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SITUATED in the county of Manchcster, in Northern Eyre's Peninsula, the Iron Knob ore-deposits form the basis of the industry. These deposits are connected by the Iron Knob tramway to the port of Whyalla, aal miles distant, on the western shore of Speneer Gulf,and to-day another tramway is under construction to link up with the same port, a second group of iron ore leases known as Iron Baron, which is situated 18 miles south of Iron Knob. Fig. 1 indicates the geographical relationship of these three places, Iron Knob, Iron Baron, and Whyalla, which together comprise this field of the company's activities.

Jan 1, 1930

The increasing global demand for rough materials forces almost every mine to look at the mechanisation in their processes. This will not onlyimprove performance but with safety issues becoming more and more prevalent, the need for the introduction of mechanisation technologies to mining applications is essential. Ongoing developments are occurring in almost every field, ranging from basic developments to specialised mining. Mechanical tunnelling and shaft sinking have set the standards regarding safety, profitability and environmental protection. Different machine types and working principles have been developed to suit the geological and hydrological requirements of tunnelling projects worldwide. Continuous activity in research and development leads to constant optimisation of tunnelling performance.

Jan 1, 2008

This paper describes the MillMapper technology developed for condition monitoring of liners and other operational parameters in grinding mills used for mineral comminution, by presenting a case study of its application. MillMapper provides maintenance engineers, operations managers and process and plant metallurgists with quantitative, accurate and reliable condition monitoring data for informed decision making regarding the maintenance and metallurgical aspects of such mills. MillMapper uses calibrated laser scanners for the capture of three-dimensional surface representations inside a mill during a shutdown so as to determine shell, feed and discharge liner thickness at a resolution of several million data points, a procedure that nominally takes five minutes to complete. Once several data sets over time have been collected inside a mill, MillMapper can be used for liner wear, liner wear zone, liner weight, ball charge volume, ball charge weight and intelligent profile tracking over time. Liner tracking in combination with site defined reline and failure criteria and with throughput tonnage data is utilised for change out prediction of each separate liner segment type.

Jan 1, 2008

By R Buerger, D Barrett, P Hodkiewicz

The Emily Ann nickel mine is owned and operated by LionOre Mining International Ltd. The deposit was discovered during 1997 and is blind, concealed beneath 25 m of transported cover and a further 100 m of unmineralised Archaean felsic rocks. Nickel sulfide mineralisation is hosted predominantly in strongly deformed, altered and metamorphosed Archaean komatiitic ultramafic rocks. Subordinate felsic-hosted, remobilised mineralisation is also present. Mining of ore commenced during late-2001. Since the early days of exploration drilling, through feasibility delineation drilling and subsequent mining, a geological model involving thrusting and folding of a komatiitic-hosted nickel sulfide deposit has been an evolving theme. Development of appropriate mine geology procedures, including detailed mapping, significantly increased the confidence of mine-site geology and engineering staff in the geological model and improved operational efficiencies during start-up. This also allowed the engineering and mining team to develop a tolerance for the large fluctuations in daily production grade, with an understanding that budgeted production targets, on a level-by-level basis, were achievable. This paper describes the development of the current interpretation of the deposit and emphasises the importance of a sound understanding of deposit geology. The direct benefits at Emily Ann included improvements in drill targeting, resource estimation and mine planning.

Jan 1, 2003

By A Boeing

Rock-breaker automation and remote operation improves the safety and efficiency of mining operations. This paper presents an overview of the Rocklogic rock-breaker automation system architecture that provides collision avoidance, automated parking and remote operation functionality. The system consists of a distributed computer control system that interfaces with sensors attached to the rock-breaker, the rock-breaker hydraulics and the site infrastructure. We present results of an automated Transmin rock-breaker installed in a production environment at an underground Australian mine site. The system has been in production use for over 900 days, during which there have been no reported collisions and 100 per cent adoption of the remote operation technology. As a result, Rocklogic has significantly improved the safety of rock-breaking operations and reduced the rock-breaking cycle time, thereby improving the site’s overall throughput.CITATION:Boeing, A and Douglas, E, 2014. A remotely operated robotic rock-breaker with collision avoidance for the mining industry, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 131–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By J J. Wilkinson, C J. Ha, R J. Herrington

