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By K Evtiminova, G Jobson, M Nolte, S Meik

Chelopech Mining EAD (CMEAD) is a wholly owned subsidiary of Dundee Precious Metals Inc (DPM) and operates the Chelopech underground mine and processing facility located in Bulgaria. The final product sold is a flotation concentrate containing copper minerals with associated gold and silver. The increase in production from 0.6 to 1.0 Mt/a by 2009 occurred with the original (1975) secondary/tertiary crushing, and primary/secondary ball mill circuits. As part of the mine/mill upgrade project to 2.0 Mt/a, a new single stage semi-autogenous (SAG) mill and ancillary equipment was installed, replacing the original circuits, with commissioning occurring during the first half of 2011. Aspects of the design, commissioning and operation of the new comminution facility are the subjects of this paper.An extensive program of comminution characterisation test work was completed in 2004/2005, which indicated moderate hardness and competency characteristics. The characteristics were considered suitable for a range of comminution approaches which were assessed with respect to power requirements and capital and operating costs. Retention of the existing primary crushing facility, and installation of a new single stage SAG mill located within the existing mill building, was selected as the design for the expansion.An extended ramp-up schedule for the overall concentrator upgrade turned out to be necessary as the comminution and flotation circuits were completed prior to several downstream unit processes (concentrate filtration and tailings thickening), which were required to reach the design mill feed throughput rate on a sustainable basis. This resulted in the opportunity to gradually increase the SAG mill ball charge as necessary, to obtain the throughput corresponding to the various downstream processing constraints.A relatively fine cyclone overflow stream particle size distribution is a feature of the Chelopech comminution circuit that has not been fully overcome with increasing ball charge conditions. However, design throughput has been met even under the finer product size conditions and will be consistently achieved following the commissioning of two further process improvement projects scheduled for late 2012.CITATION:Jobson, G, Nolte, M, Evtiminova, K and Meik, S, 2012. The modernisation and upgrade of concentrator operations at the Chelopech Mine, Bulgaria - Design, installation and operation of the 250 tonnes per hour comminution circuit, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 325-332 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By Y Li, S Ramazan, E Topal

A mine waste dump progression plan can provide a clear outlook of the mining operation. To produce such an output requires detailed placement schedule of the mined material, including the volume (or tonnage) and the allocated dumping location. However, current practise mainly focuses on the ore production, over-simplifying the waste material scheduling. As a result, a rock dump is often treated as a single point in long-term planning, making it difficult to predict the waste dump progression pattern over the life-of-mine. Without such a guidance, it is almost impossible to carry out progressive rehabilitation on the waste rock dumps. The lack of dumping schedule could cause delay in development construction, ie tailing storage facility and run-of-mine pad. Other downstream effect due to the over-simplification is inaccurate estimation of required truck hours, which could have huge financial impact on the operation.In this paper, mixed integer programming (MIP) models of different objective functions, ie maximise truck productivity by minimising the overall haulage distance, minimise required truck deviation between adjacent years, and a hybrid between the two objectives, are utilised to generate the long-term optimum rock placement schedules under the criteria of satisfying site specific conditions. All three MIP models are implemented in a large scale open pit mine. The numerical solutions from the models forms three different rock placement schedules, based on which, the yearly truck requirements are easily calculated and compared. The graphical results show the three corresponding waste dump progression patterns over the life-of-mine, providing the optimised long-term forecast of the operation.CITATION:Li, Y, Topal, E and Ramazan, S, 2014. Optimising the long-term mine waste dump progression and truck hour schedule in a large-scale open pit mine using mixed integer programming, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 335–344 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Sato S, Kawaguchi T

The granulation and bed-permeability of sinter raw materials depend on interactions between the properties of various iron ores and water. The properties of individual iron ores are controlled by their particle size distribu- tion and surface characteristics, which can be described by representative particle size and wettability, respectively. Added water may be absorbed, affect granulation or lower bed permeability. These effects were experimentally studied as a function of properties of the iron ores. A mathematical model was developed in order to calculate the granulated particle size and permeability using the known blend of sinter raw materials. The calculated results were in good agreement with the observed values.

