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Dithiophosphate in Selective Flotation of Galena and Sphalerite Using CuSO4 and NaCN
Dithiophosphate collectors are commonly used in the flotation of sulphide minerals. Studies of the interaction of a typical dithiophosphate collector with galena surfaces have been previously reported from these laboratories. These fundamental studies were carried out by employing phosphorus labeled radioactive dithiophosphate. Radioactivity determinations then could be used to measure readily and accurately the small concentrations of dithiophosphate that, are
Self-diffusion in Sintering of Metallic Particles
Table of ContentsEvaporation and CondensationVolume DiffusionExperimental Method Two particles in mutual contact form a system which is not in thermo-dynamical equilibrium, because its total surface free energy is not a minimum. If such a system is left for a certain period of time, the bonding of the two particles will take place in order to decrease the total surface area,
Placing Concrete in a Deep Mine
In U. S. underground mines concrete work is not widely used. Timber and steel are cheaper, and there are few serious water problems. But in the Union of South Africa men dig deeper, more persistently, and probably more profitably than anywhere else on earth. Some gold mines near Johannesburg are below the 10,000 level and employ as many as 35,000
Ball Mill Shell Liner Performance
Grinding Practice—These tests were run in the 9 ft diam by 8 ft long grate discharge ball mills at Climax. Each mill functions in closed circuit with a 78 in. Akins duplex high-weir classifier, and a circulating load of 300 pct is maintained. The size of the mill feed is 6 pct on 3/8ths, which is ground to pass 28
Mine Ore Mining Methods
Iron king mine, producing gold-silver-lead-zinc ore, is 10 miles east of Prescott, Ariz. At present the 1806 level is being developed. The echelon pattern of ore deposit continues at depth but is less pronounced, and the orebody is now more or less continuous over 2600 ft of strike length, with widths 5 ft to as high as 26 ft where
Humphreys Spiral Concentrator
Table of ContentsHumphreys Spiral Concentration of Iron OreThe Cleveland-Cliffs Iron Company PlantSpiral Plant Operation and PerformanceGrindingSpiral Concentration Since it was introduced in 1943 to recover chromite from Oregon beach sands, the Humphreys spiral concentrator has proved successful in several fields of wet mineral beneficiation. By the end of 1957, 9390 Humphreys spirals had been manufactured. Most of these are still
Mineral Flotation with Ultrasonically Emulsified Collecting Reagents
An emulsion is a two-phase system consisting of two incompletely miscible liquids, the one being dispersed as finite droplets in the other. The dispersed liquid is known as the internal or discontinuous phase, and the surrounding liquid is termed the external or continuous phase. Apparatus and Experimental Procedure: Ultrasonic emulsification was performed in three steps, although a one-step method has been
Dry Magnetic Cobbing Separation
Table of ContentsEquipmentFlowsheetsCapacities of CobbersSpeed and Strength of Magnet vs. Size of Material being TreatedMetallurgical Problems Cobbing, as used in this paper, refers to coarse dry magnetics separation. It is applicable when, by its practice, plant cost can be reduced or the value of its products increased by the removal of a barren or lean reject or a high grade
Belt Conveyor Design
Idlers: Due to the efforts of the Conveyor Equipment Manufacturers Association, the basic idler elements—idler roll wall thickness, bearing sizes and shaft sizes—have been standardized into classes. There is also a substantial dimensional commonality as well. Belting: Again, the rubber manufacturers have standardized, either by agreement through industry associations, or by following the leader and providing competition. Smaller belt conveyors
Aerofall Mill Liner Design
Table of ContentsShell LinersEnd LinersInner Deflector LinersOuter Deflector and Ring LinersWhy the Aerofall Mill is Unique in the Comminution FieldDetailsPebble Mills Using Composite Pebble and Ball ChargesAll-Pebble Mill Plant with Single Stage GrindingEconomic Application of Pebble Mills in the North American EconomyBasic New Principles Incorporated in the Aerofall MillAerofall Mill Application According to the manufacturer, a distinctive feature of the
Contact Angles Adsorption Density Zeta Potentials and Flotation Rate
The object of this article is to point out the experimental relationship which exists among contact angle, adsorption density, zeta potential, and flotation rate data. In each of the experiments discussed in this article, the surface properties of quartz, as a function of pH, were measured in solutions to which constant quantities of dodecylammonium acetate were added. The pH of
Earthquake Design for Metallurgical Plants
Table of ContentsPrincipal Earthquake AreasMagnitude Acceleration Strong MotionMinimum Design Considerations and CostGeneral Design ConsiderationsSiteFoundationsConcreteStructural SteelProcess Equipment All persons and communities that have experienced strong-motion earthquakes are convinced of the importance and complexity of earthquake problems that must be solved in order to reduce the personal hazards and property losses to a reasonable minimum. It is also clear that absolute elimination
