| 摘要 |
<p>A hydrometallurgical method (10) for the extraction of nickel and cobalt from laterite ores, the method characterised by the method steps of: (i) Beneficiating (14, 16) a run of mine laterite ore containing nickel and cobalt into a substantially fine ore fraction and a substantially coarse ore fraction; (ii) Passing the fine ore fraction to a pressure acid leaching step (26) in which a sulphuric acid lixiviant is used to extract nickel and cobalt values forming a leach slurry comprising liquor and residue solids components; (iii) Passing at least a portion of the coarse ore fraction to an agglomeration step (22) in which the coarse ore fraction is agglomerated; (iv) Forming at least one heap (40, 48) from the agglomerated ore of step (iii); (v) Passing the leach slurry from the pressure acid leach step (ii) to a solid/liquid separation step (28), from which the residue solids are passed to waste (30), a proportion of the liquor is passed to further processing for metals recovery (34) and a further portion of the liquor is passed directly or indirectly to the or each heap (40, 48) formed in step (iv); (vi) Leaching the coarse ore fraction in the heaps (40, 48) with liquor separated in step (v) wherein the leaching agent is the free acid remaining therein from the pressure acid leaching step (ii); and (vii) Passing pregnant leach solution from the or each heap (40, 48) to metals recovery (34).</p> |
