Reaserch On Coke Breakage Mechanism In Blast Furnace

Coke, as the main raw material in iron making, has a direct impact on the blast obedient line,the cost of steel and a series of indicators.The charge of coke were increased by the increase of coal powder injection and that brought another problem: coke were stayed a longer time in the wind gap, the carbon loss rate of the coke were increased, the strength of coke was lowered, as the skeleton coke in the blast furnace faced with severe challenges. Air permeability were effected by the increased charge of coke and inevitable damage of coke , Difficulties were leaded in blast furnace operating, even serious accidents were caused, such as hang-ups.The actual strength of coke in the blast furnace has important influence on blast furnace operation. However, due to lack of research method, in particular the lack of after reactive high-temperature coke strength of the measured means, substantial progress is not satisfactory. A continuous hot model of lumpish zone in a blast furnace was used to simulate coke action in blast furnace. The compressive strengths of coke at high temperature with relevant carbon loss rate were measured using a high temperature compressive machine with adjustable atmosphere. The change rules of coke in blast furnace and breakage mechanism were researched.A continuous hot model of lumpish zone in a blast furnace was used to get the relationship between carbon loss rate of coke and temperature in lumpish zone. The limitation of carbon loss rate outside combustion zone was theoretically analyzed. According to the influences of temperature and carbon loss rate, formulas to calculate the real strengths of different kinds of coke in a blast furnace were deduced and the transformation rule of coke strength in blast furnace was discussed. The influences of injection and combustion rates of coal powder on carbon loss rate of coke were analyzed. According to the influence of coal powder injection on coke strength, a method to calculate the suitable combustion rate of coal was given in this paper.