The Pic de Fon iron oxide deposit is a potential major new source of iron ore, located at the southern end of the Simandou range in eastern Guinea on the West African Craton. The deposit is hosted by banded iron formations (BIFs) within a supracrustal sequence, which lies unconformably upon a crystalline basement. The host BIFs and shales have been metamorphosed up to staurolite-grade itabirite and phyllite respectively. Stratigraphic relationships are obscured by polyphase deformation, although the sequence appears to comprise a lower phyllite(-minor quartzite) unit and transitional phyllite-iron formation overlain by three itabirite units. It is the itabirite units, selectively enriched to iron grades in excess of 65 per cent Fe (with low deleterious elements), that constitute the Pic de Fon deposit. Samples acquired from exploration diamond drill holes and outcrop across the deposit have been collected to investigate the Pic de Fon lithologies and iron-rich material types. Initial research techniques have included geological mapping, reflected light microscopy, x-ray diffraction (XRD) studies and ICP-AES geochemistry. The aim is to develop a model for deposit genesis that may assist future exploration and deposit exploitation planning. Results to date have identified a variety of hematite textures, which include recrystallised trellis, interlobate and granoblastic hematite after magnetite. In addition, fine-grained bladed to acicular microplaty hematite appears to both replace itabirite banding and infill porosity. Field relationships indicate a structural control of microplaty hematite development. Geochemistry and XRD results suggest a loss of silica with negligible iron addition during the conversion of itabirite to ore grade mineralisation. The enrichment process(es) is also accompanied by a gradual increase in K, Mg, Na, (Ca and Al).

Jan 1, 2005

By I F. Wood

Planning for flooding and assessment of flood impacts are important requirements for mining projects, as they are also for other types of development. With more intense development and concern from the community, supported by government regulatory requirements, assessment of flood concerns and impacts has become of increasing importance. To ensure that flooding issues are fully understood and results presented in an appropriate format, advanced hydraulic analysis procedures have been developed and are beginning to be applied. These procedures must be rigorous in an engineering context but the results must also be readily understood by the community and government agencies. Advanced two-dimensional hydraulic modelling is becoming accepted as an important means of assessing flooding issues for mining projects. With presentation of results from hydraulic models with Geographic Information Systems (GIS), flood impacts can be analysed rigorously and presented clearly. This paper discusses the application of advanced hydraulic modelling in the planning and impact assessment of a major mining project located on a floodplain where there is extensive inundation. The analysis provides for both input to the planning of the project and for detailed assessment of potential impacts. This case study illustrates some important aspects of the application of hydraulic modelling using a two-dimensional modelling to a critical flood design.

Jan 1, 2003

By G Yeowart, P D. Munro

The Prominent Hill copper-gold concentrator of OZ Minerals Limited in South Australia was built in 2008 and commenced commercial production in early 2009. It has a design ore throughput of eight million tonnes per year (Mt/yr). While the flow sheet has many items in common with other plants treating ores from iron oxide-hosted copper-gold deposits, the Prominent Hill concentrator also has some unique features. Plant design has been based on a 'template' of the very successful Ernest Henry concentrator. Initial options considered for processing Prominent Hill copper-gold ore are briefly examined as well as potential complications arising from the presence of a considerable tonnage of 'gold-only' material present in the deposit. Metallurgical test work and the subsequent decisions leading to the selection of a conventional crushing, semi-autogenous grinding (SAG) and rougher flotation circuit is discussed. One particular difference with other plants treating this ore type is that metallurgical tests and mineralogical studies identified that rougher concentrate had to be reground to a P80 of 20 - 25 microns or finer for adequate liberation of fluorine-bearing minerals. Subsequent satisfactory separation of fluorine-rich gangue material from the valuable copper sulfides requires highly efficient cleaner flotation to make a commercial quality copper-gold concentrate. Xstrata Technology's IsaMillÖ and Jameson Cell technologies developed to meet similar taxing fine grinding and flotation duties for the treatment of the refractory zinc-lead-silver ores of the Carpentaria-Mount Isa Mineral Province were selected for regrinding and cleaner flotation. Plant design has features aiding ergonomics for ease of operation and maintenance not commonly seen in recent projects with large sulfide flotation concentrators.

