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A New Technology of Applying SLon-2500 Magnetic Separator to Recover Iron Concentrate from Abandoned Tails

Sep 13, 2010

Comparison of Discretised Population Balance (DPB) and Finite Element Method (FEM) Methodologies for Modelling Batch Gibbsite Precipitation

Sep 13, 2010

Mining is both a high risk and a long term business. This is dramatically illustrated by the fact that, on average, the explorer will expend over $30 million in a ten year period for each significant economic discovery. The time required to complete the exploration process is one of the most substantial commitments made by any mining company. For example the time lag between the implementation of an exploration programme and an economic discovery is variously estimated to take two to ten years. The ore definition phase following discovery currently takes between two and five years while subsequent mine development may take one to two years in easy situations and up to 8 in difficult environments. In most countries the critical path through the early stages is determined largely by technical considerations but in almost all countries the path through the later phases is dictated by the plethora of permits, licences and community involvement steps.

Jan 1, 1982

This paper reviews recent positive developments in Europe on the regulation of gold mining. However, it also examines the problem that while gold projects may be bankable and technically and environmental defensible, the odds tend to be stacked against granting of an environmental permit. The historic background to this situation is examined and current developments and initiatives are critically analysed. Standards and benchmarks for the industry have been established across the community and these have a strong influence in European Union accession (and aspiring) states as well. While this is welcome in regard to improving environmental performance, it also represents a significant milestone with mining (and particularly gold mining) now æon the mapÆ as a legitimate enterprise, a situation that was patently not the case prior to 2003. At the project level, very frequently, the difficult biophysical problems are addressed and satisfactorily dealt with according to the new regulations, but still there are problems regards trust and acceptance that underpin a æsocial licenceÆ. What goes wrong and how can companies deal with the social/environmental issues that lead to entrenched views and concerns, irrespective of any amount of demonstration of good practice and corporate social responsibility? What is the role of the non-governmental organisation (NGO) and are they as accountable and responsible as they should be? The findings presented draw upon recent experience with the environmental permitting of projects in Spain, Greece, Romania, Bulgaria and Serbia on behalf of Australian, Canadian and British companies as well as international funding institutions.

Jan 1, 2007

By D R. Carr

The installation of the Flotation Capacity Project flow sheet in the copper concentrator at Mount Isa Mines Limited has recently been completed. The project involved increasing the flotation capacity with Wemco tank cells and Jameson cells as well as changing the copper cleaner circuit layout. The engineering design and construction for the brownfield expansion had significant involvement from operational, maintenance and technical personnel adopting the same approach as the highly successful George Fisher project in the Lead/Zinc Concentrator at MIM. The involvement of people familiar with the concentrator allowed for smooth integration of the changes into an operating concentrator with minimal downtime. Detailed circuit analysis over many years identified opportunities for improvements in the flotation circuit for both grade and recovery. This paper describes the program of work that led to the Copper Concentrator Flotation Capacity Project, and the implementation of the circuit expansion and flow sheet changes that resulted in an overall improvement in the circuit recovery.

Jan 1, 2003

Fine Coal Evaluation by Gravity Methods

Sep 13, 2010

Application of the Anaconda Simplified Work Index for Multiple Test Sizes Vale uses Bond Work Index measurements extensively in a number of applications. The Bond Work Index is usually a good parameter for checking scale up procedures when sizing ball mills, as well as the basis for variability analysis whenever drill core data is available. It is typical to measure between 100 and 150 Bond Work Indexes, depending on the deposit characteristics. The Bond procedure is relatively complex and time costly. It also requires relatively large amounts of sample, which are very expensive to be obtained. The benefits of the Anaconda simplified procedure are: considerably smaller sample requirements and laboratory time. This makes it very much attractive at Vale's development centre, including geometallurgical mapping, operation efficiency control, mine to mill, etc. The Anaconda simplified procedure was implemented and evaluated at Vale's Development Centre using a number of ores and several samples of each ore totalling more than 190 measurements. The Anaconda simplified method was calibrated for several test sieves and a correlation for any test size was determined for Vale's test mill. The calibration was also extended for two sample top sizes. The relative error of the simplified procedure was found to be in the range of nine per cent which is within the expected error Bond standard procedure. The implementation of the Anaconda method at Vale's development center has been used with great success over the past years in several green field, brown field projects and operating plants.

Sep 13, 2010

A vital ingredient in ensuring that metals exploration companies, working in the developing countries of thePacific Rim, support the development of national geologists is making such a learning program cost-effective. There is a wide spectrum of learning needed in the development of these explorationists: the technical and conceptual skills to carry out exploration efficiently, the professional and managerial skills to apply the exploration in the work situation, the personal attributes required to manage their exploration effectively, and a company organisation that allows them to learn and use these skills and attributes.

