Abstract: Methods for recovering a metal value from a metal-bearing material are provided. The method comprises agglomerating the metal-bearing material with an agglomeration solution comprising a raffinate, an oxidant, and citric acid or salts thereof to form an agglomerated metal-bearing material; leaching the agglomerated metal-bearing material with a leaching solution comprising the raffinate and the citric acid or salts thereof to produce a pregnant leaching solution and a leached material; re-oxidizing the leached material with a curing solution comprising the raffinate and the oxidant; and recovering the metal value from the pregnant leach solution to produce the raffinate.

Abstract: The present disclosure is directed to systems and methods for tree preservation planning of a selected tree within an existing landscape including hardscape elements. The critical root loss percentage can be determined based upon the diameter size of each tree being impacted. In addition, the disclosure provides a system for determining survivability of an impacted tree that takes into account a number of factors to ensure a survivability percentage of at least 70%.

Abstract: A method is provided for recovering scandium values from scandium-bearing ores. The method includes providing a scandium-bearing ore; subjecting the scandium-bearing ore to atmospheric pressure acid leaching with sulfuric acid, thereby producing a first, scandium-bearing solution containing ferric (Fe3+) ions; subjecting the first solution to hydrothermal processing, thereby precipitating from the first solution a material selected from the group consisting of hematite and basic iron sulfates and generating a second, scandium-bearing solution; and recovering scandium values from the second solution.

Abstract: Methods are provided for the recovery of scandium from scandium-bearing ores. The methods included leaching under atmospheric conditions using various acids. Solution impurities are removed from the leachate and scandium values are then recovered from the leachate.

Abstract: Processes for recycling printed wire boards using environmentally-friendly compositions, wherein electronic components, precious metals and base metals may be collected for reuse and recycling.

Abstract: A heap of a material to be leached to recover a valuable metal from the material and a method of constructing the heap are disclosed. The heap comprises sides and a top and a system to control air flow into the heap. The air flow control system comprises a combination of an air impermeable barrier and an aeration system.

Abstract: A liquid injection process for in-situ leaching and extracting an ion-adsorption type rare earth including: setting up a liquid injection network having liquid injection shallow wells and liquid injection deep wells, inputting a leaching agent into the injection shallow wells, then inputting the leaching agent into the deep wells, and finally inputting a pushing water into all of the wells. This process is characterized by a high rare earth mineral-leaching rate, a high mother liquid concentration, a small residue of the mother liquid of the ore earth, a small unit consumption of the leaching agent, simple operation, wide application, and outstanding environmental protection effect. Additionally, the process also can cancel any blind area in mineral leaching, increase stability of side slope in the liquid injection process, and control a flow direction, a flow rate of the leaching agent, and a liquid injection intensity.

Abstract: A method of leaching a metal value from a heap of a metal-containing ore and a heap leaching operation are disclosed. The method includes establishing a downward flow of a leach liquor through a section of the heap by supplying the leach liquor onto a top surface of the section and allowing the leach liquor (containing metal values in solution) to drain from a lower part of the section. The method is characterized by supplying the leach liquor onto the top surface of the section at a flow rate that is sufficient so that the downwardly flowing leach liquor saturates the section of the heap.

Abstract: Porous leach pipe and method for leaching metals from mining ores. The porous pipe may be buried beneath the surface of a pile of mined ore, providing a more even and uniform distribution of the leaching solution across the pile, increasing metal yields, reducing water consumption and eliminating pooling and ponding of the solution on the top of the piles as occurs with prior art drip line emitters.

Abstract: A process for producing metal compounds directly from underground mineral deposits including steps of forming a borehole at a site into a mineral deposit containing metal compounds, inserting a slurry-forming device having a nozzle into the borehole adapted to direct pressurized water through the nozzle into the mineral deposit, supplying pressured water through the nozzle into the mineral deposit forming a mineral slurry containing metal compounds, extracting the mineral slurry containing metal compounds through the borehole, leaching the mineral slurry converting the metal compounds to a soluble form in a leach solution, and removing metals and metal compounds by treating the leach solution with an extraction treatment removing the metal products. Steps of leaching the mineral slurry and removing metal products are performed at a location remote from the borehole site. In one alternative, the step of removing metal products from mineral slurry is accomplished by pyrometallurgical processes.

