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By W J. Rankin, D R. Swinbourne

There are large tonnages of low-grade manganese ores in India fromwhich it is uneconomic to produce ferroalloys by conventionalsubmerged arc furnace smelting. A possible way to utilise these ores is to smelt them with carbon to produce pig iron and a manganese-rich slag, then to metallothermically reduce the molten slag to silicomanganese. Thermodynamic modelling of the metallothermic reduction stage using aluminium, silicon or aluminium-silicon alloy as the reductant at 1450¦C showed that an acceptable grade of silicomanganese could be produced. Manganese recoveries were predicted to be about 80 per cent. Heat balances indicated that silicothermic reduction may not produce enough heat to maintain reaction temperature. Small-scale laboratory experiments showed that the manganese grade of the alloys, and the manganese recoveries, were close to those predicted, but those for silicon were muchlower. Aluminothermic reduction produced the highest grade manganesealloy. The slag-metal equilibrium involving manganese, silicon and their oxides was investigated and it was found that equilibrium was not attained in any of the experiments, due probably to the very low rate of reactions involving silicon. This could be used to advantage in practice to achieve higher manganese levels in the alloys.

Jan 1, 1998

Can mining promote sustainable development? What is sustainable development? Is sustainable development good for corporate sustainability? Does it work in practice? If so, is it good for business? This paper does not seek to provide definitive answers to these issues. Rather, it is presented in the interests of sharing information and contributing to the pool of collective experience. The discussion will draw on the experience of Placer Dome in Papua New Guinea (PNG). Sustainable development means development that is maintained at a steady level without exhausting natural resources or causing ecological disturbance. The term æsustainable developmentÆ is often linked to the concept of ecological equilibrium, development that is self-replenishing. While its essential meaning remains the same, in practice, and for todayÆs complex and industrial world, different people will interpret sustainable development in different ways. Given the dynamics of development and the competing social, political and economic interests, sustainable development must be seen from a much broader perspective. This is the point that this paper will attempt to make. Mining, an activity that uses non-renewable resources, can promote sustainable development. The 1987 Brundtland Report (also known as the Report of the World Commission on Environment and Development), defines sustainable development in a broader manner - as development that meets the needs of the present world without compromising the ability of future generations to meet their own needs (Elkington, 1997). This definition calls for inter-generational equity in the development and use of resources by many organisations, including multinational corporations. Corporate sustainability, on the other hand, is about developing strategies that guide a corporation to stay alive and, more importantly, to stay ahead of its competitors. It is basically about survival in a competitive social and commercial environment. In a corporate world, profitability is survival. In this context, corporate profitability, the main ingredient of corporate sustainability, is important for sustainable development. Without profits, corporations will find it difficult to practice sustainable development or indeed any development. Sustainable development can integrate mining activities with the rest of the community, add value and, in the long-term, profits to the bottom-line. Ultimately, sustainability will force corporations to adopt strategies based on a longer time scale to survive. In the mining sector, corporate sustainability depends on a close relationship with all stakeholders, particularly landowners for whom sustainable development is critically important. Increasingly, there is an acceptance of the view that success is not achieved simply through competition in price, cost and technology but, more importantly, through creating social infrastructure which support community ethics, norms and values essential for trust and partnership. Needless to say, mining companies that engage in appropriate community-based development in support of inter-generational justice recognise the true value of sustainability. This is sometimes called the æhuman sustainability approachÆ which underlines the critical significance of trust in relationships with stakeholders and continuous improvement of corporate capabilities directed towards the future (Dunphy and Griffiths, 1998). In the long-term, such development will enhance corporate public image and acceptability. In practice, both concepts can be built on the principles of economic viability, environmental quality and social justice -what, in todayÆs parlance, is increasingly becoming known as the ætriple-bottom-lineÆ approach to business (Elkington, 1997). Underpinning this approach is a process of continuing dialogue and co-operation between governments, non-government organisations (NGOs) and business.

