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By T Napier-Munn, D J. Bradshaw, M Chauhan, L Keeney

An important aspect of geometallurgy is quantifying mineral processing attributes, which leads to improved orebody understanding. One of these attributes is flotation performance. Several methods have been developed as indicators for flotation performance, including batch testing leading to kinetic information and the standard grade-recovery curve. This paper makes a preliminary statistical comparison between a newly proposed geometallurgical batch flotation procedure and the æstandardÆ batch flotation test commonly used to measure flotation performance in the laboratory. The new test uses much less material than the standard test, and is much faster. It is concluded that the new method follows the final recovery of the standard method well, suggesting that it will be effective in reflecting ore variability for geometallurgical purposes. Comparison of the methods based on the full grade-recovery curve shows less agreement, but this may be due to the fact that the curve is sensitive to the particular experimental set-up and conditions, which make such comparisons quantitatively challenging. Further development work is therefore planned.CITATION:Chauhan, M, Napier-Munn, T, Keeney, L and Bradshaw, D J, 2013. Progress in developing a geometallurgy flotation indicator, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 201-206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By S Walters

The emerging discipline of ‘geometallurgy’ is not new but is becoming increasingly recognised as a discrete and high-value activity. Geometallurgy involves a quantified and spatially constrained approach to ore characterisation in terms of relationships to critical processing performance behaviours. A key outcome is enhanced economic optimisation of mining and improved risk management tools.Industry recognition of the need for large-scale, integrated research to support this emerging area resulted in commencement of a major ongoing initiative in mid-2005. The AMIRA International P843 ‘GeMIII’ project (Geometallurgical Mapping and Mine Modelling) is a cross-discipline collaboration involving a number of world-class research organisations supported by over 20 industry sponsors.The project is delivering integrated tools and methods which link intrinsic rock characteristics to prediction of mineral processing performance. These indices must be capable of spatial distribution in 3D resource models and incorporation into mine planning and optimisation. A key aspect is provision of new cost-effective tools and methods which can provide the large numbers of measured and estimated data points required to undertake effective modelling and spatial distribution. The integrated methodology and enabling technologies being developed through the ongoing AMIRA GeMIII project are outlined, together with implications for supporting industry best practice.

Sep 5, 2011

The phrase "Total-Energy" has, during the past few years, become widely used to describe a wide range of very different operations. However, if accurately described they all have one basic factor in common - energy usage is optimised with the prime mover being powered by gas or oil to generate shaft horsepower and the products of combustion being put to some use. The item which distinguishes a Total Energy system from any other engine or turbine driven project is that orate pains are taken to utilize the waste heat, whether this be in the form of exhaust gases and/or engine jacket ling water. n areas where grid supplies of electricity are readily available, the economics of most projects undoubtedly hinge upon the successful application of waste heat. However, there has been a growing awareness of other benefits, such as reliability of supply, which can be incorporated into the system. In particular these factors sway managements of hospitals and companies with complex computer facilities to examine closely the feasibility of Total Energy, Consequently, in America for example, where many systems have proved themselves the list of applications is wide - shopping centres, apartment blocks, office buildings, airline terminals, universities, schools, motels. And these do not cover the industrial sectors where the range is wider. The total number in North America is now approximately 500 and this to some extent-speaks for itself. In Australia, the real work involved in carrying out feasibility studies for Total Energy is only just beginning. 'in some quarters, the concept is not well received in that it is too new. Therefore, a typical approach is to play safe and wait until some other company has proved its operation "under Australian conditions". This is certainly a realistic approach when considering something revolutionary but as far as Total Energy.is"concerned all the individual components and sometimes combinations, (engines, generators, boilers, air-conditioning units) have been in operation for many years. The only innovation is that they are now all being brought together under one roof. This should not be forgotten when the question "where can I see something like this operating?" is asked.

