Fundamentals of Mineral Dressing PDF

Technical University of Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundamentals of Mineral Dressing Study program: Waste treatment and Recycling Lecturer: Assoc. Prof. Dusan Orac, PhD.  Minerals Processin...

Technical University of Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundamentals of Mineral Dressing Study program: Waste treatment and Recycling Lecturer: Assoc. Prof. Dusan Orac, PhD.  Minerals Processing gravity separation ore crushing, magnetic grinding concentrate sorting separation INPUT OUTPUT water chemical flotation decanting substance plant Martina Laubertová Základy úpravníctva 2  Lecture 1 Content: Meaning, goals and content of the course, conditions for completing the course. Basic terms in ore dressing. Raw material resources. Critical raw materials in EU. Iron ores. Overview, properties, composition and processing. 3 Fundamentals of Mineral Dressing Learning outcome (Goals of the course) After completing the Fundamentals of Mineral Dressing course, the student should be able to: explain the process of ore dressing, describe the principle of individual operations in ore dressing, know the difference between terms as nerast, mineral, ore, batch, yield, sieve analysis, etc., calculate the technological indicators of the mineral dressing such as: mass yield of concentrate and waste, yield of concentrate and waste, efficiency of the crushing, sorting and separation process, suggest a process of primary raw materials dressing, the output of which will be block scheme of dressing, in the assignment part of the semester project, practically test the basics of dressing of primary raw materials using the processes of crushing, grinding, sieve analysis, dewatering, flotation and magnetic separation. 4 Fundamentals of Mineral Dressing Conditions for completing the course: Mid-term evaluation (Credit): (30p) - credit examination (20 p) - semestral project (10p) Final evaluation (Exam):( 70p) - Total max.100p min. a 51p 5  Fundamentals of Mineral Dressing Outline of lectures 1 Meaning, goals and content of the course, conditions for completing the course. Basic terms in ore dressing. Material resources. Critical raw materials in EU. Iron ores. Overview, properties, composition and processing. 2 Heavy and light non-ferrous metala ores. Precious metal ores. Fire-resistance materials. Overview, properties, composition and processing. 3 General informations about ore dressing. Basic division of ore dressing processes. Technological indicators of ore dressing. 4 Diminution, principles of diminution. Crushing. Division and characterisation of shredder. 5 Grinding. Division and characterization of grinders. 6 Separation. Principles of recycling. Mechanical separation. Devices and types, characterization and usage. Sieve analysis. 7 Hydraulic separation. Devices, types, characterization and usage. 8 Separation. Principles of separation. 9 Separation in heavy liquids. Separation on jiggs. Devices, types, characterization and usage. Separation on water tables. 10 Magnetic and electric separation. Devices, types, characterization and usage. 11 Flotation. Theory and principes of flotation. Flotation additives. Devices, types, characterization and usage. Flotation schemes. 12 Auxiliary ore dressing processes. 13 Excursion. 6 Fundamentals of Mineral Dressing 7 Fundamentals of Mineral Dressing Basic terms Ore Mineral Composition (chemical, phase) Raw materials dressing Products of ore dressing processes – concentrate – waste – yield 8 Fundamentals of Mineral Dressing Raw materials Primary – ore, concentrate » specifics Secondary – half-product, waste » specifics 9  Primary raw materials/ Material resources: Mineral raw material is a solid, liquid or gas part of the earth´s crust (element, compound, mineral, rock) As mineral raw material are not considered: water except mineral water, peat, mud, sand, gravel, natural healing water... Mineral raw materials considered as useable parts of the earth´s crust, except water, is mineral which is able to be used in original state or after treatment in industry. A mineral deposit is a natural accumulation of minerals, as well as a base in a deep mine, an abandoned dump, a dump or a decanting plant, which were created by mining activity and contain minerals. - it can be mined profitably (currently or in the future). 10  Primary raw materials/ Material resources: Primary raw materials They form deposits of reserved minerals Natural rock structures and underground spaces, created by extraction of petrol, gas or salt, if they are suitable for storage of gases or liquids. Primary raw materials is owned by the country. A specific characteristic of mineral resources is their non- renewability and non-displaceability 11  Primary raw materials/ Material resources: Reserved and Unreserved Minerals deposits of reserved minerals - reserved deposits - represent the state's mineral wealth in its possession deposits of unreserved minerals (free) - (stone, gravel-sand, brick raw materials) - are part of the land 12  Primary raw materials/ Material resources: Reserves of reserved deposit – classification 2- According to suitability for economic use, they are classified as: Balance - reserves that can be used currently and meet the current technical, technological, and economic conditions for the use of reserved deposit or part of it. Off-balance - reserves currently unusable, but their usability is assumed in the future, taking into account the expected technical, technological and economic development. 13  Primary raw materials/ Material resources: According to the source (WORLD MINING DATA 2023), mineral resources are organized into five groups (Tab. 3): 1. Iron and ferro-alloy metals 2. Non-ferrous metals 3. Precious metals 4. Industrial minerals 5. Mineral fuels 14  Primary raw materials/ Material resources: Podľa zdroja (ročenka: NERASTNÉ SUROVINY SR 2021) nerastné suroviny možno rozdeliť na: Mineral resources: Energetical (coal, petrol, natural gas, uranium) Ore (Fe, Au, Cu, Pb, Zn, Sb, Hg, W, Mn, Ni, rare earth elements) Non-ore (barite, dolomite, magnetite, talc, basalt, zeolite, etc.) Building materials (building stone, gravel and sand, brick materials (loam, clay, slate)) 15  Primary raw materials/ Material resources: Mineral raw materials: metallurgy, electrotechnical, chemical, automotive, constructive, ceramic and glass industry, etc. Slovakia: Geological reserves of gold and silver ores in 6 deposits (approximately 59 mil. tons. Most of them are off-balance reserves. Geological reserves of mineral raw materials in 2020 on deposits of reserved minerals 17 184 mil. tons. Total mining in 2020 reached 26.5 million. tons. *Reserves of mineral raw materials are reported as geological reserves 16  Primary raw materials/ Material resources: Raw material – material input into the production Primary raw material is a natural material, which can be organic or inorganic Secondary raw materials are raw materials or materials recovered from waste, suitable for further economic or other use Ore is an aggregate of minerals, from which metal or more metals can be profitably recovered. Ore mineral is a direct material for metal production by metal extraction (for example galena, sphalerite a chalcopyrite). 17  Primary raw materials/ Material resources: Technical and economical conditioins allow to use raw material resources to the depths of 2-10 km below the surface. Classical methods of mineral raw materials mining are developed to the depths of 1,8-2 km below the surface (gold mining in RSA, uranium in Czech republic) Extraction of gaseous and liquid hydrocarbons and their deposits located at the depth of 7-10 km below the surface. Mining from the seabed (manganese concretions) is still in theoretical considerations of the possibility of their economic acquisition. Legal restrictions on the use of the ocean area are a serious problem. Mining of mineral raw materials on other planets 18  Non-traditinal resources of raw materials - Raw material resources in the universe are asteroids and the Moon Fig. Moon stone - basalt Fig. Illustration of mining at the asteroid (in the future) Composition: Al2O3, CaO, Fe2O3, MgO, TiO2 a Na2O, helium Mining problems: Moon dust, radiation, low temperatures... - Raw material resources in Antarctica, in the ocean... Martina Laubertová Základy úpravníctva 19 CRITICAL RAW MATERIALS IN EU 20 Fig. 3 Map of the critical raw materials in EU  CRITICAL RAW MATERIALS IN EU 34 critical raw materials 17 is considered as strategic raw material Out of the 34 critical raw materials identified, a specific strategic raw materials (SRMs*) list (17) has been created for the materials expected to grow exponentially in terms of supply, which have complex production requirements and thus face a higher risk of supply issues. https://www.consilium.europa.eu/en/infographics/critical-raw-materials/#0 21  CRITICAL RAW MATERIALS IN EU raw materials of great economic importance for the EU and with a high risk of supply disruption due to the concentration of their resources and the lack of good and affordable substitutes. Goals: - Increase and diversify supplies of critical raw materials to the EU, - strengthen circulation, including recycling, - to support research and innovation in the field of efficient use of resources and development of substitutes. - Strengthening self-sufficiency, with the aim of reducing dependence on third countries for access to critical raw materials, the EU has set the following goals for 2030: - MINING in EU: at least 10% of the EU's annual consumption should come from mining in the EU. - EU PROCESSING: at least 40% of the EU's annual consumption should come from EU processing. - RECYCLING in the EU: at least 25% of the EU's annual consumption should come from domestic recycling. - EXTERNAL SOURCES: no more than 65% of the annual consumption of each strategic raw material in the Union at any relevant stage of processing may come from a single third country. 