Jan 1, 1999

The Horn Island gold and mineral field produced 194 kilograms of gold in the 4 years subsequent to its discovery in 1894, from an area of shallow workings 1.5 kilometres x 0.5 kilometres. Gold deposits in the adjacent Prince of Wales, Hammond and Possession Islands also drew attention at that time.These islands form part of a Carboniferous sequence of ignimbrites (Torres Strait Volcanics) intruded by the Badu Granite and minor volcanics within the Cape York-Oriomo Ridge. Gold is associated with the epithermal stages of igneous activity. Recent exploration has defined sub-horizontal zones of disseminated gold mineralisation in the sub-surface, as well as reserves in the outcropping sub-vertical structures mined in the past. Released estimates of 170,00 tonnes proven ore and 550,000 probable ore at 4 grams per tonne gold, have been established.Gold is mostly contained in quartz vein stockworks and hydrothermal breccias within the intensely propylitised medium grained granites which form the local host rocks within the coarse grained Badu Granite. Associated vein minerals are sulphides (primarily of lead, zinc and iron) and calcite. Various intrusions of porphyry, aplite and granodiorite occur through the prospect area.

Jan 1, 1986

Changes in mining technology have led to an increase in the number of underground sulfide dust explosions reported in Australian and overseas mines. Samples collected at the Elura mine consisting primarily of pyrite, pyrrhotite, arsenopyrite, sphalerite and galena, were tested in 8 litre explosion chamber. The dusts were found to be capable of producing dangerous dust explosions with maximum explosion pressures of 440 kPa and rates of pressure rise of 5200 kPa/s. The hazards of a sulfide dust explosion are associated with the pressure wave and flame front of the explosion and the toxic gases remaining after the explosion.

Jan 1, 1984

By M Fitzgerald

Fimiston Open Pit is operated by Kalgoorlie Consolidated Gold Mines (KCGM) as a joint venture between Barrick Gold and Newmont Mining. Over 110 years of underground mining resulted in the development of nearly 3500 km of underground workings including backfilled and open stopes up to half a million tonnes in size. These voids significantly complicate blasting processes at KCGM, influencing blast movement direction and magnitude. Blast movement monitoring to improve mine reconciliations was identified as an improvement project in the business plan for the geology team in 2008. Following successful trials in 2008 to 2009, blast monitoring and translation of ore blocks were implemented as a permanent grade control program from late 2009 and is now part of the Management Operating System (MOS) of the mine. This paper presents a summary of results from the Blast Movement Monitoring (BMM®) data collected to date. Ore blocks at KCGM are translated primarily using BMM® data. This data is obtained from the BMM® system which measures the movement of a radio transmitter installed in a blast pattern from a preblast position to a post-blast position. The application of the data collected by the BMM® tends to be both mine site and blast specific. At KCGM, an average distance obtained from the BMM® data within a given shot is the primary method used for translation. In the case that BMM® data is unavailable, a theoretical movement vector established from Orica Shotplus with distances gained from the historical BMM® database is used. Data is presented in an ore loss and dilution exercise for a bench undertaken at KCGM to understand the potential effects on reconciliations. Improvements that have flowed from implementing blast monitoring include improved reconciliations when combined with other grade control improvement projects. The increase in liaison between the geology and blast personnel at KCGM has been a significant improvement gained from the implementation of the blast monitoring program. This has allowed a better understanding of blast movement and the effects on ore dilution and ore loss by the mine geology team. In addition, the discussion of blasting tie-in plans between geology and blasting personnel has been improved which leads to more favourable blasting practices that take ore movement into account.

