and perovskite increase,while the contents of hematite and calcium ferrite decrease.