22  CRITICAL RAW MATERIALS IN EU evidované geologické zásoby podľa BZVL SR Raw material Notes 1 antimony (Sb) 3 291 kt 9 deposits (app. 55 039 tons of metal Sb) 2 beryllium (Be) - Non-registered 3 fluorite - Non-registered 4 gallium (Ga) - Non-registered, in past production from imported bauxite 5 germanium (Ge) - Non-registred 6 graphite 294 kt 1 deposit 7 indium (In) - Non-registred 8 magnesium (Mg) - Non-registred 9 cobalt (Co) - In past, registered deposits, 17 000 kt of Ni-Co ore (app. 2 720 t of metal Co) 10 niobium (Nb) - Non-registred 11 PGM – platinum group metals - Non-registred (Pt, Pd, Ir, Rh, Ru, Os) 12 (Y, Sc a lanthanides) - In past, registered deposits, 8 kt (approximately 16 t of Rare earth elements metal Y+Sm) 13 tantalum (Ta) - Non-registred 23 14 tungsten (W) 2 846 kt 1 deposit (app. 6 546 t of metal W)  Primary raw materials Iron ore Ore of non-ferrous metals (NFM) – Ores of heavy NFM – Ores of light NFM – Ores of noble and precious metals Materials for refractory materials 24  Primary raw materials/ Metalal division: - Industrial division of metals in practical metallurgy a) Iron – iron alloys b)non-ferrous metals - Technical division of metals 1) Iron – iron alloys 2) Heavy non-ferrous metals a) with medium Mp (Cu, Ni, Co, Mn) 7,13-13,5 g.cm-3 b) with low Mp ( Pb, Sn, Zn, Cd, Hg, Sb, As, 3) Light non-ferrous metals (Al, Mg, Be, Li, Na, K, Ca, Sr, Ba, Ti) 4) Precious metals (Au, Ag, Pt) and platinum group metals (Ru, Rh, Pd, Os, Ir,) 5) Rare metals 25  Primary raw materials/ Metalal division: Rare metals: a) Light: francium, cesium, rubidium b) High-meltable: tantalum, tungsten, vanadium, niobium c) Disperse: gallium, indium, germanium, radium, selenium, tellurium d) Rare earth elements: lanthanides, scandium, yttrium e) Radioactive metals: uranium, radium, transuranic elements 26 Iron ores 27  1000 B.C. Fe2O3 + CO 28  Iron - properties Properties: colour: white-grey hardness: relatively soft reactivity: reactive - corrosion mechanical properties: malleability, ductility density: 7,86 gcm-3 melting point: ~ 1536 °C. use: in a pure state rarely, as an alloy steel the most widespread constructive material by rolling, forging, casting, pressing... 29 World supplies of iron ore for year 2019, in million tons 30 Top 10 centeres in iron ore mining, in 2014 31  http://www.mining.com/true-giants-of-mining-worlds-top-10-iron-ore-mines/ Mount Tom Price mine, part of Hamersley mine complex, Rio Tinto 32  http://www.ironore.ca/en/our-mining-process_293/ 33  Iron ores country mining country mining [million ton] [million ton] China 239 USA 57,5 Brazil 158,7 India 58,0 Russia Canada 36,8 Ukraine 133 RSA 32,3 Kazakhstan Sweden 20,0 Australia 128,5 Venezuela 17,3 34 VA ERZBERG GmbH, Austria – surface mine for iron ore extraction Martina Laubertová Základy úpravníctva 35 36  Iron ores – situation in Slovakia Slovakia: US Steel Košice – import from Krivoj Rog, UA – oxides Brazil 65%Fe Nižná Slaná – siderite Podbrezová – secondary raw materials 37  Iron ores Capacity in ores: 30 – 55 % Admixtures: Ti, Si, Ca, S, water Minerals: oxides, hydrated oxides, carbonates, sulfides, silicates, complex compounds 38 Technical minerals of iron Mineral Chemical formula Fe content [%] Hematite  Fe2O3 70 Maghemite γ Fe2O3 Goethite  FeO(OH) 62,9 Akagainite β FeO(OH) Lepidokrokite γ FeO(OH) Limonite Fe2O3. nH2O 59,8 Magnetite Fe3O4 72,3 - natural magnet Siderite FeCO3 48,3 Pyrite FeS2 46,6 Pyrhotin FeS 62,33 39  Questions from lecture 1 1. Define the difference between mineral, ore, concentrate and give an example for each. 2. What is the difference between bilančnými a nebilančnými zásobami surovín štátu? 3. Name what metals belongs into Critical raw materials group for EU. 4. Which country is in the first place of iron ore mining? 5. Name the most common technical minerals of iron. 6. From which country is the iron ore imported for iron production in Slovakia? 40 Thank you for your attention 41  Technical University of Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundametals of Mineral Dressing Study programme: Waste treatment and Recycling Lecturer: Assoc.Prof. Dušan Oráč, PhD.  Lecture 2 Content Ores of heavy and light non-ferrous metals. Precious metal ores. Refractory materials. Overview, properties, composition and processing. Does a metallurgical engineer need knowledge from Minerals for his work? Production of high quality products Economic success of the company The quality of materials depends on their chemical composition and physical structure. The chemical composition of the products depends on the chemical composition of the used starting materials - raw materials and all other materials that enter the production process, as well as on the course of the technological process itself. Does a metallurgical engineer need knowledge from Minerals for his work? Information about mineral resources is important: when processing mineral raw materials (properties of minerals), in the processing of mineral raw materials, i.e. input (chemical) and mineralogical (phase) analysis, during control of the production process, when buying and selling mineral raw materials - LME, in waste management.  Heavy non-ferrous metal ores 2) Heavy non-ferrous metals a) with medium Mp (Cu, Ni, Co, Mn) 7.13-13.5 g.cm-3 b) with low Mp (Pb, Sn, Zn, Cd, Hg, Sb, As) Copper ores  Copper - properties Properties: color: red hardness: soft reactivity: relatively inert mechanical properties: malleable, ductile, density: 8.94 g.cm-3 melting point: 1083 °C. Use: pure: electrical engineering (50%), engineering (20%), construction, alloys: brass (Cu-Zn), bronze (Cu-Ag) bell body hard bronze (78 %Cu + 22 %Sn) Electrical and thermal conductivity of metals Metal Relative electrical conductivity Relative thermal conductivity (copper 100%) (copper 100%) Silver 106 108 copper 100 100 Gold 72 76 aluminium 62 56 magnesium 39 41 zinc 29 29 nickel 25 15 iron 17 19 platinum 16 18 tin 15 17 lead 8 9 titanium 4 4  Metal price (copper price) 8260 USD/t Cu to 14.2.2024  Metal price (copper price) https://www.lme.com/en/Metals/Non-ferrous/LME-Copper#Price+graphs  Copper ores % - share of mining in the world in 2015. In 2014, 536,203 t of reserves in Slovakia Country Coutry Chile (27%) Slovakia Smolník USA (7%) Slovinky Canada Rožňava Australia (4,6%) Rudňany Zambia Hodruša- Hámre* Peru (12%) Poland Zlaté Hory China (9%) Congo (5%) Czech republic Jesenníky * Hodruša-Hámre district Žarnovica Banskobystrický region (Rozália mine) polymetallic ore, which also includes gold. Specifically, there is a deposit of Pb, Zn, Cu ores with Au and Ag content in the mine. Au content is approximately 6.5-7 grams per ton Čítajte viac: https://plus.sme.sk/c/22688246/slovenska-ruda-je-ako-milion-hraskov-sedem-z-nich-je-zlatych.html -  Copper ores Content in ores: ~ 1% (3%) Impurities: according to the type of ore – Ag, Au (undesirable As, Sb, S, Hg) Minerals: (300) sulfides, complex sulfides, oxides, sulfates, carbonates, silicates, complex compounds  Technical sulphide minerals of copper - they are of economic importance Mineral composition Mineral composition Mineral composition chalcozine Cu2S bornite Cu5FeS4 tetrahedrite Cu12Sb4S13 djurleite Cu1.97S idaite Cu5.5FeS6.6 tennantite Cu12As4S13 (nukundamite) digenite Cu9S5 fukuchilite Cu3FeS8 enargite Cu3AsS4 anilite Cu7S5 chalcopyrite CuFeS2 freibergite TE s Ag geerite Cu1.6S cubanite CuFe2S3 spionokopite Cu39S28 talnachite Cu9Fe8S16 yarrowite Cu9S8 mooihoekit Cu9Fe9S16 blue covelline Cu1+xS haycockit Cu4Fe5S8 covelline CuS Mineral Chemical Composition [%] formula Sulfide minerals Cu S Fe chalcopyrite Cu2S.Fe2S3 alebo 34,5 35 30,5 CuFeS2 Bornite 3Cu2S.Fe2S3 alebo 55,5 28,1 16,4 Cu3FeS3 covelline CuS 66,4 33,6 - chlacosin Cu2S 79,8 20,2 - Oxide minerals malachite CuCO3.Cu(OH)2 57,3 - - azurite 2CuCO3.Cu(OH)2 55,1 - - chryzokola CuSiO3.2H2O 37,9 - - cuprite Cu2O 88,8 - - tetrahedrite Cu12Sb4S13 Technical sulphide minerals of copper CHALCOPYRITE Technical copper oxide minerals mineral composition mineral composition cuprite Cu2O chrysocol CuSiO3.2H2O tenorite CuO chalcanthite CuSO4 malachite CuCO3.Cu(OH)2 Crocanthite CuSO4.3Cu(OH)2 azurite 2CuCO3.Cu(OH)2 atacamit CuCl2.3Cu(OH)2 Nickel ores  Nickel - properties Properties: color: shiny silver reactivity: inert density: 8.9 gcm-3 mechanical properties: high melting point, toughness melting point: 1425 °C. use: anti-corrosion, surface treatment, heat- resistant steels, electrical resistance,... Carcinogen  Nickel ores In the form country of country Russia-Kola sulfide Slovakia NH Sereď Canada Albanian Fe-Ni New Caledonia nepouite ore with Co (garnierite) content Jamaica Russia-Ural Greece oxide Cuba Philipines Albania  Nickel ores Content in ores: ~ 5% Impurities: Co, Fe, Cu, Au, Ag Minerals: sulphides, oxides, arsenides, laterites Monel is an alloy of nickel and copper (e.g. 70% nickel, 30% copper, traces of iron, manganese and silicon) that is not only heavy but can resist corrosion by seawater, making it ideal for connecting shafts in ships and desalination plants  Technical minerals of nickel mineral composition mineral composition pentlandite (Ni,Fe)9S8 chloantitis NiAs2 FeNi ore (Ni,Co)9S8 nickeline NiAs pentlandite (Ni,Fe)9S8 Ni(Fe,Co,Sb) millerite NiS nepouite (Al,Ni,Mg)2Si2O5(OH)4 bunzenite NiO Cobalt ores  Cobalt - properties Properties: color: shiny silver reactivity: inert density: 8.9 g.cm-3 melting point: 1490 °C applications: alloys, magnetization enhancement, anti-corrosion, heat-resistant steels, carbides, Co radiation bombs, steels, electrical resistance, pigments, enamels  Cobalt ores Country Country Zaire Slovakia NH Sereď Zambia Albanian Fe-Ni ore Russia with content Co Cuba New Caledonia Canada Morocco Finland Albania Co is not mined separately - a by-product in the production of Cu, Ni,...  