Jan 1, 1995

There is a significant amount of historical mining and exploration information available. This information is often distributed throughout a number of reports or plans, available from a variety of sources, and in many differing formats. The ability to capture paper-based historical information in a modem digital format provides mining and exploration companies with valuable information that can be used in a number of ways; for example, reassessments of exploration or mining work previously undertaken, or used in conjunction with current exploration information.   The purpose of this paper is threefold. Firstly, to present the paper-based historical information; highlighting some of the problems encountered, solutions to those problems, and any assumptions used. Secondly, to present the historical data in digital format, and demonstrate the tools available to analyse geological and associated information, and finally, to illustrate some of the potential future applications of the information, including mining optimisation, mine design and scheduling.   The Glenorchy scheelite/gold prospect has been used as an example. Within the overall prospect two smaller areas were selected. The Mount McIntosh and surrounding areas, focuses on exploration and surface excavation information. The Mount Judah area (State and Kelly-Taylor workings) focuses on underground mining and exploration information.  

Jan 1, 2001

By W Valery, S Morrell

In the mining industry blasts are usually designed to fracture the in situ rock mass and prepare it for excavation and subsequent transport. The run of mine (ROM) fragmentation is considered good when it is fine enough and loose enough to ensure efficient digging and loading operations. Mining optimisation strategy is hence usually focussed on minimising total mining costs and maintaining these ROM fragmentation characteristics. Although this approach ensures an efficient mining operation it ignores the potential impact on crushing and grinding. Investigations by several researchers have shown that designing blasts to produce ROM fragmentation to optimise crushing and grinding performance enhances the overall efficiency and profitability (Eloranta, 1995; Kojovic et al, 1995; Bulow et al, 1998; Kanchibotla et al, 1998; Scott et al, 1998; Simkus and Dance, 1998). Field experimentation in this area is often found to be difficult because of high implementation costs and insufficient understanding about the effect of fragmentation at different stages in a comminution circuit. Modelling and simulation of blasting and comminution processes provide a more economic alternative to explore the impact of blast design changes on the down stream operations (Kanchibotla et al, 1998; Kojovic et al, 1998; Adam and Siddall, 1998; Bulow et al, 1998). However, the reliability of such simulations depends on:the ability of the models to reproduce the physical processes that take place; characterisation of rock mass in terms of its blastability and comminution characteristics; and in the case of blast modelling the ability to predict fines (-10 mm) has been found to be particularly important as this fraction has a significant effect on mill throughput.

Jan 1, 1999

By D J. Williams

The approach to the disposal and storage of mine tailings is slowly evolving. Tailings disposal has been based on minimising short-term capital and operating costs, with rehabilitation costs discounted by the application of a high discount factor in a net present value approach to accounting. This has led to the widespread adoption of surface tailings storage facilities (TSFs) to store slurried tailings delivered by robust and cheap centrifugal pumps and pipelines. Depending on the site climate, rate of rise of the tailings, nature of the tailings and the extent to which supernatant water is removed from the surface TSF, the tailings may or may not dewater, densify and gain strength. High rates of rise of dilute tailings to a facility used to store both tailings and supernatant water results in a wet, low-density, soft tailings deposit that not only occupies a large storage volume but also presents rehabilitation difficulties. A low tailings density results in high containment wall costs, very high rehabilitation costs and a low potential for future land use or ecological function. Overall, the cost of slurried tailings disposal, thought to be low, is actually high. However, low rates of rise, even of dilute tailings, in a dry climate with efficient supernatant water removal can produce a dewatered, high-density, stiff tailings deposit that may occupy a large footprint but to shallow depth that is relatively easy to rehabilitate. There are advantages in dewatering tailings in the processing plant to recover process water and chemicals, facilitate tailings disposal in a more solid form and facilitate rehabilitation. However, the cost of dewatering in-plant can be high, and the process water may not lend itself to reuse. There are also advantages in removing supernatant water to facilitate solar and wind drying of exposed tailings, although water is lost to evaporation and the dried tailings may best be harvested prior to inundation by fresh tailings or rainfall run-off. This paper discusses the background and trends towards the elimination of conventional surface slurried TSFs, with examples presented of the management of black coal and other tailings, including those that are clay mineral-rich.CITATION:Williams, D J, 2015. Towards the elimination of conventional surface slurried tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 11–24 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

Recovery of Pentlandite and Chalcopyrite from Tailings by Bi-Cyclone Powerful Flotation Column

