Blogs

Silver Barite Treatment Method

Table of ContentsCyanidation-Barite FlotationCyanidation TestsBarite Flotation of Cyanidation ResiduesSalt Roasting-Cvanidation-Barite FlotationSalt Roasting-Cyanidation TestsBarite Flotation of Salt Roasted-Cyanidation ResiduesBarite Flotation-Cyanidation and Flotation-Salt Roasting-CyanidationBarite FlotationCyanidation and Salt Roast-Cyanidation Tests on Composited Flotation Tailings The Calico mining district in California contains extensive deposits of low-grade silver ore. The deposits cover a large area and constitute an important silver reserve if difficult concentration problems

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Hydraulic Backfill Support

Table of ContentsFinite-Element Stope ModelRock PropertiesHydraulic Fill PropertiesComputer AnalysisComments on Computer AnalysesComparing Computer Results and Field MeasurementsFuture Research Mining companies have been confronted with a multitude of production problems in their endeavors to extract maximum quantities of ore at minimal costs. These problems are further compounded by the harsh mining conditions of deep vein operations, such as those found in

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Underground Mine Design

Table of ContentsGeneral Underground Mining ProblemLiterature ReviewDefinitions and Sample ProblemProblem FormulationSolution AlgorithmGeneral AlgorithmLeast-Cost Path AlgorithmDiscussion of Solution AlgorithmSample ProblemAlgorithm StructureImplementationApplication to a Coal PropertyComputational Experience The minerals industry in the field of Underground Mine Design is presently faced with the problem of meeting a rapidly increasing domestic and foreign demand for its mineral resources. This increased demand has added to

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Mine Water Chemistry – Is Process Water Hurting my Results

Mines are recycling more water than ever before. This is a logical response to water stresses (see our article on Water Balances).  However, there is a risk associated with the good stewardship of water.  Deleterious elements and compounds can concentrate in recycled mine water as it is recycled again and again, and these deleterious elements can decrease your recovery.  Levay

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Mill Tailings Dam Stability

Table of ContentsCopper IndustryIron IndustryLead and Zinc IndustryPhosphate IndustrySite DescriptionsCopper IndustryRay Mines Division, Kennecott Copper Corporation, Hayden, ArizonaMission Unit, ASARCO, Sahuarita, ArizonaPima Mine, Cyprus Pima Mining Co., Tucson, ArizonaWhite Pine Copper Company, White Pine, MichiganIron IndustryErie Mining Company Hoyt Lakes Plane, Hoyt Lakes, MinnesotaGroveland Mine, The Hanna Mining Company, Iron Mountain, MichiganPilot Knob Pellet Company, Ironton, MissouriLead and Zinc IndustryFletcher

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Rapid Particle Hydrosizing Size Analysis

Table of ContentsPrinciples of Analyzer SystemHydrosizingParticle SensingElectronicsProcedureExperimental ResultsSingle-Mineral ExperimentsTwo-mineral ExperimentsAnalyzer Prototype The knowledge of particle size distributions is a critical factor in the monitoring, control and optimization of many processes. This is particularly true of the mineral beneficiation industry, where comminution, the reduction of particle size, accounts for a major source of the processing costs. As an example, it is

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How to Analyse Blast Furnace Slag

Table of ContentsAnalytical MethodsTotal IronReagentsProcedureSilica and Mixed Oxides (SiO2 and R2O3)SilicaReagentsProcedureMixed OxidesReagentsProcedureCalculation of Crude AluminaManganeseReagentsProcedureAlternate Procedure for Slags Insoluble in Acid MixtureCalcium and MagnesiumReagentsProcedureTitaniumReagentsProcedureTotal SulfurReagentsProcedure From May 1951 to March 1967, the Bureau of Mines, as part of its iron and steelmaking research program, operated a series of experimental blast furnaces. The first furnaces were located in Pittsburgh; later furnaces

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How to Recover Zinc & Lead from Brass Smelter Dust

Table of ContentsReduction of Brass Smelter DustsEffect of Pelletization on the Vaporization of the ZincEffect of Sodium and Chloride Compounds on Vaporization of Lead and Zinc The recovery and recycling of metals from process wastes is a major research effort of the Bureau of Mines. The present work was undertaken by the Rolla Metallurgy Research Center to develop data that