Jan 1, 2009

By A Whaanga, A Doecke

The internal stratigraphy of the Marillana Creek palaeochannel Tertiary channel iron deposits (CID) in the Hamersley Province of Western Australia was initially defined in the 1980s and redefined as the Marillana Formation in the early 2000s. Recent drilling, open pit mining and field observations in the Western deposits at BHP Billiton Iron OreÆs Marillana Creek tenements have revealed some additional details on the extent and detail of some units of the Marillana Formation stratigraphy in this area. The drill hole data at Western 1 South has identified a number of features either not previously documented in this area or whose significance has not been adequately recognised, including a denatured zone at the base of the Upper CID of the Barimunya Member, and variations in the lithology within the Munjina Member at the base of the channel. Additionally, the Western 4 pit walls show evidence of a significant near-surface clay horizon and overlying CID, which are suggested to be the equivalent of the Iowa Eastern Member in the Eastern deposits. The deposition of this unit was most likely driven by a regional climatic disruption rather than a change in sediment source area alone. The nature of the Weeli Wolli Formation-derived goethitic peloids in the Western deposits may explain the more extensive denaturing in the Western Lower CID of the Barimunya Member. In contrast, the more robust nature of the haematitic-cored pelletoids in the Central and Eastern deposits has resulted in a less denatured Lower CID in these areas. Such work reveals the value of and need for geologistsÆ ongoing face mapping observations and detailed drill hole logging, and cautions against not querying previously accepted interpretations.

Jan 1, 2007

This paper attempts to draw together the experience of over 30 years of research and practice in the United Kingdom on the rehabilitation of abandoned metalliferous mining wastes. The reliance on water when the mines were operating has implications for water quality and the techniques used to restore sites to alleviate the principal impacts of the mines. Drivers of reclamation included concerns about human health from wind blown dust and pollution of watercourses as well as perceptions of dereliction. Techniques of reclamation used involved removal of spoil from near to surface watercourses, capping of spoil, diversion of watercourses, use of impermeable membranes, prevention of surface sinks into underground workings and the use of constructed wetlands. The issues to be dealt with in mine reclamation have become more complex and sometimes diverge. The schemes in the 1990s described have been effective in dealing with pollution from spoil heaps and small but significant adit discharges; however, significant issues, particularly those of large flows of polluted water from mine sites, still need to be dealt with. Although the paper describes the legacy of mining, which largely finished in the late 19th/early 20th century, similar issues but on a larger scale are to be found in more recent mining, for example Eastern Europe. In many of these areas minerals still remain to be won and dealing with this legacy may fall on new mining developments.

Jan 1, 2006

By P Collins, C Sheriff

The Sand Queen gold mine is a typical Archaean narrow, high-grade gold quartz lode deposit within a shear hosted system. Initial mining during 1904 - 1948 produced 181 659 ounces of gold from 248 564 tonnes of ore milled at an average production grade of 22.7 g/t Au, which equates to a minimum of 750 ounces per vertical metre. The current mining operation is using the old Sand Queen main shaft to access the Sand George deposit, which is a narrow quartz lode system discovered in the same shear structure along strike to the south of the Sand Queen mine workings. Current underground resources contain 360 200 tonnes at a grade of 11.8 g/t Au for 136 500 ounces. Mining is scheduled to produce 20 000 ounces of gold annually. Re-opening of the Sand Queen mine and underground development of the Sand George lodes has revived several grade control issues relevant to a narrow, ænuggettyÆ gold lode mining environment. These include the dependence of assay grade of individual samples upon a number of factors, including how and where a sample is collected, how and where it is analysed, and how grade data is used to estimate an æaverageÆ grade. Ideally, the only way to achieve an acceptable estimate of ætrue gradeÆ is to mine and mill a large parcel of ore (eg >100 tonnes) from each lode or ore type. In a mining operation producing relatively small tonnages from a number of separate ænuggettyÆ gold lodes, availability of resources and operational constraints may preclude intensive sampling for predictive grade control. At the Sand Queen mine, one of the key issues has been to establish a reliable system for estimation of gold grade with which to reconcile milling data. Extensive use has been made of detailed geological data to understand the grade distribution within individual lodes and between lodes, so as not to rely solely on assay results.