Abstract: A process for leaching an ore containing sulfidic copper-containing minerals includes carrying out an aerated oxidizing leach of a part of the ore and producing an acidic leach liquor containing ferrous ions, ferric ions, and copper ions in solution. The process also includes carrying out a leach of another part of the ore using the leach liquor under conditions that minimize reactions with a source of iron in the ore and producing a leach liquor containing copper ions in solution. The process further includes recovering copper from the leach liquor.

Abstract: The invention relates to a method of recovering molybdenum from a molybdenum bearing sulfide material. The material is contacted with a leaching solution in the presence of iron compounds and mesophilic or thermophilic iron oxidizing microorganisms and subsequently, a leaching process is performed by controlling the molar ratio of dissolved ferric iron to dissolved molybdenum. Preferably, a high amount and molar excess of dissolved iron is used. The presence of high concentrations of ferric iron in bioleach solutions allows iron-oxidizing microorganisms to grow and oxidize iron and bioleach molybdenite at dissolved Mo concentrations as high as 4.4 g/L. Organic metabolites were not required for protecting cells from Mo toxicity. Maximum dissolution rates depend on reactor configuration, with agglomerated material simulating heap leaching of almost 1% Mo/day, but up to 10.2% Mo/day in suspension/stirred reactor configurations, with rate highly dependent on temperature within the range of 25° C. to 40° C.

Abstract: Nickel entrained in the sulphide mineral pyrrhotite is engineered to dissolve in leaching acid in a two step procedure. First, a slurry of the mineral and the acid is activated by oxidation. This is done in a time T1 by electrolysis; or alternatively chemically, by adding e.g an oxidizing acid to the mineral. After activation, the slurry is then kept under anoxic conditions for a time T2. During T2, the sulphide starts to dissolve much more rapidly, and the rapid breakdown of the sulphide enables the nickel to dissolve and thus to be leached out of the mineral. The dissolved nickel is extracted from the leaching acid e.g by electro-winning.

Abstract: A process for the heap leaching of multiple ores, the process characterized by the process steps of: (i) the agglomeration or wetting of an ore feed; (ii) exposing the agglomerated or wetted ore to an inoculum containing one or more bacterial species capable of biooxidizing sulphide minerals in that ore; (iii) forming one or more heaps from the ore of step (ii); (iv) dispersing further bacterial inoculum over at least a portion of the or each heap; and (v) recovering leach solution draining from the heap and passing a portion thereof to a means for metal recovery.

Abstract: A method of biotreating and recovering metal values from metal-bearing refractrory sulfide ore using a nonstirred surface bioreactor is provided. According to the method, the surface of a plurality of coarse substrates is coated with a solid material to be biotreated to form a plurality of coated coarse substrates. The coarse substrates have a particle size greater than about 0.3 cm and the solid material to be biotreated has a particle size less than about 250 ?m. A nonstirred surface reactor is then formed by stacking the plurality of coated coarse substrates into a heap or placing the plurality of coated coarse substrates into a tank so that the void volume of the reactor is greater than or equal to about 25%. The solid material is biotreated in the surface bioreactor until the undesired compound in the solid material is degraded to a desired concentration.

Abstract: A system and method are disclosed for improving component extraction from heap leach operations. Following heap leaching for some time, portions of the heap deficient in component extraction are identified, and treatment wells are drilled and remedial treatments are selectively performed on the identified portions of the heap. The remedial treatment can include hydraulically fracturing the identified portions of the heap followed by selective treatment with leach solution of the area impacted by the fracturing.

