Blogs
Weighting Core and Cuttings in Diamond Drilling
A drill hole is bored in iron ore exploration principally to test variations in rock composition with depth and is usually directed as nearly normal to the bedding of a horizon to be tested as possible. This practice has a tendency to minimize variation in composition laterally which in any event is not likely to be great. It is obvious
Concentrating Tables
Table of ContentsBumping TablesDevelopment of Differential-Motion TablesPrinciples Of The Tabling ProcessSize and Shape of ParticlesImportance of Correct Operating ConditionsTable FoundationsEfficiency of Concentrating Table as Coal-Cleaning DeviceEvaluating Table Performance by Consideration of Washability CurvesConcentrating Tables vs. Other Cleaning Systems Wet-Process coal-washing tables as we know them today have been in use in this country for approximately 25 years. The literature records
High Tension Belt Conveyor Installations
Table of ContentsGeneral Belt Capacity ConsiderationsSelecting the High Tension BeltBelt SpecificationsIdler SelectionDrives The high tension belt conveyor is introducing a new and tremendously expanded era of low cost bulk material handling. High tension belt conveyors are generally those installations involving very long centers, high lifts, or drops, in which the belts are stressed up to their maximum tension values, and
Where to Find Gold
So tonight’s topic of interest is kind of near and dear to me, I’m going to start with the first slide; Rocks and Gold Clues. What rocks tell you about where to find gold, there are clues that they give and those are very important if you’re going to find gold and that’s what we’re here for; right? Hi, I’m
Dedusting and Dust Collection
Table of ContentsDedustingDust CollectionExhaust Hoods It is generally accepted that no method of coal cleaning except froth flotation is effective in cleaning dust. In the majority of coals mined in the United States the dust sizes contain a high percentage of impurities, hence the removal of the dust from the coarse sizes lowers the impurity content of these sizes. Dedusted
Alluvial Tin Mining
Table of ContentsHistoryOre OccurrenceProspectingDredging ConditionsDredging EquipmentOperating MethodsChinese Gravel Pump Mining A relatively small area in Malaya, about 200 miles long by 40 miles wide, is the most important source of tin in the world. Some tin is recovered in other parts of the peninsula. Of the tin mined, 98 pct is recovered from alluvial deposits. From 1935 to 1941 the
Metallurgical Slag pH Measurement
Table of ContentsParticle Size of Slag PowderEffect of Weight of Sample on pHStandard Technique used for pH MeasurementCorrelation of pH of Blast Furnace Type Slags with CompositionThe pH Method of Estimating Slag Basicity The correlation of the high temperature chemical properties of slag-metal systems with some easily measured property of either slag or metal at room temperature has been the
High Pressure Mercury Pump
When supplies of high pressure mercury or other liquids are required in analytical work, it is convenient to have the source of supply at a relatively constant pressure and available in sufficient volume to satisfy the requirements of the apparatus in use. Air enters the pump through the inlet port into the valve cylinder passes through the connecting tubing and
Quartz Flotation
Table of ContentsEffect of Size of Quartz on Pick-UpEffect of High Alkalinity on Pick-UpFlotation Tests On the basis of experiments conducted on quartz using a bubble pick-up method, it was shown in an earlier paper that this mineral will preferentially adsorb hydrogen, calcium, or sodium ions, depending on the relative concentrations of those ions in the solution in which the
Laboratory Measurement of Relative Permeability
Table of ContentsFactors which Influence the Measurement of Relative PermeabilityBoundary EffectHysteresis EffectProcedures and Results of Relative Permeability Measurements This paper presents the results of laboratory measurements of relative permeabilities to oil and gas on small core samples of reservoir rock by five methods, and describes the influences of such factors as boundary effect, hysteresis, and rate upon these measurements. The
Flotation – Gibbs Adsorption Equation
The technique of concentrating valuable minerals from lean ores by flotation depends upon the creation of a finite contact angle at the three-phase contact, mineral-water-air. If the mineral is completely wetted by the water phase, contact angle zero, there is no tendency for air bubbles to attach themselves to the mineral. The contact angle is a complex quantity because the
How to Determine Graphite in Drilling Mud
A field procedure for determining graphite in drilling mud is presented which is sensitive to 0.25 lbs/bbl and accurate to 20 per cent. The method, utilizing oil flotation principles, is suitable for use in all oil-free water base muds except those containing ligno-sulfonates, lignites, or surface active agents. Instructions for determining graphite in mud: Collect representative one gallon sample from
Soap Flotation
