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By J Johansson

The aim of this paper is to discuss how to form work and organisations in the mines of the future. The Kiruna underground iron ore mine in the far north of Sweden is used as an example on how technical development affects organisational issues like skills, work identity and gender. Over a period of 50 years one can see a transformation of work from manual underground work to automation and remote control from surface level. What characterised the old underground workface was the close relation between man and the hard rock and with arduous physical work under dangerous conditions. Today, the face miners are located on the seventh level of an office building close to the mine. There is also an emerging, and in many aspects already evident, knowledge transformation û from the old and obsolete physical and tacit knowledge and skills (for example the ability to æread the rockÆ) to something new, which can be described as abstract æhigh-techÆ knowledge and skills. The modern technology has created a new type of work û new in terms of competencies and knowledge as well as workload and organisation. At the same time the mining company are recruiting more women and promoting the former pure male work as attractive workplaces for both women and men. All this has effects on how individuals and company create and recreate skills, identity and gender. To some extent the technological development predestines these changes, but there are some choices to be done when forming good work and organisations for the mines of the future. The traditional mining workplace culture and behaviours and the old type of masculinity, the æmachoÆ style, will be challenged by the new æhigh-techÆ work and new competency demands. The changes risk meeting restoring responses, which can have negative impact on the performance of the organisation, for example making it inflexible and perhaps ælaggingÆ behind the technological development. These questions need to be handled when planning future mining.

Jan 1, 2008

Chelopech Mining EAD and Best Available Techniques for Management of Waste Rock in Mining Activities

Sep 13, 2010

Concentrations of bright green material in the "Golden Mile" of Kalgoorlie, which carry particularly high gold values, are known locally as "green leader".This assemblage consists largely of quartz, sericitic muscovite, carbonates, and pyrite. Some of the sericitic muscovite contains vanadium, giving the rock its green colour. Vanadium oxides, including nolanite, are also present. Tellurides identified in this study are calaverite, altaite, petzite, melonite, and coloradoite. Native gold was found in most of the samples; some of the gold, at least, has been formed from the decomposition of gold tellurides.It is suggested that mineralizing solutions carrying gold and tellurium leached vanadium from the host rocks and subsequently deposited gold tellurides and vanadium-bearing minerals in the "green leader".

Jan 1, 1977

By Vaughan J. P

The Pegmont deposit is a stratiform Pb-Zn sulphide body occurring in a thin, iron-rich metasedimentary unit situated near the top of the Kuridala Formation, a part of the Mary Kathleen Group of the Middle Proterozoic"Eastern Geosyncline" succession of the Mount Isa-Cloncurry district. The deposit appears to have developed in a shallow basin or depression on a sea or lake floor.Detailed chemical and mineralogical study of seven diamond drill cores through the ore horizon shows that in addition to galena and sphalerite the orebody contains a large range of iron-rich silicates and aluminosilicates.Further, five drill cores selected to represent a section from basin centre to basin edge exhibit clear and systematic chemical and mineralogical changes in the ore horizon in both a vertical and, most importantly, ill a lateral sense.Reconstruction of the sedimentary environment of the ore horizon as a whole shows this to be a silicate facies of a phosphatic, manganiferous iron formation or, more accurately, of "ironstone" in the sense of James (1966, U.S. Geol. Surv. Prof. Paper 440, chapter W).On the basis of both mineralogy and chemistry this silicate facies may be subdivided into three microfacies according to the dominant iron silicates characteristic of each: a fayalite microfacies, a hornblende-clinopyroxenemicrofacies, and a garnet microfacies. Significant Pb-Zn sulphide concentrations are confined almost entirely to the fayalite microfacies.

Jan 1, 1979

By W P. Darcey

Jabiru Metals completed a feasibility study on the Jaguar Base Metal Project in July 2005. The study was based on conventional truck haulage via a decline. Conveyor haulage was considered but not in sufficient detail to provide a meaningful comparison. The current study investigates the cost and productivity of alternative ore transport systems for the Jaguar project. The options considered are conventional underground truck, conveyor, road train, rigid frame truck, monorail haulage and shaft hoisting. Shaft hoisting was not considered in detail due to the high capital outlay for such a relatively short mine life of less than six years. This study goes beyond the common approach of evaluating haulage systems in isolation; it includes development costs, timing of ore production and costs associated with mine services as well as administration and milling costs. The results of this study indicate that the best haulage option for the Jaguar project is conventional truck using the Hitachi AH400 trucks. The net present value (NPV) for this option is A$8.13 million higher than the next best option namely the Kiruna E635 electric truck. The conveyor option has the lowest operating cost per tonne of ore but the longer development time negatively impacts on its NPV. The monorail option is considered impractical due to the number and length of trains required to achieve production targets.

