Blogs
How to Measure Flotation Cell Aeration
Present flotation processes depend almost entirely on the buoyant properties of air bubbles to effect separations of mineral and gangue, but there is no convenient method for measuring aeration in flotation cells. Consequently the relation between aeration and cell performance has not been definitely established. In connection with a comparative study of kerosene and froth flotation processes, a modification of
Black Sand Minerals in Gold Placer Deposit
Table of ContentsHistoryLocation and AccessibilityPhysical Features and ClimateDrillingLaboratory Procedure at Spokane, Wash.Laboratory Procedure at Albany, Oreg.Description of DepositSize of DepositGeneral GeologyMineralogyAnalytical Results This report describes work done as part of a Bureau of Mines program to appraise the titanium-mineral resources of Idaho. The work included both field reconnaissance and a spot churn-drilling program. Much general information was available, as a
Beryllium Determination
Table of ContentsExperimentalSample PreparationThe MethodAccuracy and Reproducibility The main source of beryllium in pegmatite is the mineral, beryl. Many of the conventional methods for the determination of beryllium in beryl are not suitable for control purposes because of lack of speed and accuracy, especially in the range below a few tenths percent. Beryl resists the usual chemical attack and can
How to Recover Mercury from Cinnabar Stibnite Ore
Table of ContentsConcentrationThe OrePhysical CharacterChemical CharacterProcedureResultsExtraction of Mercury from Cinnabar-Stibnite ConcentratePreliminary Roasting TestsTemperatureRetention TimeSpace RateGas CompositionAddition of Air to Exit GasesCondenser ProductsCondenser LossesContinuous-Roasting TestResults and ObservationsExtraction of Mercury from Cinnabar ConcentratePreliminary Roasting Tests Generalized conclusions cannot be drawn from the laboratory studies about the economic feasibility of extracting mercury by a combined flotation and fluidized-bed roasting process. The 94 percent
Ferric Chloride Trap
This paper discusses the design and use of the ferric chloride trap. The operation is simple and self-adjusting. The rock-salt column is self-cleaning and will remove ferric chloride, other impurity chlorides, and dust from gaseous titanium tetrachloride. The losses of titanium are low, and the molten mixture is easy to handle. The trap is placed in the hot gas stream
Crushing Granite
Table of ContentsExploration and Estimation of ReservesDevelopment and MiningGeneralRemoval of OverburdenPrimary Drilling and BlastingSecondary BreakageQuarry Loading and TransportationProcessingGeneralPrimary CrushingSecondary Crushing, Screening, and StorageBlending and LoadingMaintenance and RepairsAuxiliary OperationsSupervision, Engineering, and Office PersonnelLabor DistributionPower Distribution The quarry is located in the western part of the Piedmont Plateau. Geologically, this province is described by Watson as an area of highly metamorphosed sedimentary
How to Concentrate Mercury
Table of ContentsPhysicalChemicalConcentrationFlotationDistillationSummaryPhysicalChemicalConcentrationPhysicalChemicalConcentrationSummaryNature of OrePhysicalChemicalConcentrationNature of OrePhysicalChemicalConcentrationNature of OrePhysicalChemicalConcentrationDense MediumFlotationConclusions Most mercury ores are directly roasted or retorted for recovery of metallic mercury without preliminary concentration. Recoveries are high, often approaching 100 percent; the cost is nominal. The tenor of domestic mercury ores, however, has been dropping steadily, so that the estimated average heads are now about 0.35 percent Hg
How to Prepare Thin Rock Sections
Table of ContentsPreparation of a Rock Slice for MountingPreparation of Friable and Altered Hocks for MountingPreparation of the Glass Slide for MountingMounting Rock Slice on Frosted-Glass SlideGrinding Mounted Rock SliceMounting the Cover GlassThin-Section Smears of Loose Crushed Grains In this recommended method of preparing a thin section the operator begins by obtaining a rock slice approximately 1 inch in diameter
How to Make Chromium Metal – Metallurgy
