Beneflciation Studies of Bama Oxidized Lead and Zinc Ore

Bama is one of the major concentrating plant in Iran which treats nearly 1500 tons per day sulphidic lead and zinc ore. Large amount of oxidized ore exist in Bama which has been extracted along with sulphidic ore. The main objective of the present investigation was the up-grading of the ore from Goshfil which is the major deposit in Bama. The ore contained about 16% zinc as smithsonite, about 1.5% lead as cerussite and about 34.5% iron oxide. Mineralogical studies showed that most zinc and lead minerals could be liberated if the ore ground to minus 75 microns. Pre-concentration methods, such as gravity and magnetic separations, were examined to remove gangue minerals, mainly calcite, dolomite and hematite. The results obtained were not promising. Rotation was extensively applied. Due to low amount of lead in the sample, flotation was not able to concentrate lead minerals. More efforts were made to float zinc minerals. Various cationic and anionic collectors were examined, while it was tried to optimize flotation variables such as pH, collector dosage in each case. At best conditions, the grade of zinc increased to 34.6% with 50.9% recovery and 34.0% with 6 1.5% recovery using amines and fatty acids respectively.