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By J E. Everett, D Linden, P Maney

In response to the implementation of a new schedule for iron ore fines in the International Maritime OrganizationÆs (IMO) International Maritime Solid Bulk Cargoes (IMSBC) Code, improved measures for the management of moisture have been developed. In particular, prediction of cargo moisture allows management of iron ore fines within the supply?chain to facilitate the safe?shipping of iron ore fines.An ARIMA model, augmented to allow for shipment tonnage, has been developed to predict the moisture level from previous shipments of the same product. The model explains about 60 per cent of the moisture variance. It was found that inclusion of other available information, such as ore composition, train/rake assays and recent rainfall at port and mine, did not add to the predictive power of the model.CITATION:Everett, J E, Linden, D and Maney, P, 2013. Predicting iron ore fines shipment moisture, in Proceedings Iron Ore 2013 , pp 17-26 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By K B. Quast

Changes in feed size distribution can have significant effects in rod mill grinding. The product sizing resulting from wet batch milling of a tin ore showed little influence on fines production after truncating the feed at either the coarse or fine end. The addition of fine material caused a less amount of fines to be produced and a possible increase in grinding at coarse sizes, although this is complicated by the changing feed size distribution. The changes in feed size distribution caused no tendency for preferential grinding of the cassiterite.

Jan 1, 1998

By Pratt V

The economic, social and political environment of the mining and minerals industries is, as we all know, volatile and affected by constantly changing international forces. In addition, the outcome of negotiations with overseas customers is often uncertain for long periods, or even unfavourable. The industries and companies represented at this Conference are in an arena of high competition, risk taking and enormous capital outlay. They are industries which our overseas markets (rightly or wrongly) have criticised for industrial relations problems, unreliable production and uncertain deliveries. They are industries which have an urgent need to be cost effective and competitive at all levels of activity.A critical factor in the mining and metallurgy industries is, therefore, its human resources and its human resource management. It requires the full use of available talent, innovation, skills and qualifications within its workforce, and the appropriate management of these resources.

Jan 1, 1985

Study on Reasonable Mineral Processing Flow Sheet of Yunfu Low-Grade Pyrite Ores Low-grade ores in Yunfu Pyrite Mining Area were investigated, in order to find an economical, reasonable and environment-friendly mineral processing technology, which is of low consumption and high efficiency in pyrite recovering, which can ensure that the quality of pyrite concentrate product is eligible for sale and the sulfur content of the discharged tailings meets the national emission standards. A flow sheet with a classification, a jigging for coarse-grain minerals and a spiral chute separation for fine-grained minerals was adopted, and the sulfur grade and recovery of the pyrite concentrate is 35.50 per cent and 86.70 per cent respectively, while the grade of tailings is only 6.70 per cent.

Sep 13, 2010

Bacteria can play a key role in the processing of 'difficult' ores. Bioleaching opens the way to potentially extract copper from vast amounts of otherwise hard to process refractory low-grade chalcopyrite. In my talk I will outline our research philosophy to develop bioleaching as a Precision Processing unit process step. In our view, Precision Processing is a sophisticated approach to mineral processing where the ultimate goal is to measure and characterise the ore body in-ground and in real time during mining, allowing the down-stream unit processes (bioleaching, in this case) to be continuously tailored and tuned via feedback and feed-forward controls to obtain the highest possible recoveries at the lowest possible cost and environmental impact. I will describe some of the work that we are undertaking to better understand the interfacial phenomena underlying the fundamental bioleaching process with the aim of coming to a Precision Processing approach. We use techniques such as interfacial electrochemistry (scanning electrochemical microscopy, SECM), AFM, zeta potential measurement, and synchrotron science to elucidate the parameters that drive bacterial selectivity and adhesion, bacterial metabolism, and dissolution and precipitation processes for model systems and real chalcopyrite ores. As examples of our research, I will discuss in some detail our method to produce and characterise micro-patterned CuxS - silica thin films as model substrates for electrochemical and bacterial adhesion work and our approach to the interfacial chemical characterisation of extracellular polymeric substances of bio-active bacterial cells. I will also cover some of our recent findings relating to measurement and interpretation of bacterial adhesion on sulfidic substrates and its implications for bacterial adhesion and substrate selectivity. After having identified and discussed crucial leaching parameters, such as pH, Eh, T, [Cu2+], and [O2], the talk will go on addressing some of the early achievements and challenges encountered in our work to design and prepare low-cost, rugged sensing devices that allow the in-situ (in this case, in-dump or in-heap) localised measurement of these parameters. I will conclude my talk by painting the picture of how the work of our group might contribute to realising the dream of transforming bioleaching into genuine high-tech Precision Processing of minerals. This is an ABSTRACT ONLY. A full-length paper was not prepared for this presentation.

