Stripping overburden at Wheal Hughes copper mine …...Handbook on Quarrying Compiled by A.H. Dutton...
Transcript of Stripping overburden at Wheal Hughes copper mine …...Handbook on Quarrying Compiled by A.H. Dutton...
Handbook on Quarrying
Compiled by A.H. Dutton
HANDBOOK No. 1 (Revised edition 1993)
DEPARTMENT OF MINES AND ENERGY SOUTH AUSTRALIA
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Stripping overburden at Wheal Hughes copper mine opencut, Moonta. (Photo 039485)
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Contents
CHAPTER l INTRODUCTION................................................................................................................11 Production of construction materials in South Australia .........................................12 Crushed rock aggregates ............................................................................12 Construction sand .......................................................................................15 Brick clay ...................................................................................................15 Dimension stone .........................................................................................16 Production of minerals in South Australia ...............................................................17 Middleback Ranges iron ore deposits ........................................................17 LeighCreekcoalfield .................................................................................20
CHAPTER 2 PRODUCT TESTING AND SPECIFICATIONS .............................................................21 Sampling ..................................................................................................................21 Testing ....................................................................................................................21 Specifications ...........................................................................................................25 Fine concrete aggregate .............................................................................26 Coarse concrete aggregate .........................................................................26 Road sealing aggregate ..............................................................................27 Crushed rock and quarry rubble .................................................................28
CHAPTER 3 ENVIRONMENTAL MANAGEMENT ............................................................................29 What is the environment? ........................................................................................30 Why protect the environment? ................................................................................30 Range of environmental impacts .............................................................................31 Impactidentification ................................................................................................32 Visual impact .............................................................................................32 Noise ..........................................................................................................36 Dust ............................................................................................................36 Dereliction of land .....................................................................................36 Associated activities ...................................................................................37 Pollution .....................................................................................................37 Rehabilitation ..........................................................................................................38 When to start ..............................................................................................39 Where to start .............................................................................................39 What to plant ..............................................................................................39 After-uses ...................................................................................................39 CHAPTER 4 GEOLOGY ....................................................................................................................44 Rocks and minerals..................................................................................................44 Classificationofrocks .............................................................................................44 Lithologicalclassification ..........................................................................44 Classificationbyage ..................................................................................46 Rock structures Folds .......................................................................................................... 48 Faults ..........................................................................................................53
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Bedding ......................................................................................................54 Cleavage and schistosity ............................................................................54 Joints ..........................................................................................................55 Strike and dip ............................................................................................57 Weathering and Erosion ..........................................................................................58 Application of geology ............................................................................................58
CHAPTERS 5 DRILLS AND DRILLING ..................................................................................................60 Hammer drilling ......................................................................................................60 Surface hammers ........................................................................................60 Down-hole hammers ..................................................................................63 Machine mounting .....................................................................................69 Surface versus down-hole hammers ..........................................................71 Rotary drilling .........................................................................................................72 Auger drills ................................................................................................72 Reverse circulation drills ...........................................................................72 Rotary drills ...............................................................................................75 Circulatoryfluids .......................................................................................75 Operational features ...................................................................................76 Diamond drilling .....................................................................................................78 Choice of drill ..........................................................................................................79 Compressors ............................................................................................................80 Types of compressor ..................................................................................80 General requirements for air reticulation ...................................................82
CHAPTER 6 EXPLORATION ..................................................................................................................83 Stage1Officestudies ..............................................................................................83 Stage 2 Field reconnaissance and site selection ......................................................84 Stage 3 Preliminary site investigation .....................................................................85 Stage 4 Detailed site investigation ..........................................................................86 Stage 5 Preparing a development plan ....................................................................90
CHAPTER 7 EXPLOSIVES ....................................................................................................................91 Velocity of detonation (VOD) .................................................................................91 Types of explosives used in quarrying ....................................................................92 ‘Low’ explosives ........................................................................................92 ‘High’ explosives .......................................................................................92 Detonating (initiating) explosives ..............................................................93 Primers and boosters ..................................................................................93 Ammonium nitrate (AN) mixtures .............................................................93 Properties of explosives ...........................................................................................98 Sensitivity ..................................................................................................98 Relative weight strength ............................................................................98 Relative bulk strength ................................................................................99 Water resistance .........................................................................................99 Fumes .........................................................................................................99
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Detonating explosives ...........................................................................................100 Plain detonators (used with safety fuse) ..................................................100 Instantaneous electric detonators .............................................................100 Delay electric detonators ..........................................................................100 Signal tube detonators ..............................................................................103 Detonating cord ........................................................................................103 Initiation of explosive charges ...............................................................................105 NON-ELECTRIC INITIATION ..........................................................105 Safety fuse initiation ................................................................................105 Signal tube initiation ................................................................................106 Detonating cord initiation ........................................................................107 ELECTRICAL INITIATION ...............................................................109 Blasting circuit tester ...............................................................................111 Exploders .................................................................................................111 Firing from power mains .........................................................................113 Firing from batteries ................................................................................113 Electric circuits ........................................................................................113 Testing circuits .........................................................................................115 Hazardswithelectricfiring ......................................................................116 Explosives Regulations .........................................................................................118 Magazines ................................................................................................119 Transport ..................................................................................................121 Destruction of defective explosives.......................................................................119 Nitroglycerine compounds .......................................................................119 Watergel and emulsion explosives ...........................................................120 ANFO mixture .........................................................................................121 Detonating cord ........................................................................................121 Detonators ................................................................................................121
