METHOD FOR CONTROLLING ROTATING SPEED OF ROTARY FURNACE HEARTH IN REDUCED IRON PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a method for suitably controlling rotating speed of a furnace hearth by judging the completing point of reduction reaction at high accuracy at the time of producing reduced iron. ;SOLUTION: At the time of producing the reduced iron by charging mixed material of powdery iron material and powdery solid reducing agent and burning, CO and CO₂ concns. in the atmospheric gas near the discharging part of the burnt reduced iron are continuously measured, and the rotary speed of the furnace hearth is controlled so that CO/CO₂ or CO/(CO+CO₂) becomes a prefixed value, or CO and CO₂ concns. are measured as the same way in plural positions along the shifting direction of the furnace hearth near the discharging part so that the difference of CO/CO₂ or the difference of CO/(CO+CO₂ between each measured position become prefixed value. Dust concn. contained in the same atmospheric gas is continuously measured and the rotating speed of the furnace hearth may be controlled so that the dust concn. becomes the prefixed value.;COPYRIGHT: (C)1999,JPO