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By D Thomas

Geochemical data related to AMD for the West Coast and Southland regions have been collated into a relational database and GIS system. The types of information include; rock geochemical data, water chemistry data and aquatic macro-invertebrate abundance data. This information will be combined with eco-toxicology experiments to determine impact thresholds on aquatic ecosystems. Ultimately these datasets will be combined with remediation investigations to produce a Framework to assist decision making related to mine planning, consent and compliance.   Current geochemical research examines the controls on As concentrations downstream of gold mining areas and the variability of AMD from Brunner Coal Measure rocks. Assessment of factors that control the chemistry of Brunner Coal Measure AMD such as mine type, hydrogeology, geology, geochemistry and climate is in progress. Minerals that control the concentration of aluminium downstream of AMD point sources include alunite, jurbanite and various forms of Al(OH)3.

Jan 1, 2005

The gold salting fraud at Busang on the island of Kalimantan, Indonesia was exposed in early 1997 and resulted from the independent drilling, sampling and assaying of PT Freeport Indonesia which reported assays from the South East Zone with negligible concentrations of gold. Since then, a number of legal actions directed at former Bre-X directors, consulting firms and financial or broking institutions are at various stages and are based on numerous allegations surrounding the supposed existence of obvious and numerous warning signs or æred flagsÆ. These include: the absence of references to visible gold in the drill logs; the alluvial nature of the gold grains; the high gravity recoveries; the invalid comparison with Kelian; the absence of outside scrutiny and the lack of external review/audit and surface depletion of gold. The focus on the red flags has been at the expense of the numerous positive indications or ægreen flagsÆ. These include the morphology and chemistry of the gold grains, the gravity testwork, the amalgamation results, the role of external consultants, the results of a review by one of North AmericaÆs leading minerals auditing groups, the behaviour of the gold at surface and the presence of references to visible gold in the drill logs. The flawed nature of the discussion of the technical facts surrounding Busang has prevented a meaningful and informed discussion about what actually happened and has, therefore, prevented the formulation of meaningful remedies for the future.

Jan 1, 2002

By M O. Tade, M W. Sze

The particle dynamics of a mixture of coal and zircon system wasstudied in a scaled-down cold model of an industrial kiln. Thefactors investigated in the study were rotational speed (N),zircon-to-coal feed ratio (B), coal particle size (dpc) and the angle of inclination (*) of the kiln. The technique used is the residence time distribution (RTD) method. It was found that rotational speed and angle of inclination are important parameters that affect the residence time of particles in the kiln. A mathematical model for predicting the mean residence time of particles in the rotary kiln was developed. Comparisons with reported models for such systems are discussed.

Jan 1, 1998

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

By R Moreby

This paper is a demonstration of the techniques developed during an Australian Coal Association Research Program (ACARP) funded research project aimed to develop aids, principally computer based, to assist mine personnel to more efficiently manage significant incidents in coal mines. These aids include software to aid in the location of the incident, electronic information storage and retrieval, online site emergency response manuals and software to aid in decision-making.

Jan 1, 2005

Safety remains a critical priority for the Australian mineral resource industry and will receive increased focus in the future. This is particularly evident in underground coal mines where reserves are becoming deeper and more hazardous to extract. The CSIRO, through its Exploration and Mining Division, have recently delivered on two projects aimed at providing step-change capabilities in real-time risk management and hazard control. This paper describes the key outcomes of these projects.

Jan 1, 2005

The offshore Maui gas/condensate field was discovered by Shell BP and Todd on Services Limited in 1969. Subsequent appraisal drilling and negotiations with the Government led to a development agreement, æThe Maui White Paper' being concluded in 1973. Part of this agreement provided for the Government to take a 50 per cent shareholding in the field. The field is comprised of a double domed anticlinal structure containing two gas reservoirs at depths ranging from 2700 - 3000 m. Water depth is 110 m. The development plan called for two standalone steel platforms to be installed sequentially over a period of some years depending on gas demand. The first platform (MPA) was put in place in 1976 but difficulties were experienced with piling and drilling of the 12 (later increased to 14) wells did not start until 1978. First gas was piped ashore late in 1979.