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Rock Testing Procedure

Table of ContentsProperties of Materials and a Classification of Rock PropertiesA Philosophical Concept of MiningMining System DesignDesign for StabilityDesign for InstabilitySignificance of Rock PropertiesTheoretical Concept of Material PropertiesThermodynamic Equilibrium SystemSteady-State SystemSystem with HysteresisClassification of Rock Properties for Engineering PurposesInferred PropertiesPhysical PropertiesBasic PropertiesMechanical PropertiesNonmechanical PropertiesSection One-Inferred PropertiesAttenuation SymmetryCharacteristicsApplicationsSpecimen Preparation and ApparatusTest Conditions and LimitationsAnalytical ProcedureData Reduction and AnalysisElastic SymmetryCharacteristicsApplicationSpecimen PreparationApparatusTest Conditions

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Zinc Electrowinning & Impurities

Table of ContentsNo Impurity in the ElectrolyteImpurities in the ElectrolyteElectrolyses with Additives and/or Al and HClElectrolyses in the Presence of Pb CompoundsEffect of Ni on Zinc Deposits With Varying Process ConditionsElectrocrystallizationCathode Current Efficiency In the commercial electrowinning of zinc, zinc oxide is leached from the roasted calcine with an aqueous acid sulfate electrolyte. The zinc-rich solution is purified and then

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Hydrocyclone for Coal-Washing Equipment

Table of ContentsHydrocyclone Coal Washers and OperationHydrocyclone Coal WashersOperationSampling and Test ProcedureHydrocyclone FeedsPlant Operating ConditionsPerformance CriteriaDependent CriteriaIndependent CriteriaHydrocyclone Performance The profitable operation of a coal preparation plant under today’s stringent product standards and ever-rising labor, material, energy, and equipment costs requires that the preparation engineer continually strive for maximum recovery of salable coal. Good performance data are a prerequisite to

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Zirconium Oxide Molds for Molybdenum

Table of ContentsStatement of StatusStatement of the ProblemExperimental ProceduresFundamental ProcessSelection of Mold MaterialsSelection of BinderSlurry PreparationPreparation of Disposable PatternsMold ProductionPattern RemovalMold CuringFiringMelting and CastingFeed Material for MeltingCasting EvaluationEffects of Mold Preheat and of Static Versus Centrifugal CastingMold Metal ReactionMacrostructureMicrostructureMechanical PropertiesHardnessTensile PropertiesCorrosion Resistance One of the goals is to minimize the requirements for critical and strategic mineral commodities through conservation and

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Radial-Axial Loading Splitting Tool

Table of ContentsEquipment and MaterialsProceduresResults and DiscussionInfluence of Depth of BreakInfluence of Insertion AngleInfluence of Simultaneous BreaksInfluence of ForcesInfluence of ConfinementSimulated Drifting OperationApplication of ResultsEnergy EfficiencyExcavation RateCost AnalysisConclusions As a part of the Bureau of Mines research program to develop new mining methods for underground bedded deposits, a rock splitting tool capable of applying both radial and axial forces is

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How to Recover Chromium Nickel Cobalt Laterite

Table of ContentsLaterite ResourcesLaterite Geology and MineralogyExtent of ResourcesLeach Residue MineralogyCharacter of ResourcesChromite IdentificationBeneficiationChromite Recovery From Laterite Leach ResidueChromite Scavenging by Flotation or High-Intensity Wet Magnetic SeparationChromite Scavenging by Gravity SeparationChromite Recovery from LateriteUtilization of Chromite ProductsIron Coproduct RecoverySummary and Conclusions Chromium is essential to modern industry, and there are few acceptable substitutes for most of its metallurgical and chemical

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Gas Fired Iron Ore Pelletizing Kiln

Table of ContentsAcknowledgmentsPlant DescriptionPelletizing PlantGasification PlantCombustion Test ChamberGravitating Bed Gas ProducerLignite Gasification in Fixed-Bed ProducerSummary of 30-Day Gasification Test with Indianhead LignitePellet Induration with Raw Low-Btu Lignite GasConclusions The iron oxide pelletizing industry is very energy intensive and relies heavily on natural gas to fire pellet-indurating furnaces. Approximately 75 million long tons of iron oxide pellets are produced in the

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Effects of Velocity and Orientation on HydroCyclone

Table of ContentsLow-Velocity Studies (10-mm Cyclone)High-Velocity AreasHigh-Velocity StudiesEquipmentTest ProceduresAir VelocityInlet OrientationInlet ShieldingResultsDiscussion The 10-mm Dorr-Oliver cyclone is used for dust compliance sampling, which includes both stationary and personal sampling. The cyclone classifies “respirable” size particles, which are particles that reach the alveolar regions of the lungs, usually considered to have aerodynamic diameters (AED) of 10 µm or less. Although there

