Blogs

Electrowinning MischMetal

Table of ContentsMaterialsExperimental Procedures and ResultsSustained Performance of Electrolyte SystemDetermination of Optimum Electrolyte CompositionElectrowinning and Tapping of Misch Metal For many years, we conducted a research program on electrolytic preparation of rare-earth metals. Cerium, lanthanum, and neodymium, praseodymium, and didymium metals have been electrowon from their respective oxides dissolved in fluoride melts. Commercial production of mischmetal, a mixed rare-earth metal

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Roasting Copper Sulfides Chemistry

Table of ContentsMaterials and ReagentsConversion of Covellite to DigeniteReaction Sequence in Roasting The roasting process is widely used in extracting copper from its sulfide ores. At present the development of a new process for winning copper from pelletized chalcocite concentrate is underway at the Bureau of Mines Twin Cities Metallurgy Research Center. In this process, the dead roasting of sulfide

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Using Rock Bolts or Wire Rope to Increase Fractured Pillar Strength

Table of ContentsTheoryRock-Bolting ModelWire-Roping ModelExperimental ProceduresSample PreparationCalibration Procedures for Rock-Bolt StudyCalibration Procedures for Wire-Rope StudyData and AnalysisRock-Bolt StudyWire-Rope StudyFinite Element Analysis of the Wire Rope Experiments In a room-and-pillar system of mining in which no artificial support is used (linings, sets, props, etc.), the weight of the overlying cover is sustained in part on the abutment and in part by

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Building a Junk Car Incinerator

Table of ContentsDesign and OperationDesignOperationResults of Preliminary Test Runs Congress, by the Solid Waste Disposal Act of 1965, delegated to the Bureau of Mines responsibility for conducting research on solid waste problems. The accumulation of abandoned automobiles is one of these problems, and this paper reports the efforts of the Bureau’s Salt Lake City Metallurgy Research Center in attempting to

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Coal Free-Swelling Index Testing

Table of ContentsMethod of TestingResultsDiscussion of ResultsConclusionsAppendix.-Astm Standard Method of Test for Free-Swelling Index of CoalApparatusCalibrationPreparation of SampleProcedure The term “free-swelling” is applied to the behavior of some bituminous coals when heated under specified conditions. Damm defined the swelling of coal as the volume change that takes place when coal is heated. The softened coal can expand, for example due

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How to Control Sulfur Oxide Emissions in Smelting

Table of ContentsCopperLeadZincDimension of the ProblemAir Pollution RegulationsSmelting PracticeCopperLeadZincSmelter GasCurrent Practice for Sulfur Dioxide ControlStatus of Technology for Removing Sulfur Dioxide from Smelter GasesConversion of SO2 to SO3 for Acid ProductionSeparation and Concentration of SO2Reaction of SO2 to Yield Solid Sulfur CompoundsReduction of SO2 to Elemental SulfurApproaches to Solving the ProblemSulfur ProductsCost of Compliance The domestic base-metal-producing industry has been

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How to Recover Cadmium & Nickel from Scrap Batteries

Table of Contents Scrap Battery Composition and ConstructionHow to Recover Cadmium & Nickel from Scrap BatteriesRoastingProduct RecoveryLixiviator RegenerationCarbon Dioxide RemovalNickel RemovalCyclic Leaching of Roasted Battery PlatesBench-Scale Cyclic Leaching ApparatusPreliminary Leach TestsEffect of Acidic Versus Basic LeachingMulticycle Leach TestFinal Cadmium-Nickel Leach TestSmelting of ResidueConclusionAnalytical Determination of Naphthenic Acid The manufacture and use of nickel-cadmium alkaline storage batteries in the United States began

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Recycling and Disposal of Solid Mining Wastes

Table of ContentsExtraction of Mineral, Metal, and Energy Value from Urban RefuseMunicipal Incinerator ResiduesUnburned Municipal RefuseReclamation and Reuse of Waste GlassRefining of Metals from RefuseUtilization of Discarded PlasticsPyrolysis of Solid WastesConversion of Organic Refuse to OilUpgrading and Utilization of Automotive and Related Ferrous ScrapJunk Car IncineratorIncreased Use of Ferrous Scrap in Electric Furnace SteelmakingProduction of Foundry Pig Iron From Junk

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How to Recover Copper from Slag by Flotation