Mar 21, 2011

By M I. Pownceby, W J. Bruckard

A South African chromite sample was subjected to characterisation and physical beneficiation testwork in order to assess its suitability to produce an upgraded chromite product with a silica level of <1 per cent SiO2 and a chromite level of >46 per cent Cr2O3. Chemical analysis by XRF indicated that the bulk material had a Cr2O3 content of 40.5 per cent w/w and a SiO2 content of 7.5 per cent w/w. Combined XRF analysis with sizing data showed that the majority (~70 per cent) of the siliceous material was present in the +600 ¦m fraction while ~70 per cent of the Cr2O3 was in the -600 ¦m fraction. Qualitative mineral phase analysis by XRD indicated that the sample mineralogy was dominated by ferrian-magnesiochromite spinel ([Fe,Mg]Cr2O4) and aluminium-chromite spinel (Fe[Al,Cr]2O4), with enstatite (Mg2Si2O6), haematite (Fe2O3) and anorthite (CaAl2Si2O8) as minor phases. SEM and EMP characterisation showed that the silica was mainly present in discrete enstatite grains but lesser amounts were also present as the high silica phases plagioclase and enstatite on the edge of grains. Wet gravity separation performed on sized fractions (-600+106 ¦m size range) from the -2.0 mm (primary) ore as well as the ore that had been crushed to pass 0.6 mm (secondary) showed that stage crushing of the -2 mm +600 ¦m fraction followed by wet gravity separation upgraded the Cr2O3 grade at 70 per cent Cr2O3 recovery from ~44 per cent Cr2O3 in the primary material to 46 per cent Cr2O3 (the target grade specification) in the secondary sample. It also showed that the stage crushing of this +600 ¦m fraction at a cut-off level of one per cent SiO2 increased the cumulative Cr2O3 recovery from ~50 per cent in the primary material to ~63 per cent in the secondary sample in the same size range of -600+106 ¦m. The extent to which additional crushing could lead to improved chromite recoveries at the required chromite and silica grade target specifications was not determined. This experience demonstrates that prior to processing test work being conducted, a thorough understanding of the chemistry and mineralogy of the test sample promotes efficient and targeted processing research.

Jan 1, 2008

By T Barto, D Thomson, T Norgate, C Doblin

Collaboration between CSIRO Minerals and SunSalt Pty Ltd, a salt producing company located in rural Victoria, has resulted in a commercial process to recover magnesium sulfate (commonly called Epsom salt) from the saline waters of the Murray Basin. The feed for this process is bittern; the liquor remaining after halite (common salt) has been harvested from the saline water by evaporation.SunSalt produces salt and bitterns from three locations, namely Hattah (Victoria), Mourquong (NSW) and Wakool (NSW). The small size and considerable distances between these operations makes it uneconomic to build a stationary processing plant to extract value-added products, in particular Epsom salt, from the bitterns of the three operations. This fact led SunSalt to build a containerised mobile plant that could be moved to each site to process the bitterns at the end of the salt harvesting period.Epsom salt is extracted from the bittern by further evaporation, refrigeration and recrystallisation. In this process the bittern is diluted with five per cent volume of fresh water to minimise precipitation of residual halite in the bittern. Cooling the diluted bittern to between -5 and -10¦C precipitates up to 70 per cent of the magnesium sulfate, which is recovered as 85 to 96 per cent purity Epsom salt by filtration. This product is marketed as an industrial grade Epsom salt. Higher purity (up to 99.9 per cent) Epsom salt (USP or BP grade refined product) is made from the industrial grade product (raw Epsom salt) by recrystallisation.The containerised mobile plant was commissioned in December 2002. The raw Epsom salt generated in the mobile plant is refined to a higher purity Epsom salt in a separate plant located in Mildura. The Mildura plant was commissioned in December 2003.The CSIRO-SunSalt collaboration has demonstrated that the saline waters can be processed into a useful resource, and in addition could create jobs and a new skill base in regional Australia. The production of Epsom salt locally in Australia, which is worth currently about $A600 per tonne, removes the need to import over 3000 tpa from overseas with a net positive impact of $A2 million on the balance of trade.

