Blogs

Dry Grinding for Roasting

Table of ContentsDOUBLE ROTATOR BALL MILLDRY GRINDING SCHEMATICCENTRIFUGAL FANStatic ClassifierAIRSLIDEBucket ElevatorDYNAMIC CLASSIFIERSEPOL high efficiency separatorGrinding the discharge in side #2 of the grinding millFeeding the discharge back into the #1 side of the Mill. There are two parallel dry grinding circuits prior to roasting. Crushed ore is carried to the two circuits by the two reclaim conveyors located below the

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Bond Rod Mill Work Index Equipment & Apparatus Review

Table of ContentsIntroductionRocking of the laboratory millIssues with a smooth linerThe wave liner specificationThe meaning of inside diameterFinal thoughts and recommendationsReferences Commentary on the apparatus of the Bond rod mill Work Index by Alex Doll December, 2015 alex.doll@sagmilling.com The Bond “Third Theory” of comminution was originally divided into three size classes reflecting the varieties of comminution equipment common during the

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Preparing Cathode Wool for Smelting

Table of ContentsRemoving the WoolAcid Digestion of the WoolDrying the Cake The cathode wool is changed weekly or more often if necessary. Electrowin day is however the cut off point. First thing on Monday morning a sample should be taken from the cell for assay and then the eluate solution diverted to the spare cell. Removing the Wool Dump the solution

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Intensive Cyanidation

Table of ContentsDescription of the Intensive Cyanidation PlantThe Leach Vessel (See Fig. 16)The Filtration SystemThe Holding VesselOperation of the PlantCharging the Leach VesselOptimum Treatment TimeRinsing and Further LeachingDumping of Barren ConcentratePoints to RememberFurther Considerations The upgrading of gravity concentrate for smelting purposes by use of intensive cyanidation is still in the experimental stage. It involves the leaching out of the gold

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Preparing Of Gold Gravity Concentrates For Smelting

Table of ContentsAmalgamationAcid DigestionPoints to Watch The final concentrate taken off the Wilfley table is not suitable for direct smelting. The “lines of separation’ as shown in fig. 14 (Part 5) are not always clearly defined as there is some intrusion of impurities, namely steel, into the concentrate zone and likewise some gold finds its way into the middlings. It

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How to Operate a Wilfley Shaker Table

Table of ContentsHead MotionAdjustment of the Table’s DeckLongitudinal Level:Tilt of the deck:Water Wash:The action of the Wilfley TableOperation of the Wilfley Gold Shaker TableMaintenance of the Wilfley TableGravity circuit Starting Up/Shut-down ProcedureStart UpShut Down The Wilfley shaker table shown is a standard No.12 right-hand version. It is a mechanically operated reciprocating action table, consisting of a self-oiling enclosed type of

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Canada: A Golden Looser

Table of Contents196) and Last I think… CANADA at 77 Oz = 0.0024 ton = 1/415th of a tonShe has more gold than Canada 1) United States – 8,133 metric tons 2) Germany –3,381 metric tons 3) Italy –2,451 metric tons 4) France – 2,435 metric tons 5) China –1,693 metric tons 6) Russia – 1,317 metric tons 7) Switzerland

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Flotation Flowsheets

Table of ContentsConcentrate-middling routingA combination ratingPrimarySecondaryMiami Copper Co. millThe Inspiration Consolidated Copper Co. millMountain Copper Company, No. 1 concentratorConsolidated Arizona Smelting Co. millThe Anaconda Copper Mining CompanyDaly-Judge MillThe Burro Mountain ConcentratorTimber Butte Milling CompanyThe West Mill No. 2 of the Bunker Hill and Sullivan Mining CompanySummary Typical flotation flowsheets may be classified into two general types on the basis of the

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Froth Flotation and its Machines

Table of ContentsPulp-body-concentration ProcessesThe Potter and Delprat processesThe Froment processThe Elmore vacuum processAgitation-froth flotationThe Janney machine A Minerals Separation machineBubble-column Machines Pneumatic-type bubble-column machinesThe Callow cellThe Inspiration machineCentrifugal-type bubble-column machinesThe Ruth machineThe Groch machineThe Hebbard sub-aeration machineThe Cascade machineCombination Machines The Janney mechanical-air machineThe K and K machineComparison of Machines  Pulp-body-concentration Processes The Potter and Delprat processes Now combined and known by the

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Laboratory Scale Flotation Tests & Flotation Plant Results

Table of ContentsConcentrator Plant/Mill TestsEquipment and ProcessesSkin Flotation MachinesThe Wood machineThe Macquisten tubeThe DeBavay processOil-flotation Processes The Everson processThe Robson processThe Elmore processScammell and Wolf Process Translation of laboratory results into terms of plant/mill-scale operations is, in the usual case, less difficult in flotation than in gravity concentration, and in all cases more certain than where chemical reactions such as occur in

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Testing Flotation Oils and Frothers

Table of ContentsColorLimpid pointSpecific gravityViscosity and viscometerTar acid determinationSulphonationDistillation testRefractive indexOdorFluorescence The usual purpose of oil testing in flotation work is to determine that the oil in question is similar in physical properties and therefore probably in its behavior in the flotation cell to a given prior shipment, or in order to set specifications for flotation oil purchase. The following tests will give

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Flotation Process Development in Laboratory

Table of ContentsDifferential and preferential flotationSamplingPreparation of ores for testsNomogram for determination of pulp density Accessory TestsGrindingClassification & SettlingIn-House Pilot Plant Testing Differential and preferential flotation The pressing problems in differential and preferential flotation of ores are (1) the separation of lead sulphide from zinc sulphide, and (2) the separation of zinc and copper bearing sulphides from sulphides of iron. Methods seeking separation of