Aug 22, 2011

By A P. Wilkinson

This paper reports on the implementation of the critical control concept to manage material risks in the mining and metals industries. The critical control management (CCM) approach assumes it is better to identify weaknesses in risk controls before an incident happens as opposed to discovering weaknesses from an investigation after an incident occurs. The first is sometimes referred to as active monitoring and the second as reactive monitoring (Health and Safety Executive and Chemical Industries Association, 2006). Both are needed. However, whilst methods for both active and reactive monitoring of risk controls are well established in many high hazard industries, such as oil and gas, petroleum and chemical industries, until the publication in 2015 of the International Council on Mining and Metals (ICMM) guides, (Good Practice Guide and the subsequent Implementation Guide) (ICMM, 2015), there was no specific mining and metals industry guidance on critical control management. This paper reports on progress in implementing the ICMM guidance drawing on two main sources. First, a benchmarking survey of a representative sample of coal and metalliferous mines, both underground and open cut/pit), sponsored jointly by the Queensland Resources Council and the Queensland Commissioner for Resources Safety and Health in the context of a recommendation that the Queensland mining industry adopts high reliability organisation (HRO) principals (Queensland Resources Council and Commissioner for Resources Safety and Health, 2022). Second, it draws on Noetic’s experience of implementing critical control management in mining and other high hazard industries in Australia, Africa, China and North America (Wilkinson, 2018). The paper describes good practices found and where significant improvements can be made, providing specific and actionable examples of both. From this it also identifies how future guidance on this topic could be improved.

Apr 16, 2024

By D H. Lee, J F, J H. Rubinstein

This paper examines the problem of optimising the life-of-mine costs of an underground mine, focussing particularly on the costs associated with the underground development needed to provide access to and haulage from the ore zones. This mine optimisation problem is modelled as a network and a solution technique is outlined. The effectiveness of this solution technique is then demonstrated by applying it to a prototype test example and some actual case studies. Finally, extensions of this technique to other underground mining problems are discussed.

Jan 1, 2000

By Woodhouse M, Andrews D, Drew G

The nickel deposits within the Honeymoon Well project area (26¦ 40'S, 120¦ 25'E), located 45 km south of Wiluna, occur in the northern part of the Agnew-Wiluna belt (Figure 1; Hill et at, 1990). The project area is covered by up to 50 m of transported material which greatly hampers both exploration and an understanding of the bedrock geology. Since 1990 intensive exploration has increased the resource from 10 Mt at one per cent Ni to 134 Mt at 0.76 per cent Ni in five deposits (0.4 per cent Ni cut-off, resources above 300 m depth, December 1994). This includes a massive sulphide resource of 2.5 Mt at 3.4 per cent Ni.

Jan 1, 1996

Wollongong* is Australia's largest single centre of mining and metallurgy. Wollongong's total employment in manufacturing of basic metal products (over 26,500 in 1972/1973) was almost 50 per cent higher than that of Newcastle and double that of any other Australian city. Although the great bulk of this employment was in steelmaking, Wollongong's copper industry was also a significant employer. Wollongong's total employment in mining (4,900 in 1971) was second only to that of Newcastle among Australian mining centres. Although the bulk of Wollongong's mining is of coal, there is also considerable mining of blue metal, sand and clay. In all, over 40 per cent of Wollongong's work force is employed in mining and metallurgy. The great bulk of the other

Jan 1, 1976

We are moving into an era where we experience the consequences of the skills crisis û namely many resource models have been generated by inexperienced people under pressure to deliver high quality resource estimates in unsupported environments, often without technical mentors. These resource models form the basis of our decision to pursue actual mining. This begs the question: how valid are the resource models that form the basis of our mining decisions? This paper presents various model validation tools such as comparison of input and output statistics, swath plots, sectional or bench comparisons between drill holes and models as well as a variety of other approaches. Each model validation tool currently used in industry is examined:how the tool generates results,what assumptions exist,what constitutes a pass/fail in the test, and what interpretations to consider when using the validation tool. Each validation toolÆs suitability and the inherent flaws in the underlying assumptions are also discussed. These are supported with examples of good versus bad validations. Our principles based reporting codes provide flexibility in how models are generated and what approaches and/or parameters are used to generate resource estimates. This flexibility works well when used by experienced practitioners. However, our reporting codes assume a level of experience not always available in the current skills crisis. This paper seeks to provide minimum model validation prerequisites for model acceptance and suitability, regardless of the resource analystÆs experience. As we move forward, our immediate challenge is to ensure our baseline resource models are material, transparent and competent.