Sep 13, 2010

By N Anderson

The world-class Golden Mile gold deposit in the Eastern Goldfields of Western Australia is part of the Kalgoorlie Consolidated Gold Mines (KCGM) operation, which is wholly owned by Northern Star Resources Limited. Current mining operations across the Golden Mile is dominated by the large Fimiston Open Pit, which is over 4 km long, 1 km wide and 600 m deep. It is part of a larger mineralised system that stretches over 8 km and includes the Mt Charlotte Underground Mine, which is also operated by KCGM, as well as numerous historical open pit and underground mines. This mineralised system has been continuously mined for over 125 years and is set to continue well into the future. The Golden Mile deposit is in the Norseman Wiluna Greenstone Belt which is made up of a series of mafic volcanic and sedimentary rocks that have been structurally deformed and intruded by granitic rocks. There are two main styles of mineralisation across the Golden Mile. Firstly, the Fimiston style, which consists of shear hosted Golden Mile lodes with abundant sulfides and tellurides and secondly, the Charlotte style that comprises younger stockwork veins. Fimiston style mineralisation is the primary style of mineralisation within the Fimiston Open Pit. Historically, in excess of 3500 m of underground development and over 755 stopes were mined prior to the consolidation of the area and the commencement of Fimiston Open Pit operation. Old underground workings, known as voids, are either empty or backfilled and extend to more than 1.2 km below surface. Although they are a routine part of mining operations at KCGM, voids pose a significant challenge for the geology team in terms of planning and executing exploration and grade control drilling, geological modelling, grade and tonnage estimation, drill and blast design and execution, marking up ore block designs, mining, and reconciliation. This paper will discuss the various challenges faced by the geology team due to the presence of voids, solutions used to overcome some of these challenges and the results of these activities.

Mar 22, 2022

In the context of sustainable development, the Minerals Council of Australia (2010) states that 'investments in minerals projects should be financially profitable, technically appropriate, environmentally sound and socially responsible'. In other words, the business of mining can only be sustained if these criteria are met.   Science and technology plays a major role in all four of these criteria. This paper will present the technology and innovation emerging from the Minerals Down Under National Research Flagship which brings together CSIRO and more than ten of Australia's leading universities to work with industry to drive efficiency, productivity and environmental performance. This work is required if the Australian minerals sector is to thrive and continue to deliver national benefit in the face of increased global competition, declining ore grades, depleting ore deposits, increasingly constrained national resources (land, energy, water and people) and changing societal expectations.   Science and technology to reduce emissions and water use, discover greenfields resources, enable deeper mining operations and transform mineral processing are described. Technology is presented as an enabler of sustainability: a means to this end but not as an end in its own right.

Jun 1, 2010

Following the Coalbrook Colliery disaster in 1960, Salamon and Munro (1967) established the well known empirical coal pillar strength formula in South Africa. This formula has prevented further violent multiple pillar failures. In 1996, a back analysis of the collapsed and uncollapsed cases in Australia led to the development of the Australian empirical coal pillar strength formulae. The original collapsed and uncollapsed coal pillar database of Salamon and Munro (1967) was updated in 2006. This study introduced various strength formulae for different coalfields and seams in South Africa through back analyses of collapsed and uncollapsed cases. Today, the resultant pillar strength formulae from these previous studies and the behaviour of coal pillars are mostly well understood and applied with confidence. However, it was assumed in the previous studies that the behaviour of pillars is not time dependent; therefore, the formulae established do not provide an associated time to failure of coal pillars. This paper attempts to evaluate the so called 'Geometrical Limits' concept to provide the Australian coal mining industry with a tool to assess the long-term behaviour of bord and pillar workings where the pillars are prone to failure due to spalling of ribs. In order to achieve this outcome, the principles of the safety factor concept and the probability of failure calculated using the coal pillar strength formulae have also been evaluated and practical design examples are presented in this paper.

Nov 25, 2010

By G J. Corbett, T M. Leach

A continued exploration programme has further defined the geology of the Tolukuma vein system, verified the resource indicated by Newmont, and identified potential for additional mineralisation. The resource at Tolukuma Hill, designated as zone C, is a mine recoverable 432,000 t at 18.1 g/t Au & 46 g/t Ag. Mining will be by a combination of open pit and underground at a rate of 100,000 t per annum. Processing will be by SAG mill, gravity circuit and CIL plant. A diatreme breccia, localised at an intersection of structures and a relationship of gold to base metal sulphides, are indicative of a strong porphyry association. Typical epithermal features such as crustiform banded quartz and quartz pseudomorphing platy calcite are also present and locally contain lesser gold mineralisation. Pre-existing dilatant structures have acted as a host to the ore fluids, resulting in the formation of the semi-continuous Tolukuma-Gulbadi veins over a 1100 m strike. A fluid flow model suggests that mineralizing fluids were sourced from a diatreme margin and migrated laterally along dilatant structures. Bonanza gold grades are interpreted to be derived through fluid quenching in the flexure between a hanging wall split, which hosts much of the Tolukuma Hill resource, and the feeder graben structure. Thus, the relationship between the pre-mineral structural geometry and fluid upflow at the margins of a diatreme breccia, controls the ore setting.

Jan 1, 1995

Research and Tests on Improving the Technology of Enrichment of the Copper-Molybdenum Ore

Sep 13, 2010

Study on the Interaction Mechanism of Flotation Reagents and Rare-Earths-Bearing Phosphate Ore

Sep 13, 2010

Optimisation of the Performance of Flotation Circuits Using a Genetic Algorithm Oriented by Process-Based Rules

Sep 13, 2010

The mercury, gold, silver, copper, lead and zinc values of soils over altered and mineralised rock were determined to establish the potential use of mercury as an indicator element in geochemical prospecting. The results are presented to show that mercury can be used successfully in prospecting for precious metal mineralization in the Thames-Waihi area.

Jan 1, 1979