IM 2016 November 2016 | Page 23

HEAP LEACH – SX-EW_proof 26/10/2016 10:00 Page 3 HEAP LEACH – SX/EW GoldSim™ software Success can depend on commissioning and ramp-up. Taylor warns against changing “the mine-plan unless supported by test work. If you lower the ore grade, you can’t expect to make the same SX feed copper level. Failure to carry out additional tests will seriously jeopardise plant production and project economics.” Do not skimp on pre-production mining. You may need additional ore in a hurry if problems occur during commissioning and early operation. He also stresses that people must be available “to monitor the leaching performance during commissioning, no matter what. Leaching is your future; so don’t let initial downstream, equipment or infrastructure problems divert your attention. Hire extra people for commissioning if needed – it will be money well spent. “Recalibrate the leaching model with actual data on an ong