Jan 1, 1980

By M Orunesu Preiata

The Odysseus Project is part of the high-grade Cosmos Nickel Complex that lies 30 km north of Leinster. The Odysseus definitive feasibility study (DFS) was approved by the Western Areas’ board in October 2018. Early works commenced in January 2019 with rehabilitation of the existing underground infrastructure. In June 2022 Western Areas was acquired by IGO Ltd. The project is now well advanced to meet its target of first concentrate. The project included the construction of a haulage shaft. The design of the hoisting equipment and the shaft barrel evolved from the initial DFS design stage to the final execution, as the data were made available from the initial investigation to the data gathered during execution (although this did not change from its initial concept). The design philosophy for the haulage shaft incorporated, from the beginning a multidisciplinary approach with inputs from three main areas involved in such projects, namely excavation techniques, geotechnical assessments, and infrastructure construction. This interaction is a fundamental component for the success of such a critical project. In fact, each of these three areas influences each other in a cyclical manner, triggering a continuous review of the project inputs and outputs, while maintaining the original project goals: the design of an infrastructure able to deliver the desired throughput. The throughput dictates the infrastructure that needs to be built, which in turn controls the size of the shaft. The key assumption applied to this is that the rock mass can accommodate the excavation void, and the excavation technique with its tolerances and limits that ultimately need to be verified back with the initial assumptions used for the infrastructure design. The aim of the paper is to present a case study of the experience gained with the Odysseus hoisting shaft and to propose a possible logic path for similar projects elsewhere.

Mar 29, 2023

By G T. Jemwa, F Rousseau, F J. Wolfaardt, J A. M Rademan, P W. Smit

Mining companies are increasingly faced with the challenge of reducing operating costs while maximising throughput and profitability. At the same time, the grade and quality of treated ores are becoming poorer and more variable, resulting in suboptimal process performance.It is now widely accepted that strategies to drive operational goals must revolve around improving plant availability, reliability and process efficiency. In particular, progress in plant automation and control systems has seen a trend towards unified frameworks for control and optimisation of mineral processing plants. These frameworks seek to seamlessly integrate different roles and tasks involved in process operations - IT, automation, plant maintenance and operations. An integrated solution framework for reducing process variability, increasing process efficiencies and maximising plant availability and reliability is discussed within the context of a typical milling circuit. The framework exploits a real-time analysis ægapÆ evident in production operations that prevents timeous identification of equipment and process failures. This is achieved by leveraging predictive analytics for equipment health monitoring, control loop monitoring and advanced regulatory control solutions towards enhanced process performance, improved asset management and regulatory compliance. The framework provides for early and actionable warnings on equipment and process degradation using real-time operational data.Resolving these problems can potentially avoid unplanned downtimes, process instabilities and other operational surprises, thus ensuring optimal plant throughput and optimal process behaviour for improved recoveries. Integrating control systems and plant automation with advanced analytics to analyse and optimise processes enables operations to achieve reductions in the variability of key process parameters. In addition, early detection of equipment malfunction or suboptimal process conditions leads to improved equipment availability and reliability. Ultimately, these operational gains reflect in profitability because of plant throughput and recovery gains. These benefits are demonstrated using data from a South African gold mining operation, where such an integrated asset and process health monitoring framework for process optimisation has been implemented.CITATION:Jemwa, G T, Wolfaardt, F J, Smit, P W, Rademan, J A M and Rousseau, F, 2013. Towards an integrated framework for asset and process health monitoring and optimisation on a milling circuit, in Proceedings World Gold 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