Cobalt ores Content in ores: 0.06-0.7% Minerals: sulphides, arsenides, laterites, oxides  Technical cobalt minerals mineral composition binait (Co,Ni)3S4 carolit CuCo2S4 asbolane (Co,Mn).O.MnO2.4H2O.Fe2O3 Cobalite CoAsS skutterudite (Co,Ni)As3 cobaltomenite Co2O3.H2O Safflorite CoAs2 Safflorite (Ni,Co)As2 erythrite Co3(AsO4) 2.8H2O (Ag content up to 310 kg/t) garnierite (Al,Ni,Co,Mg)2Si2O5(OH)4 Lead ores  Lead - properties Properties: color: scratch silver shiny / matte gray reactivity: reactive, passivation on the surface density: 11.34 g/cmᶟ melting point: 327 °C mechanical properties: soft, malleable use: Pb accumulators, weaponry, alloys, protection against hard radiation, acid-resistant, pigments. highly toxic collector of precious metals  Lead ores Country t*1000 Europe t*1000 Australia 519 Sweden 112 USA 371 Ireland 54 Peru 217 the former 25 Yugoslavia Morocco 180 Canada 173 China ??? Pb rarely occurs alone - mostly Pb-Zn or Cu-Pb- Zn ores  Lead ores Content in ores: 0.5 – 15% (polymetallic ores) – Au,Ag,Cd,As,Sb,Sn,Bi,... Minerals: sulfides, carbonates, chlorides Impurity minerals: calcite, dolomite, pyrite, quartz  Technical lead minerals Mineral composition galenite PbS cerussite PbCO3 anglesite PbSO4 pyromorphite Pb5(PO4)3Cl Zinc ores  Zinc - properties Properties: color: bluish shiny reactivity: reactive, passivation on the surface density: 7 g/cmᶟ melting point: 420 °C mechanical properties: soft, malleable use: surface treatment, alloys - brass, chemical industry, pigments, wheel balancing,... toxic  Zinc ores Country t*1000 Europe t*1000 Canada 1009 Ireland 194 Australia 971 Sweden 158 China 755 Spain 151 Peru 674 USA 585 Czech Jesenník republic Mexico 369 Příbram Slovakia Hodruša- Hámre  Zinc ores Content in ores: < 10% Flotation concentrate: 60% Zn Minerals: sulphides, carbonates, silicates Impurity minerals: galena, pyrite, arsenopyrite, antimonite,... Tailings minerals: limestone, dolomite, corundum, quartz  Technical zinc minerals Mineral composition Sphalerite (dimorf: ZnS wurtzite) smithsonit ZnCO3 hydrozincite ZnO.H2O franklinite (ZnO,MnO)Fe2O3 hemimorphite 2ZnO.SiO2.H2O willemite Zn2SiO4 Manganese ores  Manganese - properties Properties: color: glossy, gray reactivity: constant at ambient temperature density: 7.43 g/cmᶟ melting point: 1245 °C mechanical properties: tough use: steel, deoxidation, armor, Haetfield, chemical industry, pigments, batteries, magnets,...  Manganese - properties More than 90% of extracted manganese is used in steel plants - for deoxidation of steel. Manganese steel is very strong and tough Heatfield steel: 13% Mn (high strength, abrasion resistance.  Manganese ores country country Russia Gabun RSA India Brazil Georgia China Kazakhstan Ghana Morrocco Czech Chvaletice republic Congo Slovakia Kišovec Švábovce impurities: Fe, Zn, Cu, Co, Ni, W, Ag,...  Manganese ores Mn ores are divided according to use: for the chemical industry - high content Mn for ferromanganese production for the production of mirror material for treating pig iron mostly shapeless amorphous  Technical manganese minerals Mineral composition burel - pyrolusite MnO2 rhodochrosite - dialogite MnCO3 psilomelane MnO2.H2O wad Mn2O3.H2O braunite 3 Mn2O3.MnSiO3 hausmanite Mn3O4 rhodonite MnO.SiO2 deep-sea concretions - nodules až 40 % Mn Antimony ores  Antimony - properties Properties: color: silver white density: 6.618 g/cmᶟ mechanical properties: hard, brittle melting point: 630.5 °C use: alloys, chemical industry, semiconductors (very pure Sb), solders, hard lead, weapons industry,.... toxic  Antimony ores country country China Slovakia Hodruša RSA Pezinok Kyrgyzstan Vajsková Bolivia Rudňany Mexico Rožňava Turkey Congo accompanying impurities: Ag, Pb, As, Fe, Cu, Hg,... Technical antimony minerals Mineral Composition antimonite – stibnite - Sb2S3 surma senarmonite Sb2O3 valentinite Sb2O3 cervantes Sb2O4 kermesite Sb2OS2 stibiconit Sb2O4.H2O tetrahedrite Cu12Sb4S13 Tin ores  Tin - properties Properties: color: silver white density: 7.298 g/cmᶟ mechanical properties: soft, malleable melting point: 231.9 °C below 13.2 °C tin plague (from a tetragonal space-centered structure to a cubic, diamond-like structure, Addition of 0.1% bismuth can completely suppress this undesirable transformation) use: alloys - bronze, food tins, tinfoil, solders, containers - history,  Tin ores Content in ores: up to 1% gravity enrichment Minerals: oxides, sulfides, together with tungsten - old waste dumps Impurities: As, Pb, Zn, Cu, Bi, Sb, W  Tin ores Country China Malaysia Indonesia Congo Peru Nigeria Bolivia Brazil Australia Portugal secondary raw materials Burma  Technical tin minerals Mineral composition tin - cassiterite SnO2 stanvein Cu2FeSnS4 Mercury ores  Mercury - properties Properties: color: silver density: 13.546 g/cmᶟ mechanical properties: liquid at normal temperature, high vapor tension melting point: - 38.8 °C use: amalgams, contacts, measuring technology, highly toxic  Mercury ores Pure mercury is very rare Content in ores: 0.15-0.5% flotation volatile roasting Minerals: sulphides Impurities: As, Sb, pyrite, quartz, limestone, organic matter  Hg ores country China Slovakia Rudňany Spain Kyrgyzstan Russia Ukraine Turkey USA Technical mercury minerals Mineral composition Pure mercury – very rare Hg cinnabarite - vermilion HgS tetrahedrite - schwazite 2Cu2S.Sb2S3.HgS Hg is sold in 34.5 kg bottles Light metal ores Al, Mg, Ti Aluminum ores  Aluminum - properties Properties: color: silver density: 2.699 g/cmᶟ mechanical properties: malleable, ductile melting point: 660.1 °C use: construction material casting alloys alloys for forming  Aluminum ores Bauxite (kaolinite, clays, nepheline...) Content in ores: 25-30% Bauxite: a mixture of minerals Additives: quantity  Bauxite Two groups of bauxites: tropical region – laterite weathering sedimentary bauxites – karst bauxites  Bauxite mining country x 103 t country x 103 t Australia 41.32 Suriname 3.156 Guinea 17.04 Venezuela 2.914 Jamaica 11.306 Greece 2.155 Brazil 9.356 Serbia China 6.5 Hungary Ajka, Halimba India 5.22 France Le Baux Russia 4.26 Romania  Mineral aluminum Mineral composition diaspore AlO(OH) boehmite AlO(OH) hydrargilit (gibbsit) Al(OH)3 kaolinite Al2Si2O5(OH)4 spinel Al2MgO4 chamosite Fe4Al(Si3AlO10)(OH6).nH2O thuringite 8FeO.4(Al,Fe)2O3.9H2O strygonite 4FeO.2Al2O3.4SiO2.4H2O  Admixtures in bauxite Fe minerals: hematite, goethite, limonite, siderite Si minerals:silica, opal, kaolinite Ti minerals: anatase, rutile, brookite other minerals : pyrite, dolomite, limestone other compounds : Ga, V, Zr, Ni, Be, Zn, P, Cr, C Types of bauxites Magnesium ores  Magnesium - properties Properties: color: silver density: 1,74 gcm-3 properties: reactive, strategic metal Melting point: 650 °C Use: construction material, refractory material, deoxidizer, magnesiothermy  Magnesium ores a large number of compounds silicates, carbonates, chlorides, sulfates sea ​water Admixtures: isomorphic admixtures of Fe, Mn, limestone, quartz, feldspar, clays Extraction of Mg raw materials Country Country Russia France Ukraine Spain Kazakhstan China Slovakia Košice Canada USA Germany  Magnesium ores Mineral composition magnesite MgCO3 dolomite CaMg(CO3)2 carnallite KMgCl3.6H2O brucite Mg(OH)2 forsterit Mg2SiO4 bischofite MgCl2.6H2O sea ​water dissolved chlorides, bromides, sulfates Titanium ores  Titanium - properties Properties: color: silver density: 4,5 gcm-3 properties: a highly reactive, strategic metal Melting point: 1725 °C Use: construction material, deoxidant, high chemical resistance, pigments oxides - special ceramics the strongest getter  Titanium ores Mineral composition anatase TiO2 brookite TiO2(rhombic) rutile TiO2 (tetragonal) ilmenite FeTiO3 perovskite CaTiO3 titanite CaO.TiO2.SiO2 Extraction of Ti raw materials Country Country Australia Canada Sierra Leone Sri Lanka RSA Brazil Norway Finland India USA Russia  Ores of the noble and precious metals Au, Ag  Gold- properties Properties: color: gold density: 19,3 gcm-3 properties: stable, malleable, ductile, strategic metal Melting point: 1063 °C Use: basis of currency, jewelry, electrical engineering, medicine  Occurrence of Au in nature Mineral Composition Pure Au Electrum Au,Ag teluridy AuxTey calaverite, sylvanite,kreunerit, nagyagite  Occurrence of Au in nature Gold-bearing minerals : – pyrite – Bornite – galenite – Silica – chalcopyrite – pure: gold, nuggets, – Sphalerite veins – Arsenopyrite – Tetrahedrite – pyrrhotite  Gold mining Country t Country t RSA 584 Bolivia 75 USA 331 Papua N.Guinea 61 Australia 256 Indonesia 55 Russia 249 Ghana 44 Canada 146 China 130 Slovakia B.