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Sulfuric Acid Leaching of Smelter Matte
Table of ContentsMaterials and EquipmentLead Smelter MattesReagentsProcedureResultsDiscussionEffects of ReagentsEffects of Operating ParametersParticle SizeTemperatureAgitationCobalt, Nickel, and Copper RecoveryConclusions It has long been recognized that the 9 million tons of lead ore mined annually from Missouri’s Lead Belt (83 pct of the U.S. domestic production) contain significant amounts of nickel and cobalt. Yet, neither of these important commodities is being recovered by
Wet VS Dry Particle Size Analysis
Table of ContentsOperating PrinciplePhysical ConfigurationMicrotrac Analyzer The analysis of particle size distributions has become increasingly important in industrial processes. Particle size is recognized to be fundamental to the control of operations as diverse as grinding, crystallization, emulsification, agglomeration, and more. Particle size determination has traditionally been relegated to the laboratory, and is performed by slow, labor-intensive methods such as sieving,
Solvent Extraction Electrowinning VS Cementation: Copper Leaching
Table of ContentsMaterials and MethodsOre Sample DescriptionLeaching ProcedureCopper Recovery ProceduresExperimental ResultsLeaching the Coarse OreLeaching the Fine Ore In the commercial dump leaching of copper, two methods have been generally accepted as a means for recovering copper from pregnant leach liquors. The oldest and most widely used technique is copper cementation with scrap iron. The newer technique involves solvent extraction and
Laboratory Scrubber
Table of ContentsLaboratory Scrubber DescriptionLaboratory Test FacilityExperimental ProcedureDust SamplingDust Sampling AnalysisScrubbing Test Results The Bureau of Mines has funded an extensive research program to develop improved scrubbers for coal mine applications. This work shows that scrubbers can offer a highly effective technique for dust control during many mining operations. In the most recent applications, these scrubbers are usually mounted on
Hydroxyoximes
The kinetics of solvent extraction with hydroxyoximes are complex, involving mass transfer with chemical reaction in a heterogeneous system. One is therefore faced with a wide spectrum of possible behaviour within certain well defined boundary conditions. The extraction rate could be diffusion-controlled under all conditions and would thus depend on the interfacial area, and concentration of the slow diffusing species.
Temporary Emergency Replacement Mill Liners
Shell liners wear very fast in very large diameter autogenous and semi-autogenous mills. In addition to shell liner wear, the ends of the mill are susceptible to very high rates of wear, generally confined to fairly narrow bands. Due to the sheer size of modern mills, extensive downtime is required to replace shell liners or end liners. The inserted liner
How to Size a Water Spray Systems
Table of ContentsHow it Works Determine what diameter piping is necessary to obtain sufficient water flow to spray nozzles used for dust suppression. A simplified, diagrammatic method of calculating the flow of water through a proposed system consisting of a supply line and two banks of spray nozzles is outlined. How it Works The pressure versus flowrate of the supply at
Hot Rolling Metals in Vacuum
Table of ContentsMetal Hot Rolling EquipmentWhy Vacuum RollingBi-metalsAdvantages and Disadvantages of Using VacuumExperimental ProceduresDescription of EquipmentMechanical Reduction of Titaniumat Atmospheric Pressure and Moderate VacuumCladding by Rollins at Moderate VacuumHot Rolling EquipmentDiscussion and Conclusions Among the significant technological accomplishments of the third quarter of the 20th century was the wide application of vacuum-to-metal melting. Many of the more common metals, as well as
Heap Leaching Time
All metallurgical reactions are dependent on time, temperature, atmosphere (reducing or oxidising) and particle size. Particle size has been discussed and atmosphere will be discussed later. Temperature in heap leaching is dependent on ambient conditions and rates of reaction are not greatly effected during most of the year. Freezing in a northern climate or high altitude will impose operating constraints
Dry Grinding VS Wet Grinding
Table of ContentsEffect of Particle Size Distribution on Grinding Rate in Dry Ball MillingSize Distribution Effect The choice between wet and dry milling is, in general, unimportant in small-scale milling but is a major technical problem when large-scale milling in the metallurgical industries is involved. On purely mechanical grounds it is difficult to see any great difference in fundamental principles
Air Swept Mill
In an air-swept mill, the body of which does not differ significantly in general design from a trunnion overflow mill, a powerful stream of air is passed through the mill and removes the finer particles produced by the grinding process. This stream of powder-laden air is then passed through the classifier and the “oversize” material, rejected by the classifier, is
Grinding Aids
The general use of chemical grinding aids involving several different mechanisms for increasing throughput in the wet grinding of ores has been discussed in a number of recent publications. It appears from industrial scale testing that the use of selective dispersants with certain prespecified operating conditions is an approach which can produce two important results: first, increased feed rate at