Jan 1, 2008

By G W. Wilson, P Ritchie, N A. Currey

The design and rehabilitation of potentially acid forming (PAF) waste rock dumps is site specific, being a function, among other factors, of the rock types, the dumping and storage method employed, and the climatic setting. The æstore and releaseÆ cover system developed to manage acid rock drainage (ARD) from mineralised waste rock dumps at Kidston Gold MinesÆ open pit operations in the semi-arid climate of North Queensland, Australia, has been monitored for seven years. The paper describes the philosophy behind the design of the PAF dump and æstore and releaseÆ cover system and the adaptation of the cover system over time to suit KidstonÆs conditions. The results of monitoring over the seven years since the first cover was constructed are presented, and the approach being taken at Kidston to ensure that the risk of impacts from any residual ARD is accommodated and to facilitate lease surrender are described. The Kidston story is a valuable case study of a successful approach to remediating an identified source of ARD in a semi-arid climate, which has actively engaged all Stakeholders.

Jan 1, 2003

Level measurement of underground orepasses is important. Orepasses are not only utilised to funnel ore to the shaft skip loading station but also as silos for storing of ore in order to smooth out ore flow in a shaft system. Safety and operational efficiency are also improved as proper orepass level measurement could prevent overfilling of tipping areas. A study was therefore commenced to determine alternative technologies available as well as identifying practical installations across the Anglo American plc Group. From an instrumentation perspective an orepass system is an extremely difficult environment to take measurements in. Factors like dust, vapour, interference, bridging, wear and physical installation have to be taken into account. The study discusses time-of-flight (ultrasonics, radar and laser) measurement techniques followed by other possible solutions. These solutions included strain gauge measurement, the æjumping monkeyÆ technique, radiotomography, fibre optics and very long baseline interferometry (VLBI). Finally, various South African suppliers have been approached in order to determine instrumentation that is available for orepass level measurement in the marketplace. These recommendations were verified, where possible, by visiting the claimed installations.

Jan 1, 2005

By R Frew, E Wong, G Ferguson

The Chang Jiang Tunnel and Bridge Project, when completed, will provide a fixed link between ShanghaiÆs rapidly developing Pudong District and Chong Ming Island, situated in the Yangtze River delta. The link includes 7.5 km of bored tunnel from the Pudong to the intermediate Changxing Island from where the link comprises viaduct and a cable stayed bridge. The bored section comprises twin 13.7 m internal diameter segmentally lined three-lane highway tunnels. At its deepest point the tunnel will be 55 m below the river. Cross passages will link the two bores for passenger evacuation. Tunnel boring commenced in October 2006 and is scheduled for completion in mid-2009. The paper describes the key features of the design and construction of the bored tunnel by two 14.53 m diameter slurry TBMs and eight cross passages using ground freezing techniques in alluvial sediments. A decision to include light rail below the road deck was taken after the completion of the detailed design. This posed a number of design challenges including passenger evacuation to the road deck, and the redesign of the low point sumps. The various options considered are discussed together with those adopted for construction.