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How to Remove Mercury from Flotation Concentrate by Leaching & Electrolysis

Table of ContentsMaterials and ApparatusExperimental Procedures and ResultsLeachingElectrolysisContinuous Leaching-ElectrolysisEconomic EvaluationSummary and Conclusions Primary mercury metal is produced commercially by heating mercury sulfide concentrate in furnaces to vaporize mercury metal, which is cooled and recovered in a condensing system. Potential health and safety problems exist because mercury vapors can escape from the furnace and condenser. The Bureau of Mines and McDermitt

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How to Recover Barite from Waste Pond Materials

Table of ContentsGeorgia Waste Pond SampleNevada Waste SamplesWaste Pond SampleIllinois Waste Pond Sample A major goal of the Bureau of Mines is resource conservation, which includes (1) maximizing mineral recovery from domestic resources and (2) recovering mineral values currently lost in scrap and waste materials. To help meet this goal, the Bureau of Mines has been investigating the recovery of

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Aluminum Extraction by HCl and Fluoride Leaching

Table of ContentsEquipmentSingle-Stage LeachingCocurrent LeachingCountercurrent Leaching The United States depends on imports of bauxite and alumina for most of its aluminum requirements. To reduce this dependence, the Bureau of Mines conceived a raw materials-process technologies matrix as a means of systematically investigating the technology options available for processing domestic aluminum resources. In 1973, a research program was initiated based on

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Chemically Bonded Refractories

Table of ContentsChemical BondingPhosphate BondPhosphate Bonding AgentsFundamental StudiesProperties of Phosphate-Bonded MaterialsSilicate BondAlkali SilicatesEthyl SilicateOxychloride, Oxysulfate, and Oxynitrate Bonds Improved ceramic materials are in constant demand for processes involving severe chemical, corrosive, and thermal environments, especially at high pressures. During the past decade, demand for higher quality ceramic materials has significantly increased. This is true, for example, in the steel industry

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Effect of Sodium Chloride Leach on Copper Chalcopyrite

Table of ContentsMaterials and EquipmentExperimental ProcedureResults and DiscussionBaseline ExperimentNaCl-Aided Experiment As part of the mission of the U.S. Department of the Interior’s Bureau of Mines to help insure the continued viability of the domestic minerals and materials economy, and to help maintain an adequate minerals base, research was conducted to investigate in situ leach techniques for extraction of copper from

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Recover PGM by Matte Smelting and Leaching

Table of ContentsExperimental Procedure and EquipmentInduction SmeltingGrindingLeachingRoastingSample AnalysisResults and DiscussionMatte SmeltingSynthetic Matte SmeltingStillwater Matte SmeltingMatte Species IdentificationPreliminary Matte-Leaching ExperimentsFirst-Stage LeachingAcid-to-Matte RatioParticle SizeTemperature and Duration of LeachLarge-Scale First-Stage LeachingPreliminary Second-Stage Leaching StudiesSecond-Stage FeCl3 or Fe2(SO4)3 Leaching of Synthetic MatteSecond-Stage FeCl3 or Fe2(SO4)3 Leaching of Stillwater MatteOther Leaching OptionsSequential Matte LeachingRoasting-Leaching of First-Stage ResidueSummary An important objective of Bureau of Mines research

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How to Remove Molybdenum Process Plant Water

Table of ContentsExperimental ProcedureExperimental ResultsEffect of Iron Compound TypeEffect of Iron-to-Molybdenum RatioEffect of Ferric Sulfate ConcentrationEffect of pHEffect of Agitation IntensityEffect of TemperatureEffect of Precipitator Retention TimeEffect of a Retention TankEffect of Two-Stage PrecipitationEffect of Additional FlocculationEffect of Flotation AirRecycle RateAir PressureEffect of Flotation Cell ThroughputFroth DewateringDeportment of Added IronSolids DisposalDemonstration RunsFlow Diagram and Economic Evaluation The minerals industry uses

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Acid Mine Drainage Treatment & Sludge Disposal

Table of ContentsProperties of Mine Drainage SludgePhysical PropertiesChemical PropertiesMethods of TreatmentRates of Sludge ProductionCurrent Disposal PracticesSludge Settling and RemovalSludge TransportationSludge DisposalSludge Settling and RemovalSludge TransportationSludge Disposal The technology of acid mine drainage (AMD) treatment has improved since the mid-sixties, and water pollution from active coal mining operations has been reduced considerably. Present treatment processes are designed to raise the pH

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