Abstract: A heap is constructed with hypogenic copper sulfide bearing ore to include exposed sulfide mineral particles at least 25 weight % of which are hypogenic copper sulfides. The concentration of the exposed sulfide mineral particles is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. At least 50% of the total copper in the heap is in the form of hypogenic copper sulfides. A substantial portion of the heap is heated to at least 50° C. The heap is inoculated with a thermophilic microorganism, and bioleaching is carried out so that sufficient sulfide mineral particles in the heap are biooxidized to oxidize at least 10 Kg of sulfide sulfur per tonne of solids in the heap and to cause the dissolution of at least 50% of the copper in the heap in a relatively short period of time.

Abstract: A method of alleviating dust in the early stages of metal ore processing, such as copper ore, through mining the ore through concentration involves spraying and wetting crushed ore rock and ground particles and dust at least several of a series of locations with a dust suppressant containing major amounts of water plus minor amounts of an additive combination of glycerol and a selected non-ionic surfactant, and passing the wetted particles and dust to a metal concentrator where the additive combination does not interfere with metal concentration yield.

Abstract: A process for improving recovery of metal values in a smelting operation of the type wherein sulfidic ores are pyrometallurgically reduced. The process includes adding an anionic or non-ionic surfactant and blends thereof to the ore.

Abstract: The invention publishes a process to increase the bioleaching speed of ores or concentrates of sulfide metal species in heaps, tailing dams, dumps, or other on-site operations. The process is characterized by the continuous inoculation of the ores or concentrates with isolated microorganisms of the Acidithiobacillus thiooxidans type, together with isolated microorganisms of the Acidithiobacillus ferrooxidans type, with or without native microorganisms, in such a way that the total concentration of microorganisms in the continuous inoculation flow is of around 1×107 cells/ml to 5,6×107 cells/ml. In particular, the invention publishes the continuous inoculation of Acidithiobacillus thiooxidans Licanantay DSM 17318 together with Acidithiobacillus ferrooxidans Wenelen DSM 16786 microorganisms, or with other native microorganisms at a concentration higher than 5×107 cells/ml.

Abstract: The invention relates to a method of recovering molybdenum from a molybdenum bearing sulfide material. The material is contacted with a leaching solution in the presence of iron compounds and mesophilic or thermophilic iron oxidizing microorganisms and subsequently, a leaching process is performed by controlling the molar ratio of dissolved ferric iron to dissolved molybdenum. Preferably, a high amount and molar excess of dissolved iron is used. The presence of high concentrations of ferric iron in bioleach solutions allows iron-oxidizing microorganisms to grow and oxidize iron and bioleach molybdenite at dissolved Mo concentrations as high as 4.4 g/L. Organic metabolites were not required for protecting cells from Mo toxicity. Maximum dissolution rates depend on reactor configuration, with agglomerated material simulating heap leaching of almost 1% Mo/day, but up to 10.2% Mo/day in suspension/stirred reactor configurations, with rate highly dependent on temperature within the range of 25° C. to 40° C.

Abstract: A heap is constructed with hypogenic copper sulfide bearing ore to include exposed sulfide mineral particles at least 25 weight % of which are hypogenic copper sulfides. The concentration of the exposed sulfide mineral particles is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. At least 50% of the total copper in the heap is in the form of hypogenic copper sulfides. A substantial portion of the heap is heated to at least 50° C. The heap is inoculated with a thermophilic microorganism, and bioleaching is carried out so that sufficient sulfide mineral particles in the heap are biooxidized to oxidize at least 10 Kg of sulfide sulfur per tonne of solids in the heap and to cause the dissolution of at least 50% of the copper in the heap in a relatively short period of time.

Abstract: The invention relates to recovering metals, such as nickel and cobalt, by phytomining or phytoextracting soils rich in metals wherein the desired metal is selectively accumulated in hyperaccumulator plants by adjusting the soil pH. The metals are ultimately recovered from above-ground plant tissues at economically acceptable levels without further contaminating the metal-containing sites. The invention also relates to metal-hyperaccumulating plants.

