Blogs
Monazite
Table of ContentsCharacteristics of MonaziteOccurrence of MonaziteUnited StatesUses Monazite formerly was described as moribund, but, in the light of recent developments, it is no longer so. It is the common source of the rare earths and thorium, both of which are becoming progressively important in industrial and other applications. Moreover, by the action of foreign governments, the sources on which
Mineral Fillers
Table of ContentsPropertiesMaterials Used as FillersMajor Fields of use for Mineral FillersBituminous CompositionsPaperPesticidesFertilizers Powdered nonmetallic minerals and rocks of many different types are used extensively in industry for incorporation in compositions and manufactured products The term “mineral filler” is commonly employed to designate a material that is used for a specific purpose but not as an essential or reactive component
Mining in Rhodesia
Table of ContentsOre TreatedPlant LayoutCoarse CrushingFine CrushingGrinding and ClassificationFlotationConcentrate Handling The Roan Antelope concentrator was originally designed with a nominal milling capacity of 6000 tons of copper ore per day but this was subsequently considerably exceeded. In broad outline the plant consisted of two No. 30 McCully gyratory crushers for coarse crushing, five 5½-ft Standard Symons crushers in open circuit
Grinding Energy Transfer by Impact
Table of ContentsExperimental ResultsEffect of Hammer Weight on StrainDiscussion of Results The transfer of kinetic energy of translation into other forms of energy by impact is a fundamental process in most crushing and grinding operations. During and after the impact process the original source energy may be accounted for in any of the following possible forms: Kinetic energy of translation
Lime – Quicklime & Limestone
Table of ContentsProperties Limestone-Origin and Mode of Occurrence Prospecting and ExplorationMining and Quarrying MethodsOperation of KilnsHandling the Product Lime is a very general term applied to products of limestone, in popular treatises often incorrectly, including ground or pulverized limestone used in agriculture. When used without qualifying adjective, the term usually means burned or calcined limestone, or quicklime, or calcia. Limestone is burned
Preparation of Lithium Metal by Vacuum
Table of ContentsPrevious WorkExperimental Equipment and ProcedureProduction of Lithium OxideReduction of Lithium OxideReduction with AluminumReduction of Lithium Chloride As this paper is written, the only method for the commercial production of lithium metal is by the fusion electrolysis of LiCl-KCl mixtures, as first proposed by Guntz. The details of the industrial process have not been made public but Osborg stated
Use Hydraulic Cyclones as Thickeners and Washers in Modern Coal Preparation
Table of ContentsMethod of Judging Performance of Coal WasherEfficiency or Recovery Curves of CyclonesExample of Cyclone ThickenersExample of Cyclone WasherIdeal Two-Dimensional Flow of Nonviscous FluidSummary For a number of years the cyclone, familiar to Americans as a dust collector, has been used as a thickener of suspensions at one of the coal-preparation plants of the Netherland State Mines in Limburg.
Recovery of Iron Ores Containing Titanium Manganese Chromium and Alkali Metal Sulfates
Most iron ores treated by the R-N direct reduction process yield metallic iron products considerably lower in titanium, manganese, and chromium oxides and alkaline metal sulfates/sulfides than were contained in the original ores. These metallic iron products are suitable as feed stock for the open hearth and electric steel-making furnaces. The elements which are rejected in part are acceptable in
Gravity Drainage Theory
Table of ContentsDifferential Equations of Capillary FlowTheoryCalculationsA Check on the TheoryDiscussion of Results This paper presents a theory for estimating the rate of gravity drainage of a liquid out of a sand column. Account is taken of the variation in permeability to the liquid as the saturation in the upper part of the sand becomes less than 100 pct. Differential
Sinking Large Diameter Mine Shafts by Rotary Drilling
A 6-ft diam core drilling machine has successfully completed seven mine shafts in Virginia and West Virginia to depths as great as 465 ft. There is no practical depth limitation to this new system—a potential method in formations not easily penetrated with other large-scale drilling programs—and higher penetration rates and larger diameters are possible in some formations already being drilled
Underground Conveyor
The Inland Steel Company operates five underground iron mines in the Lake Superior District. The two largest of these, from the standpoint of productive capacity, are the Sherwood Mine in Iron River and the Bristol Mine in Crystal Falls, both on the Menominee Range of Michigan. It is at these two mines that we have had our principal experience with
Single Stage VS Two Stage Grinding
Homestake crushing and grinding-practice was completely revised during the period of 1951-1953. During the conversion, both crushing, plants at the head frames, the Ross and the Yates, were rebuilt. The flowsheet changes at each plant involved replacing the two 8K gyratories with a single thirty inch gyratory for primary crushing to four inch. The gyratory discharges to a seven foot
Semi-Automatic Hoist
