Blogs
Vibratory Conveyors
Table of ContentsClassification of Conveyor TypesMaterial Movement along Conveyor TroughTrough Amplitudes and Forces for Different Drive Mechanisms Vibratory or oscillating conveyors can be found in all types of industry, handling virtually any granular bulk material. They can be combined with other process functions, such as screening, cooling, drying and de-watering, while conveying. The conveyor can be covered and made dust-tight.
SAG Mill Variable Speed Drive
Table of ContentsVariable Speed DrivesDrive ReliabilityGrinding Circuit Capital Costs Large scale equipment can reduce both capital and operating costs for concentrators. Large semiautogenous mills can be effectively utilized in big mills but they must be kept fully loaded to take advantage of their great potential. With varying hardness ores, controlling throughput is difficult and careful design must take this into
Paper Making Pigments
Table of ContentsPaper CoatingTypes of Fillers Pigments are used in two segments of paper making, as the major component in paper coating formulations and, in small percentages, as fillers in the paper web. Historically, the dominant use has been in coating, however, recent developments have fostered a multifaceted effort to substantially increase the pigment component in the paper furnish. Factors
Thin Layer Wet Screening
Table of ContentsThin Layer Wet ScreeningThe Mechanics of Thin Layer Wet Screening Size reduction of ore in the refining process is necessary to liberate or expose the desired component of the raw ore. The geology of the ore deposit and the nature of the ore determine the extent to which the ore must be reduced to maximize the recovery economically.
How is Pyrite Pyrrhotite Floatabilitt Affected by Contact
Table of ContentsMaterials and MethodsResultsDiscussion Galvanic contact, occurring between electrically conducting minerals in flotation pulps, may affect the nature of mineral surfaces and influence their floatabilities. Rest potential and galvanic current measurements were made on an electrode combination of pyrite and pyrrhotite under nitrogen, air and oxygen aeration conditions, and the results were correlated with their oxygen-consuming characteristics and flotation
Role of Sodium Sulfide – Copper Lead & Zinc Ore Flotation
Table of ContentsChemistry of Sodium SulfideSulfidizationSodium Sulfide in Sulfide Minerals Flotation Sodium sulfide is one of the most widely used alkali metal sulfides in the flotation of copper, lead, and zinc minerals in their oxidized form. The sulfidization process, developed in the U.S.A. in 1915-20 for oxide copper minerals flotation, is especially suitable for oxidized lead ores in which the
Geochemical Modeling of in Situ Leaching
Table of ContentsISL Hydrology ModelThe Newton Raphson ProcedureAn Application of ISL and ISLGC Models An in situ leaching geochemical simulator consisting of flow, mass transport, and graphics support programs has been developed. Two dimensional flow in heterogeneous porous media is modeled using a semi-analytic boundary integral technique. This method involves mapping streamlines to straight line segments in the complex potential
Semi-Autogenous Grinding Cost Benefits
There has been a great deal of evaluation and discussion on the economics of semi-autogenous grinding versus conventional grinding circuits. The Henderson Mill, owned and operated by AMAX, Inc., is located 20 miles southeast of Parshall, Colorado. There are minor amounts of galena, chalocopyrite, sphalerite and about 3% pyrite. The major rock type is potassium feldspar-quartz with a Bond Work
Vibrating Screen Design Parameters
Table of ContentsModel DesignOperating and Control StrategiesResults An analysis of screen design options on the operating efficiency of secondary crushing plants has been conducted using a dynamic computer model. The model allows for the simulation of a wide variety of crushing circuits and can be run on either a microcomputer (IBM PC/XT) or a large time-sharing mainframe computer. Size reduction
Regeneration of Activated Carbon used for Recovery of Gold
Table of ContentsExperimentalThermal Gravimetric Analyses The process of treating granular activated carbon for return to service in the recovery of gold in Carbon in Pulp and Carbon in Leach circuits has been investigated. Carbons from four U.S.A. mines, one Canadian mine and one South African mine were characterized before and after regeneration. The use of thermal gravimetric analyses demonstrated the
Zero Order Production of Fines in Grinding
The phenomenon of zero order production of fines associated with the batch comminution of monosize feeds in tumbling mills has been examined in the context of the size discretized population balance model. It has been shown that the model admits zero order production kinetics only in an approximate sense. The necessary and sufficient conditions for approximate zero order production of
Portable Crushing
Decreasing ore grades and increasing labor and material costs have seriously eroded the economic vitality of many mining operations. Coupled with global economic stagnation and recession in the early 1980’s, these conditions have forced re-evaluation of operating strategies and methodologies with the objective of remaining competitive in a world marketplace. An important factor in system design and economics is utilization
Placer Sampling and Reserve Estimation