Štiavnica Kremnica Zlatá Idka  Silver - properties Properties: color: silver density: 10,5 gcm-3 properties: still, malleable, ductility, the best electrical conductor Melting point: 965 °C Use: jewelry, electrical engineering, chemistry, photography industry,mirrors, alloys  Occurrence of Au in nature Silver-bearing minerals : – galenite – pyrite – alenite – chalcopyrite – sfalerite – Arsenopyrite – Tetrahedrite – pyrrhotite  Silver ores Mineral Composition Mineral composition Acanthite Ag2S miargyrite AgSbS2 pyrargyrite Ag3SbS3 matildite AgBiS2 proustite Ag3AsS3 stromeyerite CuAgS stephanit Ag5SbS4 freibergite* Cu12Sb4Sb13 polybazit (Ag,Cu)16Sb2S11 pure Ag *Ag content up to 30% in other sulfides (non-ferrous sulfides) – tenths of % Ag also forms tellurides minor representation of Ag - up to ¾ of the world's Ag mining  Silver mining Country Country in the past Mexico Czech Příbram republic Peru Kutná Hora USA Stříbro Australia Slovakia Banská Štiavnica Chile Canada Tungsten ores  Tungsen - properties Properties: color: silver density: 19,5 gcm-3 properties: very hard, stable, low coefficient of expansion, good conductor, Melting point: 3370 °C Use: carbides, light bulbs, electrodes, resistors, vacuum technology, dyes  Tungsten ores Mineral composition wolframite (Fe,Mn)WO4 scheelite CaWO4 ferberite FeWO4 hübnerite MnWO4 accompanying minerals: silica, fluorite, cassiterite, tourmaline,mica, sulphides  Tungsten mining Country Country China Czech Slavkov republic Barma Cínovec Malaysia Krupka Russia Bolivia Slovakia Jasenie – N.Tatry Peru USA South Kórea Portugal Spain  Tungsten ores W content in the ores : 0.5 – 2 % A potential resource of W: monazite coastal sands Total world production of W: ~ 45 000 t/year Molybdenum ores  Molybdenum - properties Properties: color: shiny silver density: 10,2 gcm-3 properties: acid resistant, Melting point: 2630 °C use: difficult-to-melt and special alloys, lighting technology, compounds such as pigments  Molybdenum ores Mineral composition molybdenite MoS2 molybdoscheelite 1 – 15 % Mo wulfenite PbMoO4 powelite CaMoO4 accompanying minerals: minerals Bi, W, pyrite, pyrrhotite,magnetite  Molybdenum ores Mo content in the ores: 0.2 – 0.5% World reserves of Mo: 2-3 million tons Total world production of Mo: ~ 120,000 t/year Molybdenum mining Country Cuntry Chile China Gibraltar Norway Mexico Japan Russia Greenland Kazakhstan Rhodesia Peru Refractory materials  Refractory materials Purpose: metallurgical and high-temperature aggregates heat resistance: stability above 1580 °C RM: highly stable oxides / graphite  Refractory materials Silica: temperature modifications: < 870 °C < 1470 °C < 1713 °C All changes are accompanied by structural changes = volume changes  Refractory materials Silica Dinas: > 93 % SiO2 – Raw material for production: quartzite, sand – Associated oxides of silica: Al₂O₃, TiO₂, MgO, K₂O, Na₂O  Refractory materials Aluminum oxide has 10 modifications - only three for RM Al2O3, b Al2O3, g Al2O3 RM: corundum - and Al2O3 fireclay - contains SiO₂ and Al₂O₃ (30-45%) Raw materials: clay, kaolin, sand,  Refractory materials Minerals for the production of corundum RM Mineral composition kaolinite Al2Si2O5(OH)4 halloysite Al2Si2O5(OH)4 montmorillonite Al2O3.4SiO2.H2O muscovite K2O.3Al2O3.6SiO2.2H2O  Refractory materials Magnesium oxide MgO – periclase Raw material: magnesite MgCO3 – dolomite CaMg(CO3)2 – Sea water Impurities : Fe – magnesioferrite  Refractory materials Dolomite products: by burning natural dolomites Ratio CaO : MgO = 1.39 as long as this ratio is considerably lower : magnesium dolomite Raw material: – dolomite CaMg(CO3)2 – impurities: limestone, silica, Al2O3, Fe2O3, Mn3O4  Refractory materials Another RM products forsterites Mg2SiO4 chromite with content Cr2O3 chrome-magnesite carbonaceous – graphite Košice: – magnesite, dolomite  Questions for the 2nd lecture 1. Which are the known copper ore mining areas in Slovakia? 2. Name the most famous sulphide minerals of copper. 3. Write a copper mineral with antimony content also found in Slovakia. 4. Define Bauxite and specify its two types. 5. What is the typical gold content of gold ore? 6. Kaolinite, halloysite and montmorillonite are minerals with the main useful metal.... 7. Which raw materials are fireclay and dinas?  Technical University in Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundametals of Mineral Dressing Study programme: Waste treatment and recycling Lecturer: Assoc.Prof. Dušan Oráč, PhD.  Lecture 3 Content: 1. General information on ore processing. 2. Definitions of the main terms in the mineral ore dressing 3. Basic division of mineral ore dressing methods 4. Technological indicators of adjustment.  Goals of the lecture 1. Define and differentiate the terms: ore, concentrate, monometallic ore, polymetallic ore, charge, yield, separation, etc. 2. Know how to divide the treatment of raw materials according to the type of treated material 3. Know the difference the principles of gravitational, magnetic, electric and flotation separation 4. Determine the conditions for choosing the separation method 5. Define the terms of the efficiency of the separation process, metallicity of ore concentrate and waste, concentrate enrichment, mass yield,  In general about the ores dressing (mineral processing/ore dressing) The aim of ores dressing is: To separate the useful minerals in the mined ore from the accompanying useless barren rock (a process called Separation) removal of unwanted impurities increasing the concentration of the beneficial component change in the physical/chemical properties of the treated material treatment is a mechanical, physical, biological, thermal or chemical process or a combination of processes carried out on minerals, including quarrying for the purpose of extracting minerals, changing their size and including their sorting, separation and leaching, as well as re-treatment of previously unused mining waste, except smelting, thermal production processes (other than limestone burning) and metallurgical processes according to Act no. 514/2008 Coll. Act on waste management from the mining industry Natural occurrence: impossibility of direct processing  In general about the ores dressing According to the type of material being modified, we know the following types of modifications: – ores dressing (ores Fe, Au, Cu, Pb, Zn, Sb, Hg, W, Mn, Ni, rare earth elements) – coal dressing (brown, anthracite..) – non-metals dressing (barite, dolomite, magnetite, talc, basalt, zeolite, etc. – waste treatment (industrial waste (slag, sludge), construction, municipal, WEEE, etc.)  In general about the ores dressing Division of ore dressing: – ferrous metal ores dressing (Fe, Mn) – heavy non-ferrous metals ores dressing (Cu, Pb, Zn, Sn, Sb, W, Mo,....) – noble metal ores dressing (Au, Ag, Pt) – rare metal ores dressing (W, Mo, Ti,...) – polymetallic ores dressing with the profit of more products – removal of harmful impurities from useful minerals  Division of ore dresisng processes Preparatory ore dresisng processes: – crushing – grinding – sorting Primary ore dresisng processes – minerals separation concentrate gangue Auxiliary ore dresisng processes – drainage 1-thickening, 2-filtration, 3- drying. – waste storage, sampling, process control and management.  In general about the ores dressing Basic terms: - Mineral - is an inorganic homogeneous natural substance, composed of one or more minerals, the composition of which can be expressed by a chemical formula or a chemical symbol. It is created by natural forces without human intervention, still in the ground - (minerals are not considered: synthetic diamond, glass, ceramics, building materials) Magnetite chalcopyrite malachite azurite smithsonite cinabarit Fe3O4 CuFeS2 2CuCO3.Cu(OH)2 CuCO3.Cu(OH)2 Zn2CO3 HgS  In general about the ores dressing Mineral raw material: is any natural mineral (mineral, rock) that can be used in some industry in its original state or preliminary treatment Non-ore raw material: mineral raw material containing a useful mineral from which no metal is obtained (asbestos, talc) Tailings (waste, tailings) - useless component of ore solid waste or sludge that remains after the treatment of minerals by separation processes, especially crushing, grinding, grading, flotation and other physico-chemical processes that separate valuable minerals from less valuable rock. Monometallic ore contains one utility mineral or metal Polymetallic ore contains several types of utility mineral (Cu ore approx. 1% Cu) In general about the ores dressing Ore: - is a heterogeneous inorganic natural substance. - is an extracted mineral resource that contains a technically separable and economically extractable content of utility metal - it is a mixture of free and overgrown pieces or grains of a utility mineral and barren rock, e.g. (Cu-ore – sulphidic from 0.5%, oxidic from 2%Cu) - Utility ore (is an inorganic homogeneous natural substance, the composition of which can be expressed by a chemical formula or a chemical symbol. it is created by natural forces without human intervention, still in the ground (it is not a mineral: synthetic diamond, glass, ceramics, building materials) - E.g.: Metal sulfides, sulfates, carbonates, silicates, oxides In general about the ores dressing Ore: - Their extraction depends on important factors and they are: - Ore richness: percentage content of utility mineral, mineral, metal in the ore. - The form in which the metal is present in the ore (pure, oxides, sulfides, etc.). - Content of accompanying elements. - Favorable (eg: noble metals in Cu and Pb ores, trace elements that increase the value of the ore. - Unfavorable (e.g.: As, P worsen and complicate the metallurgical processing of the ore and thereby worsen their value). In general about the ores dressing Ore 4. Physical condition of mined ore (chunk size, porosity, hardness). 5. Location and character of the deposit (surface mining, quarrying, underground mining, altitude of the deposit, distance from built roads). 6. Demand for the metal contained in the ore (the presence of radioactive elements, for example: U and Th can favorably affect the mining of other metals or vice versa). 7. Possibility of comprehensive use of all components of ores (polymetallic ores, tailings for other purposes, etc. In general about the ores dressing Ore 8. Strategic reasons (the need to import deficit metals, e.g.: (Cu, Ni, Co and Mo). 