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By F Minz, P Lamberg, A Mwanga, C Lund, C Wanhainen, M Amiri Parian, J Rosenkranz

A geometallurgical model is currently built in two different ways. The first and the most common way relies on geometallurgical testing, where a large number of samples are analysed for metallurgical response using small-scale laboratory tests, eg Davis tube testing. The second, mineralogical approach focuses on collecting mineralogical information over the orebody and building the metallurgical model based on mineralogy. At Lules University of Technology, Sweden, the latter method has been adopted and taken further in four ongoing PhD studies. The geological model gives modal composition by the help of element-to-mineral conversion and Rietveld X-ray diffraction. Texturally, the orebody is divided into different archetypes, and liberation measurements for each of them are carried out in processing fineness using IncaMineral, a SEM-based technique. The grindability and liberation spectrum of any given geological unit (sample, ore block, domain) are extrapolated from the archetypes. The process model is taken into a liberation level by mass balancing selected metallurgical tests using the particle tracking technique. The approach is general and can be applied to any type of ores. Examples of ongoing studies on iron and massive sulfide ores are given.CITATION:Lamberg, P, Rosenkranz, J, Wanhainen, C, Lund, C, Minz, F, Mwanga, A and Amiri Parian, M, 2013. Building a geometallurgical model in iron ores using a mineralogical approach with liberation data, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 317-324 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Neville Rockhouse

This paper examines the interrelationship of conducting full risk assessments in the context of the coal mining industry and under the framework of the Health's Safety in Employment Act 1992. In the context of Occupational Health's Safety, Risk Management is a holistic management process that can be used by individuals working in all organisations and from all industries. The Australian New Zealand Standard 4360: 2004 defines a Risk as being; The chance of something happening that will have an impact on objectives. This definition is followed by several notes that include: a risk is often specified in terms of an event or circumstance and the consequences that may flow from it, risk is measured in terms of a combination of the consequences of an event and their likelihood, and risk may have a positive or negative impact. For the purposes of this paper, the above definition will be adopted. This paper examines the newly expanded approach of the fully documented risk management process in the New Zealand coal mining industry. This is done in the context of the coal mining regulations but more importantly by using the framework of the Health & Safety in Employment Act 1992. This legislation under Section 6 requires all employers to, Take all Practicable Steps to prevent harm coming to employees while at work and to others who might be at or in the vicinity of a workplace. When the term 'all practicable steps' is studied, one can clearly see that such steps should be the same steps taken that a prudent and reasonable person would have taken given the same type of circumstance. Due to the fact that in New Zealand parliament made statutes is administered by a Government Department, means that their breaches will be heard before a judge in the District Court. Under the Westminster System of Justice, a basic dictum of that court in matters relating the occupational health and safety is that a breach needs to be satisfied to a specific standard. That standard is, 'Beyond a reasonable Doubt'. One of the primary benefits of adopting a proactive approach to risk management is that if the industry were to adopt similar approaches, then this mythology could be seen as an industry standard. As such, the approach carries the same status in a court of law, as that of an Approved Code of Practice.

Jan 1, 2007

By Roe P, Lowell A

This paper outlines software development and design work carried out by Mincom Pty Ltd in collaboration with Capricorn Coal Management (CAPCOAL) for computer based design of rehabilitated strip mine landforms at German Creek Mine. Current developments and future application areas for this software are also discussed in relation to other mines in Central Queensland. The development program was initiated in response to statutory requirements placed on mining companies in 1990 to produce a five year Plan of Operations which was to include a contour plan of the final rehabilitated mine landform at the end of the five year planning period. This plan was to be submitted to the Department of Resource Industries (DRI) by 1 December 1990. Due to the limited time given to prepare the plan, a work program was formulated in collaboration with Mincom Pty Ltd to develop suitable software to carry out the design work and provide the required plans and quantities. The software had to include computer based methods to allow design of the proposed landform in line with the rehabilitation strategy adopted by CAPCOAL at the time.