Jan 1, 2009

Since the discovery of coal of the Southern coalfield (Illawarra 1797, Burragorang 1806) coal mining has grown progressively to the thriving industry of today. Early shallow escarpment mining required no serious access development, but with extension of mining to further and deeper areas, sinking became necess- ary. Now, with 17 major shafts and 7 decline drifts in current use, new mining activities involve several current sinking and drifting projects, with more in prospect. Conventional sinking and drifting, using blasting and mucking techniques proven in recent years are normally in use, with attempts, recent and current to accelerate advances by boring techniques. With export and to less extent local market unpredictability, it is vital to produce mine establishment times to allow advantage to be taken of market upswings and there is great need for research and improvement of mine access construction as the major aspect of establish- ment.

Jan 1, 1976

By J Folwell, G Phillips, F Gassner

Geomembranes selected for various applications often start with considering target properties developed by industry organisations such as Geosynthetic Research Institute (GRI), and test methods developed by ASTM and other Standards organisations The geomembrane types are typically, initially selected based on manufacturers recommendations and chemical resistance data from the manufacturer or industry knowledge. Geomembranes considered for this project included materials with material properties that exceeded the minimum target values of various test methods. The difficulty is in selecting which parameters are most important for a particular application and also what service life can be expected for the geomembrane under various chemical and environmental exposure conditions. Accelerated aging testing of candidate geomembranes in simulated exposure conditions can be useful to select the preferred geomembrane and predict the service life of the geomembrane under different exposure conditions. The exposure conditions of immersion in acidic tailings liquor, splash zone and freeboard zone were considered for evaporation ponds on a site with significant heat and UV radiation. Candidate geomembranes considered a range of different types of polyethylene liners. The results of the accelerated aging testing have allowed the selection of the geomembrane for the range of exposure conditions and evaluation of the expected service life of the geomembrane.

Jul 1, 2021

By T Sprague, D Pateman

"The Gosowong Gold Project is owned and operated by PT Nusa Halmahera Minerals (PT NHM), an Indonesian company 75 per cent owned by Newcrest. It is located on Halmahera Island, in the North Maluku Province of the Republic of Indonesia, approximately 2450 km north-east of the national capital, Jakarta (Newcrest, 2017).Kencana is one of two underground gold and silver mines at the Gosowong Operation where ground conditions vary from competent to very poor. Development headings occurring in poor rock mass conditions require high capacity ground support including long tendon cable bolts. Manual installation of cable bolts in these development headings has been a time consuming process due to borehole collapse, blockages requiring subsequent re-drilling and a minimum eight hour grout curing time interval. The installation of cable bolts including the setting, plating and tensioning can impact the critical path for development heading advance resulting in development cycle delays.A review was conducted by PT NHM on current industry practices for alternatives to manual cable bolting. PT NHM subsequently approached Minova to assist with the development and trialling of self drilling anchors (SDAs) installed using jumbos with a rapid setting pumpable resin, CARBOTHIXTM. A series of system development trials were conducted and a reliable bolting system was developed utilising the existing jumbo drilling fleet with minimal required modifications.The system developed was a ‘one pass’ bolting process to install and grout SDAs using a two component resin with a remote, mechanised system. Improvements achieved from the system include: eliminating hole closure issues and more immediate support in poor rock mass effectively reducing personnel exposure to poor ground conditions by removing the requirement to access the drive backs reducing grout set time with full installation times for 6 m SDAs averaging 25 min.The resin grouting system has now been successfully implemented to effectively manage areas of poor ground conditions and to accelerate advance rates in high priority headings.CITATION:Pateman, D and Sprague, T, 2017. Development and implementation of a long tendon bolting system utilising resin grouting technology, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 16, 2017

By R G. Richards

Although most New Zealand coals are low in ash, there are situations where high ash coals could be won. Not all high ash coals can be upgraded by physical means, since the ash is either inherent in the coal or bound in such a way to make its physical removal either impractical or uneconomic. Nevertheless, the authors believe, the situations where high amounts of ash can be economically removed by physical means to make a saleable product are considerable.