9. Deposit capacity (if the lifetime of the deposit is for a short time - mining and processing facilities are not advantageous to build. Obr. 1 surface mining Obr. 2 underground mining Division of ore dressing processes If the concentrate is slightly enriched after the first operation, it is called an intermediate product The waste is not yet completely depleted of the useful component - the enrichment operation is usually repeated (Dump, decanting plant - waste storage places) - Dump is an artificially constructed facility for depositing solid mining waste on the earth's surface. - Decanting plant is a natural or artificially built facility for the disposal of fine-grained mining waste, usually tailings mixed with various amounts of water from mineral processing and from the cleaning or recycling of water from operations Division of ore dressing processes - from the concentrates point of view it is a refining operation - in terms of waste, a control operation Charge is the input of the material into the finishing machine Yield is the obtained material (product) from the processing machine Dry or wet treatment (use of water) Crushing and grinding several successive stages of the so- called stages of the technological process  Process of ore dressing Gravitational separation Ore Crushing Magnetic Grinding concentrate and sorting separation INPUT OUTPUT Water Flotation Chemical substance Decanting plant Martina Laubertová Základy úpravníctva 16  Cominution (Crushing and grinding The extracted mineral raw material is a mixture of various overgrown pieces of utility material with tailings. In order to start separating the utility component and the waste component, they must be mechanically separated. It is broken down (comminuted) by crushing and grinding The method of crushing and grinding depends on the species and the way they grow together Crusher and mill equipment Sufficiently reduced material can be subjected to separation after re-sorting. https://www.youtube.com/watch?v=xwEn8s5sdco https://www.youtube.com/watch?v=lVBiRPkQ0MI Obr. 3 Jaw crusher Obr.4 Ball mill  Separation Separation is ore dressing process, in which the utility component and the waste component are separated on the basis of their physical and chemical differences: The methods are chosen according to the mineralogical composition of the individual components of the mineral raw material and according to their physical and chemical properties Optical separation Gravitational separation Flotation Magnetic separation methods Electric separation methods  Separation Separation methods Gravitational Flotation Magnetic Leaching separation separation Utility material Waste material https://www.youtube.com/watch?v=6kFONdchY0U https://www.youtube.com/watch?v=PMxjordJ73o  Separation Gravitational separation Principle: uses the difference in densities between the useful and inert components. wet method - in an aqueous environment static separation (in heavy liquids based on Archimedes‘ law) dynamic separation (in sets, on rafts) dry method – fluidized bed air stream - coal  Separation Flotation separation methods they use different physico-chemical properties of the surface of mineral grains, which can be purposefully influenced Principle: different surface properties of the utility and inert components (hydrophobicity - hydrophilicity) Naturally floatable minerals: sulphides, graphite Obr. 5 Flotation, flotation columns  Separation Magnetic separation methods Principle: diffrent magnetic cunductivity of the utility and inert components Relatively limited options Pre-treatment by roasting - the differences in the magnetic properties of the mineral components will increase, the separation effect will improve. Obr. 6 Magnetic separator  Separation Electrostatic separation methods Principle: different electrical conductivity, electrical charge (permeability) of the utility and inert components, when separating them from each other. Electrostatic separation Electrodynamic separation - waste  Gravitational separation ore Magnetic Crushing Grinding and sorting separation concentrate Water Flotation Chemical Decanting plant substance  Separation Conditions for basic methods: Characteristics of materials : – sulphides - flotation – magnetite, galenite - magnetic methods – magnesite - heavy liquids – The subtlety of intrusion : – finely ground ores: flotation – coarsely overgrown ores: mechanical methods Economical aspect Environmental aspect: laws impose norms what and how many emissions can get into the air degree of pollution of return waters noise caused by operation  Evaluation of the effectiveness of the separation process The basic principle of evaluating the division of a two- component system into individual components is used to evaluate the separation. The charge Q to the separation process is shown as a square. Optimal separation, in which the utility component K from the charge is completely separated from the non-utility companion rock T (waste). The more perfect the separation, the higher the separation efficiency.  Technological indicators The area of ​the rectangle on the left - the amount of ore. x-axis – metallicity (grade) () Axis y - mass yields () of products The amount of metal dispersed in the entire rock volume – () Entire area (Q) - amount of ore Blue area - the amount of metal dispersed in the volume of ore Metal yield to The amount of ore a concentrate - the actual After modification - two parts: its metallicity distribution achieved by concentrate of the beneficial the separation of the raw ingredient material waste Rectangle (K) - amount of concentrate Part (T) - amount of waste..  Evaluation of the effectiveness of the separation process Quantity of ore Q in kg - Grade of ore (i.e. metal content in ore) α in % Amount of concentrate K in kg – Grade of the concentrate (i.e. metal content in the concentrate) β in % Amount of waste T (or O) in kg – Grade of waste (i.e. metal content in waste) υ in %  Technological indicators The modification increased the metal content from () in the starting ore to () in the concentrate, and a certain amount of metal () goes to waste. The ratio of the metallicity of the concentrate and the metallicity of the ore = enrichment (Ob) Enrichment (Ob) is not a sufficient indicator: it may be a rich concentrate, but there is a small amount of it and much metal is lost in waste. Therefore, the mass yield of the concentrate denoted (c) is also taken into account  Technological indicators Mass yield of concentrate: the proportion of the amount of concentrate to the amount of starting ore K  c = 100 % Q Multiplying mass yield by enrichment: metal yield to concentrate  (%)  Technological indicators Practice: recoveries are calculated indirectly from balance equations:  c +  t = 100 % where  t =  c − 100 The sum of the amount of metal in the concentrate and waste is equal to the metal in the starting ore  c  +  t = 100. By solving the above equations for mass  − yield:  = 100 %  − c  Technological indicators In order to determine the mass yield, it is not necessary to weigh the starting ore and products - it is necessary to know their metallicity   − =. 100 %   − Comparing the works of two treatment plants - the yield of metal into the concentrate () is not a clear indicator - it does not express the purity of the concentrate. A new indicator is being introduced - the technical efficiency of separation  Technological indicators With an ideal 100% separation, a concentrate with the metallicity of a Galenite PbS 86,6 % Pb pure useful mineral is Sfalerite ZnS 67,0 % Zn obtained max Pyrite FeS2 46,6 % Fe Chalcopyrite CuFeS2 34,6 % Cu The value max is a constant quantity for each Chalcosine Cu2S 79,8 % Cu mineral and can be Antimonite Sb2S3 41,4 % Sb calculated from atomic mass numbers  Technological indicators Let N(kg) of pure useful mineral of metallicity max be in the investigated ore Q. Then it applies Q. = N. m ax  N = Q.  max The optimal mass yield will be : N Q.   opt = 100 = 100 = 100% Q  maxQ  max  Technological indicators The optimal yield depends on the metallicity of the utility mineral m Technical efficiency of separation is the ratio of what is actuall achieved success to the optimum achievable. It can only be considered a success extraction of the amount of metal whichshows the area behind the lineindicating metallicity (), because this the metallicity was already before the modification. Technical effectiveness of separation  Technological indicators Practically, metal is extracted by separation, the amount of which is represented by a rectangle with an area (-) * c The amount of whole metal in the ore that would be extracted under ideal conditions is shown by a rectangle of area (max-) * opt Technical effectiveness of separation r is: ( −  ) c r = ( max −  ) opt  Technological indicators By dividing both the numerator and the denominator by the value : r = ( −  )( −  )  max. 100% ( max −  )( −  )   Technological indicators An example. Separation of magnetite ore, where iron is bound in the form of Fe3O4 An ideal separation would be achieved if all magnetite with metallicity could be obtained max concentrate without residue into concentrate K and separate waste T with zero metallicity. The value max is calculated from the formula of magnetite Fe3O4 and and the atomic weights of iron (55.8) and oxygen (16). Fe3O4 max = 72,36 %. When processing magnesite, the goal is to obtain MgO from the ore, and therefore max is calculated as the MgO content in MgCO3 Technological indicators Auxiliary ore dresisng processes The separation products are very wet and are not yet suitable for further metallurgical processing, so they must be subjected to auxiliary operations. Auxiliary processes : - Drainage, filtration, drying, - Storage of waste in landfills and decanting plant, - dust removal, - sampling, - Process control and management - Briquetting and carbonization of coal, pelletization, agglomeration are among the main and sometimes separate processing procedures (refining procedures).  