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Industrial and telecommunications organizations around the world are now turning to optical fibres to satisfy their growing needs for data, voice and video communications and to solve transmission problems in noisy and hazardous environments. Already, coaxial cables have been made obsolete for intermediate and long distance applications and fibres are making in-roads on other copper cable and microwave system techniques.The idea of optical fibres is not new, but techniques to manufacture the high quality cable and components required have only recently been developed. Nonetheless, the technology is now advanced, reliable and mature, and costs are plummeting with increased production and market competition.The mining industry has benefited greatly from developments in electronics and communications over the years. Optical fibres are to have a further significant impact and the time is now right for the industry to begin to exploit the many advantages of this new medium. Applications include data transmission, long distance telecommunications, measurement and control systems, surveillance, computer networks, etc.This paper briefly describes the characteristics of optical fibres, current status of the technology, applications and possibilities for future development.

Jan 1, 1984

Nuclear power stations to be installed in Australia will be fuelled from Australian resources of raw materials.This will require the establishment of new manufacturing industries and the eventual expansion of established activities, especially in uranium mining and the preparation of precision metal products.This paper presents some predictions of the possible growth of nuclear power installations in Australia.These might amount to 4000 MWE by 1985 and 11,500 MWE by 1990 and towards the end of the century, about 50 per cent of new generating plant might be nuclear.Predictions are given of the demands for materials (uranium and zirconium) and fuel manufacturing services for four reactor systems which might be considered in the programme.The availability of raw materials and technical capability place Australia in a particularly good position to undertake the manufacture of nuclear fuel; in addition to satisfying the domestic demand we should actively seek export markets for these products.

Jan 1, 1971

By Alder KF

Nuclear power stations to be installed in Australia will be fuelled from Australian resources of raw materials. This will require the establishment of new manufacturing industries and the eventual expansion of established activities, especially in uranium mining and the preparation of precision metal products. This paper presents some predictions of the possible growth of nuclear power installations in Australia. These might amount to 4000 MWE by 1985 and 11,500 MWE by 1990 and towards the end of the century, about 50% of new generating plant might be nuclear. Predictions are given of the demands for materials (uranium and zirconium) and fuel manufacturing services for four reactor systems which might be considered in the programme. - The availability of raw materials and technical capability place Australia in a particularly good position to undertake the manufacture of nuclear fuel'; in addition to satisfying the domestic demand we should actively seek export markets for these products.

Jan 1, 1970

With the exhaustion of orebodies close to the main haulage shaft of the Emperor mine, an increased rate of development, aimed at earlier investigation of values disclosed by exploration drill holes has been attained with an overall reduction in unit costs.This paper describes the techniques used in rates of advance up to and exceeding 1,000 ft per 28-day period.

Jan 1, 1966

The JORC Code, which has been in existence as a Code incorporated in the listing rules of the Australian Stock Exchange and New Zealand Stock Exchange since 1989 and 1992 respectively, has been revised and will be re-released in 2003. This revision followed a call for submissions in December 2001, the publication of an exposure draft in late-2002 and an exposure period during which a large number of constructive comments were received. These comments were reviewed and a further exposure draft released as part of the current exposure draft of the ASX listing rules. It is anticipated that the final Code will be incorporated into the stock exchanges listing rules in late-2003. The 1999 JORC Code has been the standard on which other reporting Codes have been based, each of which has contained refinements. Three in particular, the Reporting Code from the United Kingdom/Ireland/Western Europe, the new Canadian Reporting standards and the SAMREC Code from South Africa, influenced JORC in the preparation of the 2003 JORC Code. Whilst there are differences between the 1999 Code and the 2003 Code, these changes are mainly in the guidelines. The Code definitions, which are largely in accord with agreed international definitions, remain substantially unchanged. The two main changes in the 2003 Code are the requirement for a Competent Person to be responsible for the documentation relating to the reporting of Exploration Results, and the introduction of æRecognised Overseas Professional OrganisationsÆ as overseas organisations to which Competent Persons may belong. Other changes include: clarification of the reporting of exploration targets or potential; the rearrangement of the diamond reporting clauses; the introduction of guidelines for the reporting of Industrial Minerals; modification of the coal clauses and recognition of the new Coal Guidelines; and the introduction of a guideline encouraging the discussion of relative accuracy and confidence in resource/reserve estimates. Other lesser changes to the Code are listed and discussed briefly. The release of the 2003 JORC Code maintains the standard set by JORC as a world leader in the development of mineral reporting Codes and their adoption by industry.