This paper outlines mining practice in the South Alligator valley between 1954 and 1964. The valley is situated in the Northern Territory 130 miles south east of Darwin and trends north west. The centrally located El Sherana camp is 219 miles by road from Darwin via Pine Creek on the Stuart Highway. 64 miles of gravelled road with low level bridges and culverts which were completed in 1959, connect Pine Creek with El Sherana. This road is often impassable during severe wet season conditions. Earliest recorded production was during the years 1956-57 from the El Sherana and Palette miles, by shallow open cut and cut and fill stoping from small shafts. 4600 tons of high grade ore was processed by hand sorting of massive pitchblende followed by gravity concentra- tion. At the same time 627 tons of ore was won from a small open cut at Sliesbeck 35 miles SE of El Sherana. The second and most important phase of production was to fill two small contracts with the United Kingdom Atomic Energy Authority (U.K.A.E.A.) totalling 700 tons of U 08. About 144,000 tons of ore was mined from widely separated smal' orebodies and mining practice varied from small open cuts to gloryholes, open stoping and cut and fill stoping. In some orebodies a combination of several methods was employed to complete production. Final deliveries were made to the U.K.A.E.A. In 1964.

Jan 1, 1968

There are a number of mineral processing operations which produce at some point a stream of hot particulates. At today's energy prices it becomes important to recover the energy held in the hot particulates. Sometimes it is convenient to use gas, e.g. in air pre- heating, and this will be appropriate in some circumstances. There are cases where it would be very useful if energy in the hot processed particles could be exchanged to the cold feed solids. This can be achieved within appropriate limitations by countercurrent heat exchangers comprised of parallel channels which contain, alternately, fluidized solids of 'hot' and 'cold' streams respectively. A pilot- plant has been built. Some calculations relating to industrial application will be Presented.

Jan 1, 1981

By F Carrick, W A. Ellis, D R. Mulligan, S I. FitzGibbon

"One of the major environmental impacts of mining is the destruction of habitat. The koala (Phascolarctos cinereus) is an iconic Australian marsupial that has been severely affected by land clearing and its decline is continuing. This has placed pressure upon mining companies and government agencies to ensure koalas are managed throughout the life-of-mines - from land clearing through to rehabilitation of post-mining landscapes. This paper reports on the æKoala VentureÆ research partnership between The University of Queensland and Rio Tinto. As part of the Koala Venture program we examined koala use of two types of restored environments: rehabilitated mined land (20 sites) natural regrowth forests (six sites), at Blair Athol Coal Mine in Central Queensland, Australia. Searches for koala scats revealed evidence of koalas in ten per cent of rehabilitated sites (2/20) and 33 per cent of natural regrowth sites (2/6). Two factors were identified as being of greatest importance in facilitating koala recolonisation of restored habitats. Firstly, all recolonised sites were located close to native forest occupied by koalas (mean 135 m ¦ 52). Proximity to source animals is considered crucial to recolonisation of suitably restored habitats. Secondly, three of the four recolonised sites were dominated by koala food trees, most of which were large enough to be utilised by koalas. Availability of suitably abundant food resources is, therefore, also considered crucial. The requirement for these two factors, in combination, is highlighted by the absence of koalas at several sites that contained abundant food trees, but that were distal to areas with source animals, and vice-versa.Our research demonstrates the enormous potential for restoration of wildlife habitat on post-mining lands, even for species with specific requirements such as the koala. Consideration of the ecological requirements of wildlife during rehabilitation planning is critical to enhancing the likelihood of recolonisation.CITATION:FitzGibbon, S I, Ellis, W A, Mulligan, D R and Carrick, F, 2012. Rehabilitating post-mining landscapes for wildlife - A case study from the Koala Venture research program in Central Queensland, in Proceedings Life-of-Mine 2012, pp 319-324 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