Questions for the 3rd lecture 1. What is the purpose of ore dressing? 2. Name the preparatory, basic and auxiliary ore dressing processes. 3. Define the term separation and list the basic separation processes. 4. List the conditions for choosing the separation method. 5. Define basic technological indicators of adjustment.  Vides crushing, flotation, magnetic separation https://www.youtube.com/watch?v=3np_Ipw3R-A https://www.youtube.com/watch?v=6kFONdchY0U https://www.youtube.com/watch?v=PMxjordJ73o https://www.youtube.com/watch?v=xwEn8s5sdco https://www.youtube.com/watch?v=lVBiRPkQ0MI  Technical University of Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundamentals of mineral dressing Study program: Waste treatment and Recycling Lecturer: Assoc. Prof. Dusan Orac, PhD  Lecture 4 Content: 1. Diminution, principes of diminution. 2. Crushing. Division and characterization of shredders.  Goals of the lecture 1. Define terms as comminution. 2. Describe the principes of comminution. 3. Know the difference between crushing and grinding. 4. Describe individual principes of crushers. 5. Know the difference between single toggle and double toggle jaw crusher. 6. Divide jaw crushers due to construction.  Comminution Introduction Mined ore is a mixture of different sized pieces (up to 1500 mm) The ore is crushed and ground to the required grain size The fineness of crushing and grinding depends on the character of the inclusion. It is ground to an optimal fineness – releasing the useful component of the ore – a finer grain size is never chosen – not economic – reducing the effectiveness of separation  Comminution The purpose of the comminution is: 1. Create products of such size as are necessary from the point of requirements for the final product of comminution, or as are necessary from the point of further finishing processes. 2. Open up the overgrown grains, i.e. release useful and waste components that have grown together. 3. Create products with a large surface area. 4. It requires overcoming binding forces on certain surfaces in the internal structure of these masses.  Comminution The process of comminution (crushing, grinding) is a complex process and depends on several factors: From the strength of the material, the shape of the grain, the size of the grain, homogeneity, density, etc., but also from the type of crushing equipment, whether the rocks are solid, layered, crystalline, from the degree of possible weathering, from the water content.  Comminution Of the properties of crushed ores and rocks, their strength in compression, shear and impact is of decisive importance. Less important is their strength in bending and compression. Other important properties: hardness, brittleness, plasticity and elasticity of the diminuted materials. An important factor is also the abrasiveness of the material and their resistance to rubbing and pounding. Among other properties of rocks, their structure and texture, their layering, fissibility, tectonic fissures and fissures arising during the release of rocks from the massif are important; degree of weathering. Rock moisture Brittle materials are crushed much easier than plastic ones  Comminution Crushing: the comminution of a solid object into parts, in which the forces of cohesion between the particles of the object are mechanically assisted and new surfaces are created Mined ore: particle size 0.1-1.5 m Mineral particle size: < 0.1mm Crushing and grinding: a series of operations to gradually reduce the size of the ore particles.  Comminution Division of the grinding process by grain size: coarse crushing – grain size is over 125 mm medium crushing – the grain size is over 25 mm fine crushing – the grain size is below 25 mm grinding – grain size is below 1.25 mm fine grinding – grain size is below 0.08 mm ultra-fine grinding – grain size is below 0.001 mm Intergrowth of different minerals a, b (coal and various sedimentary rocks) c (ores), d (cannot be separated from each other) e (leaching only), g (coarse crushing) h (fine crushing, grinding), i (two-stage) j (oxidic Mn, Fe or uranium), l (silicates, carbonates)  Comminution For each production procedure, it is necessary to choose the optimal size of the pieces or grains. Excessive crushing or grinding can cause problems: the wear (opotrebovanie) of crushers and mills increases and their function decreases, energy consumption increases, depreciation of some treated raw materials may occur, dustiness increases during the dry method and drainage is burdened during the wet method, they burden or even make some separational technological processes impossible.  Theory of comminution The theoretical comminution work is defined as the work consumed to overcome the internal intermolecular bonds while simultaneously increasing the surface of the diminuted mass and simultaneously increasing the surface energy. In the practical comminution process, a very significant amount of lost energy must be added to it, which must be expended during the practical comminution process. This loss cannot be measured, so it is impossible to express it precisely.  Theory of comminution Rittinger´s law –surface theory The energy required for reduction in particle size of a solid is directly proportional to the increase in surface area. E = KRfc(1/L2– 1/L1) Dstr. – the mean average of the feed dstr. – mean grain diameter after comminution C – constant  Theory of comminution Kick´s law – volumetric theory The amount of energy required to crush a given quantity of material to a specified fraction of its original size is the same, regardless of the original size. E = KKfc loge(L1/L2) Bond´s law – the trird theory of diminution The work required to form particles from very large feed is proportional to the square root of the surface-to-volume ratio. E = KBfc [(1/L2)1/2- (1/L1)1/2]  Crushing Čečot: „ Do not crush anything unnecessarily!“ To comply with the principle of avoiding unnecessary crushing, sorters with openings of the same size as the bottom opening of the crusher are placed in front of the crushing devices.  Crushing Crushing circuit – open 1- mineral raw material 2- seeder 3- overflow d – diameter of the largest pieces after crushing 5 – crusher 6- crushed pieces D – diameter of the largest pieces before crushing Mineral raw material 1 Is fed to siever 2 Pieces smaller than d fall through siever 3 and pieces 4 larger than d are transferred to a crusher where they are crushed to a size smaller than d. Crushed pieces 6 are combined with sub-sieve material 3. Unnecessary pre-crushing is eliminated, the consumption of driving energy and wear of the crusher component is reduced, and less dust is generated.  Crushing Stage of crushing: i – stage of crushing D - the diameter of the D i= largest pieces of ore before crushing d d – diameter of the largest pieces after crushing Each crushing device has a certain range of satge of crushing. Product of crushing stages of individual devices = total crushing degree ic ic = i1. i2.i3. i4....... in For example: pieces of ore with a diameter of 600 mm need to be crushed to a final size of 5 mm. The ore must shrink 600:5=120 times. Degree of crushing i=120 ic = 60 x 20 =120  Crushing According to the size of the crushed pieces, crushing is divided into: D(mm) d(mm) Way of treatment coarse 1000 – 500 200 – 100 dry medium 200 – 100 100 – 20 dry fine 100 – 20 20 – 3 dry grinding 15 – 0,5 do 0,007 wet 0,5 do 0,1m wet  Crushing Large investment and operating costs: 45% of total costs – crushing and grinding 60-70% of the total costs - investment costs 50% of total costs - electricity costs Energy requirements: kWh/t rudy coarse crushing 0,2 – 0,5 medium crushing 0,5 – 2 fine crushing 1,0 –10 grinding 100  Principes of crushing According to the method of mechanical action of forces: the direction of the crushing force a) crushing b) spreading c) splitting d) pounding e) cutting  Principes of crushing In practice: - combination For coarse and medium crushing, crushing is the most economical and spreading is less economical due to high energy consumption and large losses. When choosing a crushing method, the physical-mechanical properties and grain size of the material play a decisive role.  Principes of crushing The division of rocks into groups according to strength with the indication of some values ​of the limit of compressive strength Rocks Compressive strength limit [MPa] Solid objects More than 50 Medium solid objects 10 to 50 Fragile objects Less than 10 granite 120-140 Quartzite 200-220 Sandstone 50-100 Limestone 40-180 Limonite 42-125 Magnetite 77-105 Anthracite 25-30 Black coal 7-24 Clay slate 60-160 Clay with 3-9% 2-6 moisture  Principes of crushing Different stages of material crushing Especcially hard to basalt, corundum, carborundum crush Very hard to crush diabase, granite, quartz, quartzite, pyrite, hematite, magnetite, sandstone Hard to crush siderite, feldspar, calcite, magnetite, sandstone, siderite, marble, copper, lead, manganese, chromium ores Medium crushable bauxite, pumice, dolomite, feldspar, fluorite, calcite, magnesite, barite, slate Easy to crush limonite, gypsum, mica, graphite, rock salt, potassium salts, talc, black and hard brown coal Very easy to crush brown coal, kaolin, chalk, clay  Principes of crushing When choosing different types of crushers and mills, the following determines: Mechanical and physical properties of divided minerals and rocks, The size of the pieces or grains to be crushed or ground, The size of the pieces and grains to be obtain, The required activity of the machine in m3/h or in t/h, Amount of fine grains or particles of smaller diameter than the desired size of the product to be obtained.  