Abstract: In order to provide a reference for studying how to improve ultrafine grinding efficiency of high phosphorus oolitic hematite in western Hubei province, the influences of ore fineness, pulp density, pulp temperature and shear rate to the viscosity of high phosphorus oolitic hematite were investigated. The results showed that the slurry viscosity of high phosphorus oolitic hematite increased with the concentration of the slurry raised and mineral particle fining exponentially. For the coarse ore, the temperature had less effect on the slurry viscosity; For the fine ore, the slurry viscosity declined linearly with temperature gradually increased. As the shear rate increased, the slurry viscosity fell and dropped greatly at the early stages of shear rate decrease. The test results indicated that when the high phosphorus oolitic hematite was ground to be ultra-fine, it is not suitable for exceeding to 50% for the slurry concentration. Meanwhile appropriate increase of the grinding speed will help to reduce the slurry viscosity and improve grinding efficiency.

Key words: High phosphorus oolitic hematite of Western Hubei, Pulp viscosity, Ore fineness, Pulp concentration, Pulp temperature, Shear rate