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Copper & Nickel Solvent Extraction
Table of ContentsExperimental Techniques and EquipmentExperimental ResultsExtractionEffect of pHEffect of Ammonium Sulfate ConcentrationSulfate and Carbonate Liquor ComparisonsPreferential LoadingLiquor ImpuritiesExtraction IsothermsKinetics of ExtractionExtraction Versus AgitationExtraction Versus Time and TemperatureEffect of Ammonium Sulfate ConcentrationEffect of Residence Time in Extraction MixerStrippingNickel-Copper SeparationStripping IsothermEffect of Residual Acid on Nickel StrippingKinetics of StrippingStripping Versus Time and TemperatureEffect of Residence Time in Stripping MixerContinuous Circuit25-vol-pct-LIX 64N
Sodium Silicate Uses & Applications
The practical application of common alkaline inorganic chemicals such as lime, soda ash, caustic, silicates and phosphates, in the beneficiation of minerals, is well known within the industry. These materials have been found to be useful throughout the flotation circuit. This paper discusses the chemistry of the soluble sodium silicates in relation to their use in flotation regulation as depressants,
Sludge Dewatering by Pressure Filtration
Pilot test results with 30% refuse slurry suggested the installation of two (2) Passavant Pressure Filters, Model 20 with 150 chambers each and a cake thickness of 40 mm. Each filter plate is 2m x 2m in size and the total cake capacity of each filter is 762 cu. feet. The sludge pumping requirements, per cycle, are approximately 71.92 cu.m.
Effect of Chemical Dispersants on Hydrocyclone Efficiency
A series of tests on a 24 inch hydrocyclone operating on a copper ore slurry were run. The ore was selected so as to be reasonably homogeneous with regard to the density of components so that particle size differences dominate the classifier action. The primary variables were % solids (and associated viscosity readings), the feed rate of slurry, and the
Uranium Leaching Lixiviants
Table of ContentsUranium Leaching AgentsAlkaline (Carbonate Bicarbonate) LixiviantsAmmonium Carbonate-BicarbonateSodium Carbonate-BicarbonatePotassium Carbonate-BicarbonateCarbon DioxideAcid LixiviantsSulfuric AcidNitric and Hydrochloric AcidsOxidizersOxygenHydrogen PeroxideChloratesMethods of Testing LixiviantsLaboratory TestsBatch LeachingColumn LeachingPilot Field TestsTypes of TestsProblems and SolutionsGeochemical ModelsSummary This Bureau of Mines publication provides information to assist in selecting a lixiviant (leach solution) for in situ uranium leaching. The cost, advantages, and disadvantages of lixiviants currently used
How to Remove Sulphur from Coal
Reducing the inorganic sulfur in coal to tolerable limits by physical beneficiation, including flotation, as now practiced, still is relatively inefficient and has not kept pace with the more sophisticated physical beneficiation approaches employed by the nonfuel minerals industry in general. As one phase of a broad program conducted by the Mineral Resources Institute on the sampling and evaluation of
Remove Iron by Solvent Extraction in Aluminum Chloride Leach Solution
Table of ContentsEquipment and ProceduresSolvent Extraction Mixer-SettlersCoalescerCarbon ColumnCarbon Mixing-FiltrationExtraction and Stripping SamplesCoalescer Discharge SamplesCarbon Column SamplesCarbon Mixing-Filtration SamplesExperimental ResultsIron ExtractionIron StrippingMaterial BalanceIron BuildupMinor ImpuritiesRemoval of Entrapped OrganicsConclusions As part of its mission to maintain an adequate supply of minerals to meet national needs and maximize mineral production from domestic sources, the Bureau of Mines is investigating the recovery of alumina
How to Recycle Magnesite Chrome in Copper Smelting Furnaces
Table of ContentsDescription of SamplesChemical AnalysesMineralogical AnalysesParticle-Size DistributionBeneficiationMagnetic SeparationFlotationContinuous FlotationLeachingRefractory StudiesPreparation of SamplesChrome Concentrates From Copper Smelter LiningsEnvironmental ConsiderationsRecycling Waste Refractories in Copper Smelting Furnaces In accordance with its objective to maximize minerals recovery from secondary domestic resources, Bureau of Mines conducted research on recycling chrome refractory wastes. Since 20 pct of the U.S. demand for imported chromite is used
Chlorine Oxygen Leaching Process
Table of ContentsMaterials and EquipmentFeed PreparationLeachingSolvent ExtractionMetal RecoveryProceduresLeachingSolvent ExtractionMetal RecoveryResults and DiscussionLeachingLiquid-Solid SeparationSolvent ExtractionMetal RecoveryRecovery of Metal in Lead Smelter Matte by Chlorine Oxygen Leaching To increase metal recoveries and to minimize pollution by improved extraction technology, the Bureau of Mines investigated a hydrometallurgical technique to recover copper, lead, nickel, and cobalt from lead smelter mattes. The metals were converted
Recovery of Lithium by Chlorination
Table of ContentsThermodynamicsMaterials, Equipment, and Test ProceduresMaterialsEquipmentProcedureTest ResultsChlorination With Anhydrous HClSelective Chlorination With HCl-H20 MixturesSelective Chlorination of Clay-CaCO3 Mixtures With HCl-H2OConclusions The Bureau of Mines studied the extraction of lithium from lithium- containing clays by chlorination with hydrogen chloride (HCl). In bench-scale laboratory investigations, HCl-H2O mixtures were used to selectively chlorinate lithium, but not calcium or magnesium, in lithium-containing clays.
