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Potential hlghwaJl mining reserves in Australia are large, but geotechnical and operating conditions are quite different from those where highwall mining has evolved in the USA. In order to achieve safe and effective resource recovery, equipment and procedures should be developed to penetrate 250 m in the Australian mining environment. This paper identifies key auributes to be incorporated in such machinery and methodology. These suggestions are intended to promote discussion on innovations to satisfy Australian requirements for highly productive, safe and environmentally acceptable techniques.

Jan 1, 1993

By R Justa Cámara, L M. Pinillos Lorenzana

Barcelona Metro Line 9 (Line 9) is an essential infrastructure, improving the transversal transport in Barcelona by connecting the greater part of the currently existing radial lines. The purpose of Line 9 is to create a peripheral line surrounding the city of 1.6 million people (metropolitan area exceeds five million), and includes 52 stations, of which a total of 32 are deep shafts and 19 transfer stations in a densely populated area with several geographical constraints.The tunnel has an inner diameter of 10.90 m, bored with an earth pressure balance (EPB) tunnel boring machine (TBM) in soil sections with precast concrete lining type universal ring and segments 40 cm thick.A single tunnel solution was adopted, driven by functionality and costs savings. The internal tunnel section is divided into two levels to allow for one way rail transit including the platforms in each station on each level in order to optimise the space created by the TBM excavation and comply with the operational needs. The division in two areas of the tunnel was carried out through the construction of a horizontal slab resting on the tunnel segments with a constant thickness of 40 cm at the central part of the slab and supporting side walls.CITATION:Justa Cámara, R and Pinillos Lorenzana, L M, 2014. Two transit levels in one tunnel tube – an innovation in Barcelona Metro Line 9, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 387–398 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By A S. Bamber

Mining is the oldest industrial practice on the planet with a history dating back over 3000 years. Since the early iron age ores have been extracted for use in a variety of contexts by humankind, from domestic to military, transport and more recently for complex industrial applications. Mineral exploration and extraction has evolved from the early exploitation of primary metal occurrences in relatively small quantities such as iron, gold, coal and copper, to the bulk mining and extraction of highly complex polymetallic oxides and sulfides today. Since the industrial revolution, mining practice has evolved substantially to support an increasing range and quantity of required metals and to accommodate the increasing scarcity of high-quality sources of these metals. A common response to the increasing scarcity of mineral resources has been to expand production through simple economies of scale, thus diluting fixed costs. This approach, however, is increasingly ineffective in the face of current trends, that include increasingly complex mineralogy, increasing pressure on environmental footprint - energy in particular, and increasing scarcity of capital for the construction of presently popular æmega-minesÆ. This paper examines historical trends and current practice in mineral exploitation in the light of the current global revolution in social, environmental and economic values as the projects move towards a vastly different topology for the industry for continued success in years to come.CITATION:Bamber, A S, 2012. The mining industry needs to be shaken and stirred, in Proceedings Narrow Vein Mining 2012 , pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

Australian coal mines have spent considerable capital on dragline improvements over the last two years. This has included ~$30 M on UDD conversions, >$20 M on new buckets, boom upgrades, electrical upgrades, etc. This is a natural part of the response of mining companies to technology and replacement programs. Capital expenditure is a normal part of the ongoing success of most companies. There is however, a tendency for some people to rely on the capital alone to provide the ongoing improvements in equipment productivity. Implementing new technology through capital expenditure is only part of the equation in continuous improvement. For 80 - 90 per cent of the year, the operator controls the productivity achieved by the dragline. Variation between operators is huge. The average standard deviation in productivity is 12 per cent and maintenance impact is over 40 per cent. Robbins 2003, states: Contrary to what we were taught in grade school, we werenÆt all created equal. Most of us are to the left of the median on some normally distributed ability curve. Further, he states: The issue is knowing how people differ in abilities and using that knowledge to increase the likelihood that an employee will perform his or her job well. There are two options for reducing variability between operators; improving operator ability and getting the machine to take over what the operator is doing (automation). Dragline automation will be discussed, however, this paper will focus more on the æhuman factorÆ and how to establish a dragline with minimum variability between operators.

