Carrier flotation of hematite

CIM Bulletin, Vol. 78, No. 883, 1985

IRENE E. CRISTOVEANU and JOHN A. MEECH, Department of Mining Engineering, Queen's University, Kingston, Ontario

The separation of hematite fines (100% -38 pm) from quartz fines (100% -75 /j.m) was investigated using coarse hematite (-212 +150 /j.m) as a carrier in an oleic acid collector system. Oleic acid additions, per cent coarse additions, combined conditioning time and ferric chloride additions were examined. It was found that carrier flotation is a dominant mechanism for fine hematite recovery at oleic acid levels greater than 200 g/t and coarse additions of 10 per cent. Hetero-aggregation is favoured under conditions of lower levels of oleic acid in the presence of ferric chloride and at conditioning times greater than ten minutes. Ferric chloride acts as a depressant for pre-reagentized coarse hematite at oleic acid levels below 150 g/t. At concentration levels above 500 g/t, ferric chloride interferes significantly with the success of carrier flotation of fine hematite. The sensitivity of carrier flotation to changes in oleic acid addition, ratios of fine and coarse material, conditioning time and the presence of an inorganic electrolyte emphasizes that its application is only suitable when flotation conditions can be stabilized.

Mots Clés: Mineral processing, Carrier flotation, Hematite, Comminution, Flotation, Mechanical entrainment, Bubble attachment, Aggregation, Oleic acid.