Table of ContentsDescription of Slag SamplesPreparation of Slag SamplesBatch Flotation TestsFlotation Test ProcedureFlotation of Copper From Slow-Cooled Converter SlagsFlotation of Copper from Water-Quenched Converter SlagsGrindability DeterminationsCost Estimate for the Flotation of Copper from Converter SlagsProcess for Slow-Cooled SlagProcess for Quenched SlagCost EvaluationHow to Recover Copper from Slag by Flotation The bulk of the world’s output of copper is produced by smelting

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How to Recover Nonferrous Metals from Auto Shredder Rejects

Table of ContentsQuantity Composition and Value of Auto Shredder Reject MaterialEquipment Selection and DesignHorizontal ElutriatorVertical ElutriatorOperational ResultsHorizontal ElutriatorVertical ColumnCombined Operations Two major methods are available for effective recycling of metallic values in discarded automobiles. The first of these is the incineration, din- mantling, and baling or baling-shearing method. The economics of this operation were reported in 1969. The second procedure

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Electrowinning Tungsten

Table of ContentsAcid Digestion ProcessHCl Digestion of Scheelite ConcentrateElectrolysis of Crude OxideTwo-Phase Separation SequenceExtraction of WO3 from Scheelite ConcentrateElectrolysis of Halide-Tungstate MeltComparison of Electrowinning Techniques We demonstrated techniques for the electrowinning of tungsten directly from scheelite concentrate. The major problem with direct electrowinning is the accumulation of lime (CaO) in the electrolyte. Scheelite mineral concentrates usually contain 60 to 70

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Recover Uranium from Water by Countercurrent Ion Exchange

Table of ContentsDescription of Multiple-Compartment Ion Exchange ColumnMode of OperationTests With Kerr-Mcgee Oil IndustriesTest ResultsResin LossesTests at United Nuclear Corp.Countercurrent Elution StudiesComparison of Operating Results with Existing PlantsHydraulic Testing of a Six-Foot-Diameter Compartmented Column Ion exchange techniques have been used to recover uranium from waters pumped from uranium mines in the Ambrosia Lake district of New Mexico since about 1963.

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How to Sample Gold Lode Deposits

Table of ContentsClimateLiving ConditionsProperty and OwnershipHistory and ProductionGeneral GeologyMetasedimentary RocksIgneous RocksSurface FeaturesWork by the Bureau of MinesNature and ExtentPlacer InvestigationsBeach PlacersDaniels Creek PlacersKoyana Creek and Swede Creek PlacersEldorado Creek PlacersRyan Creek PlacersDetrital Cover SamplingDetrital Cover Sampling ResultsDaniels CreekBluff SchistsOther AreasLode DepositsGold Lode WorkingsMercury Lode WorkingsLode Sampling ResultsSpectrographic AnalysesSoil SamplingMill TailingsSummaryPetrography Placer and lode gold deposits near Bluff, Seward Peninsula, Alaska

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Sphalerite Leaching Kinetic

Table of ContentsOperationLeaching kinetic of original concentrateLeaching kinetic of the activated concentrate During roast, virtually all the iron in the concentrate feed is converted into zinc ferrite which remains almost inert in the neutral-leach stage. In order to recover zinc incorporated in ZnO·Fe2O3, a follow-up treatment of the leach residue is required. Ferric chloride is one of the ideal agent

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Heavy Liquid Separation

Table of ContentsContinuous Process DevelopmentDescription of the OreDescription of Heavy LiquidDescription of Continuous OperationMethods and ProceduresResults of Continuous Heavy Liquid Process DevelopmentTest Series A (Steam Stripping With Dry Feed)Pre conditioning CircuitCyclone CircuitRecovery CircuitTest Series B (Steam Stripping With Prewetted Feed)Preconditioning CircuitCyclone CircuitRecovery CircuitTest Series C (Steam Consumption)Preconditioning CircuitCyclone CircuitRecovery CircuitTest Series D (Steam-Stripping Time)Preconditioning CircuitCyclone CircuitRecovery Circuit We are continuously

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What is the Effect of Ammonia in Cyanide Solution during Copper Leaching