Jan 1, 2005

The Martha Mine is an open cut operation situated in the midst of Waihi town which has been operating since 1987. Since then it has produced some 700,000 ounces (oz) of gold and 4,000,000 oz of silver from an epithermal vein system. It was previously worked by underground methods from 1880 to 1952 to a depth of 600 m producing 5 million ounces (Moz) of gold and 30 Moz of silver. The licensed reserves are scheduled to be mined out early in the year 2001. An additional economic resource of over 750,000 oz of gold has been identified which can be accessed by deepening the pit a further 50 m along the main Martha vein. This would extend the mine life to the year 2007. Applications were lodged on 4 July 1997 for the necessary resource consents, discharge permits and variations for the current Mining Licence conditions. The extension project requires approval from the District Council, Regional Council and the Ministry of Commerce. The consent and permitting process is extensive because of the urban setting of the mine. An approach to keep the extension as similar as possible to the current operations was adopted to give the community and authority confidence in the proposed extension. This paper summarises the extension detail and the permitting requirements it has had to address despite the extension being "more of the same". The permitting process has been exhaustive with little recognition of the standards already achieved in protecting the environment which are recognised worldwide.

Jan 1, 1997

Iron from the blast furnace constitutes the starting point in steel production and any increase that can be made in iron production will bring about important repercussions in a long line of processes. Coke constitutes a major item in furnace operation and consumption at the Port Kembla Works of Australian Iron & Steel Ltd. has been approximately 1,850 lb. per ton of iron produced on ore practice, or 3,000 tons per day.For many years coke quality has been subject to much criticism by furnace operators throughout the world, sometimes with little real grounds. Whatever the merits of previous arguments, and they were no doubt two-sided, the development of bigger furnaces has focused attention on coke strength. At the same time a decrease in the quantity of good quality coking coals available to many plants has stimulated research in this field.Extensive coke research has been carried out overseas, and in Australia the.B.H.P. Organization is now actively doing likewise in its Central Research Laboratories at Shortland near Newcastle, N.S.W., and works research groups at Newcastle and Port Kembla Steelworks. Similar work has been initiated in the beehive coking industry. Such work is in its infancy and this paper will outline the direction of the activities at Port Kembla rather than propound specific solutions.At Port Kembla good quality coking coals are readily available from the IIIawarra coalfield. The seams generally mined for coking are Bulli and Wongawilli and to a much smaller extent Tongarra. Characteristics of these coals appear in Table 1.

Jan 1, 1958

By X Dahe

SLon vertical ring and pulsating high gradient magnetic separators possess excellent mineral processing ability and have been widely applied to process oxidised iron ores. SLon centrifugal separators are applied to clean the SLon magnetic concentrate and remove quartz and other gangue minerals associated with a small portion of magnetite.This paper introduces the application of this technology in Hai Nan, Da Hong Shan and An Shan for processing oxidised iron ores.

Jul 11, 2011

Plenary SpeechI have given considerable thought about what I might say to such a group of professionals, given that I am not an extractive metallurgist. It was immediately apparent that I would quickly be out of my depth if I tried to present some technical aspect of extractive metallurgy. So, instead I thought it might be useful to review the subject from the minerals business management point of view in order to improve understanding for the extractive metallurgist who some times finds it difficult to comprehend directions being given by management.

Jan 1, 1992

By C M. Côte, P Bolz, L Pagliero, M Edraki, M Shaygan, P Erskine

Mines in Queensland must now prepare a Progressive Rehabilitation and Closure (PRC) plan, with the requirement to justify the selection of the post-mining land use (PMLU) for each rehabilitation domain. Given that there are nearly 200 mines who must undertake a comprehensive PMLU assessment, there is a need to develop methods that will minimise the duplication of effort. As part of a broader initiative on innovative post-mining land use planning, this project undertook a regional analysis of the technical suitability of several PMLUs.

Aug 2, 2023

By S Yang, J Wang, J G. Ning

A series of conventional dynamic uniaxial compression (CDUC) tests and coupled static-dynamic loading (CSDL) tests were conducted using a split Hopkinson pressure bar (SHPB) system to explore the dynamic mechanical behaviour and fracture characteristics of medium sandstone on a microscale in the laboratory. In the CDUC tests, the dynamic uniaxial compressive strength of the medium sandstone was rate-dependent, while the dynamic elastic modulus was not dependent on the strain rate. Then, we proposed a generalised model to characterise the rate-dependent strength from 17.5 s-1 to 96.8 s-1. In the CSDL tests, with increasing initial pre-static stress, the dynamic elastic modulus and dynamic strength increased nonlinearly at first and then decreased. The results show that two classical mechanical types (ie Class I and Class II) are observed from the dynamic stress-strain responses of the CDUC and CSDL tests. By means of scanning electron microscopy (SEM), the micro difference of post-loading microfracture characteristics in Class I and Class II behaviour was identified. In Class I behaviour, intergranular fracture (IF) usually initiates at or near the grains, most cracks deflected along the grain boundaries, resulting in a sharp angular edge, then coalesces to the main fracture surface that splits the specimen along the direction of stress wave propagation. In contrast, Class II behaviour results from the combined IF and transgranular fracture (TF).