Jan 1, 1991

As the surrounding environment continues to change and evolve, mine managers face a changing climate of expectations. TodayÆs mine managers must juggle competing pressures to deliver sound social, environmental and economic results. Leadership is a fundamental tool for the effective mine manager. Whilst mine managers require solid technical and operational skills, importantly the manager must be able to engage a workforce, build and retain employees and seize opportunity for growth and development when presented. An important tool for engaging employees in the business at Rio Tinto Aluminium is the business improvement programme. At Rio Tinto AluminiumÆs Weipa mine, the business improvement methodology Six Sigma is used to deliver measurable, sustainable outcomes for the business. The next step in Rio Tinto AluminiumÆs improvement journey is to implement Lean Manufacturing at all managed operations. The operating environment for mine managers continuously evolves and effective mine managers must be flexible and adaptive to meet challenges. Governance and regulation constantly change in an environment of commodity cycles and finite resources. This increases pressure on the economic return achieved by the operation. As such, effective mine managers must be aware of and manage the operating environment û the broader, issues-based environment not just the immediate day-to-day responsibility of mine managing. This includes delivering on safety, community and environmental priorities. At Rio Tinto Aluminium, part of managing the business is via investment in the area of social partnerships to engage employees and the broader community in Rio Tinto AluminiumÆs commitment to sustainability. The Future Reef partnership entered with the Great Barrier Reef Research Foundation in 2005 forms an important part of Rio Tinto AluminiumÆs climate change strategy. This four-year, A$1 million investment funds programmes looking at the effect of ocean acidification on the Great Barrier Reef. The partnership is a unique example of industry and science working together on an area of mutual and national concern. Modern mine managers require a broad set of skills to effectively deliver outcomes. TodayÆs mine managers must make innovative and courageous responses to determine todayÆs strategy for tomorrowÆs future.

Jan 1, 2006

By H Ramandi, H Masoumi, I Canbulat, B Hebblewhite, J Oh, S Saydam, W Timms, S Mo

This paper reviews the floor heave mechanisms in underground coal mine roadways. Previous studies have reported three main failure mechanisms: bearing capacity failure, buckling and swelling. The buckling failure has been observed where immediate floor strata are relatively strong and thinly bedded. On the contrary, the weak floor strata have been associated with both the bearing capacity failure and swelling mechanisms. The bearing capacity floor failures are likely to induce other types of instability such as pillar punching, tensile failure of pillar, roof fall and subsidence as well as floor heave. Despite a considerable amount of research, predicting the magnitude, location and timing of floor deformation is challenging with current state of knowledge. CITATION:Mo, S, Ramandi, H, Oh, J, Masoumi, H, Timms, W, Canbulat, I, Hebblewhite, B and Saydam, S, 2018. A review of floor heave mechanisms in underground coal mine roadways, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 196–206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Thornton D, Esterle J, La Rosa D

Control of blast fragmentation has a significant impact on coal mine profitability. Two approaches for the characterisation of coal blastability, particularly in terms of fines, are presented. Both approaches were implemented for the predictio

Jan 1, 1998

Traditionally, the Lead Lode at Broken Hill has been represented on presentation plans, cross sections and diagrams in scientific papers as a solid black mass, around which the more 'interesting' and 'structurally useful', wall rocks appear to wrap. Structural analysis of the Broken Hill orebodies has usually turned to these wall rocks to determine the structural history of the mineralisation.This tendency to represent the orebody as a massive single entity is incorrect and the aim of this paper is to illustrate that sulphide orebodies (in this case Lead Lode), are a dynamic part of the mine stratigraphy. They can preserve a great deal of useful structural information that can be recorded with detailed internal mapping.Three main categories of ore type are recognised in Lead Lode; Stratiform ores, Mobilised ores and Metasomatically altered ore. The ore types in these categories occupy or have formed in distinct structural and stratigraphic positions and have clearly recognisable inter-relationships.

