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Coal exports are forecast to grow strongly, so that coal is likely to remain very important to Australia for the foreseeable future. However there is no sign that prices or profitability will rise of their own accord. Therefore the intense squeeze on costs will continue for the foreseeable future. This will mean lower manning, more outsourcing and probably an increasing rate of company attrition. As well, the political pressure from the greenhouse debate is only going to intensify and the pressure on the Federal Government after Kyoto is likely to be irresistible.

Jan 1, 1998

By D W. Airey

Frictional rock bolts are widely used because of their low cost. However, they have a thin wall section that makes them prone to corrosion, and they cannot be relied on to provide long-term ground support. It is difficult to assess the capacity after the bolts have been installed as they can only be pulled out if this has been allowed for during insertion. The questions of how long can the rock bolts function effectively and the effectiveness of various surface coatings, which can have significant cost implications are, investigated in this study.A series of accelerated corrosion tests have been performed on frictional rock bolts. The rock bolts, typically 900 mm long, have been inserted into concrete cylinders produced using a styrofoam insert to create the hole for the bolt insertion. Strata rock bolts with four surface coatings have been tested: uncoated black steel, galvanised, enduro (plastic coated) and coated with a proprietary aluminium/zinc alloy. Tests have been performed on two diameters of bolts. Following insertion of the bolts, the concrete cylinders were placed in a large drum filled with saltwater and current was applied to accelerate the corrosion process. The rock bolts were then extracted at various times after the commencement of corrosion. Comparison of the insertion and extraction resistances shows that corrosion initially increases the bolt resistance and that substantial section loss is required for the bolt resistance to drop significantly.CITATION:Airey, D W, 2014. Laboratory corrosion tests of frictional rock bolts, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 257–262 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

The Snap Lake Phase I project initiated a subsampling campaign on the material (kimberlite/metavolcanic/granite) mined and treated for diamonds. The campaign was aimed at determining the optimum subsampling program to subsample the feed to the bulk sample plant (BSP) for the duration of a sampling campaign. This paper describes the application of GyÆs formula for determining the subsample size and other good sampling practices to determine this subsampling campaign. Three main issues are discussed: the use of a hammer sampler to sample off a moving conveyor and the practical experiment to determine the optimum subsampling program; bias introduced by laboratory equipment including two sizes rotary splitters; and variability of the feed material to the BSP over time.

Jan 1, 2005

By A J. Moore

The Australian Coal Association Research Program (ACARP) funded project, No C14057, entitled æEffect of Blasting on InfrastructureÆ, has been carried out with the objectives of providing methodologies for the assessment of the strength of infrastructure types and the establishment of responsible and realistic limits. Personnel from Melbourne, Newcastle and Swinburne Universities and Terrock Consulting Engineers conducted the project. Infrastructure types including: conveyors; power transmission towers; wooden power poles; electrical substations; pipelines, bridges; public access roads and underground workings have been investigated by both field studies and structural analysis. Railways, underground telecom cables, dams and industrial buildings have been reviewed using general structural analysis. This paper has been prepared for the mining industry to provide a progress report on the project.

