Minerals, Metals and Sustainability Meeting Future Material Needs W.J. Rankin, CSIRO
Contents Preface Acknowledgements xv xvii 1 Introduction 1 2 Materials and the materials cycle 5 2.1 Natural resources 5 2.2 Materials, goods and services 6 2.3 The material groups 9 2.3.1 Biomass 9 2.3.2 Plastics 10 2.3.3 Metals and alloys 10 2.3.4 Silicates and other inorganic compounds 10 2.4 The materials cycle 12 2.5 The recyclability of materials 14 2.6 Quantifying the materials cycle 15 2.6.1 Materials and energy balances 16 2.6.2 Material flow analysis 16 2.7 References 23 2.8 Useful sources of information 24 3 An introduction to Earth 25 3.1 The crust 25 3.2 The hydrosphere and biosphere 26 3.2.1 Life on Earth 27 3.2.2 The Earth's biomes 28 3.2.3 Ecosystem services 30 3.3 Some implications of the basic laws of science 31 3.3.1 Thermal energy flows to the biosphere and hydrosphere 32 3.3.2 The greenhouse effect 32 3.3.3 The Sun as driver of both change and order 33 3.4 The biogeochemical cycles 34 3.4.1 The carbon and oxygen cycles 35 3.4.2 The water cycle 36 3.4.3 The nitrogen cycle 37 3.4.4 The phosphorus cycle 38
vi Minerals, Metals and Sustainability 3.4.5 The sulfur cycle 38 3.5 References 40 3.6 Useful sources of information 40 4 An introduction to sustainability 41 4.1 The environmental context 42 4.1.1 The state of the environment 42 4.1.2 The ecological footprint 43 4.1.3 The tragedy of the commons 46 4.2 A brief history of the idea of sustainability 47 4.2.1 The rising public awareness 47 4.2.2 International developments 47 4.2.3 Corporate developments 48 4.3 The concepts of sustainable development and sustainability 49 4.3.1 Alternative definitions of sustainability 49 4.3.2 Interpretations of sustainability 51 4.3.3 Responses to the challenge of sustainability 52 4.4 Sustainability frameworks 53 4.4.1 Triple bottom line 54 4.4.2 Eco-efficiency 54 4.4.3 The Natural Step 54 4.4.4 Natural Capitalism 55 4.4.5 Biomimicry 55 4.4.6 The five capitals model 55 4.4.7 Green chemistry and green engineering 56 4.4.8 Putting the frameworks into context 56 4.5 A model of sustainability 58 4.6 References 60 4.7 Useful sources of information 61 5 Mineral resources 63 5.1 Formation of the Earth 63 5.2 The geological time scale 65 5.3 Formation of the crust 66 5.3.1 Continental crust 67 5.3.2 Oceanic crust 68 5.3.3 The distribution of elements 68 5.4 Minerals and rocks 71 5.4.1 Mineral classes 72 5.4.2 Rock classes 75
Contents vii 5.4.3 The rock cycle 81 5.5 Mineral deposits 82 5.5.1 Formation of mineral deposits 83 5.5.2 Common forms of mineral deposits 84 5.5.3 The distribution of base and precious metal deposits 85 5.6 Resources and reserves 86 5.7 Extracting value from the crust 89 5.7.1 Physical separation 90 5.7.2 Chemical separation 92 5.7.3 The effect of breakage on the surface area of materials 93 5.7.4 By-products and co-products 94 5.7.5 The efficiency of extraction 94 5.8 References 94 5.9 Useful sources of information 95 6 The minerals industry 97 6.1 Mineral commodities 97 6.1.1 Traded commodities 97 6.1.2 Mineral commodity statistics 100 6.1.3 Reserves and resources of mineral commodities 101 6.2 How mineral commodities are traded 105 6.2.1 Mineral and metal markets 105 6.2.2 The complexities of trading mineral commodities 107 6.3 The economic value of mineral commodities 109 6.3.1 Hotelling's rule 109 6.3.2 Limitations of Hotelling's rule 110 6.4 The mining project cycle 112 6.4.1 Exploration 113 6.4.2 Evaluation and development 113 6.4.3 Design, construction and commissioning 114 6.4.4 Production 114 6.4.5 Project decline and closure, remediation and restoration 114 6.5 The nature of the minerals industry 115 6.5.1 Location 115 6.5.2 Hazardous nature 115 6.5.3 Size and structure 116 6.5.4 Minerals companies 117 6.5.5 Industry associations 120 6.5.6 Industry culture 120 6.5.7 Trends shaping the industry 121