Jan 1, 2008

By R C. Morris

The channel iron deposits (CID) (Ramanaidou, Horwitz and Morris, 1991; Morris, Ramanaidou and Horwitz, 1993; Ramanaidou, Morris and Horwitz, 2003; Morris and Ramanaidou, 2007) are one of the two major iron ore types mined in the Hamersley Province. The CID provided around 41 per cent of the total of 268 Mt of iron ore mined from the Hamersley Province in 2006. The current CID resource is around seven billion tonnes. The CID deposits occupy numerous meandering palaeochannels in a mature surface that includes Precambrian rocks and ferruginous palaeogene valley fill. These palaeochannels are generally less than a kilometre but can range to several kilometres in width and from one metre to more than 100 m thick. The two currently mined CID areas are located:in the western Hamersley Province in the Robe palaeochannel, and in the east in the Yandi palaeochannel. These two major CID channels extend over 100 km to 150 km, with the Robe system up to 5 km wide. The granular ore facies typically contains ooids and lesser pisoids with haematite nuclei and goethite cortices, with abundant goethitised wood/charcoal fragments and goethitic peloids, minor clay and generally minimal porous goethitic matrix. Post deposition weathering is common and produced secondary facies.Ooids and pisoids were mostly derived from the stripping of a well- vegetated deep ferruginous surface. The peloids were derived both intraformationally from fragmentation and reworking of desiccated goethite-rich mud. Minute wood/charcoal fragments in the soil that were initially replaced by goethite and then dehydrated to haematite, formed nuclei for many ooids and pisoids. In addition, abundant, generally small (in situ by goethite within the consolidating CID. This profusion of fossil wood, both as ooids and pisoids nuclei and as discrete fragments as well as the local presence of kenomagnetite suggests major episodic wild fires in heavily vegetated catchments. The goethitic matrix was the result of chemically precipitated iron hydroxyoxides, resulting from leaching of iron-rich soils in an organic environment.

Jan 1, 2007

By F R. M Pires, Y Hasui, A Schrank

The iron ores of Alegria mine are composed of itabirites enclosing minor bodies of high-grade ores. The itabirites are classified according to mineralogical composition in five types: martite-rich, goethite-rich, specularite-rich, magnetite-rich and anphibolite-rich ores. The hematites are martite-rich, magnetite-rich, specularite-rich and more rarely, amphibolite-rich. Other classification criteria of the ores are based on the physical properties and the degree of compaction. As such, the itabirites and hematites can be classified as hard, friable and soft types. The mineralogical/textural evolution of the ores is linked to the pressure and temperature conditions that accompanied the tectonic processes in anphibolite facies and the different degrees of subsequent surficial weathering processes. Petrographic and microstructural studies indicate that the magnetite and amphibole bearing itabirites represent the parent rocks that created the other itabirites and that the specularite itabirites and the hard martite types are related to silica dissolution and redeposition in zones of high and low strain. Most of itabirites ores correspond to chert oxide facies banded iron formation, except the goethite and amphibole bearing itabirite that resemble a silicate or oxide-silicate facies with minor carbonate impurities. The great mass and pods of soft martite itabirites are probably shaley oxide facies BIFs with little volcanic contribution. Trace element contents of the AlegriaÆs itabirites show strong dissimilarities with BIFs associated with volcanism (Algoma type), but closely ressemble to the Lake Superior type, with high content in Cr, Co and low V, Ni, Cu and Zn. Although the absolute contents of REE present in the AlegriaÆs itabirites are, in general very low, the pattern when normalised by NASC is similar to the great majority of the Archean and Paleoproterozoic BIFs elsewhere in the world, and characterised by positive Eu anomaly.

Jan 1, 2002

The selection of the ore haulage system is one of the most crucial decisions made in the development of an underground mining project. The haulage system is, once selected, one of the components of a mine that defines its ability to respond to changes in mining inventory and the market conditions for its products. Over the last decade, in Australia at least, this selection process has largely centred on the debate over the merits of shaft and decline truck haulage. Little attention, if any, was given to the application of inclined conveyor haulage as a real alternative to the shaft and truck haulage. This is despite well established precedents for its application in the underground coal industry and some limited applications in underground metalliferous mines. This paper seeks to explore the case for the application of inclined conveyors as a legitimate ore haulage system for underground mines. The case for conveyor haulage is illustrated by an overview of the application of conveyors at some existing operations, and discussion of what conveyors have to offer as a mine haulage system and the issues that are associated with them. Material drawn from the feasibility studies for NewcrestÆs Ridgeway mine and Telfer Deeps Project is presented as case studies that considered selection of inclined conveyor haulage. The purpose of these case studies is to highlight the value of impartially approaching tasks of this type with a robust plan. This plan should be able to respond to issues identified as the task progresses towards the objective of finding the right solution for an ore haulage system.