Jan 1, 2004

By C Thompson, D Connelly

The history of mill liners has evolved over time and this paper tracks the changes and development of liner technology. It provides an overview of the primary types of liners, the design and the materials of construction. The design of a mill liner is driven by application, materials of construction, casting technology and handling issues. The choice of solid steel, grid liners, rubber or composites and magnetic liners is based on many factors.The methods used for monitoring wear and predicting eventual change out time are many and varied. The contribution of discrete element modeling (DEM) analysis in predicting wear profile is discussed.Mill trajectory and DEM software programs are used with great effect to predict the effect of lifter height, face angle, high low lifters or mill speed. In the field, trial and operational experience is used or improvements/design concepts at one operation are applied to another. Broken mill lifters, accentuated wear and other problems can be better understood using hardness testing, chemical analysis and photo micrograph analysis of pearlitic or martensitic structure along with fracture face observations. This forms a part of the typical root cause analysis. However given correct and sound liner and lifter, feed and discharge design media selection, and materials of construction, the majority of premature liner or bolting failure is normally attributed to incorrect operational methods such as excessive high ball to feed ratio, incorrect mill speed relating to lifter ball throw, incorrect media selection, "tramp" material entering the mill charge from upstream or recirculating process and understanding the specific mill operation in question.It is hoped that this paper will benefit mill operators who are faced with challenges of improving wear life and at the same time optimizing mill throughput and performance.CITATION:Connelly, D and Thompson, C, 2013. The selection design and application of mill liners for large wet grinding mills, in Proceedings MetPlant 2013 , pp 133-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

A slag-metal equilibrium study of the system SnO-FeO-(Si02+Al2O3)/Sn-Fe was carried out at 1250°C. The distribution coefficient, k =(Sn/Fe)metal X (Fe/Sn)slag was found to range from 246 for an iron contentof 0·53 per cenrt in the metal to 82 for an iron content of 6·4 per cent. The value of the ratio ?SnO/?FeO was calculated and found to be approximately a function of per cent SnO in slag alone in the region (Si02+Al2O3)/ FeO = 0·4 to 1·2. Comparison with other published work suggests that the addition of CaO to slags having (SiO2+Al203)/FeO ratios of about 1·1 raises the value of ?SnO/?FeO...

Jan 1, 1974

The Mount Lyell Company's concentrating mill is situated about a quarter of a mile westward of the portal of the North Lyell tunnel, which serves the North Lyell, Royal Tharsis and Crown Lyell mines, being on the 1100-ft. level of the first named. The Comstock mine is connected with the tram system at this level by five and a half miles of steam tramway, two-foot gauge being standard throughout.The plant is well placed with regard to all essential services and has an excellent water-supply from a series of three dams on the West Queen river.MILLING ORESThe mill feed is a mixture of the outputs from the foUr mines mentioned, each of which has its characteristic ore, but, generally speaking, about half of the ore consists of siliceous schists and the other half of hard grey quartzite. The schisty ores are easy to crush, but, on grinding, while the schist slimes readily, the quartz granules are hard, resulting in the handling of heavy loads on the secondary classifiers. The quartzite ores are both hard to crush and difficultto grind.The principal sulphide materials are bornite, chalcopyrite, and pyrite, chalcopyrite being the main copper-bearing mineral.The crystallization is coarse in the schisty ores, but it has been shown that even the 200 mesh (Tyler) material contains included sulphide particles. At the present time the sizing of the final tailing averages 80% through 200 mesh.

Jan 1, 1932

By J Samosir, L Snyman

Northparkes was the first mine in Australia to use block cave mining method which relies on gravity and natural rock stresses to fragment and recover the ore. It was also the first hard rock mine to use hydraulic fracturing, in conjunction with CSIRO, to promote caving of E26 Lift 1. The technique was later used on E26 Lift 2 wedge and E48 prior to undercutting.Northparkes production is currently sourced from the E48 Lift 1 block cave mine and E26SLC. The E48 block cave contains economic ore to the north and south of the current cave footprint. To recover this ore the footprint has been extended on the north and south with two extraction drives and one extraction drive, respectively. Modelling of cavability above the additional drives indicated that the cave would not readily propagate to a sufficient height of draw to mobilise the ore and tended to arch over into the existing cave. To address the modelling results and to reduce the risk of the project, rock mass preconditioning was adopted.This fracturing campaign was performed from surface drill holes adjacent the subsidence zone angled to intersect the higher grade and higher elevation ore zones.Optical televiewer surveys, run prior to fracturing, picked intervals and fault zones to be avoided. Holes were resurveyed post-fracturing to detect newly created fractures and as a measure of success of the program.During fracturing operations water and gel fractures were run at varying depths and pumping pressure was logged for each fracture. The mine seismic system monitored significant events and dye in the fluids utilised for tracking water inflow locations during underground inspections.Towards the end of the project, guar fibres from gel were detected within the mill circuit and required treatment to resume optimum processing.CITATION:Webster, S, Snyman, L and Samosir, J, 2016. Preconditioning E48 cave extension adjacent to an active cave, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 471–478 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By R S. Hamilton, S R. Grobler, M E. Greenway