Jan 1, 1979

By D J. Brake

Most mine ventilation engineers are involved in ventilation planning and design in some capacity. Ventilation modelling software used by a competent experienced ventilation engineer is extremely useful in developing good ventilation designs by allowing assessment of a wide range of potential options. Unfortunately, ventilation modelling undertaken by persons who do not have sufficient experience or knowledge usually results in a façade that covers up a fundamentally unsatisfactory design. Ventilation models are produced for a wide variety of purposes including: fault-finding of a problem area in a mine and options analysis for resolution of such problems; a complete review or optimisation exercise of an entire mine’s ventilation system; or a much longer life-of-mine type of study. Models can be intended as the basis for studies with diverse purposes such as primary shaft or airway sizing, primary fan specification, examining re-entry times after blasting, resolving leakage or recirculation, or investigating the impact of fires or underground climate or cooling requirements. The concepts of ‘materiality’ and ‘fitness for purpose’ are essential to developing or using a ventilation model and serious mistakes have been made in wrongly using a ventilation model for purposes for which it was never intended, often because it is simply the most recent model on the mine site. Mistakes at this level often translate into faulty ventilation strategies and inefficient or ineffective use of scarce capital for ventilation projects. Validating a ventilation model is a time-consuming and expensive process and not every model must (or even should) be fully validated to meet the objectives at that time. This paper discusses the application of quality assurance in ventilation planning with particular respect to the ‘basis of design’ (BOD) as well as the standards for validating a ventilation model. It also provides a recommended way of dealing with non-conformances in measured versus modelled values of critical parameters in the model.CITATION:Brake, D J, 2015. Quality assurance standards for mine ventilation models and ventilation planning, in Proceedings The Australian Mine Ventilation Conference, pp 221–228 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

After a short theoretical comparison of various typical large bell tops with the bell-less top for segregation and other ,ffects on the material flowing through the equipment proper, a comparative analysis between classical and the new burdening in the furnace is given, showing the theoretical effects of distribution and segregation on the horizontal pressure variations, temperature values and gas composition in the stack. Then some typical theoretical charging patterns of the bell-less top for wall and centre temperature adjusting, pressure drop corrections, dissymmetric local action for blow-in and scaffolding are described. Finally the available practical results on furnaces equipped with the bell-less top are compared with the theoretical statements made before and conclusions indicate that the new approach to burdening blast furnaces is a real improvement.

Jan 1, 1975

By Wharton C. L

This paper describes a new computer program which can significantly increase the Net Present Value of either an open cut or underground mine by optimising the cut-offs used during the operating life of the mine. It was developed over a period of about three years by Whittle Programming Pty Ltd of Melbourne, Australia. Several authors have contributed to the theory behind this work, but the ideas were further developed, consolidated, and clearly explained by Lane (1988). It was this book that triggered the development of the new program. The paper starts with an explanation of the theory behind this type of optimisation, and then goes on to describe the computer methods used to optimise the different parts of the problem.

Jan 1, 1995

By V Lawson

Vale’s Sudbury Clarabelle Mill processes Cu/Ni ores from a number of mines in the Sudbury basin in Ontario, Canada. Bulk sulphide flotation produces a copper-nickel concentrate with pyrrhotite as the major diluent. After successful commissioning of the Voisey’s Bay Cu/Ni Mill (VBN) in Labrador, a miniplant campaign on Clarabelle ore with the VBN flow sheet produced a significant recovery improvement over current performance. In 2001, the Mill Redesign Project moved grinding energy into rock/sulphide and pentlandite/pyrrhotite separation and in 2006 Cu/Ni separation was re-introduced to Clarabelle Mill to produce a saleable Cu concentrate. The projects were a great success. What remained was to simplify the Clarabelle flow sheet by introducing the missing components found in the VBN flow sheet. This project known as CORe has evolved through many stages including the mining boom and surviving the 2008 economic downturn and it is scheduled for completion in mid 2013. This paper outlines some of the challenges faced in this major brownfields project – organizational, technical, financial and operational.

