Effect of Mineralogical Characteristic of Jajarm Bauxite Depos it on Its Beneficiation for the propose of Sandy Alumina production in the North West of Northern Khurassan, North East of Iran

摘要

The Jajarm bauxite mine is belonging to the upper Teriassic age. So far this deposit is the largest known bauxite deposit in Iran. Bauxite deposit striking 16 kilometers W-E. This Bauxite underlay the dolomite rocks of Elika Formation and is covered conformability by Shemshak Formation. The study of texture and different phase analysis indicates that the Jajarm Bauxite is typical diasporic bauxite accompanied with Kaolinite as the main reactive silicate minerals and hematite is the only primary iron ore. The main titanium mineral is anatase. Two type of bauxite occurring in Jajarm Bauxite deposit, the first one is the hard bauxite and the other is the shale bauxite or soft bauxite. The Jajarm bauxite varies from dark brown to white cream in color. Al2O3 ranges from 30% to 60% and SiO2 varies between 5% to 39%.The total tonnage of more than 22 million tones and mean value of Al2O3 between47% to 48% and SiO2 around 10%. The Jajarm bauxite shows a politomorphic and micro granular texture with several secondary textural elements. The size of main minerals component are generally below 10 micron, with homogeneous matrix.. In addition, in the very hard bauxite can not do any separation between the crystal grains and the matrix because of similar hardness for both with closely packed space filling and in consequence of the missing defined borderlines of the grains. Based on the above studies Jajarm bauxite can be enriched neither by grain analysis nor by the magnetic separation. Laboratory study shows, only it can be improve by water treatment.