Abstract: Suspension roasting test result of oolitic hematite from west part of Hubei province was investigated. The effects of reduction temperature， reduction time， oxidation temperature， particle size on the magnetic properties and phase composition of reduced iron ore were investigated by using vibrating sample magnetometer， X-ray diffraction， Mssbauer spectrometer. The results show that magnetic properties of iron ore enhanced obviously after suspension roasting and directly proportional to the content of strong magnetic iron minerals. Both the magnetization intensity and magnetic susceptibility of reduced ore increased with increase of reduction temperature when reduction temperature range from 550℃ to 650℃. However， when reduction temperature rose to over 700℃， both the magnetization intensity and magnetic susceptibility decreased accordingly. The magnetization intensity and magnetic susceptibility of reduced ore increased with reduction time extending. The content of γ-Fe₂O₃ in roasted ore increased with the increase of oxidation temperature and reached the maximum value when oxidation temperature was at 350℃. When particle size is smaller than 15μm， the magnetization intensity and magnetic susceptibility of particle decreased with the decrease of particle size， while remenance and corecivity of particle increased correspondingly.

Key words: oolitic hematite, suspension roasting, Mssbauer spectrum, magnetization intensity, magnetic susceptibility