Jan 1, 1970

By S Grimsey, E Janetzki, J Emery

Floor failure on the longwall face is a complex problem due to the dynamic interaction between the surrounding strata and powered roof supports involving multiple variables. It can also be highly problematic and costly when not well understood as there are significantly less remedies available post event. This was the early experience at the case study mine where significant lost time was incurred due to unplanned delays in the first two panels. To detect and prevent such occurrences is clearly the best approach, hence a tool to predict both floor failure occurrence and magnitude prior to mining was developed. Several parameters were determined as the key drivers for the failure events that had been experienced at this site. These parameters were, in list of influence from highest to lowest, material strength, retreat rate and the presence of water. The parameters were evaluated using a semi quantitative risk rating system ‘Heave Risk’ and given a weighting per their apparent influence. This ‘expert system’ methodology was selected as the use of risk rating systems in underground coal mining is well established. The heave risk model was first applied to previously mined panels. It accurately identified all areas of known major floor heave, with clearly defined areas of low and high risk apparent. The heave risk model was then used prior to mining and evaluated post mining based on observed conditions. It was found to also be highly accurate for prediction. The variability of each parameter and its influence on the overall risk rating is illustrated and discussed.

Nov 29, 2022

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

By R Farana

The future challenges in mining instrumentation, mainly on future intelligent mines, are to continue providing instruments with the highest level of reliability at the lowest possible cost, and also to take advantage of technology existing in other industries and to adapt it to the mining context. New wireless instruments (smart sensors, smart actuators, smart controllers) would also be very useful, as well as instruments fully adapted to the monitoring of large movements that are observed, in both underground and open pit mines. Mining instrumentation is found to various degrees in most mines, both open pit and underground. Smart mining instruments present a certain number of aspects specific to the environment in which the instruments are installed. Namely, the instruments can be installed either for short-term or long-term purposes. The mining industry is always looking for useful instruments that can provide relevant information on ground behaviour adjacent to mining stopes or permanent infrastructure. The instruments must meet the various criteria, and must also evolve with the new mining technologies that are continuously being implemented. A strong collaboration between the mining industry, research organisations, and instrument manufacturers is the key to meeting these objectives. This contribution describes the current trends on smart sensors and smart instrumentation with Wireless LAN support.

Jan 1, 2003

Detailed cash flow forecasts have always been almost essential as a basis for judging the viability of proposed new mining projects. In recent years attempts have been made explicitly to take account, in such forecasts, of the uncertainties surrounding the assumptions upon which they are based. With the risk analysis approach, Monte Carlo simulation of the cash flows indicates in probability terms the combined effect of these uncertain basic assumptions. While the use of risk analysis has been widely discussed, few specific applications to real projects have been reported. The application of such an analysis in the feasibility study of the large new Deelkraal gold mine presently being established on the Far West Witwatersrand gold fields by the Gold Fields Group in South Africa is described in the paper. The paper also indicates how one of the major sources of uncertainty, namely the gold content of the ore, can be`quantified in objective probability terms. This feature distinguishes the application fran other published accounts in which only subjective probability assessments have been utilised.

Jan 1, 1977

The Golden Cross is the first large precious metals mine to be both commissioned and closed in the æmodernÆ era in New Zealand. This paper discusses the life cycle of the Golden Cross mine, with emphasis on the closure process and post closure management.   The closure process has generally been very well managed, and successful, but in spite of that some on-going issues remain unresolved. Nearly nine years after the end of mining the mine owners are still actively managing the site, with no immediate end to that in sight.   The site has been described as atypical, due to the identification of a deep seated landslide below the tailings and waste rock storage facilities. However that should not be given too much emphasis when addressing the overall closure and post-closure management issues, which could well apply to other existing and future mine sites in New Zealand.   The Golden Cross can provide valuable lessons for other miners, and the issues arising at this site should be watched closely by the industry as a whole.

Jan 1, 2006

Introduction The mine winder is an essential element in the mining of ore in deep level mines and therefore requires a high degree of reliability to avoid interruption of production. Failure of any component on a winder may also be dangerous and expensive to repair. The larger the failure the larger the stoppage. The failure of a winder drum is the ultimate catastrophe, not only because of the cost of replacement, but also because of the lead time in procuring a new drum. Today these types of failure are not as common but many failures have occurred in the past and even today many an old winder is con- sidered for a new and often more arduous duty. As far back as the turn of the century a lot of information had been gathered to try and clear up the complexities of the multi- layering effect of coiling rope under tension onto a drum. Before comparing results obtained by various researchers the nature of the pressure distribution between rope and drum due to multi-layering will be discussed briefly.

