An Innovative Magnetic Charging Chute to Improve Productivity of Sinter Machine at Rourkela Steel Plant

Abstract

Sintering is a process in sinter machine for agglomeration of iron ore and other raw material fines into a compact porous mass, i.e., sinter, used in Blast Furnaces as an iron bearing input charge material for hot metal production. 'Permeability' of sinter-bed on sinter machine i.e., the porosity in sinter-bed of charged materials, facilitates atmospheric air passes from the top to bottom across the depth of sinter-bed, when suction created from the bottom of the bed, for efficient heat carry over from top to bottom of the bed for complete burning of charged materials for effective sintering process controls the productivity of the sinter machine. The level of 'permeability' in sinter-bed is depending upon the effectiveness of 'charging chute' in size-wise 'segregation' of charge materials across the depth in sinter-bed, achieved due to differences in the sliding velocities of particles during charging into the moving sinter-bed. The permeability achieved by the earlier conventional 'charging chute' was limited due to its design and positional constraints in sinter machine. Improving the productivity of sinter machine, through increased permeability of sinter bed is successfully achieved through implementation of an innovatively designed and developed, "Magnetic Charging Chute" at Sinter Plant no. 2 of Rourkela Steel Plant. The induced magnetic force on the charged materials while the charge materials dropping down through the charge chute has improved the permeability of sinter bed through an unique method of segregating the para-magnetic materials and the finer materials of the charge materials to top layer of sinter bed along with improved size-wise segregation of charge materials. This has increased the productivity of the sinter machine by 3% and also reduced the solid fuel consumption i.e., coke breeze in input charge materials by 1 kg/t of sinter.

Development of Cycloid-Shaped Roll Charging Chute for Sintering Process for Energy Decarbonization and Productivity Improvement in Steel Plants

“…Honorato and Seshadri introduced an intensified sifting feeder (ISF) into the sintering process and demonstrated that it reduces the fractionation of coarse and fine particles, thereby enhancing permeability and increasing productivity [10]. Selvam et al introduced the Magnetic Charging Chute, incorporating magnetic force technology, to enhance the permeability of the feed material [11]. Kim et al developed three forms of charging chutes that can enhance the compaction of charging materials in the sintering process and analyzed them using DEM [6].…”

“…Until recently, several chute designs have been proposed to enhance particle size segregation. These are the intensified sifting feeder (ISF), and magnetic braking feeder (MBF), which were reviewed in prior studies, and most chutes are based on the shape of a straight slope [10,11]. The existing straight slope can change the chute angle by adjusting the angle, but it is difficult to increase the trajectory segregation efficiency because the angles of the upper part where the mixed raw materials enter the chute and the lower part where they leave the chute are dependent on each other.…”