By K M. Cook, D Clark

Fatality prevention and zero harm are key focus areas for resource companies. However, they remain an ongoing challenge for high hazard industries, including the mining sector. As one example the latest International Council on Mining and Metals (ICMM) Safety Performance Report shows that, while there is generally a declining fatality trend since the organisation commenced publishing data in 2012, there were still 33 fatalities across member companies in 2022 (ICMM, 2023b). Every fatal incident brings significant pain and suffering to the colleagues, friends and family of those involved, however the failures and causal factors leading to each incident are frequently very familiar to people working in the industry, particularly those tasked with managing risk and safety. In the words of Dame Judith Hackitt, Grenfell Tower Fire Investigator, ‘there are no new accidents – just different people making the same mistakes because they haven’t learned’ (Hackitt, 2022). The recurring themes in terms of the nature of fatal hazards and their associated causes across the mining sector show that, despite improvements evidenced by the favourable declining fatality trends over the long-term (in general and outside of catastrophic multiple fatality events), changes are required to achieve fatality elimination and the aspiration of zero harm. This extended abstract and the accompanying presentation apply a mining frame of reference to the idea that there are no new accidents, examining how this applies within the industry and why the lessons from past failures are not always well understood or applied to prevent the reoccurrence of material unwanted events. Many contemporary mining and resources organisations have extensive internal incident history data and a wide variety of information on fatality incidents is publicly available, including the annual ICMM Safety Performance Report. This extended abstract and the accompanying presentation explore how this existing data can be used effectively to learn from the past and proposes practical ideas regarding strategies for successful knowledge transfer to the workforce as a key component of preventing history repeating and improving safety performance across the industry. As noted by ICMM, ‘sharing lessons from failure is vital to improving health and safety, but it’s not enough’ (ICMM, 2023a).

Apr 16, 2024

Three separate and unconfined aquifers occur in the Hilton area, named relative to position in relation to ore horizons: Footwall Aquifer in the east; Ore-Zone Aquifer within the ore-bearing Urquhart Shales; and the Hangingwall Aquifer in the west.It is the on-going strategy it Hilton to drain the Ore-Zone Aquifer which occupies structurally- and sulphide-controlled leached zones in the steeply west dipping strata. The aquifer affects considerable ore reserves to 480 m below the surface. Dewatering began in 1976, and is essentially completed to 4 level (240 m below surface). Dewatering efforts are now based on 8 level (480 m below surface).

Jan 1, 1993

The concentrated efforts now being directed towards the development and application of monitoring and control techniques have now resulted in their widespread use in UK mines together with evidence of benefits resulting from their application. There is little doubt that the longwall method of producing deep mined coal will continue but will be made more reliable and efficient with the aid of control technology. The major fields of research and development work are concerned with planning and design of mines and mining equipment; management and engineering information; and automation of coalface, tunnelling and transport systems. The principal achievements now in widespread use are: the standard computer system MINOS, widely applied to mine transport, coalfaces and mine environment; extensive use of machine condition monitoring leading to condition-based maintenance; underground automation of conveyor systems and guidance systems for ranging drum shearers and boom-type roadheaders are being widely introduced.

Jan 1, 1985

By Q Fan

The steelmaking desulfurisation plays an important role in coal-based steelmaking route of blast furnace and BOF converter within the flow sheet of BF-deS-BOF. With the advent of H2-based ironmaking and steelmaking process, the transition flow sheet of DRI-Smelter-BOF has been assessed and developed by the steelmaking industry. What is the role of deS in H2-based route of DRI-smelter-BOF? This paper will present the influence of sulfur-containing iron ore on steelmaking desulfurisation and the leading role of EAF-smelter played in H2-based steelmaking route. The sulfur contents of iron ore vary considerably around the world and lower-grade iron ores with high sulfur are likely to be used for H2-based route, a considerable amount of sulfur that comes from DRI will report to the melt of EAF-smelter and the operating conditions of EAF-smelter also impact the sulfur content of the hot melt for steelmaking deS. The EAF-smelter of H2-based route is the focus of the steelmaking industry at moment, unfortunately, an industrial-scale EAF-smelter has been the missing link of the flow sheet of DRI-Smelter-deS-BOF, despite similar EAF-smelters being used for various applications of Fe-Ti and Fe-Ni processes. The latest progress is that several pilot-scale and industrial-scale EAF-smelters with reducing capability are planned for construction within next several years and low-grade Australia iron ores are certainly to be employed as basic feedstocks for H2-based route of DRI-Smelter-deS-BOF.