Nov 29, 2022

The ore deposits investigated are composed primarily of hcmatite and can be grouped into three categories depending on the amount of leaching of silica and carbonate which has occurred from the original iron formation, and on the amount of recrystallization of the hematite. Minor constituents are magnetite. goethite, and quartz.Texturally. there are five different types of hematite, formed at different stages during the genesis of the ores.These are1. anhedral hematite grains formed by recrystallization of hematite already present in the original iron formation.2. hematite formed by martitization of euhedral magnetite, 3. massive aggregates of fine- to medium-grain hematite formed by recrystallization of (l) and (2).4. tabular or prismatic hematite grains occurring around the boundaries of the massive aggregates or martite euhedra. and in fractures and5. specular hematite. which is present in fractures in ore types (l) to (4).Minor and trace-element analyses, determined using an electron-probe microanalyser. indicated that only silica (less than 0·01 per cent) and cobalt (less than 0·002 per cent) were present in the magnetite and hematite from unaltered iron formation and in the hematite from the ores. Low concentrations of trace elements are typical of magnetite in ores formed as marine precipitates. On the basis of the analyses alone. it proved impossible to distinguish between the five hematite types. A determination of the variation in rare-earth trace element contents between iron oxides in the iron formation and iron oxides in the ores indicates that the rare earths were depleted during ore formation. A possible explanation is that they were removed in solution with silica as it was leached from the iron formation.

Jan 1, 1971

By L Chaffey, M Buckland

The minerals industry has enormous potential to positively contribute to sustainable development and many leading companies have concluded that their long-term success is directly linked to their ability to leave a lasting positive legacy. While there are many examples of success, there have been failures as well and much work has been done in recent years to define the role of the minerals industry in sustainable development and identify the key elements for success. In the past, our sector could point to the taxes and royalties it paid, the exports it generated and employment it created and felt confident that its contribution would be recognised and duly acknowledged. This is no longer the case. Critics of the industry have highlighted resource-rich countries that have failed to capitalise on their resource wealth and have arguably lower standards of living than their resource-poor peers û the æresource curseÆ hypothesis. Recent research has done much to clarify the factors that contribute to a countryÆs success or failure and all stakeholders in the industry now need to include these learnings in their approaches going forward. We know that our long-term success relies on embedding a company- wide approach to sustainable development into all aspects of our business operations. In this paper we highlight BHP BillitonÆs experience in the development and implementation of policies and systems designed to enhance our contribution to sustainable development. We detail the business drivers for excellence in this area and the key external codes and initiatives that have shaped our approach. The values-based BHP Billiton Charter, Sustainable Development Policy and associated Health, Safety, Environment and Community (HSEC) Management Standards are central to our approach. Implementation is reviewed through our HSEC audit program. One area in which we have placed particular emphasis is our approach to community development. BHP Billiton has a corporate target to contribute one per cent of its pre-tax profit on a three year rolling average to voluntary community programs. As our profit stream has increased with the minerals boom this is approaching an A$100 million commitment. In our paper we detail how we are working to ensure we maximise the value of this contribution for our communities and our shareholders.

Jan 1, 2006

By Juniper LA

ERM Consultants Pty Ltd was established in 1980 for the purpose of introducing a disciplined coal technology and power station planning service, to support Australia's efforts in establishing a major export steaming coal industry. At that time, major coal exploration programs were mounted on more than 50 potential export coal deposits with proven open-cut reserves to export 200 Mt/a of coal. The fact that Australia achieved an export trade of only 30 Mt/a, equivalent to the energy requirements for a population of around 5 million people, illustrates the very small achievement to date. The main reasons for this small export steaming coal growth have been: 1. Failure to convince potential overseas coal buyers of the benefits of coal-fired power generation, and the ability of proper power station design to overcome environmental problems, and achieve reliable operation and long life when burning Australian coals. 2. Failure to promote Australian power engineers to advise on the use of Australian coals, resulting in Northern Hemisphere power station experience dominating in market countries. 3. Failure of governments to draw on privately practising Australian power engineers and coal technologists in technical workshops, presentations and assistance to overseas countries, to ensure that personnel whose business it was to serve the follow-on needs of countries were readily available. The result of these failures has been that: 1. Only a fraction of prospective overseas coal-fired power projects have proceeded. 2. Australia has had no influence in the design of overseas power stations to ensure that potential customers would be confident that Australian coals could be reliably burnt in their boilers.

