Bastin, David[Université de Liège - ULg > Département Argenco : Secteur GeMMe > Génie minéral et recyclage >]
Proceedings of the Iron Ore 2011 International Conference
978 1 921522 43 7
Iron Ore 2011, International Conference, Perth 11-13 july, 2011
11-13 July, 2011
Australian Institute of Mining and Metallurgy
[en] dephosphorisation ; iron ore ; minerals
[en] The oolitic iron ore reserves in Lisakovsky, Northwest Kazakhstan represent a quite challenging deposit both from technological and from resource point of view. The difficulties in processing such type of ore are connected with the extremely fine dissemination of phosphorus and gangue minerals inside the oolitic formations. The goethite crystals are cemented in their structure by aluminosilicates with quartz and other gangue minerals and dissemination is so fine that they are not separable by physical methods. The laboratory tests performed in direction of dephosphorisation have shown that the combination of alkaline roasting followed by low intensity magnetic separation and acid leaching enables the obtaining of high grade iron concentrate. The magnetic separation performed ahead of leaching has been efficient by means of buffering the high pH via washing out the soluble salts and the excess of bases and applied after leaching has facilitated the removal of secondary liberated gangue minerals in the non-magnetic fraction. As a consequence, phosphorous content has been dropped to a more acceptable for the ferrous metallurgy levels while iron grade and recovery have reached respectively 61.6 and 80.8 percent.