Abstract: The invention includes methods for (1) extracting metals from soil by the use of plants that extract and accumulate the metal and adding bacteria to the soil that enhances the ability of the plants to extract the metal, and (2) preparing soil for extraction of a metal by plants by adding bacteria to the soil that enhances the ability of plants to extract the metal. It is preferred that the plants be planted in the soil as seeds and that the bacteria added to the soil is also added to the seeds prior to planting.

Abstract: Processes and materials for phytoremediating water-containing sites which have been contaminated with pollutants such as arsenic, phosphorous, or other metals. Fern plants can be used to accumulate pollutants from contaminated water-containing sites having an aqueous solution, waste water, ground water, surface water, combinations thereof, and combinations of water-containing sites with soils and/or sediments. The fern plants remove pollutants from the water-containing sites, and can be harvested and readily disposed of, or can be treated to recover the pollutant.

Abstract: Processes, methods, materials and compositions for phytoremediating contaminated waters, which have been contaminated with pollutants such as arsenic, phosphorous, or other metals. Fern plants can be used to accumulate pollutants from contaminated water, including aqueous solution, waste water, ground water, surface water, combinations thereof. Pollutants and contaminants can be removed from the water, soil and wetland type environment via foliar application, excised leaflets, and/or through compositions of ground leaflets. The biomass can be harvested and readily disposed of, or can be treated to recover the pollutants and contaminants.

Abstract: Processes, methods, materials and compositions for phytoremediating contaminated waters, which have been contaminated with pollutants such as arsenic. Fern plants that include Pteris and non-Pteris fern plants can be used to accumulate pollutants from contaminated water, including aqueous solution, waste water, ground water, surface water, combinations thereof. Pollutants and contaminants can be removed from the water, soil and wetland type environment via phytoremediation through roots and fronds as well as by applying excised portions of plants such as leaflets (cut-off fronds). The biomass can be harvested and readily disposed of, or can be treated to recover the pollutants and contaminants.

Abstract: A cadmium and zinc hyperaccumulating subspecies from Thlaspi caerulescense and methods for removing or recovering cadmium and zinc from soils by cultivating the Thlaspi caerulescense subspecies on soils containing cadmium and zinc.

Abstract: A method of producing edible Brassica plants capable of accumulating significant concentrations of selenium in edible portions of the plant. Edible Brassica plants were grown in an environment containing selenium, the plants were cultivated under conditions that allow enhanced uptake of the metal into edible portions of the plants, wherein the concentration of selenium accumulated in the edible portions of the plant is higher than the concentration of selenium in the environment. The plants are then harvested for further use.

Abstract: A procedure to agglutinate ore concentrations, which can be of copper, on a gravel heap, to be leached on a non-flooded bed which comprises: artificially adhering the concentrate to the surface of a solid material base, which can be an artificial material, or a stony substance; the agglutinated material is stockpiled, forming a leaching pile; and is irrigated with a leaching solution containing at least Cl, Cu, and Fe ions.

Abstract: A copper concentrate obtained by flotation of a high grade copper ore containing chalcopyrite as a main mineral constituent is leached at a temperature of 100° C. or higher, and under a pressure greater than atmospheric pressure yielding a copper leachate containing ferric ions of at least 5 g/L and sulfuric acid, and this copper leachate is used in heap leaching or vat leaching of a low grade copper ore, whereby a method of recovering copper economically from a material containing copper is provided.

Abstract: A method of leaching sulphide mineral concentrates wherein heat generated by bioleaching of sulphide mineral concentrates in at least one reactor is transferred into a heap in which bio-assisted leaching takes place.

Abstract: A method for continuously producing foamed metals is disclosed. The method comprises the steps of (i) adding a previously dissolved molten metal to a viscosity-enhancing furnace and agitating the molten metal so as to uniformly maintain the viscosity of the molten metal; (ii) conveying the molten metal to an electronic agitating type foaming furnace; (iii) injecting gas into the conveyed molten metal while agitating to obtain a foamed molten metal; and (iv) drawing the obtained foamed molten metal using a roller and cooling the drawn foamed metal.

