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By E Selvapandian, R Barr

Arrium (previously OneSteel) initiated a desktop study into the performance of its hematite ore beneficiation plant in early 2010. The beneficiation plant utilises jig concentrators and spirals to upgrade low-grade hematite recovered during mining at the Iron Duke (ID) mine site located 60 km south-west of Whyalla. The study, conducted in conjunction with Mineral Technologies, identified a number of opportunities for improvement, which were validated by a series of sampling campaigns and a pilot plant trial. One of the major recommendations was to upgrade the ultra-fines processing circuit from a single-stage spiral circuit to a three-stage circuit. The upgrade of the ultra-fines circuit was estimated to provide a significant increase in fines production and grade.In order to capitalise on the strong iron price at the time of the project, Arrium decided to utilise a fast-tracked approach to design, construct and commission the processing equipment required to achieve the improvements identified. This decision introduced the risk of missing critical steps in the project development process, which could have potentially resulted in major issues in latter stages of the project. In addition to the challenges introduced due to the expedited time line for project completion, this project presented unique challenges due to its brownfield nature. One such challenge faced was the integration of the new equipment and control system software.Furthermore, the importance of the ID ore beneficiation plant (OBP) contribution to the companyÆs export commitments meant the upgrade work had to occur while minimising disruption to normal operation. This decision presented a set of new challenges to an already complex project. One such challenge was the need to build and commission the new spiral circuit in isolation from the operating plant.The aim of this paper will be to highlight some of the challenges faced in a complex brownfield project such as the ID OBP upgrade and discuss how they were managed to enable the successful commissioning of the process in early 2012.CITATION:Selvapandian E and Barr, R, 2013. Managing challenges faced in the brownfield commissioning of an ultra-fine hematite processing circuit at ArriumÆs Iron Duke ore beneficiation plant, in Proceedings Iron Ore 2013 , pp 533-538 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Consents Required for Overseas Persons Overseas Investment Regulations 1974 Foreign investment proposals must be reviewed by the Overseas Investment Commission to ensure that these are in accord with national interests. Consent must be obtained from the Commission for: 1. New investment proposals which include: a. An overseas person acquiring 25 per cent or more of any class of share in a company. b. A New Zealand company issuing shares to an overseas person where this will result in that person owning 25 per cent or more of the company. c. An overseas person acquiring business assets for consideration in excess of $100 000. d. An overseas person commencing business in New Zealand. 2. Borrowing in New Zealand: An overseas person must obtain consent to raise funds in excess of $300 000 in New Zealand. 3. Borrowing Overseas: New Zealand incorporated companies must obtain consent to borrow overseas. Current policy is borrowing will be approved where the loan is for a specified fixed term of one year or more.

Jan 1, 1982

By L A. Martinez Tipe, J McKibben, S Barry

"Metal prices are central to a mineral investment decision and have a profound impact on the financial performance of companies in the mining industry. At its most basic level, metal prices are influenced by the disequilibrium between international metal volume supply and demand. That is, the commodity price is a regulator that equates international metal supply and demand where inventories act as a buffer between the emergence of this disequilibrium and its dissolution through a price change.From this viewpoint, mining companies are required to forecast metal and bulk commodity prices when evaluating minerals projects through discounted cash flow (DCF) analysis. While supply-demand models are instructive, many companies use historical prices, spot prices, futures/forward pricing and consensus opinion (or a combination of all of these) to develop price forecasts.This paper discusses the definition, fundamentals and differences between futures/forward and consensus pricing and the appropriateness of each in a DCF model for mine project economic evaluation.Our results demonstrate that great care is required when using either futures/forward or consensus pricing and that the decision to use one rather than the other requires consideration of other important elements in the DCF model (ie the risk-adjusted discount rate).CITATION:Martinez Tipe, L A, McKibben, J and Barry, S, 2016. Metal prices and the differences between forward and consensus pricing – which one is better for use in a discounted cash flow model?, in Proceedings Project Evaluation 2016, pp 149–158 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By A Webster, T Murphy