j vim MmeraH, Metah and SusUtnabtHty 6.6 The economic and social impacts of mining 122 6.6.1 Mining as a route to development 122 6.6.2 The resources curse 123 6.6.3 Artisanal and small-scale mining 124 6.7 The minerals industry and sustainable development 124 6.7.1 Industry developments and formation of the ICMM 124 6.7.2 Sustainability reporting and sustainability indicators 125 6.7.3 Status of the industry 128 6.8 References 128 6.9 Useful sources of information 130 7 Producing ores and concentrates 131 7.1 Extracting rock from the crust 131 7.1.1 Surface mining 132 7.1.2 Underground mining 134 7.1.3 Solution mining 136 7.2 Beneficiating mined material 136 7.2.1 Size reduction 137 7.2.2 Separating particles 140 7.2.3 Separating solids from water 143 7.2.4 Agglomerating particles 146 7.3 Examples of mineral beneficiation flowsheets 147 7.3.1 Mineral sand concentrates 147 7.3.2 Production of iron ore fines and lump 147 7.3.3 Base metal sulfide concentrates 152 7.4 References 152 7.5 Useful sources of information 152 8 Producing metals and manufactured mineral products 153 8.1 Theoretical considerations 153 8.2 Metals 155 8.2.1 The principles of metal extraction 156 8.2.2 Metallurgical reactors 161 8.2.3 Smelting 161 8.2.4 Leaching 167 8.2.5 The stages in the extraction of a metal 170 8.2.6 The production of some important metals 174 8.3 Cement and concrete 183 8.4 Glass 185
Contents ix 8.5 Mineral fertilisers 186 8.6 Commodity ceramics 187 8.7 References 188 8.8 Useful sources of information 188 9 Energy consumption in primary production 189 9.1 Direct and indirect energy and gross energy requirement 189 9.2 Embodied energy 191 9.2.1 Calculation of embodied energy 192 9.2.2 Values of embodied energy 194 9.3 Embodied energy and global warming potential 196 9.3.1 Hydrometallurgy versus pyrometallurgy 197 9.3.2 Global greenhouse gas production 198 9.3.3 Impact of the source of electricity used 198 9.4 The effect of declining ore grade and liberation size on energy consumption 198 9.5 The lower limits of energy consumption 200 9.5.1 Energy required for moving materials 202 9.5.2 Energy required for sorting and separating material 202 9.5.3 Energy required for chemical processing 203 9.6 Energy sustainability indicators and reporting 205 9.7 References 210 10 The role of water in primary production 213 10.1 Global water resources 213 10.2 Water in the minerals industry 215 10.3 The embodied water content of metals 216 10.4 Water sustainability indicators and reporting 218 10.5 References 10.6 Useful sources of information 219 220 11 Wastes from primary production 223 11.1 Wastes and their origin 223 11.2 Solid wastes 225 11.2.1 Calculation of the quantities of solid wastes 225 11.2.2 Quantities produced 228 11.3 Liquid wastes 228 11.3.1 Wastewater 228 11.3.2 Acid and metalliferous drainage 229 11.4 Gaseous wastes 232
Mirwats, Mrt»!» <nnl 5ust»*n»Mity 11.4.1 The types of gases produced in smelting 232 11.4.2 The quantities of gas produced in smelting 232 11.5 The impact of wastes on humans and the environment 235 11.5.1 Examples of the impacts of mining wastes 236 11.5.2 Toxicity 238 11.5.3 Bioavailability 241 11.6 The international regulation of wastes 242 11.6.1 The Basel Convention 242 11.6.2 REACH and the European Chemicals Agency 243 11.6.3 Implications of the Basel Convention and REACH 243 11.7 References 244 11.8 Useful sources of information 245 12 Management of wastes from primary production 247 12.1 Management of solid wastes 247 12.1.1 Waste rock 248 12.1.2 Tailings 249 12.1.3 Residues from leaching operations and water treatment 253 12.1.4 Slags 254 12.2 Management of liquid wastes 255 12.2.1 Technologies for water treatment 255 12.2.2 Management of cyanide solutions 257 12.2.3 Management of AMD 258 12.3 Gaseous wastes 262 12.3.1 Gas cooling and heat recovery 262 12.3.2 Gas cleaning 263 12.3.3 Sulfur dioxide removal 266 12.4 Waste, effluent and emission sustainability indicators 267 12.5 References 268 12.6 Useful sources of information 269 13 Secondary materials and recycling 271 13.1 Options for end-of-life products 271 13.1.1 Recycling 271 13.1.2 Reuse 272 13.1.3 Remanufacturing 272 13.2 Drivers of recycling, reuse and remanufacturing 273 13.3 The benefits and limitations of recycling 273 13.4 Recycling terminology 274
