Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the step of processing a metal sulfide concentrate in a reductive activation circuit 220 that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate. The method may further comprise the step of subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit 240 to extract metal values. In some disclosed embodiments, reductive activation steps and/or oxidative dissolution steps may employ mechano-chemical and/or physico-chemical processing of particles or agglomerates thereof. Reductive activation may be made prior to heap leaching or bio-leaching operations to improve metal extraction. Systems for practicing the aforementioned methods are also disclosed.

Abstract: Systems for improving metal leach kinetics and metal recovery during atmospheric or substantially atmospheric leaching of a metal sulfide are disclosed. In some embodiments, an oxidative leach circuit 200 may employ Mechano-Chemcial/Physico-Chemical processing means for improving leach kinetics and/or metal recovery. In preferred embodiments, the Mechano-Chemcial/Physico-Chemical means comprises various combinations of stirred-tank reactors 202 and shear-tank reactors 212. As will be described herein, the stirred-tank reactors 202 and shear-tank reactors 212 may be arranged in series and/or in parallel with each other, without limitation. In some non-limiting embodiments, a shear-tank reactor 212 may also be disposed, in-situ, within a stirred-tank reactor 202.

Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the step of processing a metal sulfide concentrate in a reductive activation circuit 220 that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate. The method may further comprise the step of subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit 240 to extract metal values. In some disclosed embodiments, reductive activation steps and/or oxidative dissolution steps may employ mechano-chemical and/or physico-chemical processing of particles or agglomerates thereof. Reductive activation may be made prior to heap leaching or bio-leaching operations to improve metal extraction. Systems for practicing the aforementioned methods are also disclosed.

Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the step of processing a metal sulfide concentrate in a reductive activation circuit 220 that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate. The method may further comprise the step of subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit 240 to extract metal values. In some disclosed embodiments, reductive activation steps and/or oxidative dissolution steps may employ mechano-chemical and/or physico-chemical processing of particles or agglomerates thereof. Reductive activation may be made prior to heap leaching or bio-leaching operations to improve metal extraction. Systems for practicing the aforementioned methods are also disclosed.

Abstract: A method of controlling iron in a hydrometallurgical process is disclosed. The method may comprise the steps of: leaching (14, 114) a feed slurry (2, 102); forming a pregnant leach solution (12a, 12b; 112a, 112b); removing a first leach residue (18, 118) from the pregnant leach solution (12a, 12b); and sending a portion (12b, 112b) of the pregnant leach solution (12a, 12b) and/or raffinate (22, 122) produced therefrom, to an iron removal process (34, 134). According to some preferred embodiments, the iron removal process (34, 134) may comprise the steps of: sequentially processing the pregnant leach solution (12a, 12b) and/or raffinate (22, 122) produced therefrom in a first reactor (R1) a second reactor (R2), and a third reactor (R3); maintaining a pH level of the first reactor (R1) above 4, by virtue of the addition of a first base; maintaining a pH level of the second (R2) and/or third (R3) reactors above 8.5, by virtue of a second base; and forming solids (46) comprising magnetite (68).

Abstract: A method of controlling iron in a hydrometallurgical process is disclosed. The method may comprise the steps of: leaching (14, 114) a feed slurry (2, 102); forming a pregnant leach solution (12a, 12b; 112a, 112b); removing a first leach residue (18, 118) from the pregnant leach solution (12a, 12b); and sending a portion (12b, 112b) of the pregnant leach solution (12a, 12b) and/or raffinate (22, 122) produced therefrom, to an iron removal process (34, 134). According to some preferred embodiments, the iron removal process (34, 134) may comprise the steps of: sequentially processing the pregnant leach solution (12a, 12b) and/or raffinate (22, 122) produced therefrom in a first reactor (R1) a second reactor (R2), and a third reactor (R3); maintaining a pH level of the first reactor (R1) above 4, by virtue of the addition of a first base; maintaining a pH level of the second (R2) and/or third (R3) reactors above 8.5, by virtue of a second base; and forming solids (46) comprising magnetite (68).

Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the steps of: (a) producing a metal sulfide flotation concentrate; (b) processing the metal sulfide concentrate in a reductive activation circuit that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate; and, (c) subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit to extract metal values. In some disclosed embodiments, reductive activation steps may be employed prior to oxidative leaching steps (including heap leap leaching or bio-leaching steps). In some embodiments, physico-chemical processing steps may be employed during reductive activation and/or oxidative leaching. Systems for practicing the aforementioned methods are also disclosed.

Abstract: A method of controlling frothing during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the steps of (a) producing a metal sulfide concentrate via flotation; (b) producing a tailings stream via flotation; and, (c) diverting a portion or all of said produced tailings stream to an atmospheric or substantially atmospheric sulfide leach circuit. A metal recovery flowsheet is also disclosed. In some embodiments, the metal recovery flowsheet may comprise a unit operation comprising: (a) a sulfide concentrator comprising a flotation circuit, the flotation circuit producing a metal sulfide concentrate stream, and a tailings stream; and, (b) an atmospheric or substantially atmospheric metal sulfide leach circuit. The sulfide concentrator may be operatively connected to the atmospheric or substantially atmospheric metal sulfide leach circuit via both of said metal sulfide concentrate stream, and said tailings stream.

Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the step of processing a metal sulfide concentrate in a reductive activation circuit 220 that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate. The method may further comprise the step of subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit 240 to extract metal values. In some disclosed embodiments, reductive activation steps and/or oxidative dissolution steps may employ mechano-chemical and/or physico-chemical processing of particles or agglomerates thereof. Reductive activation may be made prior to heap leaching or bio-leaching operations to improve metal extraction. Systems for practicing the aforementioned methods are also disclosed.

Abstract: A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the steps of: (a) producing a metal sulfide flotation concentrate; (b) processing the metal sulfide concentrate in a reductive activation circuit that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate; and, (c) subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit to extract metal values. In some disclosed embodiments, reductive activation steps may be employed prior to oxidative leaching steps (including heap leap leaching or bio-leaching steps). In some embodiments, physico-chemical processing steps may be employed during reductive activation and/or oxidative leaching. Systems for practicing the aforementioned methods are also disclosed.

Abstract: A method of controlling frothing during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the steps of (a) producing a metal sulfide concentrate via flotation; (b) producing a tailings stream via flotation; and, (c) diverting a portion or all of said produced tailings stream to an atmospheric or substantially atmospheric sulfide leach circuit. A metal recovery flowsheet is also disclosed. In some embodiments, the metal recovery flowsheet may comprise a unit operation comprising: (a) a sulfide concentrator comprising a flotation circuit, the flotation circuit producing a metal sulfide concentrate stream, and a tailings stream; and, (b) an atmospheric or substantially atmospheric metal sulfide leach circuit. The sulfide concentrator may be operatively connected to the atmospheric or substantially atmospheric metal sulfide leach circuit via both of said metal sulfide concentrate stream, and said tailings stream.

Abstract: A mixer settler system is disclosed. The system comprises a mixer [110] configured for receiving an organic phase and an aqueous phase, the mixer [110] being further configured to maintain the organic phase and the aqueous phase in a single unstable emulsion phase, wherein mass transfer occurs between said organic phase and said aqueous phase; and, a column settler [120] which is configured to receive a single unstable emulsion phase from the mixer [110] via an emulsion inlet [125] and is also configured to separate the single unstable emulsion phase into a stable organic phase and a stable aqueous phase by virtue of coalescence; the column settler further comprising an organic outlet [121] above the emulsion inlet [125] and an aqueous outlet [123] below the emulsion inlet [125]; the column settler [120] further discouraging mass transfers within the unstable emulsion phase and further promoting coalescence of each of said stable organic phase and stable aqueous phase.

Abstract: A sludge or slurry physical stabilizing method combines coarse particles with a slurry of fine particles to generate a composite slurry having a substantially predetermined ratio of coarse particles to fine particles. The composite slurry can then be diluted, flocculated and dewatered. Superabsorbent polymer (SAP) is mixed in with the dewatered composite slurry in an amount effective to produce a somewhat friable, semi-solid conveyable composition of sufficient strength to enable transport, stacking and support of restored overburden at a mining site.