Block cave mining, in its broadest sense, has transitioned from an orebody/rock mass determined method of extraction, to a low-cost and high production mining method that may be applied to any large ore deposit. This inherently means that caving is now required in more complex rock mass conditions where assistive damage, through preconditioning, may be necessary. This requires comprehensive understanding of the geology, and its interwoven relationship with geotechnical parameters, and is made more challenging due to limited exposure in block cave mines. Limited mine development throughout the cave volume equates to a heavy reliance on drilling data in terms of observations, modelling of the mine geology, and collection of geotechnical data. This translates as increased uncertainty of geological and geotechnical models and has potential to impact significantly on the ability to make informed decisions in the design and operation of the cave mine.Modelling of cave propagation behaviour requires a complex, coupled system of draw of material, flow of material through the cave stocks, and propagation of the cave-back assisted by autogenic stress-related breakage of the rock mass, manifested as seismicity. The role of geological features in the process of cave propagation is not well understood and requires evaluation on a mine-specific basis, given the diversity of geological controls/settings of ore deposits and local variability of stress fields.Seismic monitoring systems can elucidate key geological features and domains, as heterogeneous seismogenic activity is observed ahead of the advancing cave-back. The observations made from analysis of seismic monitoring data may have potential to be used as a validation tool for numerical modelling of predicted cave behaviour in similar geological settings (eg next lift/panel).Understanding of the geological structure, at all scales, is critical to optimise the design and operating decisions made in a block cave operation. At present, intermediate-scale structure, anisotropy, mineralogy and model uncertainty may be neglected or under-represented despite their likely significant role in the mechanisms of cave propagation.Insights from an analysis of the Ridgeway Deeps block cave mine are discussed in this paper.CITATION:Murphy, T, Webster, A and Chitombo, G, 2016. Beyond rock mass characterisation – the impact of geology on block cave mining, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 861–872 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By K G. Harding, E L. Haggard, C M. Sheridan

Mining is a water intensive sector, contributing to declining water resource quality around the world. Improvements to current mine water management practices can help reduce the amount of water utilised by the mining sector and the impact on water resources. Creating a water account can help companies understand water use in their operations and identify areas where water reduction is possible. Water accounting methods include the Water Footprint Network method and the WaterMiner tool.The Water Footprint Network method is used to determine the amount of direct and indirect water used by an organisation either in a process or to manufacture a product. The total water footprint is divided into the blue, green and grey water footprints. Blue water is the amount of water abstracted from surface and ground water resources. Green water is the amount of rain water utilised. Grey water is the amount of freshwater required to assimilate the waste stream to the natural resource and still conform to ambient water quality standards.The WaterMiner tool is a program available via the internet, which can be used to model water use of mineral processing sites. The program reports the amount of raw, worked and treated water used by the process and recommends flows that can be added to reduce the amount of fresh water required by the process.To gain information on mine water management practices in South Africa, a water account for a platinum mine was developed using the Water Footprint Network method and WaterMiner tool. Based on the results, suggestions to reduce the amount of fresh water utilised are made.CITATION:Haggard, E L, Sheridan, C M and Harding, K G, 2013. Water footprint for a South African platinum mine, in Proceedings Water in Mining 2013 , pp 15-20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

Technologies are receiving a lot of 'press' - and rightly so; as they are seen as the means for achieving quantum leaps in productivity and cost reductions. A point of concern for Caterpillar is that we do not believe there is enough understanding of the infrastructure needed to support some of the future technologies, as well there is not enough utilisation of the current systems.

Jan 1, 1997

By Higgins RJ

Environmental investigations have been undertaken by Ok Tedi Mining Limited (OTML) since 1981 when the Ok Tedi Environmental Study was commenced. Environmental monit- oring and management programmes were implemented in 1983. The programmes included water quality monitoring, river flow and sediment monitoring, surveillance of aquatic biological communities and a health and nutrition survey of the local people. These original programmes have continued, and additional programmes of work have been developed and revised to reflect changing operations and the need to focus investigations on specific areas and issues of concern. In April 1990, following the establishment by the Government of Papua New Guinea (PNG) of environmental management criteria for the Fly River system, compliance monitoring programs were introduced. Details of the compliance and additional monitoring programmes undertaken by OTML throughout the Ok Tedi and Fly catchments, including programmes of investigation in the Fly River estuary, Gulf of Papua and Torres Strait, are presented.