Sep 13, 2010

Ladies and gentlemen, distinguished guests and fellow members of The AusIMM, good morning.   Thank you for the opportunity to address you all today, Crown Minerals are very pleased to be associated with the conference again this year, and I commend the committee on their organisation and delivery of this yearÆs event.   As you can see from the topic of my discussion, I would like to broach the subject of collaboration between ourselves û Crown Minerals û and you our clients, and convince you that we are on the right track but can each do more.

Jan 1, 2007

A key issue in maintaining the mining industryÆs social contract to access community-owned resources, is the need to be able to demonstrate professional management of resource extraction and the risk associated with mining hazards. Significant failures such as disease relating to coal dust and asbestos and mine disasters such as Moura, Appin and Gretley have resulted in judicial and legislative interventions that respond to the community outcry but do not necessarily effectively manage the longer term risk in a sector driven by new technology. With the implementation of recent amendments to the Queensland Professional Engineers Act, senior engineers in all industries including the mining industry are required to be registered and to demonstrate that they have æmaintained competency in the practice of engineering in the area of engineering for which the (engineer) is ... registeredÆ. This may be facilitated through a report produced by an æAssessing EntityÆ. These entities are approved by the Minister on advice from the Board of Professional Engineers, Queensland. Engineers Australia and The Australasian Institute of Mining and Metallurgy (The AusIMM) are the two professional bodies approved as æassessing entitiesÆ charged with facilitating successful implementation of the process established by the legislation. The scope of the legislation covers engineering enterprises in Queensland and engineering activities elsewhere that may have been designed in Queensland. There is currently a challenge to determine what the necessary health and safety competencies for the mining industry are and how the maintenance of these competencies will be assessed. The different approaches taken by the two assessing entities are compared and contrasted. At the legislative level, establishing an obligation to assess professional competency is simple, but at the level of the profession, it is new ground that warrants a substantial research and development input. The challenge is to develop criteria by which the quality of such system can be assessed. The comparison is made by considering such issues as equity, effectiveness, efficiency, objectiveness and transparency. These five indicators are considered in terms of how they are applied in other sectors and how they might be applied in the mining sector.

Jan 1, 2009

Within ten months of the first significant intersection on the Vera deposit, approval was given to proceed with a $28.3 M underground development of the Vera-Nancy gold mine. Contrary to what the timeframe suggests, the development of the underground mine was planned in a logical and methodical manner which enabled confirmation of the resource, evaluation of the orebody for mining and sufficient production to recommence milling operations at the Pajingo treatment plant. This paper describes the underlying factors on which the project was planned and developed. The approach has successfully enabled the mine to be in production 18 months after discovery without compromising any future production or potential expansion

Jan 1, 1998

By D R. Swinbourne, T Lehner

Study of the distribution of minor elements between copper matte andfayalite slag is important in determining appropriate methods tomaximise the recovery of valuable metals and the rejection of harmfulelements. Boliden Mineral AB operate a large copper smelter in northern Sweden, where they had noted that the loss of silver to the slag in the settling furnace appeared to be a direct function of the tin content of the slag. This work was aimed at determining whether or not this was a cause-and-effect relationship. Copper matte containing approximately 50 wt per cent copper and small amounts of silver and tin was equilibrated with silica-saturated fayalite slag at 1250¦C, then quenched. The matte and slag were then analysed for their silver and tin contents. It was found that there was no relationship between the silver distribution and the tin distribution. The silver matte/slag distribution ratio had a value of 120 ¦ 40 while that for tin was 2.8 ¦ 0.3. It is suggested that the most likely cause of the relationship observed at the Boliden smelter was matte entrainment in the slag.