Aug 8, 2011

By P Ridley

EnergyAustralia’s Sydney Central Business District (CBD) cable tunnel network will form a loop 6.2 km in length. The 3.2 km long, 3.5 m, diameter city east cable tunnel (CECT) currently in design, will complete the loop in 2014. This paper discusses the ventilation design of the CECT, considering operation for four functions:1. normal (unmanned),2. access (manned),3. purge, and4. emergency fire modes.The dominant design criterion which determines the required ventilation capacity for CECT is the specification of an upper air temperature limits of 35°C (dry bulb) and 24°C (wet bulb) for manned access, during all ambient weather conditions and cable heating loads. Simplistic static heat transfer analyses do not yield a sufficiently accurate calculation of tunnel air temperature and humidity to provide a safe and yet economical design. The primary refinement in the analysis discussed in this paper is associated with modelling of the system’s dynamic behaviour.Our means of analysis is through a thermo-fluid-dynamic simulation of the interactions between the diurnally and seasonally varying loads (cable heat generation, ambient air conditions and groundwater inflow), tunnel airflow and the resulting tunnel air temperature and humidity. These simulations are validated using experimental data from the existing city south and city west cable tunnels.Fire life safety scenarios are also analysed and discussed in association with the ventilation design. Ventilation strategies are developed for dealing with such emergency fire situations.The understanding and insight provided by the work offers the ability to optimise ventilation plant provisions in future cable tunnels, particularly long and high energy density tunnels.

Mar 8, 2011

By M Flis

The Razorback Iron Ore Project is a high tonnage, low-grade magnetite deposit that defines a new iron ore district in South Australia. Known since the 1960s, the deposit has come into its own as the iron hungry world demands not only larger tonnages, but higher grade and cleaner magnetite concentrate ores that counterbalance the increasingly dirty haematite ores that are coming into production.Razorback is hosted by the Neoproterozoic Braemar Iron Formation, a tillitic unit that is part of the Adelaidean Geosyncline sedimentary sequence. At Razorback, this formation forms the southern limb of the Pualco Syncline, dipping at 42° to the north and outcropping along a prominent ridge. The formation consists of a series of alternating bedded tillitic and interbedded magnetite units that represent cycles of glacial advances and retreats. Seven cycles, resulting in seven stratigraphic members, are recognised. Members B, D, and G are the thickest, at 30 - 70 m each, and are the target of current investigations. While the bedded magnetite has the highest iron content, typically 35 per cent Fe, the tillitic unit, at typically 26 per cent Fe, has similar iron content in the ground mass but is diluted by the inclusion of iron-poor granite and metasedimentary dropstones. The mineralisation forms a simple dipping tabular body with only minor faulting, folding and intrusives. Grades, thickness, dip, and outcropping geometry remain very consistent over kilometres of strike, presenting an excellent mining proposition.Razorback differentiates itself from other Australian magnetite projects in a number of important ways. It is not a banded iron formation (BIF); it will have low crushing and grinding costs; and it is located in an infrastructure-rich area close to open-access, high capacity rail, to a selection of ports and to gas, electricity, labour and engineering services. Royal Resources has announced an Inferred resource of 277 Mt @ 25.9 per cent Fe. The company is targeting a resource of 500 - 1000 Mt to support a 10 Mt per year concentrate production. Davis Tube Recovery work shows that the ore is capable of producing a concentrate of over 68 per cent Fe with very low deleterious elements. Metallurgical testing confi rms the ore is soft, and with near-zero initial stripping ratio the project will have a low opex. With access to existing critical infrastructure, capex will also be low, ensuring Razorback will be a highly competitive iron producer in this emergent mining district.

Jul 11, 2011