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Hydrochloric Acid Leaching Trisodium Phosphate, Zinc, and Iron from Sludge
Table of ContentsMaterialsPhosphate SludgesSolventsChemistry of ExtractionsExperimental Procedures and ResultsAutomobile SludgeDissolution and Extraction of Iron and ZincTrisodium Phosphate ProductAppliance SludgeDissolution and Iron ExtractionZinc ExtractionDiscussion As part of its solid-waste research, the Bureau of Mines is engaged in a broad program to develop low-cost processes for recovering and recycling metals and minerals from a variety of industrial wastes. One benefit is the
How to Reduce Surface Hot Shortness of Copper Bearing Steels
Table of ContentsExperimental ProcedureIsothermal Scaling StudiesGeneral Scale ZonesOcclusion of Copper by ScaleSimulated Ingot Heating Studies of Copper Steels Containing SiliconBorax Coating Studies The use of controlled steel silicon content or the application of borax coatings showed promise in preventing molten copper from forming on the surface of steels containing up to 1 pct Cu when these steels were heated to
How to Recover Aluminum & Precious Metals from Electronic Scrap
Table of ContentsRecover Aluminum & Precious Metals from Electronic ScrapElectronic Aluminum ScrapThree-Layer Electrorefining ProcessApparatusCompartment Electrorefining ProcessApparatus Our Solid Waste Program is directed toward three main areas of research: (1) Extraction of mineral, metal, and energy values from urban refuse; (2) recovery of mineral and metal values from wastes generated in the industrial utilization of raw materials and mineral-base products; and
Extraction of Manganese by Leaching
Table of ContentsMaterials UsedGeorgia UmberLeach LiquorsExperimental WorkCocurrent ExtractionPurification of Pregnant Leach LiquorsChemical PrecipitationIon ExchangeAutoclave DigestionAir OxidationOther Exploratory TestingCentrifuge Tests Demand for manganese continues to grow, but essentially all manganese used in the United States is imported. Although large deposits of low-grade manganese minerals are located in this country, domestic manganese producers have been unable to compete with the foreign ore
Recovery of Silver and Mercury by Electrolytic Oxidation
Table of ContentsMaterials and ProceduresResults and DiscussionElectrooxidation of Unionville TailingsElectrooxidation of Austin TailingsElectrooxidation of Zacatecas TailingsRecovery of Silver and Mercury From the Pregnant Solutions Silver was one of the first metals known to man, and metallurgical processes for the recovery of silver from ores date back into antiquity. Mercury amalgamation and retorting to recover metallic silver from slags, mine tailings,
Drop Weight Impact Tester
Table of ContentsTheoretical ConsiderationsInterpretation of Force-Time ProfilesExperimental ApparatusDrop TesterForce GageReaction Detection InstrumentationExperimental StudiesForce-Time ProfileExplosivesTime-to-Reaction DataData ReproducibilityEnergy and Pressure DataExplosive Thickness Effect For many years, the impact test has been one of several techniques used to determine explosive sensitivity. This test has provided a useful index having practical value; however, it provides only an ordering of the sensitivities of a series
Electrically Leach Molybdenum by Oxidation
Classic flotation and roasting procedures for recovering molybdenum oxide from molybdenum source materials frequently result in low recovery of molybdenum. This is particularly true in molybdenum flotation from porphyry copper ores where difficulties can he encountered in refloating molybdenite which has been recycled to rougher and cleaner flotation sequences. Because copper-molybdenum separation may be less than desired, a portion of
Impact Crushing Size Distribution
Table of ContentsExperimental ProcedureAnalysis of Size DistributionCalibration of Screen AnalysesExperimental ResultsSize ReductionReproducibilityEffect of Velocity of ImpactEffect of Sample SizeSize Reduction as Function of Input Energy and Initial Particle SizeSize DistributionEvaluation and Interpretation Although the comminution process has undergone much experimental study, there is not yet an adequate theoretical basis for predicting the mean size and size distribution of the product
Extraction Process Sm2O3 Samarium Leaching
Table of ContentsEvaluation of Strip SolutionsEffect of NH4Cl Concentration on Mass Transfer and SeparationEffect of Organic Diluent on Mass Transfer and SeparationEffect of pH on Mass Transfer and SeparationTemperature Effect on Sm/Nd SeparationCountercurrent Mixer-Settler Studies The growth in demand for certain lanthanides has resulted in the development of industrial processes for their separation and purification from source materials. These operations
Electrowinning of Titanium
Table of ContentsCircular 12-Inch-Diameter CellSolid Materials Composite DiaphragmsLoose Fill Materials Composite DiaphragmsRectangular Cell Composite diaphragms were constructed and used for the electrowinning of Ti from TiCl4 to eliminate some of the problems associated with diaphragm failure. High-purity titanium (Ti) was previously electrowon from titanium tetrachloride (TiCl4) fed into a molten electrolyte (520° C) composed of lithium chloride, potassium chloride, and
How Pipe Geometry Affects Flow Velocity & Head Loss
Table of ContentsExperimentationSolid ParticlesApparatusExperimental ProceduresResults and AnalysesDelivered Solids ConcentrationData Presentation and InterpretationMathematical Representation and Pipe Shape FactorMinimum Carrying VelocityCharacteristicsDetermination and ComparisonHead LossSeparation of Slurry Head LossComparison of Clear Water Head Loss Using Darcy’s EquationComparison of Solids Head Loss Using Durand’s EquationHead Loss RatioSolids Head Loss of Circular Pipe and Noncircular PipeReduction of Slurry Head Loss Transporting solids in pipelines generally
Leach Gold by Sodium Hypochlorite / Chlorine & Electrolytic Oxidation