Jan 1, 1994

AustraliaÆs strong position as an aluminium producer and potential magnesium producer combined with rapid market growth in the automotive industry, proximity to Asia and other natural advantages points to considerable opportunity for downstream processing and manufacture with light metals in this country. Development of a vertically integrated light metals industry in Australia needs to be pursued with vigour, as does the continued development of global strategic alliances through the value adding chain.

Jan 1, 2000

One of the major changes in the resource industry in the nineties has been the re- internationalisation of the industry. The history of the resource business has been one of companies from the developed world utilising the cash flows from their operations to explore and develop mines in less developed regions of the world. This resource development has progressively generated wealth and economic development, which in tum, has led to a new generation of exploration and mining projects.   InSouth America, Chile had led the way in a mining resurgence, now closely followed by Argentina, Brazil, Venezuela and Peru. Although Chile has long had a significant copper mining industry, the pre-nationalisation phase was driven by American capital; the current phase has been spearheaded by RTZ - BHP at Escondida with Canadian junior companies, in particular, providing major speculative impetus. The Australian junior companies have not been significant in South America.   Although Canadian and USA exploration appears to be in decline, the mining industry, particularly in gold, is buoyant in North America. Interestingly, a number of listed and unlisted Australian companies are active, particularly in United States exploration.   Australian-based companies have dominated the South-East Asian exploration scene, especially in the Vietnam region. To date, the combination of political and legislative uncertainties have failed to lead to significant resource developments in this region. The area remains one of great potential, as exemplified by the exciting developments in Indonesia.   The Philippines has a history of mining, and this has been dominated by both local and North American operators. Both large and small Australian resource companies have a presence in the Philippines, and the development of the copper-gold potential could be impressive over the next decade.   The tales of the undeveloped mineral potential of China are probably rivalled only by the supposed strings of virgin Russian orebodies! Many Australian companies appear to have looked but few have chosen to proceed with Chinese developments. There seems little likelihood that China will, in the foreseeable future, rival South America as a target for Australian and North American resource capital.   Papua New Guinea has had an active, albeit chequered history in mining, with Australia long being the predominant source of exploration and development funds. The developing nation status of PNG has generated extreme uncertainty, with the current exploration scene all but dead. Most recently, the international flotation of Lihir Gold has tested the international and Australian investment community's commitment to PNG resource development.   The Australian exploration scene continues buoyant, although dominated by gold. The base metals scene is generating, on average, one significant base metal mine developed every couple of years. This is probably the fastest rate of significant base metal development in Australia's history.   The gold scene has been one of incredible dynamics, and there is no evidence that this momentum is waning. The development of new exploration techniques, together with a number of the companies reaching a critical size, has added to the momentum in the industry.

Jan 1, 1995

Mother Nature controls, technical professionals model and miners decide. Decisions to explore, mine and mill. Mine decisions, mine design, planning and scheduling are subject to the quality of models û geological models, geotechnical models, resource models, density models. The closer these models are to reality, the more accurate the predicted outcome. So why is it we delegate the modelling tasks to the most junior and least experienced people? If we insist on this, we need to support them û to provide them with æexperience acceleratorsÆ. Technical mentoring is the most effective way to provide the right information at the right time. When this information (read skills) is supplied at the right time we can inject experience into the quality of our modelling and into our decision- making processes. The objective of this paper is to share those behaviours and manners that foster relationships and create frameworks for skills and experience transfer. Central to this is an understanding of how adults learn, an understanding of the basic rules of mentoring etiquette, and the three keys to building meaningful mentoring relationships. An understanding of adult learning processes and styles provides a structure within which a mentor can understand the learnerÆs perspective. Understanding the world from the learnerÆs point is critical to selecting the right language to engage, teach and transfer skills. Basic rules of mentoring etiquette like timeliness, respect and trust need to be brought into the consciousness so they can be agreed on and monitored to prevent conflicts in cultural and generational norms between the mentor and the learner.Meaningful relationships hinge on the three behaviours: truly listening, rather than just hearing; understanding the technical issues within the WIIFM (whatÆs in it for me?) question; and facilitative behaviour. Stronger and more meaningful technical mentoring relationships within our industry will bridge the generational gap and ensure we can capture and capitalise on the wealth of grey hair experience and develop an informed group of young decision-makers.

