Location and extent of cohesive zone in the blast furnace as related to the degree of reduction of iron ore pellets/iron ore

Abstract

In addition to the chemistry, the degree of reduction of the iron bearing materials in the burden affects the characteristic temperature of the resulting primary slag in the cohesive zone of the Blast Furnace. Thus the location and extent of the cohesive zone which acts as a gas-distributor in the blast furnace are both influenced by the degree of reduction the iron bearing material undergo prior to their entry into the cohesive zone travelling through the granular zone. The present work is involved with sintering the iron-bearing materials, namely fluxed pellets and raw ore, to different degree of reduction and determination of the characteristic of these pre-reduced materials. The softening temperature of the fluxed pellet increases with the increase of the degree of reduction up to 65% and then shows a reverse trend. In case of raw-ore the corresponding value is recorded to be 70%. Thus the cohesive zone supposed to be lowered with the increase in reduction of the fluxed-pellets, up to 65% reduction and similar trend is observed up to 70% for raw-ores. Due to certain experimental ambiguity the flow characteristic the flow-temperature, the softening-flow interval and thus the extent of the cohesive zone, as a function of the reduction of the iron bearing materials, is so difficult to be as curtained very accurately and only a likely trend has been reported.