The progressive development of underground mines frequently requires increased ventilation flow rates through mine shafts that were originally designed for lower rates. Where these shafts are equipped with conveyances running on rope guides, the higher air flow rates adversely affect the lateral motion of conveyances and could cause conveyances to collide with the shaft walls or with one another. Hence the safety impact of higher flow rates requires proper assessment. This can be undertaken by use of computer simulation models to predict the dynamic motion of the conveyances during hoisting. It can also be undertaken entirely by field testing, or using a combination of simulation and field testing. This paper discusses these techniques and makes cautionary remarks about setting an absolute generic maximum flow velocity for all shafts. Approaches to assess existing shafts for increased ventilation flow rates are also discussed.CITATION:Greenway, M E, Grobler, S R and Hamilton, R S, 2017. Safety impact of increased shaft ventilation on rope guided conveyances, in Proceedings Australian Mine Vent Conference 2017, pp 261–270 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

Agglomeration for Copper Heap Leaching Agglomeration of ore is a method which can be used to eliminate the migration of fine grained particles throughout a leach heap. Without agglomeration, fine ore particles are able to migration within the heap, clogging flow channels and producing large areas where access of the solution is poor. In order to gain the benefits of agglomeration and improve agglomerate strength even further in copper heap leaching, an economical, acid-resistant binder is needed. However, most binders have been used without any systematic reasoning. A set of novel testing methods were developed, including a soak test, percolation flooded columns, and larger long-term leach columns. The soak test compares the degree of breakdown when agglomerates are subjected to an acidic environment. While the percolation flooded columns and larger long-term leach columns evaluate the flow of leach solution throughout the ore bed. Systematic studies have been completed on a wide range of binders using these novel testing procedures. It was found that for a low grade chalcocite ore, which was rich in silica, from a southwest US mine, polyacrylamides reduced the fines migration the best in the novel soak test. The non-ionic binder, in particular, was found to reduce fines migration as much as 93 per cent. Several of the binders tested were shown to increase the hydraulic conductivities of the agglomerated ore up to 2.5 mm/sec, compared to a hydraulic conductivity of only 0.25 mm/sec when no binder was used. These binders also prevented 'slumping' of the ore, which indicates a decrease in breakdown of the agglomerates. The use of a binder also showed no interference with leaching reactions in long-term leaching experiments.

Sep 13, 2010

Our ultimate resources come from the Sun and the Earth System. At this time we face a world crisis in energy, water and soil resources. Global pollution problems are increasing in almost all nations. There is an urgent need to use our vast knowledge with a new wisdom and this requires new integrated teams of experts to provide the best alternatives for the needed new development problems. These teams must include economists, engineers and a broad spectrum of scientists. Today it is possible to produce clean energy, stop soil erosion, clean water and reduce and use wastes of many types.

Jan 1, 1995

CONTENTSIntroductionNorthern ExplorationDrive ConceptionGeneralDriving CrewDrive Cross Section and Track DetailsVentilation by Electrically Driven FanTemperatures and HumidityFan PerformanceRock Drill Carriage and Rock DrillsStandard Drilling RoundElectric Firing from Power MainsExplosives and DetonatorsCharging and FiringMechanical Loading and Electric HaulageOperating CycleStatisticalEquipmentAcknowledgementINTRODUCTION.The driving project described in :this paper is one of greater magnitude than usual for the Broken Hill field, and in the execution of the work a departure was made from long-established local practice by the introduction of mechanisation. The primary object of the drive is to provide sites for gaining information regarding the behaviour of the ore-bodies well beyond the limits of the present exposures.Due to thermal conditions, the major portion of the work was done on a six-hour shift basis, in contrast to the normal one of seven hours, with a five-day week.