Jan 1, 2006

Technology is playing an increasingly large role in the operations of our mines. There is a temptation to regard the implementation of technological systems as the objective itself when, in reality, systems are used to support a business process. Only when the process succeeds will the systems be seen to succeed. Understanding the distinction between system and process is critical. This understanding, together with the resultant holistic approach, is considered to be critical to successful implementation and operation of Mine Control process. This paper examines the critical factors essential to success in establishing and sustaining a Mine Control process that maximises benefits to an operation. These factors have been developed during the author's experience of nearly 30 years in Mine Control projects across over 50 sites. Each factor is discussed in relation to real world examples at well-known mines.

May 1, 2010

India is on fast economic growth. Even in the turbulent years of global crisis, it could achieve a growth of over eight per cent. In recent past, Indian Government has been contemplating a faster growth in all the sectors of economy so as to make the nation an economic power in the world.Steel is a versatile material. It has its role in most of the major industrial activities, such as infrastructure, automobiles, urbanisation, consumer durables and other. In other words, steel is a part and parcel of industrial expansion, urban and rural development. It is rightly admitted that steel acts as pillar of any development model. Volume of steel consumption is the barometer which measures economic progress and/or industrial status of any country.India and China are the two countries in Asia which have the significant impact on the global steel industry. Of course, China is much ahead of India in consumption level of steel.

Dec 6, 2010

The minerals industry focus over much of the past twenty years has been on cost reduction and production growth supported, but not driven, by technology improvements. Mergers and acquisitions, and the demands of financial markets, have been high priority items whereas research and development and technology based innovation have received less attention and have been cut back in many companies. Technology improvements will be critical if the industry is to make progress on the stated aims of improving energy efficiency, reducing water usage and maximising recovery from deposits. They will also be important for improving capital efficiency and in treating difficult deposits. However the role technology based innovation will play both in the overall industry, and within individual companies, during the next decade is quite uncertain. There are major challenges in progressing technology based innovation in an industry with limited technical resources which is dominated by long life high capital operations. Specific opportunities for energy and productivity improvements exist but face significant technical and structural barriers that need to be overcome if the industry is to significantly improve performance. Current evidence suggests that changes in approach will be needed for these improvements to be realised. Recent studies in the United States and Canada have highlighted the wide range of energy performance across the industry and the scope for marked improvement from both incremental improvements and increased research and development. Comminution, material transportation and underground mine ventilation were identified as high priority areas. Opportunities within these areas are discussed both in respect of specific technologies and in how they may change performance. The role of open innovation as a source of new technology is also discussed. This is an abstract only. No full paper was prepared for this presentation.

Sep 13, 2010

By J Wheeler

The objective of this paper is to examine the operation of high frequency screens in closed circuit grinding, where the outcomes achieved indicate favourable economic gains at the comminution stage and downstream processes, including flotation, dewatering, and filtration operations. The classification process in grinding circuits has been slowly evolving within the last century. The history of classification devices brings to mind rake classifiers and spiral classifiers, which although having higher efficiencies compared to hydrocyclones, were not able to keep pace with the evolution of concentrator equipment treating higher tonnages. This higher tonnage throughput has tended to drive the concept of utilising hydrocyclones as the classification stage in closed grinding circuits. The comminution process is commonly the most energy intensive stage of mineral processing. Researchers have determined that the classification stage in the comminution process has the greatest potential for improvement. This paper is intended to inform mineral process engineers of the benefits that high frequency screens offer over hydrocyclones. This will be done by reviewing the purpose for the evolution of classification in the comminution process, documenting past and recent studies, and explaining the modern technology that is currently available.