Table of ContentsMaterials Equipment and ProceduresResults and DiscussionOxidation by NaOCl AdditionOxidation by Chlorine AdditionElectrooxidation The extraction of gold from ores that contain carbon and organic compounds has presented a problem to the cyanide mill operator ever since the widespread adoption of this classical dissolution technique in the late 1800’s. The problem was studied in 1924 by Leaver and Woolf. More
Classification Solid and Liquid Oxidizers
Table of ContentsProposed Burning Rate Test for Solid OxidizersProposed Ignition Hazard Test for Liquid OxidizersClassification of Oxidizers by Proposed Test Methods We recently prepared recommendations on methods of evaluating and classifying flammable liquids and solids for use in government transportation regulations. This report is the third in this series and describes the classification of oxidizing materials which are defined in
Classification Flammable Solids
Table of ContentsProposed Method for Flammable SolidsProposed Method for Extremely Flammable SolidsClassification of Flammable Solids by Proposed Test Methods The Bureau of Mines research programs are partly directed to developing safety guidelines for the reduction of fires and explosions in industries that produce, transport, or utilize mineral fuels and their products. As a result of a request by the Department
Bin Hopper Flow Design & Engineering
Table of ContentsReview of the Empirical ApproachFlow-No Flow CriteriaFlow Rate FormulasFlow Regime ConsiderationsCritique of the Empirical ApproachReview of the Phenomenological ApproachFlow-No Flow CriteriaFlow Rate FormulasFlow Regime ConsiderationsCritique of the Phenomenological Approach A detailed Bin Hopper Flow Design & Engineering Study: The mining industry in the United States alone produces nearly 4 billion tons of new bulk materials annually that has
Photoelectric Charging & Electrostatic Separation
Table of ContentsPhotoconductivity Versus Photoemission of ElectronsUltraviolet Light Absorption in AirPhotoemission Effects of Conductive MineralsPhotoemission from Dust-Size ParticlesCharge Required for Dust Separation Electrostatic separation is used when froth flotation fails, such as with oxidized ores, or where there are similarities in response with magnetic and gravitational methods, or when the use of water is to be avoided. Theoretically, for fine-size
Effect of Preheating Iron Ore Pellets
Table of ContentsRaw MaterialsProcedure and EquipmentPelletizingExperimental WorkEquipmentResultsOxidation of MagnetiteSinteringEffect of Preheating Upon MetallizationEffect of Preheating Upon Pellet Properties The production of pre-reduced iron ore pellets involves the expenditure of considerable capital and energy. Both prereduced and oxide pellets can be produced in similar equipment by using reducing and oxidizing processes, respectively. However, the throughput for a 5-m-ID by 50-m-long kiln
Electrodynamic Separator
Table of ContentsSample TestedApparatus and Procedures Used Several years ago, the Bureau of Mines initiated a program to develop effective methods for reclaiming and recycling metal and mineral values contained in urban solid waste. The Bureau’s initial work at its College Park (Md.) Metallurgy Research Center dealt with establishing reliable methods for sampling and characterizing the residues left from the
Applied Mining Geology
The geologic notes are taken as soon as possible after the ground is broken so that any mistake in the mining may be corrected at once, or any particularly advantageous procedure may be suggested before any useless work is done. Taking the notes underground is a comparatively simple matter, but a few necessary precautions may be pointed out. The essential
Small Scale Metal Recycling Plant & Equipment
Table of ContentsTechnical ConsiderationsFlowsheetPilot Plant PerformanceProduct UtilizationProcess EconomicsFuture Plans Of the 220 million tons of refuse collected annually in the United States, it is estimated that about 30 million tons are incinerated, generating about 7 million tons of residues. In previous work, the Bureau of Mines developed a continuous mechanical process capable of converting 85 percent of municipal incinerator residues
How to Remove Pyrite from Coal
Table of ContentsDry-Separation ProcessCentrifugal SeparationElectrostatic SeparationGrindability of Pyrite and Coal-An Aid in SeparationCombined Centrifugal-Electrostatic Separation In recent years, coal research has been directed toward environmental problems of the electric power generation industry. A major problem of coal-burning power-plants is reducing the air pollutants in stack gases. In most of these plants, the chief pollutant is SO2, which results from the
Precious Metals – World’s Top 10
Ever wondered why people keep their gold pieces in safes? And why your family silverware is always so well protected? Well, that’s obviously because gold and silver are two precious metals. That you already know… But what about other metals? There are other substances equally precious, even more, precious than gold, that you must get to know better. So here’s a
How to Separate Copper from Scrap by Melting
Table of ContentsAcknowledgmentsLaboratory EvaluationExperimental ProcedureSweating With Other Predip TreatmentsElectronic Component SweatingDiscussion and Concluding RemarksCost EstimateDescription of ProcessesEstimating MethodCapital CostsOperating CostsEvaluation, Results, Discussion, and Conclusions The secondary metals industry has been a major segment of the domestic economy for years. Many secondary commodities (heavy melting steel and lead storage batteries are familiar examples) have become so well established and recycled so
Copper Smelting
Table of ContentsCopper Smelting ProcessHeat Balance Using Pure Oxygen Versus AirCopper Smelting Furnace Construction and Refractories UsedTest Procedure and Discussion of ResultsSlag Composition, Losses, and Forms of CopperAnalytical TestsInduction Furnace TestsFlotation Tests Throughout this century the major production of copper (as it relates to Copper Smelting) and most other nonferrous metals has been through pyrometallurgical methods, treating sulfide ores by