How to Recover Copper & Precious Metals in Electronic Scrap
Table of ContentsExperimental ProceduresMultiple-Pin Plugs and ConnectorsObsolete Aircraft Radio AssembliesMagnetic Electronic ScrapConclusions As a part of a research program designed to help minimize national requirements for new mineral commodities by maximizing recovery of metals from domestic secondary resources, the Bureau of Mines investigated the development of economic methods for recovering copper and associated metals from complex electronic scrap. Three types
Heavy Minerals Recovery from Sand & Gravel
Table of ContentsHeavy Mineral Sampling and CharacterizationBeneficiationGravity ConcentrationSeparation of Heavy Mineral ConcentratesMoclips Beach SampleSouth Santiam and Umpqua SamplesSouthfork Coquille SampleDiscussion and Conclusions We investigated methods for the recovery of byproduct heavy minerals from sand and gravel operations in Oregon and Washington. These heavy minerals are not currently recovered except for gold in a few areas. The recovery of byproduct heavy
Recover Scrap Chromium by Pyrometallurgy Process
Table of ContentsRaw MaterialsGeneral ApproachesSelected ApproachExperimental ProgramMetal SamplesOther Charge MaterialsApparatus50-kW Furnace20-kW FurnaceMethodOxidation ExperimentsReduction ExperimentsResults and DiscussionsScrap MeltingChromium OxidationChromium RecoveryDistribution of Principal ElementsSeparation Between Chromium and IronSeparation Between Chromium and Cobalt and NickelSeparation Between Chromium and Other Alloying ElementsOxygen UtilizationSlag-Metal SeparationReduction of Chromium-Bearing SlagsReduction with FerrosiliconReduction With Other Reducing AgentsFuture ResearchConclusionsAppendix.—Analytical MethodsStandard Analytical MethodsSelection of Analytical MethodDevelopment of Sample Preparation ProcedureAnalysis
Ni-Cd Nickel Cadmium Recovery Method in Scrap Batteries
Table of ContentsBattery Construction and CompositionBench-Scale TestsExplosion of Cadmium CondensatesLarger Scale TestsRetort MaterialCadmium Condenser DesignBattery Material PreparationTen-Pound Retort TestsTwenty-Five-Pound Retort TestsForty-Three-Pound Retort TestsCadmium EmissionsFuel Gas ConsumptionFurther Research NeedsFusionFurnace DesignCadmium CondenserConclusions As part of a continuing effort to maximize metal recovery from domestic secondary resources, the Bureau of Mines investigated a process for recovering the metallic portion of scrap alkaline batteries.
