| 摘要 |
<p>The present invention relates generally to processes for mineral extraction and ore processing and more specifically, to processes for recovering iron as a hematite product of high purity from a base metal containing ore material and to processes for recovering base metals from base metal containing materials. A process for recovering iron as hematite from a base metal containing material involves performing a leaching step on the base metal containing material at atmospheric pressure in the absence of an oxidant, using a lixiviant to obtain a solid residue and a leachate containing dissolved iron therein. The lixiviant includes an acid and a chloride. The acid may be selected from the group consisting of an organic acid, sulfurous acid, sulfuric acid and hydrochloric acid. The chloride may be selected from the group consisting of magnesium chloride, calcium chloride, sodium chloride, potassium chloride, ferrous chloride and lithium chloride. Hydrogen sulfide gas formed during the leaching step is stripped from the leachate in a continuous fashion and reacted with sulfur dioxide gas in a Claus reaction to obtain elemental sulfur and steam. Following, separation of the leachate from the solid residue, the leachate may be further treated to recover at least some of the iron as a hematite product of high purity, as well as, the constituent acid and chloride of the lixiviant for reuse in the leach circuit. One of the leachate and the solid residue may thereafterbe subjected to a series of base metal recovery steps and/or value metal recovery steps. The process may be applied to recover iron as hematite and base metals from sulfide ore materials and laterite ore materials.</p> |