Abstract: A method of recovering copper from a copper bearing sulphide mineral which includes the steps of subjecting the slurry to a bioleaching process, supplying a feed gas which contains in excess of 21% oxygen by volume, to the slurry, and recovering copper from a bioleach residue of the bioleaching process.

Abstract: Methods for detecting gold and quantitating gold in ore samples utilizing a gold-specific protein are provided, including methods for multiple sample handling. Also provided are methods for extracting gold from mineral suspensions utilizing a magnetic mineral binding reagent and gold-specific protein, or hydrophobic reagent and gold-specific protein in conjunction with a flotation reagent.

Abstract: According to the process, a heap preferably having dimensions of at least 2.5 m high and 5 m wide is constructed with hypogenic copper sulfide bearing ore. The constructed heap includes exposed sulfide mineral particles at least 25 weight % of which are hypogenic copper sulfides. The concentration of the exposed sulfide mineral particles in the heap is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. Furthermore, at least 50% of the total copper in the heap is in the form of hypogenic copper sulfides. A substantial portion of the heap is then heated to a temperature of at least 50° C. The heap is inoculated with a culture including at least one strain of thermophilic microorganisms capable of bioleaching sulfide minerals at a temperature above 50° C. A process leach solution that includes sulfuric acid and ferric iron is applied to the heap.

Abstract: The present invention relates to process control where some of the controllable parameters are difficult or impossible to characterize. The present invention relates to process control in biotechnology of such systems, but not limited to. Additionally, the present invention relates to process control in biotechnology minerals processing. In the inventive method, an application of the present invention manipulates a minerals bioprocess to find local exterma (maxima or minima) for selected output variables/process goals by using a learning-based controller for bioprocess oxidation of minerals during hydrometallurgical processing. The learning-based controller operates with or without human supervision and works to find processor optima without previously defined optima due to the non-characterized nature of the process being manipulated.

Abstract: The recovery of nickel, cobalt and other metals by phytomining is described. Plants of the Alyssum genus are grown in nickel rich soil. The uptake of nickel is enhanced by maintaining specific soil conditions, including a concentration of calcium between (but not including) 0.128 mM an 5.0 mM and an acidic pH. Ni uptake may be further enhanced by maintaining a ratio of exchangeable Ca/Mg of 0.16-0.40. Uptake may be further enhanced by addition of chelating agents and ammonium based fertilizers.

Abstract: A method and apparatus for solar heating a leach solution prior to its distribution over an ore heap. The apparatus includes a heat absorbing mat having a series of individual heat absorbing tubes joined to each other by heat reflecting panels. The heat reflecting panels and heat absorbing tubes collect and transfer solar energy to the leach solution passing through the heat absorbing tubes. The temperature of the leach solution passing through the heat absorbing tubes is elevated above ambient prior to the leach solution being distributed to a series of emitter tubes positioned on top of the ore heap. The array of emitter tubes are connected to the heat absorbing mats such that the leach solution is heated within the mat and immediately distributed to the emitter tubes for distribution onto the ore heap.

Abstract: A method of extracting zinc from a sulphidic ore is provided which comprises bioleaching the ore in a heap with acidophilic microorganisms to produce a pregnant leach solution which is recovered from the bottom of the heap. An integrated process which comprises subjecting the pregnant leach solution to neutralization and solvent extraction to produce a concentrated zinc solution is also provided. Zinc may be recovered from the concentrated solution by means of electrowinning, either in the absence or presence of manganese. Alternatively zinc may be recovered in the form of a zinc compound.

Abstract: A method of recovering nickel from a nickel bearing sulphide mineral slurry which includes the steps of subjecting the slurry to a bioleaching process, supplying a feed gas which contains in excess of 21% oxygen by volume, to the slurry, and recovering nickel from a bioleach residue of the bioleaching process.