Jan 1, 2003

The consideration of environmental constraints and issues is a fundamental component of all stages of planning, development, operation and decommissioning mining and quarrying projects. Provision needs to be made at all stages for the cost of environmental components since it is of fundamental importance that they be recognised as an integral component of any project. This paper presents an approach to environmental costing, suggested levels for budgeting, and the cost benefits.

Jan 1, 1990

Understanding multiphase particulate systems is essential for the further advancement of mineral processing technology. Characterisation, analysis, and simulation of these complex systems provide a fundamental basis for the development of improved mineral processing technology. One of the more recent tools that can be used to help provide a foundation for improved mineral processing technology is high resolution cone beam X-ray micro computed tomography (CT). During the past ten years point-projection X-ray micro CT systems have been used for 3D visualisation and quantitative analysis of multiphase particulate systems. Analysis of packed particle beds containing as many as 30 000 particles can be accomplished in less than three hours with special software to establish the 3D characteristics of each particle in the population and the spatial organisation of the packed particle bed. Now, due to advances in X-ray optics, the resolution afforded with point-projection micro CT systems has been improved by at least an order of magnitude using a lens-based X-ray micro CT system. The development of software tools for the 3D characterisation, analysis, and simulation of packed particle beds using high resolution X-ray micro tomography (HRXMT) is discussed including examples of application in the areas of comminution (particle damage and preferential grain boundary fracture), exposure/liberation analysis (liberation-limited separation efficiency, including coal washability), and filtration/heap leaching (pore network structure of packed particle beds and simulated flow using the LB method of computational fluid dynamics).

Sep 13, 2010

By T QUINLAN

A resource estimate uses data obtained by sampling an orebody. An example is described in which a random drilling pattern did not provide a representative set of assays, and the estimated resource was significantly less than the mine production. It is believed that a better estimate would have been made if the exploration holes had been drilled on a regular grid.

Jan 1, 1992

By M Littlefair, D Gribble, R Rounsley, I Te

Low-density explosives (LDE) have applications where the explosive properties of ANFO are not well matched to the rock. In particular, rocks that are of low strength and/or well fragmented in situ. Dyno Nobel Asia Pacific (DNAP) has developed a new LDE, BlastLiteTM, which can be used as a cost-effective replacement for ANFO with excellent detonation characteristics. The product is based on ANFO with the addition of a bulking agent. The key to the product lies in the ability of the bulking agent to form a homogeneous blend with ANFO without the need for any emulsion matrix to bind the product together. This results in an LDE of low cost and high weight strength compared to existing commercial LDE products. The product has been trialled extensively and has proven to provide results that are equivalent to, and often better than, ANFO with reduced powder factors. This paper details the laboratory development and results of field trials for DNAPÆs LDE solution: BlastLite.

Jan 1, 2004

BHP World Minerals (BHP) commenced development of the Cannington exploration decline in 1993 using Peabody Resources LimitedÆs Mining Services Division (PRL) as the contractor. Approval was given in 1996 to complete the mine development and bring the mine into production in 1997. The total mine development at Cannington by PRL has included 14 km of headings, 1040 m of shaft sinking for ventilation and ore hoisting and 990 m of raise boring for ore passes and vent rises. Hard money schedule of rates contracts were used for mine development from 1993 until early-1997. This took the mine development down to 570 m below the surface and developed six levels. Because of significant risks, the final phase of the mine development was completed in 1997 under a partnering agreement. This paper examines the factors considered in making the change to partnering, the issues involved in negotiating the partnering agreement to complete the Cannington mine development and the outcomes of the agreement.