Jan 1, 1991

Flotation Performance Improvement by Air Recovery Optimisation on Roughers and Scavengers

Sep 13, 2010

By D Kepert, M Absalom, N Nitschke, C Fowers

The discovery of the Nyidinghu Iron Ore Deposit totalling 2.46 Bt of resource continues FortescueÆs highly successful exploration record of discovering multi-billion tonne deposits under cover with little to no surface expression. Since inception in 2003 Fortescue have discovered and delineated the Christmas Creek and Cloudbreak deposits in the Chichester Range totalling 3.38 Bt and 3.25 Bt in the Solomon region. Together with other deposits Fortescues resource portfolio now approximates 10 Bt of hematite - goethite mineralisation.The Nyidinghu deposit is situated on the southern margin of the Fortescue Valley, 35 km south of FortescueÆs Cloudbreak mining operations on the north margin of the valley. Nyidinghu comprises approximately 70 per cent BID martite - goethite mineralisation hosted by the Brockman Iron Formation and 30 per cent CID beneath alluvial outwash of the Weeli Wolli Creek in to the Fortescue Valley. Minor DID mineralisation occurs at the deposit margins.BID mineralisation is strongly controlled by the pre-existing NE/SW trending Weeli Wolli Fault system and bounded to the north by the Poonda Fault. Both fault systems are interpreted to have had a long and complex history commencing pre Ophthalmian Orogeny (ca 2.2 Ga) and remaining intermittently active through the Proterozoic.CID at Nyidinghu is the downstream continuation of the combined Weeli Wolli/Marillana CID palaeochannel system being mined by Rio Tinto and BHP Billiton at Yandicoogina and Yandi, respectively.Exploration commenced in August 2010 with the inaugural resource announcement of 1 Bt being made just six months later. To date over 1700 RC and 85 diamond core holes have been drilled forming the basis for the resource of 2.46 Bt and ongoing feasibility studies. Current exploration activities continue to delineate new mineralisation at Nyidinghu with an ultimate target tonnage of 3 Bt.CITATION:Fowers, C, Kepert, D, Absalom, M and Nitschke, N, 2013. Discovery, geology and structural setting of the Nyidinghu iron ore deposit, Hamersley Province, Western Australia, in Proceedings Iron Ore 2013 , pp 81-90 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Van Dusen M

The involvement of concerned parties in all aspects of the Lihir Project from an early stage has promoted good relations between all groups. Activities involving landowners, the Lihir community, the New Ireland Provincial Government (NIPG) and the prospective developer include the Lihir Liaison Committee, Lihir Working Group, Environmental Planning Committee, Provincial Mining Task Force and the Lihir Mining Area Landowners Association (LMALA). With modifications, the Lihir Liaison model may be of use in promoting good relationships among parties in other mineral developments.

Jan 1, 1991

The Department of Mineral Resources is the lead agency in mine site environment management and control inNew South Wales. The Department introduced a Mining, Rehabilitation and Environmental Management Plan (MREMP) process several years ago in order to integrate the activities of other government agencies who may have a material interest at the mine site. The MREMP process has resulted in a spirit of trust and co-operation between agencies and between agencies and mining companies. The spirit of co-operation has been reflected in greater public confidence that mining is environmentally responsible.  

Jan 1, 1995

By Y Yang, J Skrypniuk

The Jinfeng mine is Sino Gold's flagship project and is the second largest gold mine in China. Sino Gold Limited (SGL) holds 82 per cent equity in the Sino-Foreign joint venture Sino Guizhou Jinfeng Mining Limited (SGJML) with a Chinese partner. Jinfeng is located in a relatively remote site in southwestern Guizhou province. The orebody is considered to be the largest known Carlin type deposit in China. Jinfeng Plant has the world's third largest BIOX« bacterial oxidation facilities (790 t/d), treating highly refractory concentrate generated from crushing, semi-autogenous grinding (SAG) and ball milling and bulk sulfide flotation operations. The Jinfeng Plant construction started in February 2005, commissioning was completed in April 2007, and commercial gold production was achieved in September 2007. This paper describes the successful operations of Jinfeng Plant over the last two years. The key events of the project development are described, from the project background and process design, through to the commissioning and achieving design mill throughput of 3600 t/d resulting 180 000 ounces of gold per year. Process aspects of the BIOX« and carbon-in-leach (CIL) operations over the last two years are discussed which illustrate a very high BIOX« oxidation rate (more that 97 per cent) and excellent CIL recovery (more than 96 per cent). The management of the Jinfeng plant CIL tailings detoxification and filtration is described, and Jinfeng has became the first BIOX« processing plant to have achieved dry stacking of detoxified and pressure filtered CIL tailings. Current efforts to recover cyanide from CIL detoxified solution and the achievement of a zero discharge site water balance are also introduced. Many improvement projects have been made over the last two years which have culminated in a 15 per cent increase in mill throughput over the design and BIOX« CIL recovery increasing from 92.5 per cent to 96 per cent. Significant operating cost reductions from lowered of acid, lime and cyanide usage through process modifications and technical innovations are discussed.

