关键词: 赤铁精矿, 铁尾矿, 膨润土, 造球, 成球性, 落下强度, 抗压强度, 爆裂温度

Abstract: The effects of content and properties of raw materials and pelletizing parameters on properties of green pellet were studied in order to determine the appropriate technology parameters for pelletizing of a Brazilian Carajas hematite concentrate with Fe grade of 67.45%,SiO₂ content of 2.54%, particle size of 95.72% passing -0.045 mm and specific surface area of 1 647 cm²/g as main raw material, the hematite tailings from Shanxi with Fe grade of 14.38%, SiO₂ content of 67.22%,particle size of 87.27% passing 0.045 mm and specific surface area of 1 698.85 cm²/g produced from high intensity magnetic separation as silicon agents, bentonite with water absorption rate of 436.01%, montmorillonite content of 62.22% and particle size of 99.4% 0.074 mm used as binder, with drop strength, compressive intensity, and burst temperature of green pellet as evaluating index. The result showed that the optimum conditions for pelletizing were hematite concentrate specific surface area of of 1 768 cm²/g, bentonite dosage of 0.8%, ratio of tailings to hematite concentrate of 2.2%, moisture content of hematite concentrate at 8.0%, moisture content of green pellet at 10.0% during pelletizing, pelletizing for 12 minutes, revolving speed of the plate at 22 r/min, and the corresponding dropping strength and compressive strength were 6.8 times and 14.15 N respectively with critical burst temperature of 427 ℃.

Key words: Hematite concentrate, Iron tailings, Bentonite, Pelletizing, Sphericity forming, Drop strength, Compressive strength, Burst temperature