Humphrey's Spiral Tolerance To Feed Variations

CIM Bulletin, Vol. 71, No. 796, 1978

Raymond Dallaire, Associate Professor. Department of Mineral Engineering. Ecole Polytechnique, Montreal, Oue . Andre Laplante, Graduate Student, Department of Metallurgy and Materials Sc ience. University of Toronto , Toronto , Ont., and Jorgen Elbrond, Professor, Department of Mineral Engineering , Ecole Polytechnique, Montreal, Oue .

"The Humphrey's spiral is a static gravity separation device which cannot be adjusted to match short-term variations that occur in the feed. Any disturbance in the feed grade, per cent solids or flow rate affects substantially the recovery and grade of concentrate. Such variations must be minimized in order to maintain the desired rate of production and quality of the product for which the installation has been designed. A study has been performed in which the foregoing assertions were quantified. The feed grade, per cent solids, flow rate and particle size were varied independently. Ore from Carol Lake, Nfld., was used throughout the experiments. This consisted of specular hematite and magnetite in a silica gangue.
Keywords: Metallurgy, Mineral processing, Humphreys spirals, Feed variations, Iron ore, Carol Lake.