Jan 1, 1946

By Hiddlestone D. C

Effective exploration, testing and analysis is essential for good process design and optimisation of coal preparation plants. Coal processing relies on the sizing and washability characteristics of the particular coal to define the most cost effective design to meet the market requirements. Flowsheet development and equipment selection is dependent on the natural quality characteristics of the coal, its physical properties and the value of the final product in its market. The methodology of process selection and the key elements in design are discussed. Coal is consumed in two general markets: ò steaming coal - both domestic and export, and ò metallurgical coal. This paper discusses the typical economic analysis required to evaluate the potential for, and cost benefit of, providing the flexibility to switch coals between markets. A case study illustrates the methodology of process selection in a typical high value metallurgical coal.

Jan 1, 1997

The large increase in secondary industries in this country, during the war and post war periods, has caused a shortage of capacity for the production of merchant bar.To overcome this shortage, an expansion of rolling mill facilities has been undertaken by the Broken Hill Pty. Co. Ltd. A small, but modern, merchant mill has been erected at Kwinana in Western Australia and a strip and skelp mill is under construction at Newcastle. The latter mill will roll strip and skelp at present being rolled by the Newcastle 10 in. Merchant Mill, enahling this mill to concentrate on merchant bar production.The Kwinana mill was installed to supply the Western Australian market. This state has a small population (approximately 658,000) and is not at present highly industrialised. It was necessary, therefore, to design a mill which would be capable of producing a wide diversity of sections and could be expanded as the demand increased. To begin with capital expenditure had to be kept within reasonable bounds. The design work for this mill, with the exception of a few specialised items of equipment, was carried out at Newcastle.All design work for the Newcastle mill was carried out by the lVIorgan Construction Co. of America. Although initially intended for rolling flat. products, the designers were asked to make the mill as flexible as possible, so that should the market for flat products decrease, this mill with additional equipment could undertake the rolling of medium sized sections.

Jan 1, 1957

Uranium exploration over a wide area of the Southern Frame Embayment, South Australia, has defined a number of Lower Tertiary fluvial palaeochannels incised in older rocks. The buried channels contain similar stratigraphicsequences of interbedded sand, silt, and clay, probably derived from the adjacent uranium-rich Olarv Provinee. Uranium mineralization is pervasive within two major palaeochannels, and four small uranium deposits have been found in the basal sands of these channel sequences, at the margins of extensive tongues of limonitic sand.One of the channels is examined in detail with respect to channel morphology, stratigraphy, and rock alteration and the geology and ore controls of the contained uranium deposits are described.A geochemical zonation reflected by variation in limonite, pyrite, carbon, and humic malleI' is defined across one of the deposits. A genetic model is proposed suggesting formation by a uraniferous geochemical cell which migrated down the stream gradient and concentrated uranium on its lateral margins adjacent to the channel bank.

Jan 1, 1978

By N Currey, G Corder, G Becker

"The SUSOP« Framework is a new technique that helps incorporate sustainable development principles and objectives into the design and operation of businesses. Developed through the Co-operative Research Centre for Sustainable Resource Processing, it brings a design methodology to sustainability, similar to what hazard and risk techniques such as HAZOP did for safety.Metallica Minerals Limited (æMetallicaÆ) adopted the SUSOP« framework to help identify opportunities and risks that could directly improve or affect its flagship SCONI (nickel-cobalt and scandium) project. This project has the potential to become the worldÆs largest producer of scandium oxide (æscandiaÆ) which is used in solid oxide fuel cells and strengthens aluminium alloys. Located northwest of Townsville in Queensland, the plant site will be located within the previously mined and partially rehabilitated Greenvale Nickel Mine. By applying the SUSOP« framework through a series of multi-disciplinary workshops and offline analysis, Metallica was able to identify numerous sustainability opportunities and risks. Opportunities were clustered together to form concepts to develop a more holistic understanding of the projectÆs overall potential contribution to sustainable development as well as determine where key risks could be mitigated. Four key concepts were identified: Waste and Water Workforce Community and Enterprise Development Energy and Greenhouse Gases (GHG). Metallica was able to include a range of initiatives that could deliver enhanced environmental, social and community outcomes into their mine development plan. These included measures to reduce reliance on water, reduce the volume of waste, provide local opportunities for training and skilled employment and create support for local enterprise development. These measures also resulted in a significant reduction in the capital estimate of the project.This paper provides an overview of the SUSOP« framework, details its application to the SCONI project and discusses the outcomes that will help establish the projectÆs strong sustainable development credentials and improved business outcomes.CITATION:Corder, G, Currey, N and Becker, G, 2013. Sustainability, made easy - A business improvement case study, in Proceedings MetPlant 2013, pp 259-271 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

Selective Recovery of Platinum from Cobalt-Rich Crust

Sep 13, 2010