Melting Property of MgO Containing Sinter

Reaction Behavior of Dolomite Accompanied with Formation of Magnetite Solid Solution in Iron Ore Sintering Process

“…A rim structure of magnetite s.s, which was denser than that in dolomite assimilation, was observed. As reported in the previous work 16) and other papers, 6,13,17) slag was observed between relict serpentine and the rim structure of magnetite s.s. The diffusion of MgO was restricted from the rim structure, resulted in 'hematiteϩslag' without formation of magnetite s.s. at the outer matrix structure.…”

“…Figure 9 shows schematic explanation of dolomite assimilation and microstructural evolution during sintering together with those of serpentine as mentioned after. 6) explained that CaO dissolves into calciumferrite melt, and then MgO reacts with calciumferrite melt to form di-calciumferrite. On the other hand, Loo et al 14) claimed that magnetite s.s formed as a result of solid-solid reaction between hematite and MgO as the first step, subsequently solid di-calciumferrite was formed by a reaction between CaO and magnetite s.s.…”

“…Nevertheless investigations focusing on evaluation of dolomite as MgO source and comparison with other MgO-bearing fluxes such as serpentine, olivine, dunite or Ni-slag are limited. [6][7][8][9][10][11] Most of them reported the decrease of yield and/or strength with replacement of 'serpentine/dunite and limestone' by 'dolomite and quartz' in the constant chemical compositions of sinter. With regards to the influence of dolomite on reduction behavior of sinter, Matsumura et al 11) found that reduction behavior of sinter with high MgO content and low SiO 2 using dolomite was superior to that using serpentine even in the constant conditions of chemical composition and bonding agent.…”

Recent advances in iron ore sintering

“…However, such a system requires more than one charging unit for a single sintering machine. Therefore, systems such as the Segregation Feeder (SF) (Sasaki et al 1980), slit bars (Fukuda et al 1984, Inazumi 2000, slit wires (Takai et al 1993), and the Intensified Sifting Feeder (ISF) (Honorato and Seshadri 2008) have subsequently been developed to enhance segregation. Figure 7 shows schematic diagrams depicting the size segregation achieved by some of these charging methods.…”

“…However, with conventional drum charging systems, only limited segregation can be achieved due to the natural feed flow. An air nozzle to blow air at the point of raw material mix departing from the sloping chute was found to be efficient for achieving particle size and coke segregation due to the density differences (Sasaki, Suga, and Fukuda 1980). To enhance the segregation degree, some sinter machines have tried multiple layer charging methods.…”