Jan 1, 2007

The United StatesÆ reporting standard for the mining industry for securities purposes is contained in the Security and Exchange CommissionÆs Industry Guide 7. It defines proven and probable Reserves using its own definitions, and prohibits the disclosure of quantitative estimates, for all mineralisation other than those two Reserve categories (though disclosure of Measured and Indicated Resources as quantitative mineralised material estimates is now informally allowed). Similarly, it restricts disclosure of value estimates to Reserves only, which SEC policy generally requires to be on an historic cost accounting basis. The SEC does not maintain a formal Competent or Qualified Person policy. In March 1999, the US-based Society of Mining, Metallurgy and Exploration (SME) released an update of its 1991 guidelines for definitions to be used in reporting of Mineral Resources, Reserves and Exploration Information, closely abiding by the 1997 CMMI recommendations. However, without SEC recognition, reporting under the SME and CMMI definitions is effectively barred for US companies. The SEC intends to adopt the International Financial Reporting Standards (IFRS) of the International Accounting Standards Board (IASB). This will occur within just a few years, when the convergence project for development of the IFRS has reached a satisfactory point. The US is the largest financial supporter and participator in IASB. The Extractive Industries Standard of the IFRS will likely terminate Industry Guide 7. However, the effect of this international replacement will likely be equally restrictive. This could possibly neutralise the benefit of a CMMI-based global reporting standard. SME, the US society encompassing the widest range of mining industry professionals, does not have a Code of Ethics. It has no mechanism for requiring members to abide by a professional standard. SME is presently looking into possible solutions for this deficiency. US-based professional societies that do have a binding Code of Ethics, generally cater to a single profession, and are not just mining industry related. The American Institute of Professional Geologists (AIPG) and the American Institute of Minerals Appraisers (AIMA) are examples. The SME is considering creating a subsidiary body with an enforceable Code of Ethics. To support a CMMI-based global reporting standard, competent persons will need to work across international borders. A standardised mechanism for qualifying and registering competent persons will be needed. National rules and laws must allow competent persons to easily enter countries to perform their work. State issued licenses are increasingly required for much of the work performed in the US mining industry by engineers, geologists and minerals appraisers (valuers). Such licenses are not required by the SEC for Reserve reporting in the US, may not be required for valuation of mineral properties under certain circumstances, and except for real property valuer licenses, they generally do not have a binding code of conduct. However, state licensing of professionals forms a substantial and increasing barrier to interstate trade in professional services, and can be a prohibitive barrier to professionals from outside the US. Any rationalisation of this confusing patchwork of regulations confronting US minerals industry practitioners will only occur as part of larger, national change, hopefully aimed at compliance with international standards and protocols. The US does not have a valuation standard aimed specifically at the mining industry. The Uniform Standards of Professional Appraisal Practice, the national valuation standards, often must be applied to mineral property valuation, but contains no specific instructions for minerals. The author has campaigned against development of minerals valuation standards proposed by US minerals institutes. Instead he encourages the mining industry worldwide to place its support behind the initiative of the International Valuation Standards Committee (IVSC) to include an extractive industries section in its International Valuation Standards (IVS). This should provide a global set of valuation standards for the mining and petroleum industry within two years. This addition to IVS will provide essential valuation standards reference support for the extractive industries financial reporting standard of the International Accounting Standards Board. The IVS has achieved a high level of acceptance in the developed and lesser developed countries of the world. It provides a comprehensive framework of Generally Accepted Valuation Principles for the valuation profession internationally, for valuation of all property or asset types. IVSC is effectively a sister organisation to IASB. The IASBÆs International Financial Reporting Standards (IFRS), previously known as the International Accounting Standards (IAS), reference and quote IVS in some instructions for determination of fair value. IVSC is a non-governmental organisation (NGO) member of the United Nations and maintains liaison with many important international economic, accounting and financial agencies, such as the OECD, IMF and WTO.

Jan 1, 2002

The writer had the pleasure of several months' laboratory tests on a metallurgical process for copper ores devised by Mr. W. H. Corbould, Consulting Engineer, North Queensland. Mr. Corbould's research work in this direction commenced somesix years ago, and he eventually succeeded in obtaining a good extraction of copper and a resulting solution practically free from iron and other impurities. The commercial operation of the process was investigated and special machines with novel features were designed. OUTLINE OF THE PROCESS.The process described in detail in the following pages, required for successful application that the ores contain at least the minimum ratio of sulphur to copper, consistent with the production of sulphadising roasting conditions.

Jan 1, 1921

By R Lurf, C Weber

In the frame of this paper a holistic dynamic process model approach is presented in order to introduce operational and technical excellence in drilling and blasting. Both on a macro and micro level the single process parts of drilling and blasting are outlined and their interaction is explained. The use of this approach for closing the gap between process planning and process implementation is explained and an example of the value generated is given.

Jan 1, 2007

The rapid growth of world civilisation will have a significant impact on the way humans live in the future. As the global population increases and more countries demand a higher standard of living, the world must provide more food and greater energy and mineral resources to sustain this growth. The difficulty of doing this is compounded by three broad trends: the conversion of agricultural land to development uses; the increasing urbanisation of the world's population; and growing concern for the maintenance and improvement of the environment, especially regarding global warming and the impact of population growth. Underground space utilisation offers opportunities for helping address these trends.

Jan 1, 1993

By Purvis A. H, Greenwood-Smith R, Sowerby B. D

A nuclear technique for the determination of copper and nickel in bulk samples and drill core has been developed at Lucas Heights andfield-tested at Mount Isa. The technique, which is highly specific to the element being measured, utilises the gamma-ray resonance scallering process.A bulk mineral analyser was installed in mid-1976 for the routine assay of copper in bulk samples and drill cores, and remained in operation until late 1981. The operation of the analyser over this five-year period is reviewed with particular emphasis on reliability, accuracy and principal usage.The main application of this analyser was in stope planning and design whereby several thousand drill-core and Wall-chip samples were analysed. It was also used as an aid to underground grade control of stopes where ore dilution by supporting barren backfill was a problem.

Jan 1, 1984

By Mansor A. N

Results are reported for the computer simulation of heap leaching of mixed copper oxide and sulphide ores. They resemble those obtained from testwork in terms of a substantial peak in the copper concentration of the pregnant solution, an initial period when no copper emerges and a lengthy period towards the end when the copper concentration and the daily increment in copper recovery are low. The simulation can be used to forecast process results before any column or similar testwork is performed. Potential applications of the simulation to process design, operating strategy and optimisation are discussed. Three modes of operation are identified that correspond to different performance patterns and dependencies on ore and process variables. The relative merits of different operating strategies for approaching the ideal performance are being investigated. For process design and development purposes, the simulation may be used with a limited testwork programme to achieve significant savings in time and resources.