Analyzing Ore Reserves: Statistical Method of Calculating
There are certain data handling techniques used by statisticans that can help one to calculate the size of an orebody and to develop some of the relationships between size, cutoff grade, average grade, mining cost, and profit. Knowing the relationships amongst these factors can help determine the most desirable operating conditions. A statistical technique that we will use is data
How to Measure the Tensile Strength of Rocks
Principle and equipment are the same as for the test for tensile strength of hydraulic-cement mortar. The test specimen has the shape of a briquet. While in the original cement mortar test the briquet is cast in a special mold, it is prepared from rocks in different ways, depending on how easily they can be cut and shaped. Soft rocks,
Cement Grinding Plant Design
Grinding is a large and costly part of Portland cement manufacture. Prior to clinkering in the rotary kiln, raw materials are ground to a fineness of 80 to 90 pct passing 200 mesh. Then, after burning and cooling, the resulting clinker is ground to about 92 pct passing 325 mesh. Open Circuit Clinker Grinding: Many early clinker grinding plants employed
Molybdenite Leaching Kinetics
High temperature-high pressure techniques have long been used to great advantage in the organic chemical industry, the petroleum industry, and the paper industry. Only recently, however, have these methods been used to extract metals from their ores on a commercial scale. The Chemical Construction Corp., together with interested producers of nickel and cobalt, has done much to develop methods of
Comminution: Energy-Size Reduction Relationships
Search for a consistent theory to explain the relationship between energy input and size reduction in a comminution process has accumulated, over the years, an enormous amount of plant and laboratory data. Although some correlation of these data has been possible for purposes of engineering design and for the advancement of research in fracture, there is still great need of
Lime Burning Operation Heat Energy Requirements
Table of ContentsMarketing and UsesPaper ManufacturePrice History There are two types of lime, high calcium and dolomitic lime. Typical analyses of these materials are shown in Table 1. This discussion is concerned only with high calcium lime. Lime is produced from naturally occurring limestone by subjecting the limestone to a temperature in the range of 2200°F for sufficient time to
Phosphate Rock
Table of ContentsUses of PhosphateManufacture of ProductsFlorida Pebble FieldTennessee FieldOther Deposits in United StatesMoroccoAlgeria-TunisiaRussian DepositsWorld Production of Phosphate Rock Apatite, the most abundant crystalline phosphate mineral, is found in igneous rocks and probably is the primary origin of all other phosphates, whether mineral or organic. Its chemical formula may be expressed as Ca5(Cl,F) (PO4)3. The chlorine may be replaced almost
Block Caving Mining Method
Table of ContentsSlusher Drift DevelopmentUndercutting TechniqueSlusher Drift Forms Block Caving has been developed to a high degree of efficiency in the last two decades and more particularly since World War II. At the Jeffrey mine of Canadian Johns-Manville Co., in the Eastern Townships of Quebec, several innovations have increased production and decreased costs. Asbestos ore is produced at the rate
Nitrates and Nitrogenous Compounds
Table of ContentsNatural Nitrate DepositsOccurrenceProspecting and Mining PracticeExtraction of Nitrate and Preparation for MarketExtraction of IodineCoke By-Product NitrogenRecovery of By-product Nitrogen Chemical nitrogen and the “nitrates” of commercial significance are derived mainly from three basic sources: (1) the natural deposits in the form of nitrate-bearing earth and clay, which, being largely water-soluble, can exist only in the most arid portions
Solvent Flooding
Table of ContentsDescription of Oil Recovery ProcessDisplacement Studies in which Complete Miscibility is Maintained at all TimesDetermination of Concentration Profiles in the Mixing ZoneDisplacement of LPG by Natural Gas Under Conditions of Partial Miscibility Core Systems UsedCharacteristics of Miscible Fluid-Mixing ZonesEffect of Displacement Rate on Miscible Fluid-Mixing ZonesApplication One-third to one-half of the original oil is left in most reservoirs even
Grinding with Low Speed Under-Loaded Ball Mill
The small ball mills and rake classifiers in the London concentrator were replaced by one large ball mill and one hydraulic classifier. This new ball mill was designed oversize so that it could be operated at slower than normal speed. The proper operating conditions were established and the results published. In 1953 this study was reopened when plans were made
Morenci Reduction Works – Milling Practices
Table of ContentsOrePrimary CrushingSecondary CrushingGrindingFlotation and Regrinding of ConcentrateFiltration of ConcentrateWater Supply and ConsumptionTailing Disposal The Morenci concentrator of the Phelps Dodge Corporation is a part of the project that was completed after five years had been spent in development of the open-pit mine, equipment and process testing in the former No. 6 concentrator, and construction of the reduction works.