PERTH (miningweekly.com) – An updated prefeasibility study (PFS) into the Caravel copper project, in Western Australia, has reduced capital cost estimates, the operating costs, and the water and energy demands from the July PFS.
The updated PFS reconfigured the two-train flotation circuit which was presented in the July PFS into a single train 27-million-tonne-a-year throughput plant, which simplified construction, enhanced operability and improved both capital and operating costs, said ASX-listed Caravel Minerals on Tuesday.
The original PFS estimated that the project could produce 62 000 t/y of copper at a C1 cost of some $1.72/lb. The study estimated that the capital cost for the dual train plant would be A$1.2-billion, based on the development of two 13.9-million-tonne-a-year-capacity trains.
The updated PFS, which also included coarse particle flotation in the process flowsheet, and the use of high-pressure grinding rolls, has now reduced the processing cash unit costs by up to A$1.23/t of ore, reduced the capital costs by around A$100-million, reduced the C1 costs from $1.72/lb to $1.54/lb and reduced all-in sustaining costs from $2.55/lb to $2.37/lb.
Furthermore, the changes have has also reduced installed power demand by up to 22 MW and reduced water consumption by about 1.8 Gl/y.
Annual copper-in-concentrate production would be slightly lowered from 62 000 t/y to 60 000 t/y on the back of the proposed changes.
However the updated PFS has also resulted in an increase to the estimated pre-tax net present value from the A$1.06-billion estimated in the original study, to between A$1.3-billion to A$1.7-billion, while the internal rate of return has increased from the previously estimated 14.7% to between 16% and 20%.