Blogs
High Temperature Electrostatic Precipitator
Table of ContentsEquipmentProcedureOperationsResultsDiscussion Industrial precipitators utilizing negative corona operate at maximum voltage to attain highest efficiency in removing finely divided particles from gas streams. Usage, however, is limited to applications at temperatures to about 1,000° F. Therefore, in conjunction with other work for processing coal at high temperatures, the Bureau of Mines sought to extend the applicability of precipitators for
Small Particle Size Minerals Magnetic Separation
Table of ContentsBasis of DesignMagnetization Time and Field IntensityMagnetization Time and Separation SelectivityUtilization of Particle MomentumProcedure and ResultsConstruction DetailExperimental ResultsRelative Effect of Various VariablesCondition 1Condition 2 By using the magnetization delay factor and the acquired momentum of the particle, minerals may be separated with magnetic susceptibilities within the diamagnetic susceptibility range. Unlike the rotating drum of the induced roll separators
Method for removing aluminum from diecast scrap
Table of ContentsSystem 1— FeCl3 + NaClTheoretical ConsiderationsExperimental Procedure and EquipmentResultsAlternate ProcedureSystem 2—Fe2O3 + CaCl2 + NaClSystem 3-Spent Sal SkimmingsTheoretical ConsiderationsExperimental Procedure and EquipmentResults Zinc-base die-cast scrap represents the largest single source of secondary zinc. A large part of the die-cast scrap originates from grills, fuel pumps, carburetors, trim, and hardware from scrapped automobiles and other machinery, or from punchings
Joining Refractory Metal Compounds by Hot Pressing
Table of ContentsCharacter of Materials and ProductsAnalyses of Starting MaterialsSpectrographic and Gaseous ImpuritiesCompound IdentificationParticle-Size DistributionPycnometric DensityVacuum-Hot-Pressed ProductsPhysical and Mechanical PropertiesBulk DensityThermal ExpansionThermal-Shock ResistanceStrengthChemical PropertiesMelting PointOxidation BehaviorCompatibility of MaterialsCold-Pressed and Vacuum-Sintered BodiesVacuum-Hot-Pressed BodiesX- Ray Diffraction and Metallographic ExaminationsFifty Percent ZrC + Fifty Percent ZrNFifty Percent ZrN + Fifty Percent ZrB2Fifty Percent ZrC + Fifty Percent ZrB2Fabrication of Graded JointsPrefabrication of Joint
Induction Melting of Titanium
Table of ContentsDiscussionDescription of EquipmentMelting Procedure and Results The primary purpose of the research covered by this report was the development of a method for induction melting titanium in a water-cooled copper crucible. The results reported represent findings obtained during the melting of a minimum number of ingots; therefore, only tentative conclusions can be drawn regarding the effects on metal
Recycle & Recover Titanium Chlorination Residues
Table of ContentsExperimental Procedure and ResultsLeachingChlorination Approximately one-half of the weight of the sludge generated in the commercial production of purified TiCl4 from rutile can be recycled with a coincident diminution of waste disposal problems and the more efficient utilization of TiO2 and carbon in the processing operation. The sludge can be separated into soluble and insoluble fractions by water
Drillability – Percussion Drilling
Table of ContentsPhysical Properties of Rocks DrilledResults and DiscussionEffects of Thrust on Penetration RateEffects of Operating Air Pressure on Penetration RateRelationship Between Physical Properties and Penetration Rate Penetration rate is increased by an increase in applied thrust up to an optimum point after which penetration decreases until the drill eventually stalls. Higher operating pressures result in increased penetration rates with
Ferrous Iron Oxidation by Activated Carbon
Table of ContentsAcknowledgmentsExperimental ProcedureTest Results The exploratory tests conducted with activated carbon and a ferruginous acid mine water indicate that ferrous iron oxidation takes place catalytically at an extremely rapid rate. The brevity of this study did not allow defining the reaction kinetics, or resolving the various factors affecting the activated carbon-air-acid mine water system. The favorable preliminary results warrant
How to Dismantle Junk Cars for Scrap
Table of ContentsComposite AutomobileDismantling StudiesRecovery and Value of Metals in the Composite CarFerrous Components and ValuesNonferrous Components and ValuesPostulated Scrap Yard OperationsCost Evaluation The proposed complete dismantling of the car removes all copper-containing parts; hence, the bales prepared from the clean ferrous metals should contain only the 0.07 percent copper that is in solid solution in the steel. As the
How Mercury Flows in Porous Media
Table of ContentsTheoryClear ChannelsPorous MediaExperimental Procedure and Results After studying the factors which influence oil recovery from petroleum reservoirs and since the flow behavior of fluids in petroleum reservoir rock depends to a large extent on the properties of the rock, techniques of core study that yield new or additional information on the characteristics of the rock would contribute to
Dispersion Strengthened Copper
Table of ContentsCoprecipitationAir Firing and Hydrogen ReductionPressing and SinteringExtrusion and SwagingTensile and Hardness MeasurementsStress-Rupture MeasurementsElectrical ConductivityDensity In accordance with a program for developing new materials required for emerging technologies, an investigation was undertaken to determine the properties of dispersion-strengthened copper. The copper contained either alumina or yttria as a dispersoid and was prepared by coprecipitation-a potential method for commercial production.