Jan 1, 1987

In Australia, current production of rare earth element (REE) minerals, monazite and xenotime, occurs as by-product from titanium-enriched placers and beach sands. Undeveloped REE resources are associated with carbonatites, alkaline igneous rocks, pegmatites, phosphorites, cemented fluvial sandstones, and uranium mineralisations. The REE are held within a range of minerals including silicates, phosphates, a1uminophosphates, carbonates, and oxides. The development of these REE resources may require new processing and extraction methods. The distribution of REE in the currently mined ore minerals, monazite and bastnaesite, does not match that requested by the market. Exploration for new REE resources should be focused on ores with more marketable REE distributions, particularly with heavy REE, neodymium, samarium, europium and yttrium enrichments. Such ores occur within alkaline igneous rocks, in laterites overlying carbonatites and alkaline igneous rocks, and in placers derived from low-grade regional and contact metamorphic sediments. Lateritic REE deposits may be easily and economically mined by shovel in open pits and are unlikely to require extensive crushing and milling. In addition, lateritic REE clay deposits may be processed by simple hydrometallurgicaltreatment mehtods.

Jan 1, 1991

In November 1992, the Internal Revenue Commission (IRC) was formed from the rperggr of the Papua New Guinea Taxation Of- fice (PNGTO) and the Bureau of Customs, and now has the re- sponsibility for the administration of direct and indirect taxes on a national basis in Papua New Guinea (PNG). Since that date we have undertaken many initiatives to make the new organisation more efficient and responsive to clients' needs. Income Tax The mining industry is catered for, in respect of income tax, un- der a separate taxation regime within the Income Tax Act (ITA), Division 10, as well as some general provisions within that Act as may be applicable. Division 10 is itself broken up into subdi- visions to cover the different types of mining leases, namely Spe- cial Mining Leases (SMLs) and Mining Leases (MLs), and peri- ods of time during which those sub-divisions apply. Ring Fencing Income tax assessed on the mining industry, with the exception of Mining Leases (these will be explained later), has a project basis of assessment, that is, each project is assessed separately as if the taxable income of the taxpayer from operations attributable to the project was the only assessable income derived by that taxpayer. This is often referred to as "ring fencing". This is an important point to consider because losses from unsuccessful projects cannot be set off against income from those that are suc- cessful, except in very limited specific circumstances, such as where an unsuccessful exploration licence is cancelled or surren- dered. The project basis of assessment applies to both resident and non-resident companies. A relaxation in the 'ring fence' provisions was applied from 1st January 1995, where ten percent of exploration expenditure, in- curred in areas outside of Special Mining Leases and Petroleum Development Licences in a particular year of income, can be claimed as an outright deduction which is limited to ten percent of the tax otherwise payable in that year. This was introduced to encourage exploration in PNG.

Jan 1, 1997

By H von Blottnitz, A C. Keith

The influence of the life of a mine extends beyond its immediate vicinity both in geographic and temporal terms. Decisions around mine approvals are generally made based on economics, for the mine owner and immediate environmental and social impacts by governments and communities. The value from life-of-mine planning can also be viewed in a holistic frame across the entire value chain from mine to product user. This research examines the Carmichael Coal Mine in light of the holistic benefits and impacts along its value chain from the mine to relieving the lot of energy poor in India.CITATION:Keith, A C and von Blottnitz, H, 2016. Can Australian coal alleviate energy poverty in India – a case study, in Proceedings Life-of-Mine 2016 Conference , pp 52–56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

New Zealand Steel Limited is nearing completion of the environmental reporting and planning procedures for its proposed fivefold expansion to steelmaking at Glenbrook, and supporting mining operations at Waikato North Head. A report on the proposal to transport concentrate from the mining operations to Glenbrook has also been prepared and is awaiting release. This paper draws from these events, and by discussing some of the problems encountered, gives some guidelines for the preparation of an Environmental Impact Report.

