comminution handbook – contents handbook – contents chapter 1 comminution – an overview..... 1
TRANSCRIPT
Comminution Handbook – Contents
Chapter 1Comminution – An Overview ............................................................................................................................1
IntroductionContextBackgroundFundamentals of comminutionBreakage mechanismsClassification mechanismsComminution machines
Chapter 2Mineral Liberation ..............................................................................................................................................11
IntroductionWhy is liberation necessary?How does liberation happen?Measuring liberationModelling mineral liberation in comminution processesMineral liberation in separation processes
Chapter 3Particle Measurement Techniques ................................................................................................................25
IntroductionSamplingWet/dry sievingLaser diffraction particle size analysisSedimentation (sedigraph) and column settlingHydrocyclone methodsParticle countingSurface charge techniquesPhotomicroscopy-opticalElectron microscopyX-ray diffractionSurface area analysis
Chapter 4Ore Comminution Measurement Techniques ..........................................................................................43
IntroductionBreakage definitionsBond grindability testHardgrove grindability testZeisel testDrop Weight TestSMC Test®
SPI® testSAGDesign™ testCompression testBond Work Index values (Bond, 1953)Split Hopkinson pressure bar test
Chapter 5Tumbling Mills......................................................................................................................................................61
IntroductionBall mills for cementBall/tube mills for coalBall mills for oresAutogenous/semi-autogenous grinding millsRod millsRotary breakers for coalScrubbersGrinding ballsBuilding large tumbling mills
Chapter 6Compression Machines ....................................................................................................................................79
IntroductionPrimary crushersConventional cone crushersHigh-capacity crushing circuitsBed breakage crushersRolls crushersMineral sizersRoller millsHigh-pressure grinding rollsVertical roller millsHoromillsEnergy used in different circuits
Chapter 7High-speed Impact Mills ..................................................................................................................................99
IntroductionVertical shaft impact crushersHammer millsAtrita mills (combined hammer and attrition mills)Beater wheel mills
Chapter 8Stirred Mills ........................................................................................................................................................107
IntroductionComminution in stirred millsVertical stirred millsHorizontal stirred millsHosokawa Alpine fine-grinding mills
Chapter 9Mill Liners ............................................................................................................................................................125
The role of liners in tumbling millsVariations in liners for ore millsMaterials of constructionPotential issues with linersTypes of linersDesigning mill linersLiners for mill typesLiners in cement millsInspections, wear monitoring and ongoing optimisationCondition monitoring of linersRelining mills
Chapter 10Classifiers ............................................................................................................................................................145
Size separation in comminution processesClassificationTrommelsRake and spiral classifiersHydrocyclonesFine screensAir classifiers
Chapter 11Comminution Circuits for Ores, Cement and Coal ...............................................................................167
Comminution circuits for oresComminution circuits for cement clinkerComminution for coal preparation plantsControl of coal mills in power stationsControl of comminution circuits in coal preparation plantsControl of comminution circuits in cement plants
Chapter 12Milling Circuit Calculations ...........................................................................................................................191
IntroductionClassifier calculations – mass balancing and circulating loadPower calculations using Bond grindabilities
Chapter 13Modelling Comminution Circuits ...............................................................................................................215
IntroductionPerfect mixing ball mill modelEfficiency curve model for classifiersFitting example for ball mill – hydrocyclone circuitConclusions
Chapter 14Process Control .................................................................................................................................................227
IntroductionProcess measurementControl elementsTransmissionProcess control systems and devicesMeasurement and control costs – ‘rule of thumb’Grinding circuit controlResponse of the semi-autogenous grinding mill to change in feed rateControl of a crusherRole of the metallurgistProcess control techniques and skillsAdvanced process control systems
Chapter 15Case Studies of Control Systems ................................................................................................................245
IntroductionGrinding circuit control at the Phu Kham mine in LaosGrinding circuit control at Newmont’s Ahafo gold mine in Ghana
Chapter 16Circuit Design ....................................................................................................................................................265
Project definitionProcess development and circuit designSample selection and test workDesign criteriaFlow sheet optionsComminution energy calculationsEquipment sizing and selectionPlant layout
Glossary .....................................................................................................................................................................303
Index ...........................................................................................................................................................................309