Jan 1, 1987

By A Murphy

Mining plants and infrastructure, and the decisions made by their designers, can have large impacts on their environmental and social context, commonly referred to as the site or plant footprint. They can also be the source of constructive contributions to sustainable development when designers are enabled via the information, systems and tools to incorporate sustainability in engineering processes. A facility’s footprint and the project’s contribution to sustainability – economic, environmental and social aspects – are now key considerations in regulatory approval processes and are the fundamental drivers of support, or opposition, from the project’s stakeholders.Historically, plant and infrastructure designers have not been well integrated with the environmental and social professionals who are engaged to pursue regulatory approvals. Despite this, many objectives central to technical and process engineering have in fact contributed positively to a facility’s footprint and indeed its contribution to sustainable development. Examples of these objectives include increasing process and energy efficiency, and minimising the quantities of waste requiring disposal. With the framework of sustainability, mining plant and infrastructure designers are indeed at the forefront of incorporating sustainability into resource industry projects and are central to the process of obtaining regulatory approvals and ongoing stakeholder support. The process of incorporation starts with a shared understanding of sustainability and sustainable development, and continues with project processes that facilitate information and knowledge exchange throughout the project life cycle.CITATION:Murphy, A, 2014. Incorporating sustainability into mining plant and infrastructure design, in Proceedings Life-of-Mine 2014 , pp 637–646 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By P J. Bangerter, J Pan

Optimising for Net Present Value (NPV) with a strategic optimiser such as COMET, Prober-E, Blaser or Minemax has hitherto lacked a dynamic method for analysing the so-called third-order outcomes (such as Carbon emissions) of optimisation within life-of-mine planning. Optimisation, per se, has natural effects on carbon emissions in a life-of-mine plan. Contemporary strategic planning employs a mathematical optimiser to make sense of non-linear data (ie a block model) and produces a best-NPV optimised mining schedule, within a set of constraints. The very act of optimisation influences emissions, and in a dynamic way.

Aug 2, 2023

By Morgans DJ

The aim of this paper is to highlight the social aspects involved in the preparation of environmental impact studies (E.I.S.'s) for mining developments. In particular, the paper will reveal that the social information provided in such E.I.S.'s can achieve much more than simply satisfying government requirements. Such information can form the basis of a strategy to deal with the settlement of a mine workforce in either an existing or newly developed community. A strategy of this type can go a long way towards avoiding many of the social problems and related industrial disputes often created in such circumstances. It will also be of significant benefit to the mining company in negotiating its infrastructure package with the local authority.

Jan 1, 1987

The selection and implementation of the right technology for a project is critical to the future development of the resource industry. It is essential for companies to ensure ongoing competitive viability that where practical new or alternative technology be adopted. Analysis of historical data relating to development of resource-based process plants provides an enlightening insight into the key factors which influence their success or failure. The adoption of new technology does not guarantee the success of a project. The outcomes of this analysis have been used to develop some general guidelines and principles the author believes are useful in the selection and implementation of new or alternative technology in resource projects. This paper is available as a PowerPoint presentation only.

Jan 1, 2006

By E Topal

Risk and uncertainty are attached to mining projects, and making decisions, hedging, future investment and evaluation of mining projects depend on forecasting the future price. The future technologic developments in mining will be primarily influenced by the future commodity prices. A few approaches, with different confidences are proposed to predict price movement in the future. This research introduces a new comprehensive version of the mean reverting jump diffusion model for natural-resource commodity prices. The novel model proposes that the historical data of mineral commodities have three terms to demonstrate fluctuation of prices: mean reversion component, diffusion component and jump component. The model calculates each term individually to compute the future prices of mineral commodities. Subsequently, in the second section of the paper, the model is implemented for monthly historical data of gold price from January 1968 to May 2008. This research is investigating the relationship between the historical oil price and inflation with the gold price. This is followed by a future estimation of gold price fluctuations up to 2018. The results from the application of this new method are discussed in the context of how they accurately replicate the historical gold price and how they can predict the future gold price.