Table of ContentsExperimental MethodsSynthesis of Cassiterite and X Ray StudiesCassiterite FlotationFluorite FlotationEffect of BaCl2 and Other Activators on Soap Flotation of QuartzPreparation of MaterialsExperimental ProceduresBarium Activation of QuartzCalcium Activation of QuartzAluminum Activation Flotation test work on Bolivian tin ores some years ago led to the development of several workable schemes of selective soap flotation, but left unanswered many questions of
Volatility and Stability of Metallic Sulphides – Vapor Pressure
The direct reduction of metallic sulphides, as in the precipitation method for lead or antimony, is not a widely used process today. However, it might be employed for the production of a number of metals if the operation were carried out under reduced pressures. Two general procedures are possible; the reducing agent could form a stable non-volatile sulphide from which
Crushing Cavity Design
In these times of rising labor and material costs, it has become more and more necessary that attention be paid to some operating details which, in their obscurity, may be the key to major economies. Liner wear in crushing cavities of secondary and tertiary crushers can become an appreciable cost item when the material to be crushed is hard and
Steel Ingot Solidification
Table of ContentsRimmed SteelsProduction and Structure of Rimmed SteelsSegregation in Rimmed SteelCapped SteelsSemikilled SteelsKilled Steels Steel has been chosen as the metal whose solidification will be used to tie in the principles discussed in the previous papers. Although steel is the most important practical example that could be chosen, its solidification is complicated by the presence of many elements added
Laboratory Crushing Tests
Table of ContentsFracture of SolidsSize Distribution of Crushed MaterialEnergy Input Vs. New Surface Crushing has always been a major operation in the chemical and metallurgical industries, yet little is known about the theory of crushing, and today, the design of crushers is still based almost entirely on empirical knowledge and accumulated practical experience. In view of the increasing national need
Sinter Testing
This report to the American iron and steel industry marks the completion of a 1949 survey of blast-furnace sinter practice sponsored by the Sub-committee on Agglomeration of Fines of the American Iron & Steel Institute. The use of sinter in blast furnaces, sinter properties, raw materials, and sinter plant operation have been reported recently. Each 400-lb grab sample of sinter
Two-Way Belt Conveyor Transportation
Since 1920 use of belt conveyor transportation has increased steadily, and capacity in tons per hour per unit has increased at about the same ratio. Belt conveyor systems for simultaneous two-way material transportation have been widely discussed, but heretofore have proved impractical for specific operations. The two-way belt conveyor for coal mine service is not yet offered for sale as
Zone Melting
Table of ContentsNormal FreezingZone-Leveling ProcessesZone-Refining ProcessesDiscussion If a charge of binary solid-solution alloy is melted and then frozen slowly from one end, as for example in the Bridgman method of making single crystals, coring usually occurs, with a resulting end-to-end variation in concentration. Such coring, or normal segregation, is undesirable where uniformity is an object. On the other hand, for
Jet-Piercing
Table of ContentsPiercing TechniqueJet-Piercing BlowpipePiercing Results During 1950 the jet-piercing process was used commercially in the piercing of primary blast-holes in magnetic taconite at the preliminary taconite plant of the Erie Mining Co., Aurora, Minn. To produce the blasthole, jet-piercing utilizes thermal energy, as contrasted with the application of mechanical energy in churn drills and jackhammers. The heart of the
Magnetic and Chemical Analyses of Magnetite and llmenite
Table of ContentsDiamond-Drill Core AnalyserContinuous Magnetite Assay Investigation of the methods of analyses for magnetite and ilmenite in the Otanmaki iron-titanium ore and respective mill products has resulted in certain improvements in the methods conventionally employed. The outcome of the investigations is summarized as follows: Development of a diamond-drill core analyser for the determination of magnetic susceptibility of drill cores
Sponge Iron
Sponge iron as produced at Anaconda is a fine, —35 mesh, impure product, about 50 pct metallic iron, obtained from the reduction of iron calcine at a temperature of 1850°F by use of coke resulting from slack coal. The metallic iron particles are bulky and spongey and precipitate copper readily and rapidly from a copper sulphate solution. A good deal
Effects of Oxidation of Coal Flotation
The effects of oxidation on the flotation behavior of sulphide minerals have been extensively studied, but no similar study has been made of coals. Coals of bituminous and lower rank undergo atmospheric oxidation during mining and storage, and their degree of oxidizing increases with temperature and time of exposure. The problem of recovering fine oxidized coal from culm piles, rivers,