Sep 18, 2023

By S Graskoski, S Craig, C Myburgh

Too often in mine planning, maximising revenue-generating material takes precedence over minimising costs. The ability to target both revenue and cost optimisation enables mine plans to fulfil corporate objectives of targeting maximal project net present value (NPV). The state of current mining costs and increasing government regulations in Australia are forcing many mine planners to pay closer attention to cost minimisation. Dumping waste material, which ultimately forms waste landforms, represents a large cost to mining operations. A general mine, with a waste to ore strip ration of 6:1, allocates approximately 32 per cent of total mining costs to waste haulage alone (Gregory, 2003).Most scheduling packages do not dynamically build economic or minimal cost dumps as part of the scheduling process. In most cases, waste dumps are built after a mining schedule has been defined. Automated software is now available which dynamically schedules the pit and waste dumps together. The overall shape of the waste dump is therefore dictated by minimum cost or minimum haulage hours.The purpose of this paper is to compare dynamic pit and waste schedules to traditional methods which apply haulage estimations after defining the mining schedule. This paper includes a case study on the large open pit operation at Tropicana Gold Mine, a joint venture between AngloGold Ashanti Australia Ltd (70 per cent) and Independence Group NL (30 per cent). The operation will focus on mining three large open pits over a 13-year mining life. A total of 397 Mt of waste is mined and directed to multiple destinations including waste dumps, the run-of-mine (ROM) pad and tailings storage facility (TSF) perimeter.Due to these complexities, management of the haulage fleet, especially during the critical period of operation readiness and start-up, is essential. Critical infrastructure such as the TSF and ROM pad will need to be built early and these areas, as well as the sequential development of the waste dump, will need to be developed within the constraints of structured mining fleet build-up.This paper investigates the influences of haulage estimation accuracy and compares traditional approaches for waste planning to automated approaches using EVORELUTIONÖ.CITATION:Graskoski, S, Craig, S and Myburgh, C, 2013. Dynamic pit and waste dump schedule optimisation at Tropicana Gold Mine, in Proceedings World Gold 2013 , pp 121-128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By S A. Ravishankar, W Perez

Flotation is one of the main concentration processes to purify kaolin clay via the removal of naturally occurring impurity minerals containing Ti and Fe. Currently, there are two types of collector chemistries used in the industry to float coloured impurity minerals. These are traditional tall oil fatty acids (TOFA) and specialty hydroxamate (AHX) based collectors. AHX based collectors have long been known to be the most selective collectors to float Ti and Fe based coloured impurity minerals (CIMs) as compared to TOFA based systems. AHX based collectors provide, not only improved selectivity and simplified process, but also more importantly, make it possible to treat certain kaolin resources that do not respond to standard TOFA systems. However, the relatively higher cost of straight AHX collectors has restricted broader application of these collectors in kaolin clay and other oxide flotation applications for a long time. Recent technological advancements, in both making and formulating AHX products more economically, increased the usage of these collectors in kaolin applications. Modified AHX products offer more economical alternatives and process options to provide high purity kaolin clay products for specialty applications based on cost-performance criteria. In this paper, the flotation performance of a series of newly developed AHX formulations is provided along with the characteristics of AHX flotation in general. In addition, flotation performance of earlier AHX collectors is provided based on published literature as background data.

Jan 1, 2005

By Laas JJ, Spearing AJS

Considering the capital outlay, running costs and inherent difficulties of backfilling operations at depth the benefits need to be clearly established, quantified and then exploited. Expansion of Vaal Reefs Exploration and Mining Company towards even deeper, highly faulted ground, and the process of establishing codes of practice for the management of rockfalls and rockbursts, required that a sound support strategy be formulated. This paper describes the derivation of an overall backfilling strategy on Vaal Reefs. Use was made of experience gained over some 12 years with backfilling. Numerical modelling was used to estimate potential benefits of backfilling the deepest mining areas still to be extracted. In exploiting a probably unique opportunity, two contiguous mining areas bounded by the same major geological structures, were compared. One was extensively backfilled and the other not at all. Shaft sinking through a backfilled stope added another dimension to the database. Backfilling was introduced in 1985 and several potential spin-offs were expected. These included improved local strata control for fall of ground and rockburst conditions, regional benefits in rock mass stability and mine ventilation optimisation.

