Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a, process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: The present invention relates, generally, to a method and apparatus for recovering metal values from a metal-bearing materials, and more specifically, a process for recovering copper and other metals through leaching, electrowinning using the ferrous/ferric anode reaction, and the synergistic addition of ferrous iron to the leach step.

Abstract: The present invention relates, generally, to a method and apparatus for recovering metal values from a metal-bearing materials, and more specifically, a process for recovering copper and other metals through leaching, electrowinning using the ferrous/ferric anode reaction, and the synergistic addition of ferrous iron to the leach step.

Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a, process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: The present invention relates, generally, to a method and apparatus for recovering metal values from a metal-bearing materials, and more specifically, a process for recovering copper and other metals through leaching, electrowinning using the ferrous/ferric anode reaction, and the synergistic addition of ferrous iron to the leach step.

Abstract: The present invention relates generally to a process for removing dissolved or colloidal silica from a pregnant leach solution (“PLS”). More particularly, an exemplary embodiment of the present invention relates to a process which mixes PLS with an acid source, preferably lean electrolyte, to induce formation of colloidal silica that can then be collected and removed. Additionally, in an exemplary embodiment of the present invention, at least one silica seeding agent is added to induce formation of colloidal silica, at least one flocculant is added to induce aggregation of the colloidal silica, and a solid-liquid separation process is utilized to remove advantageous amounts or substantially all of the colloidal silica, thereby providing relief from supersaturation of dissolved silica in the metal recovery processes.

Abstract: An atmospheric leach process in the recovery of nickel and cobalt from lateritic ores, said processing including the steps of: a) separating the lateritic ore into a low magnesium containing ore fraction, and a high magnesium containing ore fraction by selective mining or post mining classification; b) separately slurrying the separated ore fractions; c) leaching the low magnesium containing ore fraction with concentrated sulphuric acid as a primary leach step; and d) introducing the high magnesium content ore slurry following substantial completion of the primary leach step and precipitating iron as goethite or another low sulphate containing form of iron oxide or iron hydroxide, wherein sulphuric acid released during iron precipitation is used to leach the high magnesium ore fraction as a secondary leach step.

Abstract: A process is provided for the leaching of both the “limonite” (Fe approx. ≧25% and Mg approx. ≧6%) and “saprolite” (Fe approx. ≦20% and Mg approx. ≧10%) fractions of typical nickel and cobalt bearing laterite ore. The low magnesium fraction of the laterite ore is leached with sulfuric acid at high pressure and temperature to solubilize the metal values while precipitating most of the solubilized iron as hematite or other iron compounds and a portion of the dissolved aluminum as alunite or other aluminum compounds. After reducing the pressure of the leach slurry to approximately atmospheric pressure, the pregnant leach slurry or solution is contacted with the high magnesium fraction of the ore to solubilize most of the nickel contained in the high-magnesium ore fraction while dissolving only a small portion of the iron content of the high magnesium ore fraction.

Abstract: A process is provided for the leaching of both the “limonite” (Fe approx. ≧25% and Mg approx. ≦6%) and “saprolite” (Fe approx. <20% and Mg approx. ≧10%) fractions of typical nickel and cobalt bearing laterite ore. The low magnesium fraction of the laterite ore is leached with sulfuric acid at high pressure and temperature to solubilize the metal values while precipitating most of the solubilized iron as hematite or other iron compounds and a portion of the dissolved aluminum as alunite or other aluminum compounds. After reducing the pressure of the leach slurry to approximately atmospheric pressure, the pregnant leach slurry or solution is contacted with the high magnesium fraction of the ore to solubilize most of the nickel contained in the high-magnesium ore fraction while dissolving only a small portion of the iron content of the high magnesium ore fraction.