Jan 1, 1998

By E Kabwe, E Chanda, M Karakus, S Akdag

The Convergence Confinement Method (CCM) is one of the frequently used methods that considers the ground response to the advancing tunnel face. The CCM analytical solutions represent stress relaxation on circular tunnel walls in a rock/soil media. The CCM analytical solutions is based on circular tunnel geometry and consider a hydrostatic stress field in a homogeneous isotropic rock mass condition. However, noncircular tunnel geometries, non-hydrostatic stress field, staged excavation process in a discontinuous anisotropic non-linear rock mass conditions are usually ignored in these analytical solutions. In this paper, we investigate the performance of the existing CCM analytical solutions developed for elastic and elastoplastic ground behaviour for circular tunnels. For this purpose, a finite difference analysis is conducted to compare the analytical results with the results obtained from Finite Difference Method (FDM) for a chosen rock mass condition. Results obtained from the investigation shows that floor, crown and wall displacement are 30%, 10% and 23% more, respectively, in a horse-shoe relative to a circular tunnel. This indicates that the application of analytical formulation tailored for circular tunnels would lead to inaccurate quantification of wall convergence in horseshoe-shaped tunnels. CITATION:Kabwe, E, Karakus, M, Chanda, E and Akdag, S, 2018. Investigating the tunnel closure using convergence confinement method and 2D plane strain finite difference analysis, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 152–159 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

A variety of cement raw materials occur within the Cenozoic sequence in Northland. These form the basis of Golden Bay Cement's cement manufacturing operation at Portland, Whangarei. High grade limestone is taken from the Whangarei Limestone formation, which has been shown to have been sub-aerially weathered and developed mature karst features prior to deposition of the overlying allochthon sediments. In this instance, remobilisation of allochthon sediments following uplift and erosion is inferred. At Portland Quarry, argillaceous limestone is extracted from deformed thrust sheets in the allochthon sequence. Quarry operations have been designed to handle the steep asymmetric folds, thrust faults and fracture zones that affect the resource.

Jan 1, 1999

By N Patzelt, T C. Logan, I B. Klymowsky

In 2003, NEWMONT MINING CORPORATION, the worldÆs largest gold producer, set out to prove that High Pressure Grinding Roll (HPGR) technology is sufficiently robust and reliable to be considered for the treatment of hard rock gold ores. In collaboration with POLYSIUS, a significant trial was conducted and 127 600 tonnes processed, successfully proving the HPGR capabilities on the Lone Tree Mine, Nevada ore û one of the most competent and abrasive ores in the industry. The success has led a number of mining companies to consider HPGRs for the comminution of gold and copper ores.

Jan 1, 2004

At Waiuta near Reefton there is a remarkable vein of quartz <1 m thick which, apart from small offsets on late-stage faults, is a sheet like body essentially continuous down-dip and along-strike for> 1 km. The vein strikes NNE and dips steeply west (032/78¦W). From 1906-1951 the Blackwater mine produced 740,404 ounces of gold from the vein, called the æBirthday ReefÆ, which was one third of the total production from Reefton Goldfield and the fourth largest gold mine in New Zealand. Within the mine the vein is disrupted into a series of northeast-plunging shoots by late-stage faults. Similar faults, but with larger displacements, were thought in the past to truncate the vein at the northern and southern ends of the mine. The implication of this fault dissection model is that offset remnants of the vein await discovery. This study investigated the geometry of the vein and its relationship to host-rock structures and late-stage faults. A new model considers folding and lithological variation in the host-rocks to be fundamental in controlling the scale and geometry of veining, but does not rule out the possibility of some late-stage fault dissection. The Birthday Reef truncates 200-400 m wavelength folds in Greenland Group host-rocks at c.10¦ angle, that results in variation in the structural properties of host-rocks along strike every ~1350-2500 m. The spacing of fold hinges in the wall-rock veins is equivalent to the strike length of historic mining, implying that the Birthday Reef is probably hosted in a single limb of a fold. Similar relationships between mineralisation and host-rock folds appear to be present elsewhere in the Reefton Goldfield (e.g. Capleston and Murray Creek group of mines). Exploration targets are located one fold wavelength (c.1350-2500 m) further along strike from the Blackwater mine and relatively barren rock is expected in between the mine and target areas. Refining the location of folds and different host rock lithologies, using geophysical data and quality geological mapping, is the key to reducing exploration risks and discovering further resources.