A Semi-Automatic hoist has been installed at the 2966 station of the Copper Queen mine, since neither the bulk of supplies handled nor the number of men engaged in developing the 3100 level justifies the constant attendance of two cagers and two hoist operators. The connecting service shaft between the 2966 and 3100 levels is actually a two-compartment raise. Below
Diatomite – Diatomaceous earth
Table of ContentsCompositionPropertiesOrigin and Mode of OccurrencePolitical and Commercial Control, Production and ConsumptionProspecting, Exploration and MiningTests and SpecificationsUses Diatomite is a hydrous or opaline form of silica, commonly known as diatomaceous earth, diatomaceous silica or kieselguhr. The term “infusorial earth” has lost its original meaning and today is incorrect in view of the distinctions between diatoms and infusoria. Various locality
Using Cyclone as a Thickener
Table of ContentsObject and Scope of InvestigationDescription of Equipment and Testing ProcedureForms of Cyclone Underflow ProductDesign FactorsOperation or Cyclone on Centrifugal-Drier EffluentOperation of Cyclone on Springbook SlurryCyclone Elimination of Contaminating Solids from Process WaterDescription of Experimental CycloneOperating ProcedureCyclone Application With the exception of pneumatic processes and a few special bencficiation methods of comparatively limited application, all mechanical coal-cleaning and mineral-dressing
Stone Crushing
Table of ContentsSources and ClassificationMineral Composition of RocksSoundness of RockStandard Sizes of Crushed StoneUses for Crushed StoneConcrete and Road MetalStone SandChemical IndustriesGlassStrippingQuarryingLoadingHaulageCrushingPrimary CrushingSecondary CrushingFine Crushing and PulverizingScreeningProduction of Stone Sand The use of stone as a building material in relatively large blocks is recorded in ancient historical records but only within the past 200 years has broken stone in small
Clay
Table of ContentsMinerals in ClayBase ExchangeProperties of ClayPlasticityTextureWater in ClayColorFusibilityOrigin of ClayDistribution of Clays and ShalesPolitical and Commercial Control, Production and ConsumptionProspectingMiningPlasticity, Fineness, and Water of PlasticityMarketing and Uses The term “clay” is applied usually to certain earthy rocks whose most prominent property is that of plasticity when wet. This permits them to be molded into almost any shape, which
Chromite
Table of ContentsPropertiesTypes of Geological OccurrenceDistribution of DepositsProspecting and ExplorationGrades and Specifications The minerals that collectively are known as chromite form an isomorphous series of the general formula (Mg,Fe)O. (Cr,Al,Fe)2O3. So wide is the range in chemical composition in this group that chrome ore consisting entirely of the mineral chromite may range from less than 30 pct to more than
Borax and Borates
Table of ContentsCompositionPropertiesDistribution of DepositsTheories of OriginProductionMining Methods and Preparation for MarketUses Borax a sodium borate and the principal sodium salt of boric acid, has been surrounded with romance and with a certain amount of mystery. Its early history is not entirely known but it has been contended that Marco Polo in his travels in the Orient introduced this material
Bleaching Clay
Table of ContentsCompositionPropertiesTheories of Behavior of Bleaching ClaysProspecting, Exploration and MiningPreparation for MarketFuller’s EarthActivated ClayTests and SpecificationsMarketing and Uses The term “bleaching clay” or “bleaching earth,” as used in the oil industries, refers to clays that in their natural state, or after chemical or physical activation, have the capacity for adsorbing coloring matter from oil. There are three common types
Shaped Explosive Charges
Table of ContentsMetallographic Survey of Cast-Iron SlugCollapse of Cavity LinerTheory of Jet Formation for Hemispheres Since the end of World War II interest has been increasing in the use of shaped charges in the mining industry and in other industries using explosives for blasting purposes. Shaped charges employ the principle known as the “Munroe effect,” which was discovered by Charles
Bauxite
Table of ContentsCompositionPropertiesMode of OccurrenceOriginDistribution of DepositsProduction and ConsumptionProspecting and ExplorationMining MethodsPreparation for Market Bauxite is known mainly as the ore from which aluminum is smelted but it has large use also in the manufacture of artificial abrasives and as a basis for certain chemical industries. A small amount is used for refractories and for other purposes. Composition Dana and
Low Carbon Steel Continuous Casting
Table of ContentsDescription of FacilitiesGeneral Sequence of Casting Plant OperationsCasting of Rimming SteelCasting of Killed SteelCasting of Semikilled SteelPlant Capacities Recognition of the benefits to be gained from the continuous casting of molten steel into finished or semifinished products has been given by scientific minds since the very beginnings of steel plant technology. In fact, Sir Henry Bessemer is credited
What is the Effect of Oxygen on Molybdenum
Specimens A, B, and C, of 0.040 in. diameter commercial molybdenum wire (Lot FW 13-40) were heat treated in the vacuum furnace. Internal friction studies of these specimens were carried out using a low frequency (approximately 1 cycle per second) torsional pendulum completely enclosed in a vacuum tank. The embrittling effect of small pressures of oxygen during heat treatment suggests