Because flash flotation preferentially recovers coarse, liberated particles, some copper is expected to be recovered at this stage. This removal of copper from the regrind circuit may influence both the mass flow rate and the copper grade entering the cleaner circuit. The simulation, therefore, evaluates how these changes affect downstream performance and identifies strategies to mitigate any adverse impacts. 2. Maintaining copper recovery and grade: As copper is the primary revenue driver for Ernest Henry Operations, it is essential that the installation of a flash flotation unit does not negatively affect overall copper recovery or concentrate grade. The simulation assesses potential risks and evaluates operational strategies to minimise any detrimental effects. A summary of the simulation results is presented in Tables 2 and 3. The base case represents the original Ernest Henry Operations circuit configuration prior to the installation of the flash flotation cell and serves as the reference point for comparison with subsequent simulation scenarios. In simulation 1 (Pre_Sim #1), the flash flotation unit (SK240) was incorporated into the reconfigured flowsheet. Simulation 2 (Pre_Sim #2) extended Pre_Sim #1 by applying a froth recovery factor, with the intention of reducing the mass pull in the SK240 cell to help maintain the final copper concentrate grade. Simplified flowsheets illustrating the key streams for the base case and simulations 1 and 2 are shown in Figure 6. Table 2 – Pre-installation simulation results showing gold performance Stream Au (g/t) Au recovery (%) Base Pre_Sim #1 Pre_Sim #2 Base Pre_Sim #1 Pre_Sim #2 Rougher Feed 0.47 0.47 0.47 100 100 100 Rougher Concentrate 10.5 10.5 10.5 52.5 52.5 52.5 SK240 Concentrate - 41.6 76.6 32 32 Cleaner 3 Concentrate 13.5 9.6 9.6 80.9 52.5 52.6 Final Concentrate 13.5 13.5 14.3 80.9 84.5 84.4 Table 3 – Simulation results showing copper performance Stream Cu (%) Cu recovery (%) Base Pre_Sim #1 Pre_Sim #2 Base Pre_Sim #1 Pre_Sim #2 Rougher Feed 0.84 0.84 0.84 100 100 100 Rougher Concentrate 29.0 29.0 29.0 52.5 81.3 81.3 SK240 Concentrate - 13.3 24.1 5.7 5.6 Cleaner 3 Concentrate 28.3 29.1 29.0 95.0 89.4 89.5 Final Concentrate 28.3 27.1 28.6 95.0 95.1 95.1 Figure 6 – Simplified flowsheet used in simulation for (a) base case, and (b) simulation 1 and 2. Cleaner 1 Cleaner 2 Cleaner 3 Final Concentrate Rougher Concentrate Cleaner 3 Concentrate Rougher Feed Cleaner 1 Cleaner 2 Cleaner 3 Final Concentrate Rougher Concentrate SK240 Concentrate Cleaner 3 Concentrate SK240 Rougher Feed
RkJQdWJsaXNoZXIy MTM0Mzk2