Jan 1, 2008

Production targets are the basis for almost every decision made by operations personnel in the daily operation of a concentrator. It is the production targets that determine how the plant is operated and therefore determine its efficiency. However, to achieve maximum plant efficiency production targets must be relevant to the process and achievable.In RoseberyÆs case, for many years, production targets were taken from budget data which, with the exception of mill feed tonnes and grades were carried forward from the previous budget. The zinc concentrate grade target was fixed at 57 per cent Zn, a long-term average; it was the accepted æstandardÆ for Rosebery. Historical data showed this target was never consistently achieved and plant efficiency was highly variable.Investigations into the possible causes for the variable performance ruled out plant and mechanical issues. Despite the Rosebery concentratorÆs age the plant and equipment are more than serviceable and reliable. The mineralogy of the ore and specifically the iron content of the sphalerite was found to be the most significant determinant of zinc concentrate grade. It was found with increasing frequency that the zinc grade of the sphalerite in the ore was below the zinc concentrate grade target. Consequently on these occasions attempts to meet the required concentrate target destabilised the process resulting in plant inefficiencies.Using the correlation between iron and zinc, data modelling was able to accurately predict the maximum zinc concentrate grade achievable for any ore type. By using on stream analysis instrumentation the operations personnel are now provided with constantly updated concentrate grade targets. By knowing the mineralogical limits of the ore at the time it is being treated process stability is maintained allowing plant efficiency to be optimised. This has resulted in a step change in plant performance and a significant increase in revenue.CITATION:Harris, G R, 2012. Developing and implementing ore-specific targets for the Rosebery Concentrator, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 321-324 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By H Allday

The mining industry’s attention has shifted over the last decade with the recovery from the downturn resulting in greater development of innovation and new work methods in a bid to remain competitive and deliver higher productivity. The emphasis on cost reduction to improve profit margins has primarily been the focus of the “work smarter” campaigns embraced within the industry. But is this strategy holistically the best-for-business, or does it place a ceiling on revenue opportunities and inhibit mining companies from truly maximising value? Businesses need to maintain a balance between active cost management and revenue generation often resulting in cost reduction strategies at site level. These strategies have merit, assessing areas of cost wastage across operations and creating space for opportunity. However, this potentially can create distractions from the goal of enabling growth and lead to the sacrifice of quality and delivery. Focusing too heavily on cost reductions without addressing revenue generation is an unprofitable lens to look through, and the relationships between cost, revenue, quality and profit margin can often be overlooked resulting in missed opportunity to maximise value. How these relationships are effectively employed by mining companies to reap the rewards from an overarching corporate perspective down to site level remains a fluid concept depending on the nature, operating market and strategy of the business. A common directive from businesses to their operations is to strive for greater profitability and productivity. The quantification of these requirements, and the nature of the cascading message delivered, impacts the methods employed by the operational team to meet the expectations of the business. Cascaded strategies, if not delivered with appropriate participation and buy-in can often be perceived to be knee-jerk and create frustration for operations who are squeezed to deliver on expectations by slashing site costs. This squeezing is not only felt by the mining operation but at the individual level and can result in increased team stresses. In some cases, this may also steer behaviours towards activities that result in corner cutting and an elevation of operational risk, potentially increasing associated incidents and injury. Driving down costs by any means can create an unhealthy tunnel vision where value is no-longer assessed for best-forbusiness results. By flipping the viewpoint to a value-based approach revenue opportunity may be realised and potentially exceeded, however this opportunity may be missed if value is over shadowed by a cost heavy focus. By analysing a selection of real operational cases (ranging from mining contractors through to in-house mining giants), it becomes apparent that practical revenue maximisation strategies are not only key to an increase in value and cash flow but to a stronger understanding of business drivers for sites and operators alike. In the cases evaluated additional revenue opportunities are foregone in favour of cost reduction strategies resulting in negative impacts on the associated operations and wider businesses. Alignment towards value generation is king. If strategies are not implemented focusing towards value and revenue maximisation, the opportunity loss experienced by mining operations could continue be great and the question should be posed; when the next up-turn hits will operations be ready to reap the rewards or still have a glass ceiling above their heads?

Mar 15, 2021