Jan 1, 2005

By L E. Krause

This paper discusses the considerations for optimum maintenance of critical ore handling infrastructure in order to minimise the cost to the business of maintenance periods. As maintenance periods are a direct interruption to production, time is of the essence and careful management of shutdown periods is essential. The ore pass systems currently in use at Xstrata Copper û Mount Isa Copper Operations are up to 30 years old and have had significant wear over the years. The maintenance of these passes and their brows and chutes in a production situation is a challenge as it can potentially expose personnel to high risk situations in addition to the production interruptions. Some alternatives for mitigating the risk of working in ore passes including plugging and ballooning are described. Criteria are included for selecting a method for the safe entry into a given ore pass. Experience in adapting the method of ore pass plugs and some lessons learnt in the process are also discussed.

Jan 1, 2005

By Dmitrievskaya TY, Cheremnykh PA, Kuftinova IV, Yaremenko VN

The comprehensive processing of raw materials and the tendency to waste-free production require the combination of various methods of concentrating mineral resources. Magnetic separation, an ecologically clean method of concentration, is one step in the technological cycle of ore processing, and cleaning and classifying of raw materials. Separators with superconducting magnetic systems cooled by liquid helium are the novel equipment for practical concentration. Recently, high-gradient (HGMS) and open-gradient (OGMS) magnetic separators using the effect of superconductivity have appeared. The separators of the first type are expedient in the head-end of the technological cycle, as they are most efficient for processing of particles 100 ¦m and greater in size. In this case the main task is to obtain pure tailings with a minimum amount of the useful component. This method allows the essential reduction in the cost of the subsequent crushing and grinding, because only the magnetic concentrate is directed to further processing. The separators of the VGMS type are used more efficiently in the final stages of the concentration cycle to condition the end product. The present work is devoted to the theoretical and experimental investigation of the motion of weakly magnetic particles in the working chamber of superconducting separators of the open-gradient magnetic separator (OGMS) and HGMS types. The flat OGMS is equipped by a magnetic system with NbTi racetracks cooled by liquid helium. The chamber is divided into zones by partitions parallel to the plane of the magnetic system. It is shown how, depending on the number of the zones and their depths, the extraction function of the OGMS varies and the transition from the OGMS to the HGMS occurs. The particles 2 mm and less in size are considered. The extraction parameter distribution of the particles was measured for a multicomponent weakly magnetic ore. It was experimentally shown that xD2 is the extraction parameter for the particles in the OGMS on condition that (p-po)D /l8/tl/g

Jan 1, 1993

By J J. McNee and, J Crusius, T F. Pedersen

The use of water covers is a globally-applied method for minimising acid rock drainage (ARD) and metal leaching. Although the subaqueous disposal of potentially acid-generating materials has been shown to effectively limit ARD, under certain scenarios, metal remobilisation can occur at circum-neutral pH. The following paper presents data from four case studies in which metal mobility from submerged mine waste resulted in degradation to water quality in the overlying water cover. Subcentimetre resolution profiling of dissolved constituents across the tailings-water interface (dialysis arrays), in conjunction with mineralogical information, were used to elucidate the controls governing metal mobility. The data illustrate four pathways of metal remobilisation, including: the release of zinc via the oxidative remineralisation of metal-rich organics at the tailings-water interface; enhanced remobilisation of arsenic as a result of anthropogenic eutrophication; the release of copper resulting from the pH-driven dissolution of treatment sludges; and the release of radium from uranium mill tailings due to the dissolution of radiobarite [(Ra,Ba)SO4] by sulfate-reducing bacteria. The results highlight the conclusion that the chemical stability of submerged tailings reflects both: the solid-phase characteristics of the tailings material; and the physical, chemical and biological characteristics of the depositional environment. In particular, the data illustrate that rigorous characterisation of both the waste solids and receiving environment must be performed in order to assess their compatibility. The results have relevance to the management of tailings repositories including constructed impoundments, pit lakes and natural lakes.

Jan 1, 2003