Russian Paper On Leaching Converter Mattehttps://link.springer.com/article/10.1134/S0036029510120062 This example is a bit different from the Lonmin Marikana example I posted last month, in that it leaches only the magnetic fraction of the converter matte. This Norilsk matte also seems a bit more complex, containing various sulfide components. Grind size was 150-200 micron, compared to the 25 micron regrind in the latest FPX flowsheet.
Bottom line is that they achieved good leach results, at 90 degC (no pressure) and it does not seem like they used oxygen enrichment. The only impediment seems to be the copper-nickel alloy, which is not present in FPX concentrate.
I am pretty ticked off that the share price has still not reacted to the latest PR, which I consider to be very positive for several reasons. So, I keeping looking for something that I might have missed but I cannot find anything wrong. My prediction remains the same: When the lab finishes the rest of the metallurgy study, it will be clear that there is a straight forward path to battery chemicals (likely including some cobalt sulfate), at a low additional Capex.
How this factors in to the PEA revision is less clear. A leach plant with battery chemical production might require a separate PEA, using input costs at whatever level of payability is used for the concentrate. Assuming 95% payability for the nickel concentrate, manufacturing it into battery chemicals shouild capture the remaining 5% plus another $1.50 per pound premium. Although it might be wise to use only $1.00 per pound premium, as Mark Selby has suggested that this margin will begin to erode as more battery chemical production comes on line.
A back of the napkin calculation gives 150,000 TPD mining --> 70,000 TPA nickel --> 154 M pounds of nickel per year @ 1.00 premium = $154,000,000 / year less costs. This should support $200M in CAPEX with a 2 year payback. Leaching capacity requirements will be not too much more than starting from Class 1 nickel.