Complete Absense of Any Acidic Leach TailingsThe more I think about a small leach plant at Decar the more things I find to like about it.
The Cobalt 27 article I posted earlier makes it completely clear that acid tailings are the biggest problem with HPAL. Coincidentally, it is the problem of acidic tailings reduction that Direct Nickel ("DNi") claims to be addressing with their recycled nitric acid process.
No such problems would exist at a Decar leach plant. The very small amount of tailings would be mostly hematite (Fe2O3 iron ore) from precipitation and Counter Current Decantation ("CCD"). And this could simply be mixed in with the much larger stream of magnetite (Fe3O4 iron ore) by-products and shipped away by rail to be made into steel somewhere else. The slight PH decrease of the blended iron ore by-product should make no difference at all when it is subsequently melted.