Aug 8, 2011

By B Stump

Reliable particle size analysis in minerals processing plants is a critical factor to the economic return of a plant. As recovery of valuable minerals is compromised for particles outside the optimal size range, effective and reliable particle size analysis is more crucial than ever, particularly in the current upswing of the global commodities market. Inefficient particle size analysis can lead to excessive over-grinding, thereby significantly increasing energy consumption and reagent costs, whilst negatively affecting process operation, thickening capacity, water recovery and tailings disposal.Australia’s first installation of a particle size analyser in Iron Ore has been monitored with great interest by the industry. Previously, manual size sampling at Rio Tinto’s Paraburdoo fines processing plant involved off-site sample analysis, with a turnaround measured in days. The Outotec PSI® 500 particle size indicator, commissioned in July 2009, takes approximately three minutes per line at site.The paper will include details on the following:• plant description,• sampling design,• PSI® 500 analyser functionality description, and• key learnings from site.

Jul 11, 2011

By P G. Hicks

The influence of feed size and pulp density on the specific rate ofbreakage of quartz was investigated. Plots of log fraction of feedremaining within the feed size interval against grinding time allowed the application of the first order grinding model to be examined. Substantial non-linearities were observed for all feed sizes due to environmental and material factors. For feed sizes above 1.3 mm, the specific rate of quartz breakage was higher with rod milling than ball milling, but below this size the reverse was true. Material that remained in the feed size interval after the initial grinding broke more slowly in subsequent grinding than the original feed material. Grinding media and time as well as feed size influenced the effects of pulp density on grinding. More dilute pulps (eg 50 per cent solids density by weight) were favoured for higher rates of breakage in rod milling but for ball milling, the optimum pulp density appeared to be 60 to 70 per cent solids by weight.

Jan 1, 1998

This paper presents an overview of the current status of mine water management in South Africa. The regulatory framework within which mine water management operates is set out, based on the principles and policies embodied in the relevant legislation. The status of the gold and coal mining industries, with regard to water management, is presented on the basis of studies that have been undertaken to develop water and salt balances for these industries. While the data is not available to quantify the status of ARD in South Africa, the range of typical mine water quality problems faced by South African gold and coal mines is presented. The status quo, problems and challenges relating to mine water management are presented and discussed. It is shown that, while there have been major strides in the last decade, and mine water management and treatment in South Africa has moved onto the forefront of mine environmental management, important problems still persist. There is still a significant amount of improvement required, particularly in the field of prediction of water quality deterioration and the application of such predictions to the identification of management actions that can be applied to prevent or minimise mine water pollution in the shortmedium- and long-term.

Jan 1, 2003

By A M. Lechner, S Arnold, M J. Gillespie, P D. Erskine, D R. Mulligan, A T. Fletcher, A Gordon

Mine ecological monitoring schemes are often conducted only to address compliance and in some cases do not have the sufficient statistical power or understanding of ecological systems to assess, quantitatively, the meeting of rehabilitation targets or mine impacts. Monitoring schemes for rehabilitation commonly rely on analogue sites or premining baselines (reference sites) to assess whether rehabilitation sites are ecologically similar and thus successfully rehabilitated. In the case of monitoring for mine impacts, if the impacted sites diverge from reference data, the site is considered to be impacted. Fundamental to any monitoring scheme is testing the sampling design to ensure that it can detect these differences if they are present through adequate sample sizes (ie statistical power). However, a good understanding of the ecological system is required to ensure that differences detected are ecologically significant. Modelling ecosystem properties can provide a quantitative understanding of how ecosystems change over time and space, in response to natural environmental variations and thus aid in determining significant ecological differences. Furthermore, modelling methods can be used to predict future ecosystem states. Within the ecological literature, guidelines for robust statistical monitoring designs and modelling methods exist but are not routinely being used in the mining industry. This paper uses simple examples to discuss: problems with current compliance monitoring methods; importance of robust statistical techniques; and how modelling can assist rehabilitation assessment and guide monitoring schemes. The aim of this paper is to describe general monitoring and modelling methods that could be potentially used for mine site monitoring and closure assessment. These methods are often considered by mining companies as an extra expense that provide little practical benefit, and the domain of academia; however, engaging these methods may be more cost-effective in the long-run than conducting untargeted monitoring schemes that give no confidence to regulators on whether rehabilitation criteria have been met. Furthermore, monitoring programs in mining contexts provide a good opportunity to better understand long-term ecological patterns and test the application of more rigorous modelling approaches as the life of many mines tends to be greater than ten years.CITATION:Lechner, A M, Arnold, S, Fletcher, A T, Gordon, A, Erskine, P D, Gillespie, M J and Mulligan, D R, 2012. Embracing modern ecological methods - Monitoring and modelling for mine closure, not compliance, in Proceedings Life-of-Mine 2012 , pp 25-32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By W Akpan