Jan 1, 2000

By C A. Myburgh, S Craig, K Deb

In focusing on open pit mine scheduling, one of the biggest areas that a mining engineer can add value is in the area of cut-off grade optimisation. It is not atypical to add up to an extra 20 per cent in value by bringing forward higher-grade ore and deferring costs into the future.There are many techniques available to maximise net present value (NPV) when applied to open pit mine scheduling. That in itself raises the question of why so many of these techniques exist. The short answer is that none of these techniques are robust. Every time the problem changes, the algorithms also have to change.Instead of trying to make a problem fit the constraints of an existing technique, there is much to be said for usefully hybridising different approaches. This paper describes an innovative approach where evolutionary algorithms are combined with both local search and linear programming. The goal is maximising NPV through optimisation of cut-off grade policy and extraction sequence for an open pit mine. The cut-off/cut-over grade policy produced caters for multiple processing streams and stockpiles.Finally we demonstrate the quality of the algorithm by comparing some results with a well-known mathematical solution.CITATION:Myburgh, C A, Deb, K and Craig, S, 2014. Applying modern heuristics to maximising net present value through cut-off grade optimisation, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 155–164 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

The development of Mount Isa Mines Limited power supply is traced through the history of the mine operations. As would be expected, growth of the power supply system follows closely the increase in mine output, although it will be seen that total kWh. produced per ton milled shows a considerable reduction in later years when the mine output showed a more rapid rate of increase. That this reduction is not more marked is possibly due to the increased community and Shire Council power usage per head of population.INTRODUCTIONThe geographical position of Mount lsa, far from any large regional power supply Authority, dictated the policy that the Company be responsible for the production and suppiy of all power required for the plant operation. The Company also, in November 1937, accepted responsibility for the supply of a part of the power requirements of the township of Mount Isa. The history of power supply to the Mine may be divided into several phases.1. The supply Of lighting and power during the first plant construction period 1929-1931.2. The construction of the first section of the Mines Power Station, comprising Nos. 1 and 2 turbo alternators and boilers.3. The addition of No. 3 turbo alternator and boiler.4. The addition of No. 4 turbo alternator and boiler.5. The addition of No. 5 boiler.6. The addition of a. 2 turbo blowers for air supply to the Copper Smelter converters; b. 1 turbo blower for air supply to the L.ead Smelter; c. 2 turbo compressors for compressed air supply to the Mine and surface plant.