Solvent Extraction of Nickel and Zinc
Table of ContentsMaterials and ProceduresChemistry of the ExtractionsEquipment and ProcedureReagentsExperimental ResultsInvestigation of Solvent- Extraction VariablespH of Aqueous PhaseContact TimeOrganic/Aqueous Volume RatioSolvent ConcentrationTheoretical Extraction Stages RequiredContinuous, Countercurrent Extraction and Recovery of Zinc and NickelSolution ASolution B, Test 1Solution B, Test 2Solvent LossRecovery of Phosphate and Nitrate from Final Raffinate Solvent extraction of a waste solution from the phosphating of automobile bodies
Scrap Tire Distillation
Table of ContentsAcknowledgmentsDescription and Analyses of Raw MaterialsEquipment and ProcedureResults and DiscussionYields of Carbonization ProductsResidueGasHeavy OilsLight Oils Destructive distillation was demonstrated to be a technically feasible method of disposing of and obtaining potentially valuable products from scrap automobile and truck tires. The relative amounts of the various products were shown to be highly dependent on the temperature of carbonization. Highest
How to Stabilize Uranium Tailings
Table of ContentsAcknowledgmentsEnvironmental ConsiderationsDetermination of Stabilization ApproachChemical TestingOnsite Application of ChemicalsObservation of ResultsCost of Treatment An environmental radiological survey was conducted on the El Paso Natural Gas Co. uranium tailings pile at Tuba City, Ariz., in May 1967, by the South-western Radiological Health Laboratory of the Public Health Service, U.S. Department of Health, Education, and Welfare (HEW). As the abstract
Silver Chloride & Silver Bromide Thermodynamic
Adequate values for the standard heats and entropies of formation of silver chloride and silver bromide are available. However, thermodynamic calculations involving these substances have been hampered by the lack of accurate high-temperature enthalpy and entropy data. The enthalpy and heat capacity results reported in the literature are fragmentary and conflicting. As part of a Bureau of Mines heavy metals
Recover Metals from Electroplating Wastes
Table of ContentsComposition of WastesExperimental Procedures and ResultsWaste-Plus-Waste Treatment MethodOther Waste-Plus-Waste Combinations The waste-plus-waste treatment method can be successfully used on a variety of acid and alkaline electroplating wastes. The method is economically attractive because of the low cost of the waste-plus-waste addition step: No additional reagents are necessary, and the metal values are concentrated. In the five waste-plus-waste combinations
Convert Hydrous Calcium Sulfate to Hydrogen Sulfide
Table of ContentsMaterials and MethodsSulfate SourcesMediumBacteriaFlask StudiesFermentor StudiesResults and DiscussionEffect of pHEffect of TemperatureCarbon Source StudyMedium Exchange RateEffect of Sweeping Gas Upon Hydrogen Sulfide ProductionEffect of Hydrous Calcium Sulfate Solubility Upon Hydrogen Sulfide ProductionFermentor Design During the period 1960-65 sulfur consumption in the United States rose 40 percent to 7.96 million long tons. Since 1963, while demand has exceeded production,
How to Measure Surface Tension of Molten Metals
Table of ContentsCapillary PreparationBubble Chamber We been performing research on soft soldering with the objective of improving the strength of solder joints at elevated temperatures and pressures. Surface or interfacial phenomena and the factors affecting these phenomena are of major importance in soldering and brazing. A knowledge of the surface tension of the molten materials involved, such as the filler
Chalcocite Oxidation Roasting
Table of ContentsUnpelletized ConcentrateRaw MaterialsCold Tube FluidizationHot FluidizationExperimental Work—Pelletized ConcentratePelletizingDrum Kiln TestsContinuous Fluid-Bed Roasting The Bureau of Mines Twin Cities Metallurgy Research Center is engaged in a study to uncover a cleaner, more direct pyrometallurgical process for winning copper from sulfides. The .initial target is low-sulfur concentrates containing primarily chalcocite (Cu2S). Development work, still in progress, points to a new
How to Evaluate Face Respirator Fit
Table of ContentsDescription of MethodMeasurementsDiscussion For the past few years there has been increasing interest among respirator users in determining quantitatively the degree of protection afforded by protective respiratory devices. Overall protection depends on both the efficiency of filters and/or sorbents used and the tightness of seal around the edges of the facepiece. The Bureau of Mines first introduced quantitative
Recover Mercury by Electrolytic Oxidation
An aqueous oxidation treatment process developed by the Bureau of Mines has been shown to be effective for treating carbonaccous gold ores to improve gold recovery. Ozone, chlorine, sodium hypochlorite (NaOCl), and calcium hypochlorite [Ca(OCl)2] were all shown to be effective reagents for oxidizing the carbonaceous material in the ore. However, generation of oxidizing conditions in the ore pulp by
Tungsten Metal & Tungsten Carbide Electrolysis
Table of ContentsExperimental ResultsDirect Electrowinning of Tungsten Metal From WolframiteElectrowinning of Tungsten Metal From Wolframite Via Two-Phase ExtractionElectrodeposition of WC from Wolframite A high-temperature, two-phase extraction technique has been developed for the recovery of tungstic oxide (WO3) from tungsten-bearing minerals. The technique consists of dissolving scheelite (CaWO4) or wolframite in a system of two immiscible liquids-sodium chloride and sodium silicate-at
Ion Exchange Resin to Recover Gold from Acid Solution
Table of ContentsEffect of HCl and HNO3Effect of Common MetalsUse in Alkaline Cyanide SolutionsIon Exchange Resin-Loaded Papers for Analytical Use An ion exchange resin was found to quantitatively and selectively collect gold from acid solutions over a wide range of acid concentrations. Common metals at high concentration are not collected by the resin and they do not seriously interfere with
Recover Aluminum by Electrowinning
Table of ContentsCell AssemblyChlorine Recovery SystemCell OperationCurrent DensityTemperatureElectrolyte CompositionCell AtmosphereMetal Quality During OperationAnode-Cathode DistanceSummary of OperationEvaluation of Cell Construction Materials The preparation of aluminum by molten salt electrolysis of AlCl3 was undertaken as part of the Bureau of Mines overall research program to develop methods for the utilization of domestic low-grade raw materials, de Beauchamp and Thomas and others summarized