Principes of crushing Principles applied in the selection of crushing equipment: The width of the entrance hole should be 10-20% larger than the diameter of the largest piece in the batch. 15-20% power reserve in case of accidental overload Specific energy consumption as low as possible Minimal dust production (harms both staff and machine) Machine design - easy replacement of parts that are subject to wear Crushing products of even grain size Easy change of grinding level Crusher fuses against damage to the main parts - if hard objects get into the crusher, etc.  Divices for crushing In practice: Combination of individual principes A large amount of different types of crushers – Jaw crusher: - the material is crushed by the movement of the jaws (coarse and medium crushing) – Cone crusher: - pieces of ore with an eccentrically moving crushing cone – Roll crusher: - counter-rotating cylinders crush the ore by crushing (medium crushing) – Hammer crusher: - impact crushers and disintegrators that act on pieces of ore by hitting the rotating parts of the crushers (medium and fine crushing) Jaw crusher  Jaw crusher Jaw crusher coarse crushing, or medium crushing usually used in the first stage of crushing relatively simple construction the ability to hold large pieces of crushed ore considerable performance easy interchangeability of spare parts easy operation and maintenance  Jaw crusher Jaw crushers Basic types: with upper attachment of the movable jaw with the lower attachment of the movable jaw according to construction : – double-toggle capture angle – single-toggle  - angle between perfomance depends on: jaws (15-35o) depends on the – ore character coefficient of friction – crushing stage between the crushed – size of feeding hole material and the jaws – capture angle – other factors  Jaw crusher Principes: The upper opening of the crusher – MOUTH The lower opening of the crusher – SLOT The basic size of the mouth and slot are width and wheelbase. The wheelbase of the exit slot is regulated by adjusting the fixed jaw using the regulating device (12). The safety plate (13) forms a simple and effective protection against failure (foreign/stranger object). Energy consumption (0.27-0.54 kWh.t-1). Advantages of jaw crusher: with upper fixing of the movable jaw. Simple construction, easy replacement of spare parts, repair, service. Disadvantages: restless operation with frequent impacts, with uneven dosage, the crusher clogs. Jaw crusher  Jaw crusher Single-toggle and double-toggle jaw crusher https://www.911metallurgist.com/blog/difference-between-single-double-toggle-jaw-crusher  Jaw crusher Principes The raw material is crushed in the space between a fixed and a movable jaw, which performs a rocking movement with the help of a connecting rod around a horizontal axis and two toggle plates. The connecting rod is freely suspended on an eccentric shaft with two flywheels. The backward movement of the movable jaw is made possible by a spring rod. By opening the jaw, the material is pushed into the mouth of the crusher by its own weight, and when it is clamped, the material is crushed. The crushing chamber has a curved shape, replaceable grooved jaw plates made of manganese or chrome steel. Double toggle jaw crusher Jaw crusher – single toggle Jaw crusher Single toggle jaw crusher  Single toggle jaw crusher Against the frontal fixed jaw, a swinging jaw moves with a complex movement, the upper part of which is rotatable directly on the eccentric shaft. The jaw copies the path of an obliquely inclined ellipse. At the bottom, the jaw rests on a swinging strut plate. The oscillating and spring plate form the moving mechanism of the jaw. Flywheels are dimensioned at both ends of the shaft, one of which is also a wedge pulley. The flywheels are connected to the shaft by a special safety device. The material is crushed by the pressure created by alternating clamping of the crushing jaws. spring and tie rod, hydraulic adjustment device, side armor plates. Jaw crusher Jaw crusher Jaw crusher Jaw crusher  Jaw crusher The material enters the crusher hopper (1) from trucks or using loaders. Before entering the jaw crusher, it passes through a sieve (2). Smaller pieces of rock fall through (3). The remaining oversized material passes through a jaw crusher (4) sized to less than 200 mm. Electromagnet (5) removes steel from old mines. The material is transported by (6) conveyor to the destination station.. Jaw crusher with feeder  Cone crusher According to construction – Cone crusher for coarse crushing – Cone crusher with fixed shaft – Cone crusher for medium and fine crushing - Symons  Cone crusher The parts of the crusher are made of cast steel, lined with manganese steel, the degradation is low. The lining is replaceable  Cone crusher According to the purpose and shape of the crushing parts Cone crusher with sharp-angled crushing cone (coarse and medium crushing) Obtuse cone crusher (medium and fine crushing) – Symons  Cone crusher sharp-angled crushing cone https://www.youtube.com/watch?v=2iZS0ZdEG5c https://www.youtube.com/watch?v=c0UV0ArYMAg  Cone crusher A crushing cone is inclined on a fixed rotating shaft. The cone on the shaft performs a circular rocking movement, which causes the inner crushing cone to alternately approach and move away from the outer shell and crush pieces of ore in the space between the crushing cone and the cone shell. The shaft is rotatably mounted in a ball bearing and its lower end is mounted in an eccentric sleeve. The housing is rigidly connected to a bevel gear, into which the second bevel gear on the horizontal drive shaft engages. The grooved shell of the crushing cone as well as the outer fixed cone is made of manganese steel. To change the gap between the crushing cone and the outer cone shell, the shaft can be moved up with the adjusting screw. Large modern crushers have this slot adjustment hydraulically secured.  Cone crusher Crushed ore falls through the gap between the cone and the outer cone shell onto sliding surface 10 and out after it. The drive is via a free pulley 11, which is connected with locking screws to a firmly inclined pulley 12 on the shaft. If an unwanted very hard object enters the mouth of the crusher, it will cause a sudden resistance, the locking screws will break and the free pulley will rotate independently of the crusher. Thus, the crusher is protected against breakage and deformation of valuable parts. The power of the crusher depends on the size of the crusher, the speed and the degree of crushing, which is usually 5 to 10. Cone crusher Obtuse cone crusher Cone crusher  Cone crusher https://www.youtube.com/watch?v=c0UV0ArYMAg Cone crusher Cone crusher Difference between jaw and cone crusher CC JC larger crushing space easier filling of input works fluently material less energy consumption easier maintenance, use full rotations for faster, less expensive crushing smaller building space do not pass uncrushed discharge slot regulation cone surfaces easier, manganese steel the stage of crushing is wear can be returned higher  Roller crusher Roller crushers: coarse and medium crushing Crushing parts: two smooth, grooved or toothed rollers that rotate against each other They are included in the line between jaw and cone crushers The ratio of the diameter of the roller to the largest crushed pieces is important for the crushing process The diameter of the rollers should be 20 times the largest pieces before crushing. Large pieces slip in front of the rollers and cannot be caught by the rollers. The capture angle should not be greater than 25o, on average it is 16-18o Roller crusher Roller crusher Roller crusher Roller crusher  Hammer crusher Principle: the material is crushed by the impact of crushing bodies - hammers, which are loosely connected to the rotating rotor, further by throwing pieces of rock by centrifugal force onto armor plates and by bumping the pieces against each other Construction: crusher body with grate Rotor Hammers are made of Mn steel Hammer crusher  Hammer crusher Hammer crushers with rollers for crushing sticky materials (clay minerals and materials with high water content) the solid wall is replaced by rollers the movement of these rollers prevents sticking of the processed material and at the same time helps the progress of the material to the exit slot  Hammer crusher Hammer crushers with rollers Hammer crusher Hammer crusher Hammer crusher Hammer crusher  Impact crusher Impact crusher they crush the material by hitting the rotating impact bars rigidly connected to the rotor and bouncing off the stable rebound plates fixed on the inside of the crusher cover they are designed as single-rotor or double-rotor unlike hammer crushers, the lower part of the crushing space is not closed by a grate, but is open Impact crusher Impact crusher  Questions from lecture 4 1. What is the purpose of diminution? 2. Define stage of crushing and what purpose does it have during grinding 3. What are the principles of crushing according to the method of mechanical action of forces? 4. Describe the principle jaw crusher. 5. What is important for crushing process with roller crusher? 6. What is the division of jaw crushers according to construction?  http://www.ami-crushers.com/videos/ https://www.youtube.com/watch?v=njRvrT62 kIs https://www.youtube.com/watch?v=4TlA51Pn qYo  Principles of crushing In practice: a large number of different types of crushers Ball mills - the material is crushed by falling balls and spreading Wheel mills - the material is crushed and spread by treads rolling over the surface Thank you for your attention  Technical University in Košice Faculty of Materials, Metallurgy and Recycling Institute of Recycling Technologies Fundametals of Mineral Dressing Study programme: Waste treatment and recycling Lecturer: Assoc. Prof. Dušan Oráč, PhD.  