Table of ContentsProduction Methods For Chromium MetalCarbon Reduction of Chromium OxideChromium by Dissociation of Chromium NitrideFusion ElectrolysisChromium from AmalgamDissociation of Chromium IodideChromium Oxide Reduction with MetalsHydrogen Reduction of the ChloridesChromium Chloride Reduction by MetalsReduction of Chromium Chloride with MagnesiumPurification of High-grade Chromium by Hydrogen TreatmentProduction of Pure Chromium from Chloride on a Commercial Scale Aluminothermic or silicothermic processes used for
Stone Cutting and Polishing
Table of ContentsCutting Rocks in the Quarry (2)Cutting and Finishing Stone in MillsLimestone (4)Marble (2)Sandstone (2)Granite (5)Slate (3)Cutting and Polishing Gems and Semiprecious StonesMaterials Used and Their Products (10) (16)Hardness of Ornamental StonesPrincipal OperationsSawingTypes of SawsSawing EquipmentGrindingLappingSandingPolishingPolishing BuffsPolishing AgentsPolishing OperationsDrillingCutting CabochonsCutting Faceted StonesCutting JadeCutting Quartz CrystalsTumblingSpecial Cutting ProcessesPrecautionary MeasuresLapidary Equipment and Supplies The mining and fabrication of structural and ornamental
Heavy Liquid Testing Procedure
Table of ContentsHeavy Liquid SeparationDescription of MaterialsOreHeavy LiquidApparatusProceduresExperimentalAnalyticalData EvaluationA Study of the Influence of Particle Size, Feed Density, and Feed PressureEffect of Particle SizeEffect of Pulp DensityEffect of Feed PressureInfluence of Feed Grade and PressureEffect of Feed GradeEffect of Feed PressureSelected Cyclone Parameters and Feed DensityEffect of Apex Opening SizeEffect of Vortex Finder SizeEffect of Pulp DensityMultistage Cyclone SystemsResults of
Fluorspar Beneficiation Process Plant
Table of ContentsThe Fluorspar Beneficiation ProblemA Fluorspar Flotation Process FlowsheetCrushing Fluorspar OreGrinding CircuitPulp ConditioningFluorspar FlotationThickening and FilteringDrying and StorageProduction of Acid Grade FluorsparThe Acid Grade Fluorspar ProblemThe Acid Grade Fluorspar FlowsheetCrushing CircuitGrinding CircuitConditioning TankFluorspar FlotationThickening and FilteringDrying and StorageDifficult Flotation of some Flourspar OreThe Difficult Metallurgy ProblemThe More Complex Treatment FlowsheetFATTY ACIDS IN FLUORSPAR FLOTATIONDesign Study for 125-Ton Fluorspar MillTin Process FlowsheetConcentrator SiteProcess Plant DesignFluorite
Refine Zinc from Iron Impurity
Table of ContentsPresent Practice for Removing Small Amounts of Iron from ZincMaterials TestedSegregation and Filtration StudiesSegregation TestsDescription of Small-Scale FilterExperimental Filtration ProcedureResults of Small-Scale Filtration TestsLarge-Scale Filtration TestCentrifugation StudiesDescription and Operation of the CentrifugeExperimental ProcedureResults of Centrifugation TestsRemoval of Residual Aluminum and Recovery of Zinc from Residues A process was developed in which iron-contaminated zinc was refined to readily acceptable
How to Recover Lead & Copper from Blast Furnace Matte
Table of ContentsBrine Leaching DevelopmentsMaterials TestedPreliminary Experiments and ResultsCyclic Leach of Matte AWater Leach SeriesBrine Leach SeriesCyclic Leach of Matte BWater Leach SeriesBrine Leach SeriesFinal Cyclic Leach of Matte BWater Leach SeriesBrine Leach SeriesDiscussion This research has shown that & solid waste byproduct from secondary lead smelters can be successfully processed to recover copper and lead that is lost during
Electrorefining Vanadium Scrap
Table of ContentsDescription of Equipment and ProcedureElectrolytic CellMaterialsOperating ProcedureExperimental InvestigationHeavy ScrapRefiningQuality of ProductLight ScrapRefiningQuality of ProductGranular ScrapRefiningQuality of ProductDiscussion A molten-salt electrorefining process was developed which provides a practical way for reclaiming vanadium from scrap generated in the processing of ductile vanadium into bar, sheet, wire, and other shapes. Refining produced extremely ductile vanadium with a purity range of 99.93
Ball Mill Pulverizing
Table of ContentsExperimental Test SystemTest ProceduresTest ResultsInfluence of Initial Moisture Content of LigniteIn-The-Mill DryingLignite SourceComparison of Results to Pulverization in a Test Hammermill As in a pilot-plant-scale hammermill, the effect of moisture content in the pulverization of lignite in a similar size ball mill was observed to be a highly significant factor with respect to power required and in pulverization
Fluorine Determination Method