Jan 1, 1993

By S Nowosad, O Langefeld

The mining industry has undergone a profound and transformative shift in recent years, driven by the rapid advancement of emerging technologies such as automation, digitalisation, and electrification. These technological innovations have not only revolutionised operational efficiency and productivity but have also introduced an imperative need for new and innovative approaches to conducting mining activities. Specifically, the mines of the future face a new series of complex challenges when planning and developing greenfield or brownfield mining projects in the 21st century. These challenges include greater operational depths, higher seismicity levels, higher rock temperatures, increased environmental constraints and sustainability requirements, a higher degree of interoperability, lack of skilled workforce, and the need for sustainable and eco-friendly mining practices. Consequently, there is an essential need to formulate novel strategies and robust planning methodologies that re-evaluate how mines are planned, executed, and managed, from the early exploration stages to the post-mining era and the consequent uses of mine sites. This research focuses on identifying the factors influencing the implementation of modern technologies, such as autonomous machinery in mining operations, and their impact on mining method selection and longterm mine planning. The findings underscore a crucial need for a paradigm shift in how mines are planned and developed, going beyond mining method selection, which primarily focuses on geological and economic factors, and must evolve to incorporate the multifaceted implications of modern mining operations.

Sep 1, 2024

Exploration for uranium in Australia commenced only during the 1940s, but in this short period has been very successful as one third of the world's low cost uranium reserves have been discovered in Australia. Total uranium exploration expenditure in Australia up to the end of 1983 was $A(1983) 554 million; this discovered 20 potentially economic deposits and official reserves of 560 000 tonnes of uranium oxide at an average cost of $1 per kg of U 0 . An exponential 8 eserves indicates distribution of uranium r that there could be 54 undiscovered uranium deposits in Australia, each with reserves of 20 000 tonnes U308 or more, in addition to smaller deposits. Using a constant uranium price of $A(1983) 79 per kg, no deposit is economic at a grade below 0.12 per cent U 08 or with reserves of less than 3 000 tonnes. Selecting deposits with reserves of 5 000 tonnes U 0g or more as prime exploration targets, only 39 per cent of discoveries will yield a real internal rate of return (IRR) of 10 per cent or more. After committing a minimum exploration budget of $10 million to this search, an explorer has one chance between 7 and 12 of discovering a deposit that will repay the exploration investment.

Jan 1, 1984

The Devonian Mount Morgan gold-copper deposit was situated on the western margin of the Calliope Volcanic Are assemblage, in the northern New England Orogen. Recorded production from commencement of mining in 1882 to mine closure in 1989 stand

Jan 1, 1994

By Ghose AK

Design and selection of support systems for longwall faces call for in-depth know- ledge of strata mechanics and in particular of strata-support interactions. The paper presents the results of field investigations and analysis of a difficult-to-cave roof using powered supports under a massive dolerite sill in Central India using a state- of-the-art datalogger system. The mechanised long wall face was equipped with 4/680 tons chockshields operated on the IFS mode using a 300 KW DERD shearer. The datalogger system was capable of storing data simulta- neously in 32 channels. The paper describes the monitoring system and the monitoring programme. The system provided useful information on support behaviour, build- up of leg pressures and face convergence during an intense dynamic periodic weighting phenomenon which destroyed the integrity of almost half of the face supports. At this point, the face had advanced by about 197 metres from the barrier. The paper outlines a post-mortem analysis of this dynamic event and provides a critical evaluation of the data collected for understanding strata support interaction and the behaviour of the massive sill in the overburden.