Jan 1, 1999

By A Clark

When production targets are not being reached it is essential to determine what the operating problems are so that remedial action can be taken. It is also imperative that all persons who are part of the production stream within a mining operation know and understand what the operating difficulties and delays are so that corrective action is effective. This includes the supervisors, superintendents, planning team members and managers. A new approach recently adopted at Hilton Mine to help identify these operating difficulties has been to use short-term schedules and reports known as the Daily Shift Schedule Controls (DSSC), and the Daily Weekly Operating Reports (DWOR) respectively. These control elements have enabled management and supervisory staff to accurately identify labour inefficiencies and ultimately determine capital resources.

Jan 1, 1998

It should be stating the æbleeding obviousÆ to say that the most efficient method of recovery must be used during the testing and evaluation phases of an orebody. Furthermore, the company will be literally throwing away money by not using the most efficient recovery plant during mining. This is especially true in the case of a low concentration/high value commodity such as diamonds. Unfortunately, this economic recovery criterion is not always the driving force. Some inexperienced companies think that they can preserve capital by using cheaper, and generally less efficient, recovery plants to mine their product. This philosophy is invariably a fallacy. Furthermore, it is also important to use the correct sized plant for the proposed task. It is no use trying to use a small testing plant to treat large quantities of ore, as this may result in loss of recovery efficiency. The converse is equally true.

Jan 1, 2004

Delivery of effective plant shutdowns is primary to the business success of mining and processing plant operations. This paper sets out a methodology that starts with understanding the business objectives of the shutdown and promotes rigorous detailed planning, effective communication, appropriate governance and effective participation of plant operations personnel. The result is delivery of business effective outcomes.

Jan 1, 2004

By H He, S Tillotson, S Gibbons, J Shaw

"Water evaluation and management during mining exploration and operational activities is crucial to minimise direct and indirect operational costs and also in delivering mining companies the less tangible, but equally critical æsocial license to operateÆ.Mining is often carried out in remote areas, where the mine will be the most significant and visible user and potential contaminator of water resources. However, wherever it is located, a mineÆs use of water must be managed in the context of two key aspects: the natural parameters of the resource; its abundance, its temporal variability and its chemical and physical qualities other users of the resource; other industry, potable water supplies and ecological requirements of local habitats.It is vital, therefore, that this commodity be assessed to an appropriate degree to help establish the viability and sustainability of the mining project and identify those other stakeholders who may be affected by the mining companyÆs activities.This paper outlines the background to catchment-scale model and presents a cost-effective method for establishing a robust water baseline and creating a water management tool to be used throughout whole mine life cycle. Numerical surface and groundwater modelling has long been established as a tool for reactive management, following collation of yearsÆ worth of data. Now, using freely available remote sensing data and desk study information, analytical modelling techniques can be used cost effectively to provide mining companies with a tool for assessing and managing their water consumption requirements at the outset of a new project venture.The paper includes a selection of case studies to show how the use of analytical modelling can be used as an evaluation and management tool to help not only assess general watershed parameters and water availability but also how it can be used as a tool to provide decision makers with the information to complete æwhat if?Æ scenario assessments. The case studies illustrate how a combined hydrological and hydrogeological model may enable identification of sensitive receptors, water competition issues and contaminant migration pathways to help manage the risks associated with water consumption and its potential contamination from exploration and operational activities.CITATION:Gibbons, S, Shaw, J, Tillotson, S and He, H, 2013. Catchment-scale water modelling and its role in risk management during mining exploration, in Proceedings Water in Mining 2013, pp 175-188 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

