Caravel Minerals Limited announced that the Caravel Copper Project Pre-Feasibility Study (PFS) Update ­ Single Train Option Study outlined the adoption of a single train design using High Pressure Grinding Rolls (HPGRs) in the processing plant's primary grinding circuit, replacing Semi-Autogenous Grinding (SAG) mills originally selected in the PFS released on 12 July 2022. Further testwork has now been completed, better defining the assumptions used for the HPGR performance and specifications. A 2 tonne bulk sample from the Bindi East and Hinge Zone starter pits was sent for HPGR testing at the Bureau
Veritas Mineral Laboratory in Perth, Western Australia. The work was conducted using an Enduron® test unit with a roll diameter of 0.80m and 0.25m wide. A total of 6 ests were performed to determine grinding performance, energy use, wear rates, and design parameters for commercial scale application. The tests achieved the expected size reduction from ~30mm to ~8mm, under an operating pressure of 3N/mm2 while consuming 1.6 kWh/t and operating at a nominal throughput rate of 265t/hr-m3. The positive results confirm the PFS assumptions which are typical for copper ores and confirm HPGR's can achieve Caravel's processing plant throughput of 27mtpa. Two HPGRs will be incorporated into the overall crushing and grinding circuit, consisting of a primary gyratory crusher, secondary cone crushers, HPGRs and ball mills. The project is evaluating the merits of selecting industry proven HPGRs sized at 2.4m diameter, each with 8MW drives. Additional tests are underway to optimise the energy usage across the HPGR crushing ball mill grinding circuit. Power management is an increasingly important opportunity for grid connected facilities that seek to maximise their utilisation
of renewable energy and reduce exposure to short duration price peaks.