Jan 1, 1992

Standards in the public reporting of resources and reserves in Australia have dramatically improved since the implementation of the Australasian Code for Reporting of Mineral Resources and Ore Reserves (The JORC Code) in 1989. Whilst the JORC Code states clearly that Mineral Resources and Ore Reserves are imprecise calculations and should be treated as estimates, there is strong evidence that many people regard them as fact, including some accountants, directors, auditors and investors. Mineral Resources and Ore Reserves are key inputs in the valuation of a mining company and the determination of financial performance. Geological knowledge is the foundation upon which Mineral Resources, Ore Reserves and investment decisions are made, however this information carries with it substantial uncertainty. Case studies and company reports have established that errors derived from inadequate geological inputs have led to reduced profitability in operating mines and in extreme cases the premature closure of mine operations. Whilst there are many causes of mine closure and reduced profitability, including commodity prices and exchange rates, the cumulative effect of all geological uncertainty contributes significantly to the erosion of the credibility of mining within the investment community. There are a number of methods used to characterise and model uncertainty in Mineral Resource and Ore Reserve estimation. Empirical mining indexes, sensitivity analyses, Monte Carlo simulations and Conditional simulations are used to identify and estimate geological uncertainty, notably the quantification of uncertainty in grade and tonnage estimates. These techniques have not generally been applied to estimating geological uncertainty associated with key Ore Reserve inputs such as appropriate mining technique, equipment selection, production rate, mining dilution, stability requirements, materials handling, metallurgical processing, product quality and waste storage. New software tools are needed to model the entire mining process with all its geological and other interdependencies, enabling all uncertainties to be separately identified and estimated. By its very nature, mining involves the assumption of significant technical, financial, political, environmental and social risk. Success comes by understanding and managing these risks and consequently the mining industry will never choose to reduce the level of geological uncertainty to nil. The ultimate aim of improved identification and estimation of geological uncertainty is to quantify inputs into the Ore Reserve process, allowing a company to assess the risks and manage these accordingly. This approach is relevant to feasibility studies for new projects as well as life-of-mine planning through to the weekly schedule at existing mines.

Jan 1, 2003

By Hoberg H, Schneider FU

Flotation tests were conducted with galena, quartz and with synthetic mixtures of the two, in different ranges of grain size, and with different process parameter variants. Physico-chemical analyses were also carried out on surface energy and on xanthate adsorption on galena with different grain sizes. Reference will also be made to hydrodynamics, interfacial chemistry and the influence exerted by grain size in flotation.

Jan 1, 1993

Ulan Coal Mines Limited operates an underground and open cut mine near Mudgee in the Central West of NSW. The mines are part of a Joint Venture managed by Exxon Coal and Minerals Australia Limited (ECMAL). Currently all the mines output of over five million tonnes per annum is sold into the export market predominantly as a steaming product.

Jan 1, 1993

By Schonert K

The throughput of a HP-roller mill is determined by the acceleration of the feed material within acceleration zone and introduction into the compression zone. Both processes depend on the internal friction and the friction of the material on the roller surface which is influenced by the surface structure and adhering of material. The particle motion in the acceleration zone has been investigated with high speed videos showing the effect of the centrifugal force and the slip on the roller surface. The throughput is discussed in the term of the specific throughput which can be approximated by a linear function characterised by the throughput number and the throughput elasticity. The throughput number is a helpful measure for investigating the influence of the feed material and the surface structure. The experimental results give some guidance for chosing an optimum corrugation profile.

Jan 1, 1993

By Marton A

The Readymix Group have a Quarry Improvement Program - 'Building in Quality (BIQ) which has many parallels to the ICI Explosives' total quality management - 'Quality Improvement Program' (QIP). Both companies have for some time recognised that the 'do it right first time' principle means less wasted effort and materials, that efficiency breeds profitability and so actively promote the quality culture. To install the principles and generate the culture requires considerable commitment and effort from the top down and invariably spreads to the suppliers and sub-contractors. Understanding the component processes involved with the quarry operation, analysis of those processes and gaining a breakdown of the cost of non conformance then allows the astute quarry operator to make the necessary changes to improve the process to realise profits. This paper outlines the steps in such a process and the profitable outcomes of the commitment to continuous improvement at the Nickol Bay Quarry.