Jan 1, 1981

Universities have had a long history in the education of geology graduates, Analysis of this history reveals a record of success, as judged on a world basis. However there have been significant changes in the last 20 years that have impacted on the ability of universities to continue to provide their traditional style of geology education. These changes have increased in the last 10 years. In the teaching side, there has been a change in expectations. Additionally the increasing workload decreases the value of each academic to perform the tasks needed by the new education. In the area of research, the funds provided have continued to decline, in both real and absolute terms, and it is now necessary for universities to seek out funds to pay for their postgraduate research. Additionally, the universities have slipped into the error of what cahn only be termed "academic incest", and research student mobility has decreased to an undesirable level, stifling initiative and new ideas in a number of cases, The only solution is for Government monies to be "directed" - ie that the postgraduate student must leave his or her original university in order to receifve the research stipend/scholarship. On the government front, the government and its agencies have not adequately analysed and recognised the need for the redirection of education and research funds into the needy areas of science and technology, especially those that related to the minerals area.

Jan 1, 1986

Transport technology has produced social changes since the invention of the wheel five millenna ago when man was freed from the need to expend large amounts of energy to move goods and people. Further impetus came with the Industrial Revolution when mechanical power producing devices were applied to land and-water transport. This leap, together with the application to air transport has caused enormous social changes in our way of life. The state of technological advancement of transport modes has dictated to a large degree the develop- ment of Australia and Papua New Guinea. It is suggested that we should not make advances for technology's sake but examine the real needs of the users of transport and ensure that the un- necessary costs are not incurred. The transporting techniques for the ore, waste and slurries used by Bougainville Copper in Papua New Guinea are, in general, quite conven- tional but the scale of operations and the location has modified some modes. in particular the soft' overburden and concentrates were slurried for trans- port and the lack of experience in humid climates restricted the choice of the mine haulage truck. The near future of the transport. industry is seen as an expansion in equipment sizes but the suggestion is made that we need to examine more than the economic and technical aspects; it is necessary for the social con- sequences of our actions to bear examination by outside opinion

Jan 1, 1973

By J Rutter, J du Plessis, er, M Scott, D Alex

It is generally acknowledged that bulk ore sorting is an attractive prospect for the mining industry. However, uncertainties relating to the operational performance of sensor technologies, the grade heterogeneity present in analysed material and the physical separation performance of the coupled system complicate the evaluation and deployment of bulk ore sorting strategies at operations. To assist in the quantification of these uncertainties, the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) and Anglo American have implemented a systematic methodology to evaluate the deployment of sensor technologies for bulk ore sorting. This methodology was implemented at a bulk ore sorting demonstration plant using penetrative prompt gamma neutron activation analysis (PGNAA) and surface x-ray fluorescence (XRF) measurements of base metals, as a proxy for precious metals, at Mogalakwena PGE Mine. The methodology comprises of three phases. The initial phase involves the preliminary investigation of sensor technologies and analysis to reduce identified risks prior to commissioning of the bulk ore sorting plant. The second phase executes a series of experiments to prove the sensing technologies in the operational environment and provide confidence the sensors can drive separation. The final phase demonstrates the production scale bulk ore sorting performance of the plant and validates its performance by campaign of the sorted products at the processing plant. Throughout the operational deployment and evaluation of bulk ore sorting at Mogalakwena, several key lessons were learned. These learnings relate to the calibration requirements of the sensor technologies, the application of surface vs penetrative sensor techniques and the preservation of grade heterogeneity delivered to the sensors. This paper presents the methodology used, and lessons learned, in the operational deployment and evaluation of PGNAA and XRF sensors for bulk ore sorting at Mogalakwena PGE Mine.

