627 • Increased residence time in the rougher banks. • Increased residence time in the Cleaner 1 bank. • Increased mass recovery in the Cleaner 1 bank. • Increased mass recovery in the Cleaner 3 bank. • Redirection of Cleaner 1 Bank 1 concentrate to the head of Cleaner 3. • Redirection of Cleaner 1 Bank 1 concentrate to the head of Cleaner 3, combined with increased mass pull in the Cleaner 1 bank. • Redirection of Cleaner 1 Bank 1 concentrate to the head of Cleaner 3, combined with increased residence time in the Cleaner 1 bank. • Increased mass pull in the SK240 flash flotation cell. • Increased mass pulls in both the SK240 cell and the Cleaner 1 bank. The simulated gold and copper recoveries for each scenario are presented in Figure 6, which illustrates the step change in recovery relative to the original base‑case performance. Figure 6 – Simulated recovery results for gold (left) and copper (right) using JKSimFloat Increasing residence time is expected to improve gold and copper recoveries (Simulations 1, 2, and 7). However, achieving these gains would require additional flotation capacity, meaning an economic assessment is necessary to justify the associated capital and operating costs. In this case, the projected benefit may not be sufficient to warrant proceeding with the investment. Increasing mass pull in the SkimAir® SK240 is predicted to improve gold recovery by 1.6% (Simulation 8). In practice, this can be achieved by operating the SK240 at a shallower froth depth. Although the simulation suggests only a minor reduction in copper concentrate grade, operating at shallow froth depth may significantly increase pyrite recovery to the SK240 concentrate, potentially diluting the final product quality. A carefully designed experimental trial is recommended to identify operating conditions that maximise gold recovery while minimising any adverse impact on copper concentrate quality. 6. ONGOING AND FUTURE OPTIMISATION INITIATIVES Following installation and commissioning of the SK240 flash flotation cell, several optimisation programs were undertaken to improve both cell performance and overall circuit outcomes based on the simulations performed above. 6.1 Mass pull optimisation Results from the JKSimFloat simulation indicated potential to increase gold recovery through more aggressive mass pull across the SK240 cell. Given the possible implications for the downstream circuit— particularly the cleaner circuit—the final copper concentrate was closely monitored to assess any impact on overall circuit performance. One clear effect observed during the trial was a reduction in feed grade and mass flow to the cleaner circuit. To maintain final concentrate grade targets under these conditions, it became necessary to slow the
RkJQdWJsaXNoZXIy MTM0Mzk2