Jan 1, 1994

By Koppe J. C

This paper describes the methodology developed to establish a sequentia mining plan applied to a coal mine, using computers. Firstly, isocontou. maps were generated from the drill holes and outcrop description information, representing the thickness and depth of the rock formation: present in the mine site. The procedure relies on the repeated application of the cross validation techniques, until the standard deviation of thi estimation is reduced to a minimum.From this map the coal reserves of the two coal seams, the overburdet (separated in hard and soft material) and the interburden were calculated After that, the maps were transferred in digital files to AutoCAI software, where different mining plan simulations were performed. 7b ore evaluation in each case was done automatically, including tonnages volumes and stripping relations. The final mine configuration consider the economic aspects of the operation.

Jan 1, 1993

Most text books on rock blasting claim that the relationship between burden and borehole diameter is linear. The statistical calculation presented here with real values from one hundred open pit and underground mines indicates that the relationship is exponential. For underground mines the burdens are consistently lower than those for open pit mines because of higher ore densities, greater confinement in blasting, and finally greater demand for well fragmented rock. The results shown in this paper are recommended to be considered in basic teaching of rock blasting technique. The formulas can be used for a first rough estimation of practical burden and spacing. The formulas do not however give any information about the fragmentation. For that purpose it is necessary to use other formulas not described in this paper.

Jan 1, 1990

Legislation up to the early 1950s prevented the mechanical extraction of pillars. The mines operating at that time had formed extensive areas of pillars. When permission for the mechanical extraction was gazetted, conventional equipment was employed for pillar extraction and generally using hand mining systems. The mid-fifty's saw the of continuous miners. These machines eliminated the disadvantages of conventional equipment and the necessity for multiple working places. Some new layouts for panels emerged; however, actual extraction methods of pillars still followed closely that of hand mining. During the early sixty's the extraction of standing or new formed pillars was undertaken by the "open-end lift" or a "split and lift" method.

Jan 1, 1974

By D J. Williams

Tailings management is typically constrained by many factors that are taken as given. These include the tailings production rate that must be accommodated, the desire to deliver the tailings cheaply and easily as a slurry using centrifugal pumps, and a tailings footprint limited by the desire to minimise capital costs leading to a rapid tailings rate of rise and a low settled density. Other constraints include wall raises being delayed due to limited capital, inadequate tailings water and rainfall run-off management, and the net present value (NPV) approach to capital expenditure that puts off expenditure at the expense of performance. All of these constraints result in the tailings occupying much more volume than is necessary, being difficult to rehabilitate, and not being capable of supporting a beneficial post-mining land use or function. Ultimately, such constrained tailings storage facilities will assume very large dimensions, but each will typically be developed as a series of smaller storages that are filled rapidly and added to progressively. The optimal stage to efficiently recover process water is in the process plant, but this is limited by the desire to use centrifugal pumps rather than the more costly positive displacement pumps, which also require greater management of tailings deposition. Process water can also be recovered from the tailings storage facility (TSF) decant. Tailings water that is not recovered from the plant or the decant will be lost to entrainment within the tailings, seepage to the foundation or through the wall, or evaporation. However, tailings water is not always suitable for reuse in the plant, particularly when it becomes contaminated by the processing, and it may simply be stored on the TSF. This will exacerbate the seepage of contaminated water to the environment, and will limit the densification of the tailings that would otherwise occur due to desiccation of the tailings on exposure. If a larger tailings footprint were developed early, cycling of tailings deposition in thin lifts between a number of cells could occur, maintaining the dormant cells dry to enhance desiccation and densification, and ultimate rehabilitation. The end result would be a much reduced stored volume of tailings, the potential for upstream raising, and ease of rehabilitation to a high level. The higher initial capital cost would be overtaken by reduced ongoing capital, operating and closure costs.CITATION:Williams, D J, ?2014. An alternative whole-of-life approach to tailings management, in Proceedings Life-of-Mine 2014 , pp 285–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014