CHAPTERS 8 GROUND VIBRATION AND AIR OVERPRESSURE .................................................122 Ground vibration ...................................................................................................123 Vibration terminology ...........................................................................................123 Measuring ground vibration .....................................................................123 Damage ....................................................................................................125 Human response .......................................................................................126 Australian Standard ..................................................................................127 Controlling ground vibration ...................................................................129 Predicting ground vibration .....................................................................130 Air overpressure ....................................................................................................130 Measuring air overpressure ...................................................................................131 Damage ....................................................................................................131 Human response .......................................................................................133 Standards ..................................................................................................133 Proposed Australian Standard ..................................................................133 Controlling air overpressure ....................................................................133 Predicting air overpressure ......................................................................135 Service to industry .................................................................................................135
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CHAPTER 9 QUARRY BLASTING .......................................................................................................138 General considerations ..........................................................................................138 Purpose of blasting ...................................................................................138 Physical characteristics of rocks ..............................................................139 Amenity considerations ...........................................................................139 Primary blasting ....................................................................................................139 Blasting theory .........................................................................................139 Burden ......................................................................................................139 Spacing .....................................................................................................143 Fragmentation ..........................................................................................144 Selection of burden, spacing and hole diameter ......................................145 Trial blasts ................................................................................................146 Profilingblastholes..................................................................................148 Blasting in single holes ............................................................................149 Blasting in rows .......................................................................................149 Choice of explosive ..................................................................................150 Quantity ....................................................................................................150 Angle drilling ...........................................................................................153 Smooth blasting and pre-splitting ............................................................154 Tunnel (‘Coyote’) blasting .......................................................................155 ‘Bulling’ or ‘chambering’ holes ...............................................................156 Quarrying using small diameter holes .....................................................156 Quarrying using large diameter holes ......................................................156 Secondary breaking ...............................................................................................157 Popping ....................................................................................................157 Plastering (‘Mud-capping’ or ‘blistering’) ...............................................157 Drop ball ..................................................................................................158 Rock breakers ...........................................................................................158 Other methods ..........................................................................................160 Summary ...............................................................................................................160
CHAPTER l0 LOADING AND TRANSPORT........................................................................................168 Integrated loading and hauling systems ................................................................168 Dozers ......................................................................................................168 Scrapers (‘Bowl scrapers’ or ‘Wheeled scrapers’) ...................................169 Draglines ..................................................................................................170 Loading systems ....................................................................................................172 Rope shovels (‘Power shovels’ and ‘Face shovels’) .............................................172 Hydraulic excavator .................................................................................174 Front-end loaders .....................................................................................176 Bucketwheel excavators ...........................................................................177 Bucket chain excavators ..........................................................................178 Cranes ......................................................................................................180 Transport systems ..................................................................................................180 Trucks .......................................................................................................181 Belt conveyors .........................................................................................185 Ancillary equipment ..............................................................................................181 Graders .....................................................................................................181
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Water carts................................................................................................182 Lighting plants .........................................................................................182
CHAPTER 11 QUARRYING METHODS ...............................................................................................183 Stripping ................................................................................................................183 Ripping .....................................................................................................184 Moderate scale stripping ..........................................................................185 Large scale stripping ...............................................................................187 Quarries or open pits .............................................................................................188 Hillside .....................................................................................................188 Single bench .............................................................................................190 Multibench ...............................................................................................190 Strip mining .............................................................................................193 Dimension stone .......................................................................................198 Soft rock ...................................................................................................198 Sand and gravel ........................................................................................200 Salt ...........................................................................................................200
CHAPTER 12 QUARRY UNIT OPERATIONS ......................................................................................201 Sequence of quarrying operations .........................................................................201 Drilling .....................................................................................................201 Blasting ....................................................................................................203 Loading ....................................................................................................203 Transport ..................................................................................................205 Roads........................................................................................................205 Reclamation .............................................................................................206 Dumps and slime dams ..........................................................................................206 Dumps ......................................................................................................210 Slime dams ...............................................................................................208 Pumping and drainage ...........................................................................................211 Surface runoff ........................................................................................................211 Groundwater ............................................................................................211 Removal of inpit water .............................................................................212