Nov 10, 2020

By S Garnes, W Austerberry, S Fraser

Despite significant investment in safety in the mining industry (mostly focused on processes and systems), many companies are unable to sustain and further improve their performance resulting in continued workplace incidents. The problem persists despite the best efforts of companies and allocation of resources to achieve Zero Harm. A DSS survey in 2019 found that two out of five companies that cannot manage risks and face disaster, leave the market within five years. All safety/risk management systems have the common steps of risk identification, prioritisation, design of controls consistent with risk tolerance, and verification of implementation/operability of controls. This is then complimented with improvement to one or more of the above elements through learnings obtained from incident investigations. In principle, the above process should work to reduce risks to, and keeping them at, a risk level consistent with risk tolerance in the organisation.

May 5, 2022

By Q Zhou, H Nordberg, W Wang-Geissler

Efficiently controlling foam/froth within mineral processing continues to pose a challenge to the mining sector. The foaming characteristics of aqueous solutions for two-phase systems of air/liquid are well-studied with theories and mechanisms proposed to describe and predict foam formation and stability. The types and structures of reagents that either promote or prevent foaming/froth formation and stability are well-defined in these studies and practiced across various applications. Three-phase systems of air/liquid/solid, such as froth from mineral slurries, however, pose a challenge with the presence of a large quantity of relatively fine mineral particles. Theories and mechanisms that rationalise the effects of chemical additives as a defoamer or foaming agent in aqueous can be applied as a general rule, but do not provide the most effective solution for mineral slurry systems. Silicone-based defoamers, particularly their O/W emulsions, have been widely and successfully used at various stages of mineral processing to efficiently control the mineral slurry foaming properties. However, their foaming control ability could be significantly impacted by different processing aids used during the upstream process. In a zinc-rich mineral system, a silicone-based defoamer starts losing the properties necessary to effectively control foaming in the leaching circuit when throughput is increased. In this study, the synergistic defoaming/anti-foaming effects from surfactants and silicone-based defoamers are discussed to effectively control foaming/froth in the zinc leaching circuit, even with lower total defoamer dosage. Improvements during mineral processing can also lead to a cleaner mineral grade by reducing waste.

Aug 24, 2022

By G Balog, T Ormerod, D Sidea

Carrapateena is a copper-gold sub level caving operation located in the Gawler Craton, South Australia. One of Australia’s largest undeveloped copper deposits, the project will be a 4.25 Mtpa underground operation, with an estimated mine life of 20 years (OZ Minerals, 2017). First concentrate production was achieved in December 2019, within the Iron Ore Copper Gold (IOCG) hematite breccia complex. The Carrapateena orebody is overlain by 500 m of barren sediments of the Stuart Shelf, which hosts two aquifers. The cover sequence is dominated by shales, quartzites and sandstones in order of thickness. The cover sequence presented challenges to the mine ventilation system as a result of highly variable rock strengths. On this basis, the site developed the first vent rise, Vent Rise 5 (VR5), earlier than required as a means to test the empirical stability assessment. Assessment for VR5 was completed in 2017, with the mine yet to develop through much of the cover sequence. Due to the geotechnical data available at the time, it was anticipated that break out would occur within the vent rise walls as a function of the low strength Woomera shales. VR5 was developed to 4.5 mᴓ in late 2018. The timing of the VR5 development enabled the site technical team to calibrate empirical stability factors for the assessment of future vent rises. At the time of writing, four additional vent rises have been successfully developed to a diameter of 5.5 m. No significant overbreak has been observed within any of the vent rises. This paper is intended for geotechnical practitioners designing large-diameter vent rises in geological environments similar to the Stuart Shelf where a similar approach to vent rise design may be warranted.

Mar 15, 2021

By Denisov GA

Conventional processes for disintegration of ores are characterised by low selectivity and cause damage to the components of their structure. It affects their liberation and recovery which are connected also with the inevitable formation of extreme fines. In the world practice recently came into view 4 trend to grinding of materials within a thick layer (in a bed layer), which provides a substantial selectivity of liberation, for example, of kimberlite. The degree of diamond preservation in the final product is highly increased. However, this method causes a considerable overgrinding of material. A new method of intralayer vibro-impulse breaking of materials providing an easily adjusted force acting at the layer and timely removal of product size grains from the grinding chamber has been developed in Russia.

Jan 1, 1993