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Metallurgical Testwork for Process Development

Table of ContentsMineralogy & MicroscopyTABLE OF PRINCIPAL FLOTATION AGENTS CLASSIFIED ACCORDING TO THEIR CHARACTERISTIC TENDENCIES IN FLOTATIONAgents which tend to produce a voluminous froth:Agents which tend to enhance selection of sulphide minerals:Agents which tend to make stiff froths:Tests for a process for treatment of an oreThe procedure for preliminary testing, then, should be as follows:Flotation Testing of Oxidized Ores Mineralogy & Microscopy

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Flotation Equipment and their Test Procedures

Table of ContentsThe general rules follow:The variables affecting froth flotationThe variable results to be watched for and recorded A useful form for recording tests followsNotes on Descriptive TermsTexture: Character of Bubbles: Quality:Mineralization: Persistence: Testing axiomsProcedure in Flotation TestsGeneralMeasurement of quantities for testsAgitation froth machines without froth overflowSlide machineJanney laboratory machineMinerals Separation machinePneumatic machineVacuum machinePotter-Delprat process Practice in testing ores for flotation varies, of course, in

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Laboratory Flotation Equipment & Testing

Table of ContentsPreliminary Mineralogical ExaminationPreparation of the ore for flotationFlotation Testing MachinesGabbett mixerThe Slide MachineMinerals Separation Standard machineThe JanneyThe Elmore vacuum laboratory machineThe K and K laboratory flotation machineThe Ruth flotation testing machineThe HebbardThe Callow pneumatic laboratory flotation machineCascade laboratory flotation machineMotors and CurrentAlternating Current Direct Current Flotation tableFlotation AgentsPrincipal flotation agents or “oils.”Minor agentsOil TestingMiscellaneous Apparatus  The apparatus listed in the

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Froth Flotation Handbook

Table of ContentsMinerals that floatOres amenable to concentration by flotationMethods of flotationSkin-flotationOil-flotationFroth flotationPulp-body-concentration processesChemical-generation processesPressure-reduction processesBoiling processesAgitation-froth processBubble-column processDifferential flotationFlotation of oxidized oresFlotation agentsConditions of operation of froth-flotationTypical flow-sheets in flotation practiceStep treatmentFlotation results What is Flotation Flotation, as the term is applied to ore concentration, means the separation of one of the constituents of an ore from the remainder

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Explaining the Process of Froth Flotation

Table of ContentsFroth Flotation Theory ExplainedSurface Tension ExplainedAngle of Contact Explained:Explaining Adsorption:Understand ViscositySUMMARY:Application to Commercial Flotation Processes Film FlotationFroth FlotationMechanical-Agitation Froth ProcessPneumatic Froth ProcessPotter-Delprat Process: The flotation process for the concentration of ores is a method by means of which one or more of the minerals in the ore (usually the valuable ones) are picked up by means of a liquid film

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How Ores have Resistance to Crushing

During the last few years, one of the great problems in the milling of all ores has been that of crushing. This subject involves not merely the cost of the operation, but also the selection of the proper degree and character of crushing to yield the best metallurgical results on the given ore. Considering the diversity of machinery, one is

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Remove Arsenopyrite from Galena

Table of ContentsTechnique:Feed:Table Flotation Development:Skin Flotation:Agglomeration:Conditioning:Dilution:Capacity:APPLICATION:Broken Hill Concentrates:Test Work:Reagents:Lead Losses:Other Metals:Test Work ProcedureConditioning DeviceExtra Aeration:Wash Water and Slope of TableTechnique of TestsDetermination of the Most Suitable ReagentsEffect of Air JetsEffect of Varying Conditioning TimeResults of Final TestsConclusion: This paper deals with the application of table flotation to two unusual mineral dressing problems. Both problems involved the removal of interfering minerals

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A Glossary of Flotation

Absorb. To drink in, suck up, like a sponge. Adsorb. To condense and hold a gas on the surface of a solid, particularly metals. From L. ad, to, and sorbeo, suck in. Agitation is the act or state of being shaken, stirred, or moved with violence. From L. agitatus, agito, the frequent of ago, to drive. Baffle. That which defeats

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Gravity Spiral Concentrator Working Principle

Table of ContentsOptimum Operating Conditions of a Spiral ConcentratorThe Spiral’ Static DistributorThe Primary Spirals SeparatorThe Cleaner Spiral SeparatorMaintenance of the SpiralsHumphreys Spiral ConcentratorWhen to use a Gravity Spiral ConcentratorHumphreys Spiral Concentrator CapacitySpiral Concentrator The gravity spiral circuit is designed to extract and concentrate “coarse gold’ from the recirculating load in the mill grinding circuit and hence prevent a build-up within that circuit and the

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Effect of Impurities on Gold Slimes Refining Process

Table of ContentsEffect of SilicaEffect of Calcium CompoundsEffect of Magnesium CompoundsEffect of IronEffect of Nickel and CobaltEffect of AluminiumEffect of ZincEffect of ArsenicEffect of CopperEffect of LeadEffect of MercuryEffect of Bismuth and TinEffect of SeleniumEffect of TelluriumEffect of SilverWashing Out the Soluble SaltsTreatment of the Insoluble ResidueAmalgamation of Gold Slimes during the Refining ProcessEffect of Sulphate of LeadProportion of Coarse

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