Table of ContentsSpadns-Zirconium MethodAshing with a Fixative AgentSodium CarbonateCalcium OxideDistillation with Phosphoric and Sulfuric AcidsFluorine and Phosphorus in Float and Sink FractionsFluorine Determinations of Coals Coal normally contains trace amounts of fluorine ranging up to about 0.02 percent. These small quantities of fluorine generally are volatilized when coal is burned in boiler furnaces. but they may be a transient factor
Vacuum Arc Melting
Table of ContentsTheoretical Pattern of Heat Transfer from Ingot to Cooling WaterExperimental Procedure and ResultsNonconsumable Electrode Arc Melting StudiesConsumable Electrode Arc Melting StudiesExperiments with the 2-5/16-Inch-Diameter CrucibleExperiments with the 8-Inch-Diameter CrucibleEffect of Narrow Annular Spacing for Water JacketsDiscussionCrucible Wall ThicknessWater Jacket DimensionsConclusions During the past decade, several novel melting and casting techniques including vacuum arc melting, skull casting, Hopkins’ Process
Mining by Nuclear Explosives Fracturing
Table of ContentsHistory and Commercial Examples of In-Situ Copper Leaching MethodsCopper DepositsChemistry of Leaching CopperThe Effect of Bacteria on the Solubility of Copper Minerals and the Reaction of Bacteria to RadioactivityMechanics of LeachingNuclear ExplosivesPublic LiabilitySafety ProblemsAir BlastGround ShockRadioactivityRadiation Hazards to Off-Site EnvironmentRadiation Hazards to On-Site PersonnelContamination of CopperApplication of In-Situ Leaching to Nuclear Fractured DepositEconomics of Nuclear Fracturing and In-Situ
Gold Distribution & Variability in Drill Core
Table of ContentsPurpose of WorkMine Location, Geology, and ProductionExperimental DataHole DrillingCore Sampling and AssayingStatistical AnalysisFrequency DistributionsSources of VariabilityEstimation of Metal GradeAppraisal of Assaying The extreme variability in gold mineralization in drill core is revealed through the detailed sampling experiment. This variability is that naturally present on the smallest scale that can be found by fire assay. With samples of substantially
Electrowinning Rare Earth Elements
Table of ContentsCell Design and OperationElectrowinning NeodymiumElectrowinning PraseodymiumElectrowinning Didymium Electrowinning Rare Earth Elements like Neodymium, praseodymium, and didymium, were (obviously) electrowon from their oxides dissolved in fluoride melts. The use of a thermal gradient cell resulted in recovery of nodules of well-coalesced metal with a purity of 99.9 percent. Current efficiencies of up to 83 percent were obtained. Shallow immersion
Electrorefining Vanadium
Table of ContentsElectrolytic CellOperationPreliminary InvestigationsNaCl-VCl2 ElectrolyteLiCl-NaCl-VCl2 ElectrolyteBaCl2-KCl-NaCl-VCl2 and KCl-LiCl-VCl2 ElectrolytesLaboratory-Scale Production TestsElectrorefining in a KCl-LiCl-VCl2 ElectrolyteElectrorefining in a CaCl3-NaCl-VCl2 Electrolyte A molten salt, inert-atmosphere electrorefining process was developed for producing ductile vanadium from commercial vanadium. Five different chloride electrolytes were utilized. The chief impurity elements in the commercial vanadium were aluminum, iron, molybdenum, nitrogen, and silicon totaling 8 percent. Refining
Conveyor Belt Fire Hazard
Table of ContentsGallery TestsVentilating ConditionsIgnition SourcesPreliminary TestsMine TestsFire FightingResultsBelt IgnitionFlame PropagationExtinguishing Conveyor Belt Fires This investigation showed that neoprene, polyvinyl chloride, and rubber belts ignite readily when subjected to an impinging flame. Although pre-heating of the belt is not necessary for ignition, preheating does increase the probability of developing a self-sustaining flame after ignition. The time and total quantity of
Electric Smelting Lead Zinc
Table of ContentsTheoretical ConsiderationsSintering ExperimentsEquipment and MaterialsProcedureResultsDiscussionSmelting and Refining InvestigationsSmelting Equipment System and MaterialsProcedureResults of Water-Cooled, Condenser TestsResults of Molten-Metal, Splash-Condenser TestsSpecial Smelting InvestigationConventional Zinc Oxide SmeltingProcedure and MaterialsResultsEffect of Iron (Zinc Ferrite) on Recovery of Zinc MetalProcedure and MaterialsResultsEffect of Lead Oxide on Recovery of Zinc MetalProcedure and MaterialsResultsCombined Effects of Lead Oxide and Zinc Ferrite on the Recovery