Influence of Coke Breeze Positioning on the Sintering Behavior of Pellets and Raw Material Bed with Embedded Pellets

Abstract

緒言近年，鉄鉱石資源は，AlWith increasing the coke breeze ratio in the green pellet made from ore and coke mixture fine of -125μm, the tensile strength of the green and dried pellets decreased. Based on the evaluations under the green and dried pellet equations concerning particle bond, it was presumed these results were caused by the decrease in the contact points between particles due to the reduction of mixture fine's specific surface area. With increasing the coke breeze ratio in the nucleus pellet, the tensile strength of the fired pellets also decreased. From the change in the porosity up to 900°C, sintering was predominant to the tensile strength. In the temperature from 900°C to 1200°C, the increase of strength became small by adding coke breeze in the nucleus pellet. It was presumed this result was caused by remarkable increase of void after coke combustion.In the sintering of raw material bed with embedded the coke breeze coating pellet, the surrounding temperature of pellet increased and the large void was generated under the pellet. Based on the 2-dimensional numeric evaluation, it was found the heat amounts of the pellet and gas heated by coke combustion were transported to the area under the pellet where the gas flow rate was low. It was presumed this heat concentration caused the remarkable melting and large void formation.

Effect of Coke Breeze Distribution on Coke Combustion Rate of the Quasi-particle

“…Hiroshi OGI, 1) * Takayuki MAEDA, 2) Ko-ichiro OHNO 2) and Kazuya KUNITOMO 2) plification of experimental condition, alumina powder was prepared as the substitute of iron ore. It can make to ignore the effects of melt formation, reduction and re-oxidation of iron ore on the coke combustion.…”

Development of Control Techniques for Mixing Small Coke at Bell-less Top Blast Furnace

“…[15][16][17] Where future raw material quality is concerned, high quality iron ore has been largely depleted, and atomization, high SiO 2 , and high Al 2 O 3 of iron ore are predicted. [18][19][20] Although sintering machine operation will be adjusted to cope with declining raw material quality, decreased raw material reducibility, increased slag rate, and similar problems are considered at the blast furnace. Similarly, decreases in the particle size and strength of the coke are predicted against the background of depletion of caking coal, which is indispensable to the manufacture of good quality coke, 21,22) and deterioration of coke ovens with age.…”