Jan 1, 1961

Bacteria can play a key role in the processing of 'difficult' ores. Bioleaching opens the way to potentially extract copper from vast amounts of otherwise hard to process refractory low-grade chalcopyrite. In my talk I will outline our research philosophy to develop bioleaching as a Precision Processing unit process step. In our view, Precision Processing is a sophisticated approach to mineral processing where the ultimate goal is to measure and characterise the ore body in-ground and in real time during mining, allowing the down-stream unit processes (bioleaching, in this case) to be continuously tailored and tuned via feedback and feed-forward controls to obtain the highest possible recoveries at the lowest possible cost and environmental impact. I will describe some of the work that we are undertaking to better understand the interfacial phenomena underlying the fundamental bioleaching process with the aim of coming to a Precision Processing approach. We use techniques such as interfacial electrochemistry (scanning electrochemical microscopy, SECM), AFM, zeta potential measurement, and synchrotron science to elucidate the parameters that drive bacterial selectivity and adhesion, bacterial metabolism, and dissolution and precipitation processes for model systems and real chalcopyrite ores. As examples of our research, I will discuss in some detail our method to produce and characterise micro-patterned CuxS - silica thin films as model substrates for electrochemical and bacterial adhesion work and our approach to the interfacial chemical characterisation of extracellular polymeric substances of bio-active bacterial cells. I will also cover some of our recent findings relating to measurement and interpretation of bacterial adhesion on sulfidic substrates and its implications for bacterial adhesion and substrate selectivity. After having identified and discussed crucial leaching parameters, such as pH, Eh, T, [Cu2+], and [O2], the talk will go on addressing some of the early achievements and challenges encountered in our work to design and prepare low-cost, rugged sensing devices that allow the in-situ (in this case, in-dump or in-heap) localised measurement of these parameters. I will conclude my talk by painting the picture of how the work of our group might contribute to realising the dream of transforming bioleaching into genuine high-tech Precision Processing of minerals. This is an ABSTRACT ONLY. A full-length paper was not prepared for this presentation.

Sep 13, 2010

By Alwan M

At Binebase mineralisation is hosted within an andesitic Neogene volcaniclastic succession on Sangihe Island, Indonesia. Two major alteration types occur; an initial widespread phyllic assemblage of quartz -illite with chlorite, smectite, gypsum and pyrite, and a superimposed quartz - barite - sulphide assemblage. The phyllic alteration arose from a neutral to weakly acidic hydrothermal solution of greater than 200 degrees C, and the quartz - barite - sulphide assemblage arose from a cooler slightly more acidic fluid. This second alteration event is interpreted to have selectively replaced permeable volcaniclastic breccias and coarse lithic tuffs within the altered sequence. Gold and silver mineralisation is associated with the latter alteration, and is locally controlled by the degree of silicification and sulphide abundance. The sulphides present are pyrite, covellite and chalcopyrite. The sulphides are very fine grained with colloform and framboidal textures and were deposited contemporaneously with the bulk silicification of the coarse sediments. A large portion of the mineralised rock has been oxidised to a quartz - barite -limonite - goethite - jarosite assemblage.Coincident gold, silver and antimony geochemical soil anomalies gave the best correlation with anomalous gold and silver grades in bedrock as identified by drilling. Resistivity proved a reliable geophysical method for delineating zones of silicification.

Jan 1, 1990

Neutralization with lime is a simple, cheap, and effective means of treating acid raffinates from uranium processing to' raise the pH, reduce the concentrations of dissolved salts (including heavy metal impurities), and remove amine by adsorption. Two-stage neutralization, using limestone in the first stage at approximately pH 4 and lime in the second, lIlay be advantageous.Lime neutralization of mffinates in the pH range 7 to 8· 5 generally reduced the radium ·concentration to 10 to 200 pCi 1-1, but ·there was considerable scatter in the experimental data. The radium concentration was further reduced to less than 3 pCi 1-1 by co-precipitation of barium (radium) sulphate with 10 mg Ba (as barium chloride) per litre of raffinate. Adsorption of radium on barytes was -also effective in reducing the radium concentration in neutralized raffinate to less than 3 pCi 1-1.The radium concentration of pit water was readily reduced to less than 3 pCi 1-1 when pit water containing 0·01 M sulphate as ammonium, calcium, or sodium sulphate was treated with 20 mg Ba per litre of pit water.Adsorption on barytes was also effective in removing radium from pit water containing 0·03 M sulphate.

Jan 1, 1975

This paper will trace the development of underground coal mining machinery from the days of the tiny air-powered machines to today's 60-ton electric-powered continuous miners. Some important design features which have made the modern fixed-drum continuous miner a success will be examined.

Jan 1, 1978