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

By R Wheeler, E Stalenberg, J Lemon, M S. Crowther, D Lunney, K Ross

Gunnedah, in north-western New South Wales (NSW), including the town, the surrounding Liverpool Plains and the Pilliga forests to the west, are currently the subject of intense mining interest for coal and coal seam gas. Achieving positive outcomes for koala conservation on mined landscapes will require a sound grasp of koala ecology; and local knowledge of koala movements, tree choice and associated threats to the continued survival of koalas, particularly roadkill from increased mining infrastructure. This requires a research-oriented approach to testing ideas applicable to the long-term survival of koala populations. Our recent koala research in NSW has shown that, in 2006, Gunnedah had the largest koala population west of the Great Dividing Range, and the only population in NSW that was expanding. That prompted us to instigate a detailed study in 2008 - 2011 to determine, inter alia, whether the koalas were using trees that were planted in the 1990s to cope with rising soil salinity. Our GPS-tracking has shown that regrowth trees as young as ten years old can attract koalas. In 2009, the demise of about a quarter of the local koala population from an intense heatwave gave us a foretaste of how habitat and climate change interrelate at the landscape scale. We are now examining the optimal combinations of tree choice, and patch size and shape, for habitat restoration. This will be relevant to local coal seam gas and coal mine proposals, and ongoing mitigation actions. The Senate enquiry of September 2011 on the koala and demonstrated the intense public interest in the survival of this iconic species. Its subsequent listing for Queensland and NSW under the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999 further raises its profile and obligations for management of koalas and their habitat. It will take considerable effort to manage the Liverpool Plains koala population for the next 50 years in the face of extensive land-use changes from mining, and the attendant threats from road kill, compounded by the new threat of climate change manifesting itself as an increased frequency of heatwaves and more severe droughts. This paper describes the research that underpins these conclusions, identifies some of the research approaches needed, argues for working strategically now, rather than try to patch up matters after the event, and presents a set of guides for environmental plantings. CITATION:Lunney, D, Lemon, J, Crowther, M S, Stalenberg, E, Ross, K and Wheeler, R, 2012. An ecological approach to koala conservation in a mined landscape, in Proceedings Life-of-Mine 2012 , pp 343-352 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

The ERMS Process was developed during four years of testwork by Austpac Gold NL to overcome the severe metallurgical problems of the ilmenite atWestport, in the South Island. These deposits have been known for about one hundred years. They were originally mined for gold, and only later attracted attention as a possible source of titanium minerals.   The resource is of world scale and may exceed 20 million tonnes of contained ilmenite. Similar deposits occur at Barrytown further south and together these areas would constitute an important opportunity for export-oriented mineral development, if a viable beneficiation technology were available. Further processing is essential, as the composition of the ilmenite is well below market specifications.

Jan 1, 1993

L&M have been involved on the Shotover since 1980 when we joined Jack and Barney Ryan, who had started in 1972 with gold at $45 per ounce after a successful career as roading and demolition contractors in Christchurch. The first 85 tonne plant was a typical NZ trammel-riffle table plant with an armour plated hull for surviving Shotover floods, and was fed by a 53 tonne UH20 excavator. All this gear had to be carted in over the Skippers road on a small truck or sledge for the heavy loads. This operation was successful and generated the cash flow to sample the lower section of river and plan a second plant. To reduce fine gold losses this was planned to be a jig recovery plant and also included a vibrating screen which saved space and weight over a trammel. There are five flowlines of primary jigs and one secondary, followed by two Knudsen bowls for cleanup.

Jan 1, 1985

The Clyde Power Project, and its Clutha Valley Development forerunner, has taken widespread investigations for various hydroelectric purposes both along the valley floors upstream from Alexandra and on the higher schist terrain. As part of this work the nature and extent of many of the alluvial deposits have been resolved and the ages established with varying precision. Gold values have been approximately appraised in some areas as an element of environmental assessment.

Jan 1, 1992

Responsibility for the administration of mineral resources is divided between federal and provincial governments. The paper traces the evolution of mineral policies at both levels of government, from the end of World War II to the present. In the immediate post-World War II years, the emphasis was on supplying the raw material needs of a rapidly growing world economy. Policies favouring growth and development of the Canadian mining industry were instituted during this period. Two decades of uninterrupted expansion (the 1950s and 1960s) ensued. The decade of the 1970s was a turbulent one for Canadian mineral producers. Governments intervened more substantially than ever before. Moreover, the industry suffered from an intense period of competition for resource revenues by the two levels of government. At the same time, far reaching changes were taking place in the structure of world mineral markets. To date in the 1980s, the mineral industry has, perforce, adapted to existing mineral market structures. Mineral policies, too, have shown signs of adapting to the needs of the mineral industry. Whether the resulting mix of policies will permit the revitalization of the Canadian mining sector remains to be seen.

Jan 1, 1986

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