A method for increasing the production rate of iron ore sintering is discussed, and its operational results are reported. The volume of air passing through the raw material bed determines the combustion speed of coke breeze. Therefore, the production rate of a sintering machine depends largely upon the gas permeability of the bed. Gas permeability is affected by particle size segregation in the bed that results from raw material feeding to the sintering machine.
An optimum feeding chute profile for segregation was calculated by assuming that the horizontal velocity of the discharging material is the dominant factor in segregation. The effect of segregation on permeability was also calculated by Ergun's equation. The calculations were experimentally confirmed in a test model with a height equal to that of a fullscale chute but with the width reduced to 1/4.
Actual field operation with the new design showed an increase in the rate of production from 2.1t/(h·m2) to 2.2t/(h·m2), and a 17% reduction in the amount of quick lime required.