Increase Plant Throughput by Mill Expansion
Table of ContentsMill Expansion ObjectivesExpansion Effects of Downstream Equipment Shortly after start-up, it was apparent that it would be difficult to obtain the plant design throughput. The ore sample that had been used for grinding test work was found to be much softer than that of the orebody in depth. This had led the designers to design without a crushing
Flux Lime
All forms of “lime” are used in the steel plant. Calcium hydroxide is used for water treatment, acid neutralizing, and as a lubricant for wire drawing. All the other limes are used as fluxes in the sintering plant, blast furnace or steel producing furnaces. In the production of self flux or super-flux sinter, high calcium and dolomitic limestone fines, are
Fluorocarbon & Hydrocarbon Collectors
Quartz did not float significantly at any pH value between pH2 and pH12 when any of the anionic collectors were used. The flotation of alumina with anionic collectors is depicted in figure 1. It can be seen that SOL functions as a good collector for alumina over most of the pH range studied, the recovery of alumina falling off only
Increase Uranium Recovery by Nitric Acid Leaching
Table of ContentsFlotation-Nitric Acid Leach ProcedureProcedure and ApparatusResults and DiscussionFlotationNitric Acid LeachingEffect of Amount of HNO3Effect of Particle SizeEffect of Time and TemperatureOffgas AnalysisNitrate LossesSolution Concentration and PurificationProposed Operating ConditionsEnergy and Environmental ConsiderationsConclusions To meet these uranium demands, larger, lower grade, and refractory ore bodies will need to be exploited. The utilization of these ores will require the development of
Flocculation Dewatering Clay
Table of ContentsDescription of Samples TestedInitial Testing of Reagents for FlocculationBench-Scale Batch Flocculation TestsTest ProcedureEffectiveness of Polyethylene Oxide PolymersSEM Examination of Flocculated SystemsTests on Plant WastesEffect of Solution ConcentrationEffect of Solids Content in Test FeedContinuous Flocculation TestsPreliminary TestsSmall-Scale TestsDescription of EquipmentMixing of Clay Waste and ReagentEffect of Trommel SpeedEffect of Trommel SlopeEffect of Reagent Concentration and DosageEffect of Clay-Waste Feed
Aluminum Sulfate Leach Solution Extracting Iron
Table of ContentsMaterialsEquipment and ProcedureResults and DiscussionDetermining Leaching ConditionsDetermining Extraction ConditionsDetermining Stripping ConditionsMultistage StudiesDetermining Alumina PurityConclusions Increasing usage of aluminum and competition for foreign reserves of bauxite have created a renewed interest in the development of domestic aluminum resources. Investigations were conducted into producing aluminum from domestic clays, anorthosite, and alunite in order to assure a continuing supply in the
Diamond Processing Plant & Equipment
World demand and production of diamonds both for gem and industrial purposes has increased nearly five-fold during the past 25 years. Improved mining and recovery methods together with the discovery and development of new fields has enabled mining operations to fill the growing demands. Producing areas in South Africa, South West Africa, The Congo Republic, Angola, Ghana, Tanganyika and Sierra
Batch Cyanidation Leach of Flotation Concentrate
The production of gold bullion from gravity or flotation concentrates is often an important economic consideration for an isolated gold mining operation. It is assumed in this case that the coarse free gold has been recovered by the Mineral Jig in the grinding circuit and that the jig concentrate has been amalgamated. This treatment produces a portion of the gold
COARSE FLOTATION
COARSE FLOTATION OFFERS IMPORTANT SAVINGS THROUGH REDUCED OPERATING COSTS Grinding cost varies greatly depending upon the size reduction required. For example, it takes approximately 50% less horsepower to grind from ½” to 48 mesh than it does to grind the same material from ½” to 100 mesh. Many minerals are liberated at a coarse mesh and middling particles often can
Placer Deposit Processing
The handling of large quantities of gold-bearing gravels is of utmost importance for most successful placer operations. In addition to providing efficient washing and recovery methods, the placer plant should be constructed as a compact unit that can be readily moved. This is an important consideration because the washing and recovery plant should be close to the mining area at
CHUTE SAMPLER
CHUTE SAMPLER FINDS WIDE APPLICATION ON DRY MATERIALS Many installations are confronted with sampler arrangements where the material is handled in chutes and installation of samplers either result in excessive dusting or substantial loss of headroom. The Chute Sampler is a compact, dependable automatic sampler unit which is ready for installation in a chute. Headroom loss is kept to a
Zinc Electrolysis
Table of ContentsZinc Chloride-Alkali Metal Chloride ElectrolytesProcedure & ResultsLiquidus Temperature DiagramsEffect of Electrolyte CompositionSludge Formation in ElectrolytesInternally Heated Electrolytic CellOperation of a 1,500-Amp CellConclusions Zinc Electrolysis was studied to help maintain an adequate domestic minerals base, the Bureau of Mines is investigating an aqueous chlorine-oxygen leaching procedure to produce ZnCl2 from sulfide concentrate and is also studying a fused-salt electrolytic