The Royal Bafokeng community in South AfricaÆs North West Province represents a unique case in Sub-Saharan Africa in terms of its positioning in the natural resource economy. It receives royalties directly from mining firms for the extraction of Platinum Group Metals, which include platinum, ferrochrome, rhodium and palladium. In 2007, royalty income of about R290 million (approximately US$32.2 million) was reported. Such direct revenues have enabled the community to invest in educational, medical and other social infrastructure, thus complementing governmentÆs social provisioning efforts. Indeed, the Bafokeng community owes its present-day modernisation efforts to mineral rights, and in particular, the legal-institutional arrangement that has enabled it to play an active role in South AfricaÆs lucrative extractive economy. However, the distribution of platinum wealth in this community is not only uneven, but also appears to have had little impact on the broader socio-economic conditions in the community. Despite claims by community leaders of heavy investment in education and skills development, the community continues to be faced with very high levels of unemployment, illiteracy, sprawling informal settlements, poor access to medical facilities and malnutrition. This paper examines the sociological paradoxes and contradictions thrown up by the approach adopted to involve community members in the mobilisation of mining royalties for developmental ends. The central argument is that the current æmodelÆ contradicts the communityÆs stated goals of using platinum wealth to drive up broad-based development and modernisation. This is mainly because it leaves out the vast majority of community members, who are uneducated and unskilled. The core analysis is based on pilot data from an ongoing study in the Royal Bafokeng community.

Jan 1, 2009

By S J. Clarke, C S. Walker

The South West Rail Link (SWRL) project involved construction of a rail line to service new residential areas in south-west Sydney. The 11 km rail line is conveyed through a short tunnel at shallow depth where it crosses beneath the eight lanes of the Hume Highway. The underpass location is one of the most heavily trafficked within Sydney’s motorway network.The New South Wales Roads and Maritime Services (Roads and Maritime), as the owner of the highway asset, had the responsibility of managing the risks to the highway and traffic associated with the tunnelling project from the pretender stage through to completion. This paper considers the primary risks and mitigation measures employed, including geotechnical investigation, and development of appropriate construction constraints and concept design of an extensive real-time survey system to monitor pavement deformation during the tunnel works.The geology comprises fresh Minchinbury Sandstone in the tunnel invert and side walls, and variably weathered Bringelly Shale in the haunch and crown. Few tunnels have been excavated in these rock types in Sydney, and there is little information relating to the in situ stresses and stress-relief deformations in these materials.During tunnel construction the monitoring data indicated unexpected surface heave of up to about 24 mm. A multiparametric back-analysis of the deformation data is presented, which provides information on the deformation mechanisms and key geotechnical parameters, including rock mass modulus and in situ stresses.The approaches and methodologies developed for the SWRL underpass were effective in maintaining the safe operation and traffic capacity of the highway throughout the construction period, and the analysis of the monitoring data provides a useful reference for similar future projects, or projects constructed in similar ground conditions.CITATION:Clarke, S J and Walker, C S, 2014. Deformation mechanisms of the South West Rail Link underpass beneath the Hume Highway, in Proceedings 15th Australasian Tunnelling Conference 2014, pp 631–640 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014