Jan 1, 1998

By Mould GR

Gas drainage has been practiced for many years mainly for safety reasons in various countries in Europe, in the U.S.A., the U.K. and Japan. Legislation has been developed to control the production, transport- ation and utilisation of methane and associated gases. Gas drainage is now being carried out at some Australian Collieries, but as this is a new venture little specific legislation is available. This paper briefly describes the drainage methods and legislation applied overseas, gives a brief history of gas drainage in N.S.W. and indicates the deficiencies of the present legislation. It outlines the approach to new legislation which will deal comprehensively with gas drainage operations and utilisation in New South Wales.

Jan 1, 1982

By J Pan, Q H. Li, D Q. Zhu, C C. Yang, X Wang, Z Q. Guo

Al2O3 in natural iron ores generally occurs in goethite, kaolinite, gibbsite, hematite and iron carbonate. When the content of alumina in sinter increases from 1.11 per cent to 3.50 per cent, the reducibility of sinter decreases with the addition of four different types of alumina. When gibbsite and kaolinite are added, the low temperature reduction disintegration (RDI+3.15 mm) of sinter increases with the increase of Al2O3 content in the range of 1.5 per cent to 3.5 per cent. Furthermore, when adding pure reagent alumina, the increase of Al2O3 content in the range of 1.5 per cent to 3.0 per cent will increase the RDI+3.15 mm of sinter. The addition of ferric oxide–alumina spinel with the Al2O3 content in the range of 1.5 per cent to 2.5 per cent, also increases the RDI+ 3.15 mm of sinter. The influence difference is results from the change of the mineral composition and microstructure of sinter because of the occurrence state of Al2O3. Under the condition that Al2O3 content of sinter is 2 per cent, the porosity of sinter with kaolinite is 37.26 per cent, and the shape is irregular. When gibbsite and ferric oxide–alumina spinel are added, the porosity of sinter is about 16 per cent, and the pores are round. When pure reagent alumina is added, the porosity of sinter is 17.49 per cent, and the pores are regular and small. When kaolinite, gibbsite and ferric oxide–alumina spinel are added, platy calcium ferrite is mainly formed in the sinter, and some of it is columnar calcium ferrite. On the other hand, when pure reagent alumina is added, in addition to platy columnar calcium ferrite, acicular calcium ferrite is also formed in the sinter.

Nov 8, 2021

Four data sets are required to put constraints on the tectonic evolution of the southern rim of the Pacific Ocean basinI . data bearing on the dispersal of the major Gondwanaland continental fragments and the birth of the Southern Ocean,2. data bearing on the interaction of the Pacific Ocean basin lithosphere with the South American, Antarctic, and Australasian continental masses,3. data bearing on.the evolution of the Scotia Sea floor, and 4. data bearing on the evolution of the various continents, microcontinents. and volcanic arcs.

Jan 1, 1990

By L Eriksson, D Penn, J Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are, in most cases, developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, the company has placed emphasis on accuracy in the drilling process and documenting what has been drilled. By applying state of the art technology to the common automation platform, developed for the surface drilling market, major steps in improving overall drilling productivity and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the companyÆs surface drilling products.CITATION:Appelgren, J, Eriksson, E and Penn, D, 2012. Rotary drilling automation increasing operator productivity and drilling quality, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 13-18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By Ramani R. V

There are many important physical phenomena in mine ventilation which involve transient mass and heat transfer processes. These processes have been modeled using differential equations often solved with close form solution. Within the last two decades, many numerical schemes have been devised to solve these mass-transfer problems. Much of this effort has focused on variants of the finite element and finite difference methods. In this paper, the solution of mass transfer models in mine ventilation by finite difference technique is discussed. Specifically, the computational effort and the accuracy of the solution are presented.

Jan 1, 1988