Table of ContentsPlacer SamplingSampling ProgramsSampling MethodsSpecial Problems Associated With Placer SamplingSample Processing or WashingSample WashingSample Washing EquipmentData ProcessingRecord KeepingReporting ValuesSplitting SamplesAssay ProceduresReserve Estimation And Placer ValuationCross Section MethodMethod of DiamondsConclusions Placer Sampling One of the most difficult tasks associated with placer mining is the sampling of the deposit. More placer projects have failed due to inaccurate assessment of the reserves
Spent Alumina Regeneration
Regeneration of the spent alumina was accomplished by using 0.25% NaOH and 0.5% NaOH. Figure 11 shows the release of selenium, silica, and aluminum when regenerating the adsorption columns that had received the mine leachate. In this case, the regeneration was performed in an upflow mode using 30% bed expansion. As expected, the losses of aluminum during regeneration increased with
Gold Prospecting in Quebec
Table of ContentsOutfitting for a Gold Prospecting Trip in QuebecTransportationRoutes to the Quebec Gold-BeltA Brief Synopsis of the Mining Laws of QuebecGeneral Geology of the Quebec Gold-AreaGold ProspectingScientific Prospecting MethodsField Tests for Determining the Approximate Value of Gold OresLocating a ClaimProspecting and Exploring a ClaimUnderground Exploration by Diamond-DrillingConclusion The prosperity of any nation depends, to a large extent, on its
Prospecting for Fine Gold
Table of ContentsDry-blowingPanning and other gravity methods of concentratingCentrifugal concentratingAmalgamatingSpectrographs analysisFire assayingChemical testingMethods InvestigatedDescription of Paper Chromatographic (P.C.) MethodOxidized samplesSamples carrying sulphidesField TrialsComparisons With Other Methods Methods used to determine the quantity of gold present in a sample vary according to the type of prospecting being done, and the manner in which the work is carried out. These methods can
Things to do to Improve Metallurgical Performance
Table of ContentsAlternative methods to restrict and eliminate the detrimental effect of critical size material on the performance of an autogenous mill.An Analysis of the Environmental Conditions in Palabora’s grinding circuit and the introduction of High Chrome Balls as Grinding Media. Alternative methods to restrict and eliminate the detrimental effect of critical size material on the performance of an autogenous
Magnetic Separators to Improve Mineral Cleaning
Table of ContentsFerrous Wheel Magnetic Separator Design and Operation PrinciplePERMROLL Magnetic Separator Design and Operation PrincipleTechnical FeaturesIndustrial Minerals Applications The strongest magnetic roll separator available on the market enhances certain industrial minerals purity to levels not reached previously. Exceptionally strong forces can also be utilized for processing relatively fine particles at feed rates several times greater than for prior art
Magnetic Separation of Fine Mineral Sulphides
The separation of fine sulfides becomes increasingly difficult at fine particle sizes. Potential fine size separation methods are froth flotation and magnetic separation. The mineral sulfides, with the exception of pyrrhotite, are either weakly paramagnetic (e.g. chalcopyrite) or diamagnetic (e.g. molybdenite). Those which are paramagnetic can only be separated using high-gradient magnetic separation (hgms) at high fields (up to 2
The 10 DEEPEST Diamond Mines in the World
The accumulation of diamonds has come a very long way since the first examples of this hugely precious stone were discovered in India in around 400 BC. Most of the world’s diamond deposits were formed over 1 billion years ago, yet gaining access to them has necessitated the development of hugely sophisticated modern technology. As mining engineering has become more
The 10 MOST VALUABLE Diamond Mines in the World (by Reserves)
Diamond mining is one of the most prestigious and profitable industries in the world. The ten largest diamond mines in the world by measurable reserves contain more than one billion carats of recoverable diamonds, and this naturally translates into many billions of dollars. It’s thus intriguing to look at how these carats are distributed. 10. Botuobinskaya – 69.3 million carats
Kaolin Tailings Ponds
Kaolin tailings ponds play an important role in reclamation of land and water. Discharges impounded from kaolin plants include oversize fractions consisting of coarse kaolin, mica, quartz as well as magnetically extracted contaminents, acid filtrates, and plant washdown streams. Tailing ponds perform an essential function in sedimentation of particulates, blending and reoxygenation of liquid waste, and neutralization and clarification of
Indirect Drying Filter Cake
The Thermal Disc is the only transport type dryer which can handle flotation, thickener underflow and pond recovery feed streams without the addition of a coarse fraction. The principle of operation differs from all other types of indirect dryers in that it is a volumetric displacement apparatus rather than first in first out. An operating level of mechanically fluidized coal
In Pit Crushing and Conveying Systems
Table of ContentsBelt Conveyors Widespread in Soft-Rock MiningTruck Haulage Versus Belt ConveyingIn-Pit Crushers; the Key to Hard-Rock ConveyingOperational Units Prove Concept Feasibility Belt conveyor systems, long the standard transportation technique in soft-rock open-pit applications, are encountering growing interest in the hard-rock open-pit sector as economic factors force companies to seek an alternative to costly truck haulage. A general review of