Jan 1, 1989

By C Mroczek, B Mitchell

Perilya Broken Hill, from its inception, has budgeted for more than 2.0 million tonnes per year from the Southern Operations. This tonnage was planned to come from in excess of 100 stopes per year in a remnant mining environment with numerous mined voids and consequent mining challenges. To mine an average of two stopes per week requires patience, flexibility and detailed knowledge to best manage the potential risks and hazards. The evolution of the Perilya Broken Hill Mine Planning Process has necessitated the establishment of a process to identify and manage these risks during the planning stage in a reliable but efficient manner. This process is to ensure that vital steps for each stope are not missed, and that each personÆs work can be tracked by other members of the team. This paper outlines the planning process from resource to stope closure.

Jan 1, 2005

By I Kolomaznik

Each technological process can be reduced on the transport networks, and namely on the parametric networks and the non-parametric ones. The parametric networks are created by the piping, electrical cables or channels. The non-parametric network is created by the ways, suspended grooves, trackages and also by the belt conveyors or other conveyors for continuous material transport. If we reduce the technological process on transport networks, then, by the creation of these networks models and their mutual interconnection we obtain the model of the whole technological process. The model can be understood as the universal one, without exaggeration, because it is valid for any technological process. However, for us the mining production process is important what represents the mining and transport of raw materials under the support of the ensuring system. In this contribution one of the first attempt is described, and namely how to connect the parametric network which has been already worked out very properly with the non-parametric network what is presented in this contribution by the transport line of belt conveyors.

Jan 1, 2003

By F Mavroudis, M Gaastra

Due to the increasing demand for resources worldwide, efficient utilisation of raw material deposits and recycling technologies become more and more important. Growing industrial nations and increased living standards require a large raw material supply. Hereby responsible handling of existent primary and secondary raw materials is indispensable. By utilising state-of-the-art technologies resources are extracted, recovered and recycled more efficiently which increases sustainability. Hereby sensor technologies combined with intelligent data processing systems in particular provide a considerable research area. Innovative sensor technologies are already implemented during recognition of material-specific characteristics, during elemental recognition as well as during machine control. They are applied to attain increased automation levels of mining machineries, higher recoveries during mining and processing as well as higher recoveries. To be able to face the increased demand for sensor technologies and the integration into raw material industries, an interdisciplinary association of three RWTH Aachen University Institutes has been founded. The association has expertise on increasing productivity and capacity utilisations by automating mining and recovering processes by sensor technologies. Due to the utilisation of sensor systems, materials and structures can now be detected and elementary analysed on a real-time scale. The developed and enhanced techniques are the key for any ambition of autonomous plants and machineries. This paper gives an overview on the regarded sensor technologies for material recognition, machine automation and mineral processing. The authors present concepts based on extensive laboratory and field studies of successful implementation and application the technologies considering special mining conditions. Overall three applications are described to demonstrate the potential of sensor technologies for autonomous and sustainable mining: real-time analysis: recognition of elementary compounds during extraction processes; multi-sensor system EiControlPlus: designed for automation of longwall shearers by complete detection of the machineÆs environment; and sensor-based sorting: applied in recycling and mineralÆs industries.

Sep 26, 2011

By McBride N

Location The Boddington Gold Mine (BGM) is located approximately 120 km south east of Perth, Western Australia. (Figure 1). Located within the picturesque Darling Ranges, the land was previously used for forestry activities prior to mining commencing in mid-1987. Mineralisation is hosted within deeply weathered felsic and intermediate intrusions and volcanic rocks of the Saddleback Greenstone Belt.

Jan 1, 1995

By P D. Franzmann, D J. Readett, J Peterse

A better connection between laboratory- and pilot-scale test results, and heap bioleaching performance can be achieved by generating reliable information on the fundamental microbial, chemical and physical processes that occur in heaps and incorporating this information into a comprehensive and robust model. More efficient heap bioleaching, particularly of chalcopyrite, has the potential to add value to the mining industry as well as deliver attractive environmental and social benefits to the communities within which those companies operate.The results of fundamental chemical and microbiological studies of the leaching mechanism, the temperature dependence of chalcopyrite bioleaching, and the optimisation of leaching conditions are described with examples from full-scale heaps. The development and application of a number of novel techniques and tools has assisted our understanding of heap subprocesses mineralogy, hydrology, chemistry and microbiology. The heap bioleaching model HeapSim, which embodies a large number of effects not previously accounted for in other models, continues to be refined and has been applied successfully to the study of several heap bioleach systems.