CHAPTER 13 OPERATIONAL PLANNING ..........................................................................................213 General ..................................................................................................................213 Quarry layout and amenity ....................................................................................214 Rate of production .................................................................................................215 Stripping overburden .............................................................................................216 Quarry benches ......................................................................................................216 Pit slope .................................................................................................................217
CHAPTER 14 HANDLING PLANT ........................................................................................................ 222 Belt conveyors .......................................................................................................222 Width and speed of belts ..........................................................................225
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Lump size .................................................................................................225 Belt speed ................................................................................................226 Determining belt capacity ........................................................................226 Power ......................................................................................................227 Loading and unloading ............................................................................229 Cleaning conveyor belts ...........................................................................231 Specialbeltconfigurations .......................................................................232 Safety .......................................................................................................232 Bucket elevators ....................................................................................................233 Stockpiles and bins ................................................................................................233 Stockpiles ..............................................................................................................233 Bins ..........................................................................................................237 Pumps ..................................................................................................................237
CHAPTER 15 CRUSHING AND SCREENING ......................................................................................238 Definitionsincrushingpractice .............................................................................238 Crushing ................................................................................................................239 Classificationofcrushers .........................................................................239 Jaw crushers .............................................................................................240 Gyratory crushers .....................................................................................242 Cone crushers ...........................................................................................243 Single roll crushers ..................................................................................243 Twin and triple roll crushers ....................................................................244 Hammer mills ...........................................................................................244 Impactors ..................................................................................................247 Vertical shaft impactors ............................................................................247 Other crushers ..........................................................................................248 Selection of crushers..............................................................................................248 Planning factors .......................................................................................248 Reduction ratio .........................................................................................249 Primary crushers ......................................................................................250 Comparison of gyratory and jaw crushers ...............................................251 Secondary and reduction crushers ...........................................................252 Feeders ..................................................................................................................252 Screening ..................................................................................................253 Grizzlies ...................................................................................................254 Screens .....................................................................................................254 Selection of vibrating screens ..................................................................254 Installation and operation ......................................................................................261 Installation ................................................................................................261 Operating instructions ..............................................................................261 Operation and servicing ...........................................................................261 Matching the crusher to the quarry plant .................................................262 Dust control ..............................................................................................263 Washing ....................................................................................................263 Organisation of crushing and screening ................................................................263 Supply of quarry rock ..............................................................................263 Flow through the plant .............................................................................263 Removal of product ..................................................................................264 Examples of practice .............................................................................................264
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CHAPTER16 WORKSHOPS AND STORES .........................................................................................271 General considerations ..........................................................................................271 Preventive maintenance .........................................................................................272 Facilities ................................................................................................................273 Storage of dangerous substances ...........................................................................273
CHAPTER 17 OCCUPATIONAL HEALTH AND SAFETY .................................................................274 Safety ..................................................................................................................274 Accident recording ...................................................................................274 Legislative requirements ..........................................................................275 Induction of new employees ....................................................................275 Maintaining safety awareness ..................................................................276 Machinery ................................................................................................276 Fire extinguishers .....................................................................................277 Electrical ..................................................................................................278 General .....................................................................................................278 First aid ....................................................................................................279 Injuries not related to accidents ...............................................................279 Noise ..................................................................................................................281 Effects of noise.........................................................................................281 How to deal with noise ............................................................................282 Types of noise ..........................................................................................283 Reducing noise exposure .........................................................................283 Nuisance aspect of noise ..........................................................................284 Remedies ..................................................................................................285 Dust ..................................................................................................................285 Health hazards ..........................................................................................285 Dust measurement ....................................................................................288 Remedial measures ..................................................................................289
CHAPTER 18 ADMINISTRATION, MANAGEMENT AND FINANCE .............................................291 Company structure and procedures .......................................................................291 Quarry accountancy ...............................................................................................294 Quarry costs ...........................................................................................................294 Administration .......................................................................................................295 Labour ......................................................................................................295 Stores........................................................................................................296 Plant and equipment .................................................................................296 Management ..........................................................................................................296 Training .................................................................................................................297 Innovations ............................................................................................................297 Project evaluation ..................................................................................................298
CHAPTER 19 DEPARTMENT OF MINES AND ENERGY..................................................................299 Services available to the public .............................................................................299
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ACKNOWLEDGEMENTS ..............................................................................................302
SELECTED BIBLIOGRAPHY ........................................................................................302
GLOSSARY ..................................................................................................................304