E. G. CRAYSTON; L. H. VAN LOONt; A. F. HEATHER
Madsen's problem of securing a source of backfill material is solved by the treatment of mill tailings in DorrClones. These machines are cylindro- conical classification units utilizing centrifugal force in place of gravity and were developed by the Dutch State Mines, Limburg, The Netherlands, in 1939 for use in coal washing. Currently 45 per cent of the tonnage milled is made available in a suitable condition to be sent underground as backfill.
boreholes, microns, pipe, pulp, tailings, Materials, Mill, Mills, Mine, Mines, Pipe, Underground, Waters