Jan 1, 2009

By B Nielsen, H Lehto, B Musuku

"The demand for fine and ultra-fine grinding associated with the processing of more challenging, finer grained orebodies and the global driver of minimising energy consumption has been an increased focus in our industry. Outotec’s stirred milling technology, the high intensity grinding mill (HIGmill™), was launched in 2012 in response to this industry need. First Quantum Minerals Ltd selected HIGmill™ technology for its Kevitsa mine in Northern Finland. The 700 kW mill is grinding copper rougher concentrate to improve copper/nickel separation and copper recovery. Selection of the HIGmill™ followed mineralogy analysis and laboratory and pilot testing for HIG milling in parallel with flotation tests to determine optimum grind size and energy input.The paper discusses the challenges and successes of the test work, manufacture, installation, commissioning and subsequent operation of the mill. Grinding performance is presented and a comparison between predicted and operating energy efficiency is made. In addition, the various steps to optimise wear rate and minimise maintenance and downtime are made, with particular reference to internal geometry of the mill.Citation:Nielsen, B, Lehto, H and Musuku, B, 2016. Design, Installation, Commissioning and Operation of Fine Grinding Technology at the Kevitsa Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 59–66 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

Last evening, in Auckland, I heard the Chairman of Heinz US, Dr Tony O'Reilly (who, in addition to Heinz's ownership of our largest food processor, also has substantial personal investments in this country), advocate New Zealand as a 'regional corporate capital'.   Why would someone like Dr O'Reilly hold that view? No doubt, as one of Ireland's great rugby players of the 50s and 60s, he admires at least one thing that we do very well (confirmed again in Dublin over the past weekend). But that's not sufficient to support such a view.   He cited many reasons for preferring New Zealand over, say, Sydney, Australia, calling this 'the most rational in which to locate [an] international headquarters', including û +         we have no capital gains tax; +         a more 'pro-business environment'; +         a 'first class' legal and banking system; and +         a 'simple political system'.   I can find no better 'text for today's address.

Jan 1, 1997

Using Dynamic Simulation Throughout a Process Plant's Life Cycle

Sep 13, 2010

By K Williams, A Lavrinec, V Gurung, D Ilic

The moisture content of iron ore during handling can range from the dust extinction moisture at the point of arrival at the port to the transportable moisture limit at the point of loading ships for maritime transport. Moisture content and ore composition, specifically fines content, have a large influence on ore flowability. Typically, elevated moisture can result in bottlenecks, downtime and lost productivity due to build-up, conveyor carry-back and blockages, increasing maintenance costs. On the other hand, low moisture can result in increased dust emissions influencing the environmental footprint and product losses. Managing the use of water across the supply chain is therefore critical for service life of equipment, productivity, but also has environmental and social impacts, affecting the social license to operate. Previously, experiments have shown that oscillations induced in iron ore during handling and transport can result in movement of moisture through the ore. This kind of moisture migration depends on the nature of these oscillations, such as the undulation of idlers during conveying, the inherent ore properties and the initial moisture content. Moisture has been observed to move either upwards and/or towards the bottom of the burden. These effects can be exploited to remove excess water from the ore influencing handleability and operation, however, the actual mechanisms of moisture migration are currently poorly understood. The study presented herein involves the use of simulation to examine moisture and ore interactions. Simulations using discrete element method (DEM) and coupled with smoothed particle hydrodynamics (SPH) are implemented to investigate the behaviour of moisture in wet ore in the presence of oscillation. This is conducted at a fundamental level first using glass beads and water which is then compared to iron ore at high moisture content. The results of the modelling are discussed in view of experiments conducted.

Sep 18, 2023

By D Will

RedrossThe Redross orebody averages 1 m wide, has a strike of 50 - 350 m, dips at 55° and has a basalt footwall and an ultramafic hanging wall. The most successful and innovative aspects of mining Redross were:•ore development innovations, 90 per cent of development was split fired with a shanty back profile to enable larger and more productive equipment to be used and resulted in higher development grades, improved project payback time and improved ore recovery;•hand held stoping using a multiple level, bottom up ‘V’ shaped hand held stoping method that allowed mining on multiple levels with hand held productivities between 50 and 90 tonnes per shift;•the use of 1 m cement pillars and 7 m high crown pillars were used to create multiple mining areas that enabled high overall production rates from hand held mining this orebody; and•the use of vertical cement pillars to enable hand held mining of adjacent stopes without leaving ore pillars.MarinersThe Mariners orebody averages 3 m wide, has a strike length of 50 - 250 m and dips at 50° with a basalt footwall and poor ultramafic hanging wall. The most successful innovative ideas of re-opening Mariners were:•Dewatering the existing mine workings utilising ‘oilfield’ technology by installing a long submersible pump in on existing pump rising main. This enabled the mine to be dewatered at rates up to 100l/ sec and helped overcome the 45 to 55 L/s inflows.•Overcoming the technical problems associated with Mining N07 ore blocks which had severely deteriorated from being underwater for five years by using reverse firing techniques to improve extraction rates and reduce dilution.•Mass firing a large mining block in the N08 with minimal void space because of deteriorating ground conditions.•Use of a longhole version of the Redross hand held mining method to achieve 100 per cent extraction of the N09 higher grade lenses.

