Blogs

Power Scale-Up for Agitating Slurries

An interesting problem with which the senior author has been concerned with is the scale-up of power requirements for slurry agitators operating in the laminar region with pseudo-plastic materials. Pulps of shaly ores, after various chemical reactions in aqueous leaching systems, are often difficult to settle and filter if agitation is violent. In these cases agitation must be at a

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Tertiary Zeolite Ore Mineral Distribution in Size Fractions

Zeolite ores and protores occur in extensive deposits in the western United States. A recent paper describes the general geology and mineralogy of these deposits and their geographical distribution. The zeolites are alkali- and silica-rich varieties of mordenite, erionite, chabazite, phillipsite, ferrierite, and clinoptilolite. The Tertiary zeolite ores consist of one or more zeolites (mordenite, erionite, chabazite, phillipsite, ferrierite, clinoptilolite)

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Use LIX-64 Extractant for Copper Pilot Plant Data

Table of ContentsDescription of The Liquid Ion Exchange ProcessChemistry of LIX-64Summary of Pilot Plant Operating Data Design parameters for scale-up to commercial plants are presented and discussed along with a revised capital cost estimate. The future pilot program is discussed, including minor design changes and the effect of entrained organic on dump leaching efficiency. Description of The Liquid Ion Exchange

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Designing a Mill for Maintenance

Table of ContentsMaintenance AreasEquipment AccessibilityMaintenance Aids Its purpose is to highlight the things that have been accomplished by the mill designers to lighten the load for the maintenance superintendent and to reduce the overall costs for the plant operator. The complexity of plant design, the civil and structural engineering problems encountered when the satisfactory maintenance layout is accomplished are appreciated,

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Heap Leaching Copper Ore

Table of ContentsDevelopmentMiningLeachingSolvent Extraction – Electrowinning Ranchers began its evaluation of the Bluebird Mine in late 1963. The property which included some 400 acres, adjoined one of the country’s leading producers – Inspiration Consolidated Copper Company. Such proximity led many to equate availability with undesirability. However, a relatively short period of exploration and metallurgical evaluation and a simultaneous assessment of

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Call For Contributors To Canadian Milling Practice 2020

It is with great excitement that we announce the forthcoming release of Canadian Milling Practice 2020. This much anticipated volume will follow the tradition established in 1957 with the release of “The Milling of Canadian Ores”, followed by “Milling Practice in Canada” in 1978, and “Canadian Milling Practice” in the year 2000. The new edition, supported by the Canadian Mineral

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Correlation Between Surface and Flotation in Silicates

Table of ContentsA Theoretical Model of Sorption RatesSorption and Sorption Rate in a Sulfonate SystemMaterialsSulfonatesMineralsProcedureResultsDiscussionSorption and Sorption Rate in an Amine SystemMaterialsAmineMineralProcedureResultsDiscussionIon-Exchange ExperimentsDiscussionFlotation of Silicate MineralsMaterials and ProcedureResultsOlivine GroupQuartz GroupSummary Experimental studies on the flotation of silicate minerals go back at least thirty or forty years (Bull, 1929; Bull, Ellefson, and Tylor, 1934; Fuerstenau, 1962; and Gaudin, Glover, Hansen, and

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Compression Testing of Green and Dry Iron Ore Pellets

Table of ContentsMaterials and EquipmentGreen Pellet TestingDry Pellet TestingEffect of Test Variables For many years the green and dry compressive strengths of pellets have been considered as possible criteria of pellet performance during induration. Although widely quoted throughout the industry, little attention has been given to standardizing the unfired pellet compressive strength test or to determining the characteristics of the

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Chemical Mining

Table of ContentsAdvantagesDisadvantagesChemical Mining TechnologyMining Economics and Ore EvaluationElements of the Leaching PhasePreparation of OresPractical Aspects of In Situ LeachingSolution Generation and RegenerationSolution Generation and RegenerationThe Recovery of Metals from Leach LiquorsRemarks Chemical mining is the in situ extraction of metals from ores located within the confines of a mine (broken or fractured ore, stope fill, caved material, ores in

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Sintering Hematite Iron Ore

Table of ContentsCharacteristic Data of Ores and AdditiveCharacteristic Data of the ExperimentsSinter OutputPhysical Quality and Structure The authors investigate the influence of the basicity index CaO/SiO2 on the sintering properties of hematite ore mixtures. The experimentation was performed with three different mixtures of ores from Tazadit, Nimba, Mano-River, Itabira, Marcona, Goa, Mapawa and Cassinga. Increasing the basicity index CaO/SiO2 between 0.1

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Filter Medium in Continuous Vacuum Filtration

Table of ContentsThe Fundamental Filtration EquationFilter Cloth ResistanceThe Mechanism of Flow The filter is an apparatus designed to hold the filter medium. At such a medium takes place the entire liquid-solid or gas-solid separation process. Hence, the medium is really the essence of filtration. Yet, the medium, an originally clean porous substance with trapped solids in it, is perhaps the