Table of ContentsMaterialsSource and Characteristics of Ore SampleSolventExperimental ProceduresResults and DiscussionFineness of GrindAmmonia EffectPulp Aeration and Temperature Under the conditions evaluated in this investigation, the extraction of copper from an argillaceous ore was not affected by the addition of ammonia to a cyanide solvent but was entirely dependent on the cyanide concentration. A number of investigators have evaluated cyanide complexes

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How to make Bricks from Mill Tailings

Table of ContentsBrick Specifications and Manufacturing MethodsTailing MaterialsLaboratory Test ProceduresPreliminary TestingTest VariablesDesulfided TailingsPilot-Plant Brick ProductionEconomics of Brick Production and Marketing Most of the primary copper produced in the United States is derived from porphyry-type ore deposits located in Arizona, Montana, Nevada, New Mexico, and Utah (Intermountain States). In milling these low-grade ores to produce a smelting-grade concentrate, enormous tonnages of

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Produce Convert & Make Copper Powder from Copper Cement

Table of ContentsCement Copper SamplesChemical AnalysesSample OxidationScreen AnalysesProcessing Cement Copper to a PowderFlotationVariations in Operating ConditionsParticle Size of the FeedOxidation of the Feed MaterialReagent AdditionsConditioning TimeFroth DepthAerationPulp TemperaturePulp pHPulp DensityCleaner FlotationFlotation of Various Copper SamplesChemical Purification of Flotation ConcentrateDigestion StudiesVariations in Solution CompositionVariations in Time and TemperatureCopper DissolutionPurification of the Various Flotation ConcentratesReduction, Sintering, and GrindingCopper Powder EvaluationProcess VariationsSintering TemperatureSintering

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How to Leach Copper Scrap

Table of ContentsColumn Leach TestsEffect of Solution Flow and Bubble-Entrainment AerationEffect of Solution FlowEffect of Aeration by Bubble EntrainmentEffect of Substituting Nitrogen for AirEffect of Leach TemperatureRecovery of Copper From Leach Solutions The starters, generators, and alternators recovered in scrapping up to 7 million junk automobiles annually are a significant source of recyclable copper. At present, the copper is recovered

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High Pressure Water Jet to Cut Concrete

Table of ContentsHigh-Pressure Pump and WaterlineWater Monitor and Test StandConcrete Test BlocksTesting ProcedureComputer AnalysisDesign of ExperimentDetermination of Physical PropertiesTreatment of DataResults of AnalysisDepth of PenetrationVolume of Material RemovedWidth of SlotEnergy EfficiencyConclusions Where water is abundant, hydraulic mining of placer deposits is usually the least expensive extraction system. In the past, large volumes of water were required, and pressures rarely exceeded

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Extract Silicate Rocks’ Oxygen by Electrowinning

Table of ContentsEvaluation of Electrode MaterialsElectrowinning Experiments In recent years, Bureau of Mines projects under the sponsorship of the National Aeronautics and Space Administration (NASA) have explored various aspects of the problems associated with establishing habitable stations on the Moon. The rapid advances in space technology, and particularly the success of the Apollo missions, indicate it is within reason to

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Chloride to Volatilize Gold

The Bureau of Mines has conducted extensive research to improve the extractive technology of gold and develop processes which may be applicable to refractory ores. Some metallurgists believe that the recovery of metallic values from ores and concentrates by vapor-transport techniques has great potential in the field of extractive metallurgy. The purpose of this phase of the Bureau’s research was

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Recover Vanadium by Electrolysis

Table of ContentsTheoretical ConsiderationsEquipment and ProcedureExperimental WorkDiscussion of ResultsInfluence of Cathode Current DensityQuality of the Vanadium ProductVanadium RecoveryElectrorefining of the Vanadium Products The preparation of ductile vanadium from vanadium carbide was investigated by the Bureau of Mines as a part of a research program on the extraction and utilization of vanadium resources. The vanadium was extracted from the vanadium carbide

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Improve Diamond Drill Penetration Rate

Table of ContentsStatistical Design of ExperimentEquipment and InstrumentationAnalysis of Experimental DataPenetration RateEnergyFrictionWearDiscussion of ResultsPenetration RateEnergy ConsumptionCoefficient of FrictionWear CoefficientDulling LifeDiamond Impregnated Bit Total LifeDiamond Surface Set Bit Total LifeStatistical AnalysisCost Analysis For some time researchers have attempted to increase drilling efficiency by adding certain agents to the flushing medium. Much of this interest is the result of the observations of

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