Jan 1, 2004

Rock bolting and rock-bolting systems depend for success on attention to a number of simple techniques. Failure to appreciate this fact can lead to disappointing results. Careful study of rock characteristics and placement methods can allow a change to highly successful rock bolt per- formance. A number of examples are quoted to illustrate the sig- nificant improvement in results which can be achieved by use of the most suitable combination of characteristics.

Jan 1, 1971

By Klenowski

Rational design of layouts for longwall operations is greatly facilitated by use of an accurate and economical method for predicting stresses and displacements. The displacement discontinuity method (a form of boundary element method) is based on replacing actual excavation geometries by thin slits of the same plan area. This approach allows three-dimensional stress- analysis at a fraction of the cost of alternative methods. The analyses can be readily performed on economical microcomputers, putting the analysis capability within the reach of mine-site personnel. This paper describes investigations associated with the German Creek Central Colliery, the first longwall operation in Queensland's Bowen Basin. The material properties used in the model, in particular the rock mass and goaf properties, have been 'tuned' to fit stress measurements obtained during extraction of the first and second longwall panels at the mine. The study shows that model predictions based on suitably scaled anisotropic rock strata properties are in good agreement with the stress measurements made to date. This model predicts average chain pillar loads significantly higher than predicted by models based on United Kingdom conditions. A working chain pillar design method is proposed using average pillar loads predicted by the numerical model and ultimate strength characteristics given by Bieniawski's formula.

Jan 1, 1988

By Jones BH

Discovery of the Vera-Nancy deposit in late-1995 followed 12 years of active exploration in and around the Pajingo Epithermal System, an andesite hosted veinfield covering an area of 150 square kilometres at the northern end of the Devono-Carboniferous Drummond Basin in North Queensland. Early exploration targeted open-pittable resources in the numerous auriferous veins and it was not until 1994 that exploration focus shifted to drilling to depths below about 100 metres from surface, which resulted in the Vera-Nancy discovery. That deeper drilling process is still at a very early stage of coverage of the epithermal system as a whole and substantial potential exists for additional discoveries.Drill-out of Vera-Nancy has to-date established a gold resource in excess of 1.4 million ounces. Mine development is proceeding via a twin decline system with first stoped production scheduled for August 1997.

Jan 1, 1997

By Richardson G. W, Yap L. C

Friction rock stabilisers (FRS) are the most common steel-based ground reinforcement used in underground mines in Western Australia. As with any other steel-based product used in underground mines they are susceptible to corrosion, particularly under aggressive minewater and mineral conditions. Because of their thin-wall tubular construction and large surface area, the potential damage resulting from corrosion is considered to be more severe for this type of reinforcement than for other forms of reinforcement made of solid steel bars. Because of the obvious safety problems which may result from corrosion, both mine operators and regulators have raised concerns regarding the long-term effectiveness of FRS installed in underground mines in Western Australia. Although corrosion has been recognised as an important safety issue, the controls of corrosion in varied underground mining environments has not been well understood. To improve the understanding of the corrosion behaviour of FRS, the Department of Minerals and Energy has initiated a research project focused on the mechanisms and extent of corrosion attacks, and their influence on the effectiveness of the reinforcement. This paper describes the research project and presents the interim results achieved To-date.

Jan 1, 1995

Iron formation-hosted iron ore deposits account for the majority of current world iron ore production and consist of three classes: unenriched primary iron formation with typically 25 to 45 wt per cent Fe; martite-goethite ore formed by supergene processes, with abundant hydrous iron oxides containing 60 to 63 wt per cent Fe; and high-grade hematite ores thought to be of hypogene or metamorphic origin overprinted by subsequent supergene enrichment with 60 to 68 wt per cent Fe.Individual iron ore deposits range from a few millions of tonnes to over two billion tonnes at >64 wt per cent Fe, although most are within the range of 200 to 500 Mt. In the Hamersley Province of Western Australia, martite-goethite ores are largely developed in the Marra Mamba Iron Formation, although high (>0.08 per cent P) phosphorous mineralisation is also well developed in the stratigraphically higher Brockman Iron Formation. Whilst the vast majority of high-grade microplaty hematite ore is best developed in the Brockman Iron Formation, this paper provides the first textural evidence of locally significant microplaty hematite mineralisation in the Nammuldi Member of the Marra Mamba Iron Formation, in the Chichester Ranges at the Christmas Creek, Cloud Break and Mount Nicholas prospects. Petrographic studies have identified a high-grade Fe texture composed of nanometre scale plates of hematite in mineralised sections of primary microplaty hematite deposits in the Pilbara and elsewhere, well below the normal depth of weathering or dehydration. The population of nanometre to micrometre scale hematite plates is interpreted to represent various stages of nucleation, crystallisation and progressive growth of hematite from the primary ore-forming fluid in areas that were once iron-rich carbonates or silicates in the BIF.

Jan 1, 2005