Abstract: A system and process are provided for recovering copper from a contaminated copper-bearing source such as copper smelter flue dust. The copper-bearing source is leached in an acidic solution to produce a liquor containing dissolved copper and dissolved contaminants. Simple copper sulfides are precipitated from the liquor by reacting the liquor with chalcopyrite and sulfur dioxide. Copper is recovered from the precipitated sulfides.A novel process is provided for precipitating simple copper sulfides from a solution containing both dissolved copper and dissolved contaminants. The solution is combined with precipitation product such that substantially all ferric iron contained in the solution is reduced to ferrous iron. The ferric-free solution is reacted with chalcopyrite solids and sulfur dioxide to precipitate the dissolved copper as simple copper sulfides.

Abstract: A system and process are provided for recovering copper from a contaminated copper-bearing source such as copper smelter flue dust. The copper-bearing source is leached in an acidic solution to produce a liquor containing dissolved copper and dissolved contaminants. Simple copper sulfides are precipitated from the liquor by reacting the liquor with chalcopyrite and sulfur dioxide. Copper is recovered from the precipitated sulfides.A novel process is provided for precipitating simple copper sulfides from a solution containing both dissolved copper and dissolved contaminants. The solution is combined with precipitation product such that substantially all ferric iron contained in the solution is reduced to ferrous iron. The ferric-free solution is reacted with chalcopyrite solids and sulfur dioxide to precipitate the dissolved copper as simple copper sulfides.

Abstract: A slurry electrowinning apparatus includes a tank (10) in which are mounted alternating, spaced-apart anode (18) and cathode (20) electrodes. An inlet opening (60) is formed in a side of the tank (10) for introducing a copper-bearing electrolyte to the tank (10). An overflow opening (76) is also formed in a side of the tank (10) such that a solution level (62) is maintained in the tank (10) which is above the inlet opening (60). Baffles (64) are mounted within the tank (10) for evenly distributing the slurry within the tank (10) between the anodes (18) and cathodes (20). Both the anodes (18) and the cathodes (20) are supported within the tank (10) by electrode guides (22) such that a high pressure contact between the electrodes (18, 20) and the main electrical bussing (78) is provided.

Abstract: A process and system are provided for recovering copper from chalcopyrite concentrate. The chalcopyrite is ground to a mean particle size of about 1.5-5 microns. The ground chalcopyrite is then divided into a first stream and a second stream. The first stream is leached in a leach solution containing at least about 100 gpl sulfuric acid and about 10-30 gpl ferric iron to produce a copper sulfate solution containing about 40-75 gpl dissolved copper and less than about 5 gpl ferric iron. The second stream of ground chalcopyrite is combined with the copper sulfate solution and with sulfur dioxide such that the combination reacts to precipitate dissolved copper from the copper sulfate solution as simple copper sulfides and to produce a liquor containing dissolved ferrous iron. The simple copper sulfides are then separated from the ferrous iron liquor.

Abstract: Apparatus for continuous electrowinning of copper bearing slurries, including an electrowinning cell wherein a slurry composed of a suitable electrolyte and a copper-bearing solid material, is subjected to the simultaneous reactions of dissolving the copper material and plating out elemental copper as a relatively pure copper product. The apparatus and process also includes means to purify the copper-bearing material before passage to the electrowinning cell so as to prevent contamination of the electrolyte in the cell and, also, a means to recover sulfur which is released during the electrowinning and unreacted copper material.

Abstract: Apparatus and process for continuous electrowinning of copper bearing slurries, including an electrowinning cell wherein a slurry composed of a suitable electrolyte and a copper-bearing solid material, is subjected to the simultaneous reactions of dissolving the copper material and plating out elemental copper as a relatively pure copper product. The apparatus and process also includes means to purify the copper-bearing material before passage to the electrowinning cell so as to prevent contamination of the electrolyte in the cell and, also, a means to recover sulfur which is released during the electrowinning and unreacted copper material.