Abstract: Material is decontaminated of a pollutant by using perennial woody plants with the ability to accumulate the pollutant in the leaves in high concentrations. The decontamination is based on a combination of phytoextraction, pollutant transport with the falling of the leaves to the material surface, leaching of the pollutant out of the leaves decomposing on the material surface, and (physico-)chemical fixing of the pollutant in a reactive layer which is bounded by geotextiles and which physically and/or chemically binds the pollutant.

Abstract: A method of recovering precious metal values from refractory sulfide ores is provided. The method includes the steps of separating clays and fines from a crushed refractory sulfide ore, forming a heap from the refractory sulfide ore, producing a concentrate of refractory sulfide minerals from the separated fines and adding the concentrate to the heap, bioleaching the heap to thereby oxidize iron sulfides contained therein, and hydrometallurgically treating the bioleached ore to recover precious metal values contained therein.

Abstract: Improved methods are disclosed for the efficient and cost-effective recovery of zinc metal from zinc-containing brines. Zinc is first bound to an anionic ion exchange resin (IX) which has been equilibrated with a solution containing a reducing agent, washed, and eluted with an elution solution. A reducing agent can be added to the brine prior to loading on the IX and can optionally be added to the IX after the washing step. The eluted zinc is extracted with a water-immiscible cationic organic solvent (SX), which is scrubbed, then stripped with concentrated acid. Substantially pure zinc is recovered by electrowinning the zinc-loaded concentrated acid solution.

Abstract: Methods and compositions for increasing the recovery of precious metals from ore during heap leaching operations are disclosed. The methods add polypropylene glycol and alkylphenol ethoxylate in a paraffin oil solvent with the cyanide lixivant to the ore heap.

Abstract: A method of biotreating a solid material to remove an undesired compound using a nonstirred surface bioreactor is provided. According to the method the surface of a plurality of coarse substrates is coated with a solid material to be biotreated to form a plurality of coated coarse substrates. The coarse substrates have a particle size greater than about 0.3 cm and the solid material to be biotreated has a particle size less than about 250 &mgr;m. A nonstirred surface reactor is then formed by stacking the plurality of coated coarse substrates into a heap or placing the plurality of coated coarse substrates into a tank so that the void volume of the reactor is greater than or equal to about 25%. The reactor is inoculated with a microorganism capable of degrading the undesired compound in the solid material, and the solid material is then biotreated in the surface bioreactor until the undesired compound in the solid material is degraded to a desired concentration.

Abstract: A process for leaching an ore that contains nickel and magnesium includes mixing a microorganism that is capable of producing an organic acid, a nutrient, and an ore that contains nickel and magnesium for a period of time to dissolve the nickel and form a solution containing a nickel salt and a magnesium salt, separating the nickel from the magnesium in the salt solution.

Abstract: A method of recovering precious metal values from refractory sulfide ores is provided. The method includes the steps of separating clays and fines from a crushed refractory sulfide ore, forming a heap from the refractory sulfide ore, producing a concentrate of refractory sulfide minerals from the separated fines and adding the concentrate to the heap, bioleaching the heap to thereby oxidize iron sulfides contained therein, and hydrometallurgically treating the bioleached ore to recover precious metal values contained therein.

Abstract: The invention provides processes and materials for phytoremediating materials which has been contaminated with arsenic, phosphorous, or other metals. In a preferred embodiment, the subject invention provides fern plants, which accumulate arsenic from contaminated materials. The fern plants efficiently remove arsenic from the materials. The fern plants can be harvested and readily disposed of, or can be treated to recover arsenic.

Abstract: The emissions of hydrogen sulfide during the production of natural gas, oil or geothermal fluids from subterranean formations and the subsequent processing of these fluids is reduced by converting the hydrogen sulfide into a hydrogen halide or a halogen acid and then using the hydrogen halide or halogen acid for scale control and/or well acidizing. In a preferred embodiment, hydrogen sulfide produced with geothermal fluids is converted into hydrochloric acid, which is then used to reduce pH and control scale formation during the extraction of energy from geothermal fluids in a geothermal power plant.