Mar 21, 2011

A process was developed to produce electrolytic manganese dioxide, suitable for use in high quality dry cells, from Risdon anode mud. ImpurItIes present In the anode mud were removed prior to the electrolysis which was performed from a manganese sulphate bath using the following conditions.Temp. 95°CH2S04 50-55 g/l.Mn2+ 55-60 g/l.Anode c.d. 10·0 A/sq. ft.Operation under these conditions yielded current efficiency and power consumption figures of 95 per cent and 0·8 kWh/lb respectively. The product conformed to battery manufacturers' specifications as regards physical and chemical properties and performed satisfactorily in a battery testing programme.

Jan 1, 1968

Pyrite Bioleaching and Slag Neutralisation - Two Treatments in a Single Process for Recovering Valuable Metals from Both Materials Very often the production of copper sulfide concentrate yields pyrite concentrate as a by-product. This is the case at the Knre mine in northern Turkey. This kind of concentrate may contain low grades of valuable non-ferrous metals. Bioleaching of such pyrite concentrates is a processing technique to solubilise metals like copper, zinc or cobalt in a sulfuric acid pregnant solution. The pyrometallurgical processing of copper sulfide concentrate produces slag that still contains valuable metals in varying concentrations. Slag is used in many ways: as aggregates, ballast, pavement material, in cement production and glass making. Due to its relatively alkaline nature, it can also be used to neutralise acidic solutions. A preliminary study of the bioleaching of the pyrite concentrate (Co 0.28 per cent, Cu 0.56 per cent and sulfur as sulfide 42.6 per cent) produced at Knre has been undertaken with the assessment of the neutralisation of the acidic bioleach solution by using old slag (Co 0.29 per cent, Cu 1.70 per cent and sulfur as sulfide 0.89 per cent) stockpiled on the site. The main conclusions of the study were as follows: Knre pyrite was amenable to bioleaching at 40¦C. Cobalt solubilisation directly related to pyrite degradation reached a maximum yield above 90 per cent. Final copper recovery was limited to approximately 66 per cent not directly related to bacterial growth and pyrite oxidation. Slag could be used as a substitute for limestone as a neutralising agent in the bioleaching tanks. Cobalt and copper could be recovered from pyrite concentrate and slag simultaneously from both materials. A pre-feasibility study is underway to carry out a preliminary cost estimate of an installation for cobalt and copper production from these two materials processed in a single operation.

Sep 13, 2010

By T Mattiske

The Fimiston Open Pit (commonly referred to as the æSuper PitÆ) is a part of the Kalgoorlie Consolidated Gold Mines Pty Ltd (KCGM) operation in Kalgoorlie-Boulder. KCGM manages the Fimiston Open Pit, the Mt Charlotte underground mine, the Fimiston Mill and the Gidji Roaster for its Joint Venture Owners, Newmont and Barrick Australia. KCGM produces up to 850 000 ounces of gold per year. The KCGM operations are located on the historical Golden Mile on the outskirts of the City of Kalgoorlie-Boulder, about 600 kilometres east of Perth Western Australia. This traditionally underground mining centre has been worked since 1893, yielding in excess of 50 Moz of gold from ore with an average head grade of 10 g/t. This represents approximately ten per cent of the gold produced in Australia and one per cent of the gold produced in the world. The Fimiston Open Pit is essentially an aggregation of what were known as the Judd, South, Paringa, Croesus/Eclipse, Central, Brownhill, Drysdale, Morrison, North and Horseshoe pits into one continuous large-scale operation. The old Fimiston Underground Operations (included the Main, Croesus, Chaffers, Lake View, and Perseverance shafts) were also located within the area of the Fimiston Open Pit. The underground operations closed in 1992 due to high mining costs.

Jan 1, 2002