Contents 13.5 Recovery, recycling and return rates for common materials 275 13.6 The energy required for recycling 275 13.6.1 The Gross Energy Requirement for recycling 278 13.6.2 The effect of repeated recycling 279 13.7 The effect of recycling on resource life 279 13.8 Recycling materials from simple products 281 13.8.1 Construction and demolition wastes 281 13.8.2 Glass 281 13.8.3 Metals 282 13.9 Recycling materials from complex products 284 13.9.1 Cars 284 13.9.2 Waste electrical and electronic equipment 287 13.10 Design for the Environment 291 13.11 References 292 13.12 Useful sources of information 294 The future availability of minerals and metals 295 14.1 The determinants of long-term supply 295 14.2 Potential sources of minerals 296 14.3 Crustal resources 297 14.3.1 The distribution of the elements in the crust 297 14.3.2 The mineralogical barrier 297 14.3.3 Hubbert's curve and the concept of peak minerals 299 14.3.4 Are many mineral deposits still to be discovered? 300 14.3.5 Crustal rocks as a source of scarce elements 304 14.4 Resources in seawater 305 14.5 Resources on the seabed 308 14.5.1 Deposits originating from land sources 308 14.5.2 Deposits originating from sources in ocean basins 310 14.5.3 Deposits originating from sources on continents and in ocean basins 310 14.5.4 Recovery and processing of deep ocean deposits 311 14.5.5 Legal aspects: the Convention of the Sea 312 14.6 Summary and conclusions 313 14.7 References 313 14.8 Useful sources of information 314 The future demand for minerals and metals 315 15.1 The determinants of long-term demand 315 15.2 Projections of the demand for mineral commodities 316
xii Minerals, Metals and Sustainability 15.3 Materials and technological substitution 318 15.3.1 Substitution limits and constraints 321 15.4 Dematerialisation 322 15.4.1 Intensity-of-use 322 15.4.2 Drivers of dematerialisation 325 15.4.3 Counters to dematerialisation 327 15.4.4 A case study 328 15.5 The IPAT equation 329 15.6 Summary and conclusions 330 15.7 References 330 15.8 Useful sources of information 331 16 Towards zero waste 333 16.1 The waste hierarchy 333 16.2 Reducing and eliminating wastes 335 16.3 Cleaner production 336 16.4 Wastes as raw materials 337 16.5 Waste reduction through process re-engineering 346 16.5.1 Examples of flowsheet simplification 346 16.5.2 Examples of novel equipment 348 16.5.3 Examples of novel processing conditions 350 16.6 Industrial ecology 352 16.7 Making it happen 359 16.8 References 363 16.9 Useful sources of information 365 17 Towards sustainability 367 17.1 Closing the materials cycle 367 17.1.1 The ICCM stewardship model 368 17.1.2 The Five Winds stewardship model 370 17.1.3 An integrated strategy for the minerals and metals sector 371 17.1.4 Drivers of stewardship 373 17.2 Market- and policy-based approaches to transitioning to sustainability 374 17.3 What does the future hold? 375 17.3.1 The'Great Transition'scenario 375 17.3.2 The World Business Council for Sustainable Development scenario 378 17.4 Summary and conclusions 379 17.5 References 380
Contents xiii Appendix I: A note on units and quantities 383 International System of Units 383 Scientific notation, significant figures and order of magnitude 383 Appendix II: A review of some important scientific concepts 387 11.1 The nature ofmatter 387 11.2 Conservation ofmatter 389 11.3 Energy, heat and the laws ofthermodynamics 389 11.4 Electromagnetic radiation 392 11.5 Heat transfer 393 Appendix III: GRI Sustainability Indicators 395 Appendix IV: Processing routes for extraction of common metals from their ores 401 Index 407 Elements arranged in alphabetical order 420 The Periodic Table 422