Making Acid Iron Ore Pellet
Table of ContentsPlant Test PreparationMixing experiments with tracer materialConclusion In 1976 CVRD started the investigation of organic binders application for iron ore agglomeration. The ore was mixed in a Eirich Mixer with quantities of Peridur ranging from 0.1 to 0.4% and pellets were prepared in a laboratory disk. At first the results were not satisfactory at all. The wet and
How to Recover Chrome Metal from Scrap Alloy
Table of ContentsFluidized-Bed Roasting of Chromium SulfideChemical ReactionsExperimental ProcedureReactor DesignRaw MaterialsResultsEffect of Water ContentEffect of Initial Particle SizeMinimum Final Sulfur ContentAluminothermic Reduction to Chromium MetalChemical ReactionsExperimental ProcedureRaw MaterialsTesting ProcedureResultsDesulfurizationMaterial BalanceLeaching Nickel ScrapRaw MaterialsBatch Chlorine Leaching TestsEffect of Copper ActivationEffect of Redox Potential ControlCopper RemovalCCD Countercurrent Leaching SystemRaffinate PurificationContinuous Leaching TestsResults of First Continuous TestResults of Second Continuous TestCleaner Leach of
Process for Recovering Chromium Scrap
Table of ContentsCurrent Chromium Recycling MethodsTreatment of Superalloy Scrap to Recover Individual ElementsTechnical Approach for this ProcessExperimental WorkSuperalloy ScrapComposition of Superalloy ScrapForm of Superalloy ScrapRaw Materials UsedMelting and CastingOxidation TestsTesting ProcedurePreferred DeoxidantQuantity of Oxygen RequiredRate of DeoxidationCharacter and Composition of SlagRecovery of MetalsSulfidation TestsTesting ProcedureMicrostructure of Superalloy MatteEffect of Sulfur Content on Element DistributionEffect of Base CompositionEffect of Cooling Rate on
AG Autogenous Grinding Power Efficient
Table of ContentsAutogenous Grinding EfficiencyIntermediate Autogenous Grinding The importance of efficient use of power in autogenous grinding circuits has been greatly neglected. It should be the fundamental factor in considering the design of an autogenous plant to grind a particular ore. The steps in the process used to arrive at a power efficient commercial autogenous plant for a particular ore are
Mobile Rock Crusher
Table of ContentsHow It WorksTest ResultsPatent Status This Mobile Rock Crusher provides a portable crushing capability to keep conveyor haulage close to the working face and permit more efficient and safer ore handling in low headroom, hardrock mines. A readily portable jaw crusher is used which meets machine size, feed rock size, product size, and throughput requirements for low headroom, hardrock
Molybdenite Flotation
Table of ContentsMolybdenite Extraction PlantMolybdenite Plant Feed ThickenerCyanide Leach CircuitFuel Oil for Molybdenite FlotationDifferential Flotation Process for Recovery of Molybdenite from Copper ConcentratesSelective Flotation of MolybdeniteEh in Molybdenite Flotation Factors Directly Affecting Molybdenite Flotation: The average molybdenite recovery in the copper concentrator for the first nine months of 1980 was 67.13%. In recent months, there has been approximately an 80% recovery of the
Cold Vapor Determination of Mercury by AA
Table of ContentsExperimentalEquipmentReagents and StandardsFabrication and Modification of EquipmentAssembly of the SystemSample PreparationInstrument AdjustmentAnalysis ProcedureResultsDiscussion and Conclusions The Bureau of Mines once modified a commercial atomic absorption spectrophotometer to rapidly determine trace levels of mercury by cold-vapor atomic absorption spectrophotometry AA. Such diverse materials as ores, mill products, stream water, sediments, and flue dust have been analyzed. A very high
How to Reduce Steel Consumption in Grinding Mills
Table of ContentsFactors Involved in Steel WearMethods of Steel Wear ReductionImproved Composition of Steel LinersImprove Composition of Steel MediaImproved Design of LinersImprove Mill Operating ConditionsReagent to Help Reduce Steel ConsumptionComposite Materials for Ball Mill LinersRubber Liners The fact that over 25% of the original weight of steel liners and balls is discarded as waste is probably one of the factors
Dump Leaching Copper Recovery
Table of ContentsMaterials and MethodsMineralogy of the SamplesSample Preparation and CharacterizationTest Procedures and EquipmentLeaching MechanismsCopper Recovery by CementationCopper Recovery by Solvent Extraction-ElectrowinningExperimental ResultsLeaching the Coarse OreCopper ExtractionAcid ConsumptionIron Content of the Leach SolutionsOre PermeabilityBacterial ActivityLeaching the Fine OreCopper ExtractionAcid ConsumptionIron Content of the Leach SolutionsOre PermeabilityBacterial Activity Leaching of porphyry copper mine strip wastes and low-tenor ores provides a substantial
Mixer Settler System
Table of ContentsThe SettlerMixer-Settler Development The KREBS Mixer-Settler as shown on Fig. 1 includes the following features: A MIXING IMPELLER selected to best satisfy dispersion requirements. A low turbulence CONICAL PUMP, built around the impeller shaft, to transfer the dispersion from the mixer to the settler and induce phase separation. A SUPERPOSED LAUNDER provides further phase separation and makes it