Lecture 5 Content 1. Grinding, grinding principles 2. Division and characteristics of mills.  Goals of the lecture 1. Define the difference between crushing and grinding 2. List the basic types of mills. 3. Describe the working principle of a ball mill. 4. Define the term optimal grinding during grinding 5. Determine the difference between the grinding speed modes of the ball mill. 6. Compare the advantages and disadvantages of a ball mill and a rod mill 7. Describe the work of the so-called Harding's Mill 8. Clarify the term autogenous grinding  Grinding Grinding - the finest separation of ores before their separation (most often by flotation) In generally ore is grinding below 2 - 3 mm (< 0.075 mm flotation fineness) Mills: Ball mills, rod mills - the material is crushed by falling balls (rods) and spreading Wheel mills - the material is crushed and spread by treads rolling over the surface Vibrating, nozzle-mills for very fine grinding Basic types of mills a - ball mill with sieve and casing b - ball mill with output through a hollow pin (inlet) c - ball mill with grate d - tubular ball mill e - multi-chamber tubular mill f - rod mill g - Harding's conical ball mill h - "Aerofall" mill i - vibrating mill  Basic types of mills Ball mill with sieve casing - it consists of a rotating perforated cylinder and from the stable drum casing that it has at the bottom take-out hole. It is used for dry grinding. Ball mill with discharge through a hollow pin– is characterized by the fact that the inner diameter of the drum is approximately equal to the length of the cylindrical part of the mill. The ground material falls through the hollow delivery pin. Ball mill with grate it has a built-in compartment on the output side of the drum with holes and blades for material removal to the take-out pin  Basic types of mills Ball tube mill – has the length of the cylindrical part several times greater than the diameter. This ensures a longer stay of the material in the mill, and thus a finer grinding. Multi-chamber tube mill – it is designed for multi-stage grinding in grinding chambers Separated from each other by perforated partitions. In the individual chambers, spheres are used in stages decreasing dimensions. Rod Mill - It uses cylindrical rods as grinding bodies and has a larger diameter output pin as a ball mill  Basic types of mills Conical Harding Mill – it has a relatively short cylindrical part and conical front walls Mills for autogenous grinding (Aerofall) – has a large diameter D in relation to the length of the cylindrical part. The grinding bodies are large pieces of ore 300 to 600 mm. The ground product is carried out by an air stream. Vibrating mill – is a ball mill whose sprung drum body performs an oscillating motion. Grinding bodies (balls or bars) they fill up to 90% of the mill's volume.  Principles of ball mill work The path of the balls depends on the speed of rotation, so it is important to determine the correct number of revolutions of the mill. The balls are held on the inner circumference of the mill and are carried by it as long as the centrifugal force Fo is greater than the centripetal component of the ball's gravity G.cos  The relationship applies to the centrifugal force Fo v2 Fo = m r Centripetal component C of the mass of the ball G (kg) r-radius of the peripheral layer of spheres (m) r1-mill radius (m) G = m. g  Principles of ball mill work and the angle  according to the relation C=G.cos α = m.g.cos α The balance of forces implies: v2 m = mg cos  r This equation reaches a maximum value for =9 in the form 2 v = g.r The relationship between peripheral speed and the rotation frequency n is expressed by the equation .r.n 42 ,3 v= n= 30 D By fitting and adjusting: where D is the inner diameter of the mill drum v- is the peripheral velocity of the center of the sphere (m.s-1), n- operating speed (min-1)  Principles of ball mill work 42 ,3 In equations n = operating speed n express D maximum, critical speed, that is n = nkrit. By exceeding the critical speed, the balls are pressed against the wall of the drum with such a centrifugal force that it carries them away - they do not fall off. In order for grinding to be effective, the revolutions of the mill must be lower, i.e. n = (0.75 – 0.80)ncrit.  Principles of ball mill work The critical number of rotation speed is the rotation speed of the mill at which the centrifugal force cancels the influence of the earth's gravity, which acts on the grinding balls. As a result, the grinding bodies do not fall and perform no useful grinding work. Grinding speed modes a - cascade, b - mixed, c - waterfall  Grinding speed modes Cascade mode – it occurs at relatively low mill speeds. Grinding balls or rods are carried to a certain height A above the center of the mill O and roll along the surface AB inclined at an angle  to the horizontal plane. In this way, the movement of grinding bodies occurs on closed trajectories, e.g. ABCDA. A dead zone or "core" is created in the center of the ball cartridge where the balls do not move. Cascade mode is common in rod mills, as rods falling from a greater height can create failures due to their prevention. In ball mills, this mode is applied during dry grinding in tube mills. For fine grinding.  Grinding speed modes Mixed mode - is such when the balls are in free fall on part of their path AFB and on the next section BC they move by rolling. Even in this mode, a stationary core is formed around which the other spheres circulate Waterfall (cataract mode) - is when the balls are raised to a greater height at higher rotation speeds, and then freely fall along variable paths. In this mode, the core is formed only to a small extent. This mode is used when grinding coarser grinds, where the principle of comminution is mainly applied by the impact of falling grinding bodies and partial spreading. Grinding of coarse-grained ore. Ball mills  Ball mills Drum ball mills with discharge through a hollow pin construction : – barrel – front covers with hollow pins – lining of barrel: plates from C, Mn, CrMo, Ni steel – Steel or cast iron balls of various diameters (up to 150 mm) – the lining boards have a different profile – smooth or ribbed inner surface – Inlet: the largest grain size of 20 mm ores and mineral raw materials, – Output: after grinding 1 to 0.06 mm – D - inner diameter of the shell without lining 900 - 4500 mmL- working length of the barrel 900 - 8000 mm  Ball mills Barrel ball mills with discharge through a hollow pin A ball mill with material discharge through a hollow pin consists of a drum 1 and front lids 2, which have hollow pins 3. With the help of these pins, the mill is placed in the main bearings 4. The drive of the mill is ensured through a pinion wedged on the drive shaft, which engages in the gear ring at the end of the drum 6. The drive is carried out directly, or by connecting the drive shaft to the slow-speed electric motor using a clutch, or through a gearbox, if a motor with a normal speed of 12 is used. The mill is filled through the filler 7 and the hollow pin of the lid 3 with the replacement neck 8. The fillers can be barrel construction, spiral construction, or combined. The drum filler is a partly cylindrical and partly conical chamber, at both ends open inside it has a spiral compartment for feeding the material to the mill through the input pin.  Ball mills Barrel ball mills with discharge through a hollow pin On the front side of the filler, where the ore is fed, a lid 11 in the shape of a truncated cone with a circular opening is attached to the body of the filler, through which the ore is fed to the spiral of the filler. The filler is fixed with screws in the input pin of the mill. Between the body and the lid of the filler there is a metal partition 10 with a cut-out through which the ore is fed to the spiral of the filler. The spiral filler has a spiral-shaped scoop with a circular opening in the side wall, through which the scooped material exits the filler through a pin into the mill. The combined filler is a combination of drum and spiral filler. It is used when coarse ore from the reservoir and sand from the classifier, which works with the mill in a closed circuit, are fed into the mill at the same time. After grinding, the material exits through the neck 9, which is fixed in the hollow pin of the lid 2.  bu 1- barrel, 2- front covers that have hollow pins-3, 4- bearings, 5- steel or rubber insert, 6- toothed ring, the mill is filled through 7- filler in which there is 8- replacement nozzle, 9 - output nozzle of material, 10-sheet metal compartment with cut-out, 11-filler lid 12-motor  https://www.youtube.com/watch?v=HdY6Tuo 3AKU https://www.youtube.com/watch?v=L6sgGXX YdEU https://www.youtube.com/watch?v=zUtQZtfV JN8 https://www.youtube.com/watch?v=vGo2KQb i31A  Ball mills Ball mills with sieving casing They have a short cylindrical grinding space, partly formed by perforated grinding plates. The grinding filling is made of steel balls. At the same time as the grinding plates, the outer screen casing rotates, onto which the sufficiently ground material falls, while the coarser material is returned to the interior of the mill by backward- acting blades The material is fed through a pin at the head of the mill, the ground material is removed at the bottom through the mill shell. The mill works dry and is intended for grinding various materials to a grain size of around 2 mm The effect of ground material on the grinding process: The smaller the grai