Preparation of Hydraulic Sand and Cement Backfill at Noranda Mines Limited (Geco Division)

"A description of the Geco orebody has been given by W .L. Brown and R.C.E. Bray (1). The mill flowsheet and equipment were described by M.J.S. Bennett, D. Wild and C. Lawton (2). Mill capacity is now 4, 150 tons per operating day of copper, silver, zinc and lead ore. A recent flowsheet has been published in the - Canadian Mining Manual (1966).Soon after the start of production in September 1957, it became apparent that large tonnages of sand would be required by the mine for backfill pruposes. Initial experimental work on the preparation of sand fill from the flotation tailings was begun in late 19 59. Cyclones of local manufacture, in a variety of sizes, were tested quite successfully. There were, however, several obvious advantages with some of the custom-built cyclones and a recommendation was obtained from the Techniquip Company. A single Krebs D-10-B cyclone was tested experimentally in 1960.INITIAL TESTWORKExperimental results showed that with our relatively coarse grind (in the order of 53 % minus 200 mesh) 75 - 80% of the flotation tailings could be recovered as backfill sand with one stage of treatment. Percolation rates of four inches per hour were obtained with cyclone inlet pressures in the range of 20 - 25 psi and feed densities of 20 - 23% solids."