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Uranium Mill Waste Disposal

Table of ContentsDescription of Liquid WastesDescription of Solid WastesDisposal of Liquid WastesDisposal of Solid Wastes The presence of radioactivity in uranium mill wastes has resulted in somewhat unique waste disposal methods. In addition to the common problems of disposing of large quantities of solid wastes, neutralizing acids, minimizing dissolved heavy metals, and clarifying all liquid effluents, the uranium mill operator

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Underground Storage and Distribution of Hydraulic Fill

Table of ContentsPump PlantSand TankCement Many factors, some of which are not easily defined or described, must be considered in the design of a hydraulic backfill system. After participating in the design of several plants, I have a conviction that future refinements in sandfill systems must come in large part, from the merging of good design ideas and information from

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Depressants and Flocculants in Iron Ore Beneficiation – Starches and Starch Derivatives

Table of ContentsAnionic Silica FlotationCationic Silica FlotationMagnetite-Taconite ConcentrateFlocculation and Filtration This article discusses the effect of physical and chemical modifications of starches on the anionic and cationic flotation of silica from oxidized iron ores and magnetite-taconite concentrates, and the results of the interaction of starch, pH, and calcium ions on the flocculation, clarification, and filtration of iron ore slimes and

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How to Recover Silver from Waste Photographic Solutions

Table of ContentsPotential Recoverable SilverDescription of MaterialsLaboratory EvaluationsPrecipitation RateEffect of Barren Hypo on Metallic PrecipitantsEffect of Process VariablesEquipment and ProcedureSize of Steel WoolPacking DensityColumn SizeComparison of Different PrecipitantsIntermittent OperationSilver ConcentrationHypo AcidityThiosulfate ConcentrationEquipment Design and EvaluationSmall-Scale EquipmentLarge-Scale EquipmentSteel Wool Packed UnitWindow Screen Packed UnitEstimating When Unit is LoadedMarketing the SludgeSmelting the SludgeReduction SmeltingOxidation Smelting Metallic displacement-type silver recovery units are economical

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Secondary Breakage in Taconite Open Pit Mining

The mining of taconite, to provide feed for a processing plant, requires that the flow of material continue uninterrupted. This means first, that the crude must be of a size acceptable to the primary crusher in order to reduce the delays caused by plugging the crusher with chunks. Secondly, elimination of oversize in the pit will reduce costs of all

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Use of Rocket Jet Burners in Quarrying of Granite

Table of ContentsThe Thermal Spalling ProcessJet Channeling EquipmentRecent Process Developments The first step in the quarrying of granite, following removal of any overburden material, involves the freeing of large blocks from the formation. For many years the use of explosives was the accepted method of obtaining these blocks. Even today there are operations where this is considered to be the

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Priming and Boostering Anfo with Slurry Explosives

Following the wide-spread acceptance of ANFO as a useful, low cost blasting agent, studies have been made to adequately describe the physical and explosive properties of this material. As the quality of the AN blasting prill improved, reliability and sensitivity to initiation were greatly increased and many methods of priming were chosen from the standpoint of economics with little appreciation

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Flow of Solids in Bins

Table of ContentsTypical Storage and Flow ProblemsFlow PatternsDimension of Outlet There used to be a time when bins were designed for total volume and placed in any available place of the plant. Poke holes were provided and feed was maintained by manual prodding, lancing, hammering, and by various mechanical flow-promoting devices. Little thought was given to what occurred inside the

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How does Cyanide Depress Pyrite – Mechanisms

Table of ContentsExperimental Materials and TechniquesExperimental ResultsDiscussion of Results Oxidation potentials have been measured in the presence of various concentrations of cyanide, ferrocyanide, and ferricyanide and ethyl xanthate at various values of pH and related to flotation response. Eh-pH diagrams are constructed and show that the formation of surface ferric ferrocyanide is probably responsible for depression when cyanide is added.

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Laser Alignment Underground

Accurate and economic control of line and grade on long tunnels, large structures, excavations and waterways, has been a problem to surveyors and engineers for decades. The conventional method of surveying, incorporating a level, transit, and a number of surveying technicians, has proven, in the past, to be a very expensive and time-consuming operation. Operation of the laser is extremely

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Flotation Cell Hydrodynamics

Table of ContentsApparatus and Experimental DetailsLiquid SystemLiquid-Air SystemLiquid-Solid System A fully-instrumented driving mechanism has been constructed to study the power, aerating and solid suspension characteristics of several laboratory flotation machines. Machines operating over normal flotation speed ranges give constant power numbers in liquid systems indicating that they operate under fully baffled turbulent flow conditions. Owing to lack of geometrical scaling,

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Hydrochloric Acid Leaching of Iron from Aluminous Clays

Pennsylvania has ample reserves of high-alumina clays which are potential sources of alumina, but many of these clays contain large amounts of iron, which makes them unsuitable for treatment by acid processes. Of all the clay minerals tested, only gibbsite exhibits high acid solubility. Kaolinite, diaspore, and boehmite, which are the major alumina-bearing minerals in Pennsylvania clays, all display alumina

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Heap Leaching Economics

Expanded markets for copper in the past few years and a consequent search for new ore bodies have revitalized the widely known but seldom applied method of producing copper called heap leaching. This term should be differentiated from dump leaching in that the latter is applied to dumps of mixed oxide and sulfide ores (although either may predominate) that have

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