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By Polthier K

A short discussion of the salient aspects of a dispersed flow model in relation to the gas flow in blast furnaces is given. The use of the theory in assessing vessel performance is mentioned. Tracer results of a blast furnace (688 m3) from three furnace levels and different radial positions are analysed and results presented as D/ud values. The significance of the shapes of experimental tracer curves are included and comparison is made with results obtained on other furnaces.

Jan 1, 1975

By Swanson AR, Nicol SK

A study has been made into the influence of feed size distribution on the flotation response of coal. The results show that a full description of the flotation response of a coal must not only consider the inherent floatability of the coal, but also, the size distribution of the feed to flotation. The performances of a number of flotation circuits were compared using a coal which was "poorly floating" because of its size distribution. Split feed flotation, two stage reagent addition, and reflotation of classified tailings all gave better yields than that obtained by conventional single stage flotation. The optimum flotation circuit for the washing of the coal in question, was reflotation of classified tailings.

Jan 1, 1978

By R Milton, D Hake, H Sprague

The North Western Sewer tunnel extends over 11.5 km in the North Western suburbs of Melbourne.The $253 million tunnel project provides a critical link in the Melbourne Sewer Network. The existing sewers fail to service the increasing demands of the growing population of the North West regions of Melbourne. This project will protect the environment and improve the standards of service of the existing system. This paper concentrates on Section three of this project, consisting of the final 4 km of the Contract, three access shafts and a cut and cover section of tunnel.Transfield Tunnelling as Head Contractor constructed the tunnel for Melbourne Water Corporation, with Enetech Streamline, formally Streamline Australia, a trading arm of Melbourne Water acting as Superintendent.Excavation of Section three of this project commenced in September 1994 and project completion is scheduled for October 1998. The tunnel passes below the residential suburb of Essendon, through some of the most challenging ground conditions ever attempted to be tunnelled in Australia.

Jan 1, 1999

By M Chappell

This paper describes the design of the steel fibre reinforced precast concrete (SFRC) segmental lining for the intake and discharge tunnels for the Gold Coast desalination plant in Queensland. In addition, the key design requirements and design methods for the lining of these 2 km long, 2.8 m internal diameter tunnels, including structural, durability and maintenance requirements are discussed. Details of the segment configuration and erection process are presented along with information on the manufacture and trial testing of the concrete for the segments. The paper also gives a brief introduction to steel fibre reinforced concrete behaviour. Construction of the tunnels commenced in April 2007, and the authors believe this is the first application of this technology in Australia.

Jan 1, 2008

Platinum Group metals have been known in New Zealand since the 1880's but not produced on a large scale. They have been neglected because their value was not appreciated rela- tive to gold and their value was often very low, reflecting demand, and because recovery was difficult compared with recovery of gold. With the rising price of most Platinum Group metals and the perfection of gravity and flota- tion recovery methods, recovery of platinum along with gold from alluvial deposits is more attractive. Platinum Group metals are known in several different environments in New Zealand, ranging from alluvial placer deposits to layered basic to ultrabasic intrusions and quartz veins. None of the known occurrences have been ade- quately prospected and there is a real possibi- lity of future discovery of important deposits. Several New Zealand based and at least two offshore resource companies are currently involved in exploration, prospecting or mining for Platinum Group metals in New Zealand.

Jan 1, 1987

By McMahon DW

The major components of a mineral reserve estimate for project development purposes are described with respect to sampling, geology, estimation methods, mining factors, metallurgical factors, environmental factors, financial and other factors. Each of these components impact to varying degrees on the recoverable metal or product of a new mining project. The evaluation of a project is a complex process involving the best the profession can provide in terms of geological understanding, engineering ingenuity, metallurgical skills and financial evaluation.

Jan 1, 1983

By Hayes P. C

The kinetics of reduction of PbO-silicate melts in CO-N gas mixtures at 900¦C have been studied. Rea~tion rates were measured by moni- toring the CO2 content of the product gas. A wide range of gas and melt compositions and gas flowrates have been investigated. The overall reaction rates in heterogen- eous systems are typically characterised by a steady increase as the gas flowrate is in- creased. At low flowrates the processes are limited by gas film mass transfer. At high flowrates it is expected that the rates will tend to maximum values determined by either the rate limiting chemical reaction or diffusion in the condensed phase. In the present series of experiments it has been found that for any given gas composition the overall reduction rate goes through a maximum with increasing gas flow. The maxima, which occur at relatively low gas flows, are more than an order of magni- tude greater than those observed at high gas flowrates. The results of these and other experiments are presented and analysed. Possible rate limiting mechanisms in the reaction system and their implications regarding commercial reactors are discussed.

Jan 1, 1987

By Just GD, Phillips R

The application of high pressure water jet technology to the drilling of longholes in coal has resulted in the development of a system currently capable of drilling to lengths greater than 200m. Field tests at the German Creek Mine have demonstrated directional control of the holes within a 0.5m section of the seam. Initial application of the technique at the German Creek operations is for drilling methane drainage holes. These developments, in three stages, result from support by the National Energy Research Development and Demonstration Council

Jan 1, 1991

Mine planning is difficult. Even for small operations, it involves reasoning with complex variables and the practical difficulties of mining. It is also about predicting and planning the future in an unpredictable physical and economic environment. Yet we rely on a handful of individuals and their spreadsheets to tell us how to do it û planning the business and activities of mining to hopefully produce results that will please stakeholders. Does it work? Not as well as it could. Planning affects everyone in the organisation. Company executives are demanding more reliability and stability in cost and revenue forecasts from their operations. Management want to explore ways of being more cost effective. Miners and contractors want more useful plans and realistic targets. And the planners have to describe the method that will translate business objectives into implementable plans. Even with the use of computer technology a lot of effort is expended to produce plans that are largely qualified by the level of knowledge and experience of individuals. Better use of information and the application of Intelligent Technologies can improve the quality and reliability of mine plans and schedules. By capturing the knowledge within the organisation and speeding up the planning process, Intelligent Technologies allow more options to be considered more rigorously. But it is not just about technology. It is about how technology is implemented and embodied in the way the business is managed for performance. When this happens, the real benefits of better planning start to flow.

Jan 1, 2003

By Fulton E, Ring RJ, Waters DJ

Laboratory leach tests of Nabarlek uranium ore carried out by the Australian Atomic Energy Commission to compare the effectiveness of Caro's Acid1 (permonosulphuric acid) as an alternative oxident to pyrolusite indicated reduced acid consumption in leaching and lime savings in neutralisation of tailings liquors when using Caro's Acid. Interox Chemicals Pty. Ltd. arranged a plant trial for Caro's Acid at Queensland Mines Nabarlek Plant. The trial confirmed that significant savings in acid and lime can be achieved under plant conditions. Plant operations also demonstrated improved redox potential control was possible using Caro's Acid.

Jan 1, 1978

By A S. Bamber

Mining is the oldest industrial practice on the planet with a history dating back over 3000 years. Since the early iron age ores have been extracted for use in a variety of contexts by humankind, from domestic to military, transport and more recently for complex industrial applications. Mineral exploration and extraction has evolved from the early exploitation of primary metal occurrences in relatively small quantities such as iron, gold, coal and copper, to the bulk mining and extraction of highly complex polymetallic oxides and sulfides today. Since the industrial revolution, mining practice has evolved substantially to support an increasing range and quantity of required metals and to accommodate the increasing scarcity of high-quality sources of these metals. A common response to the increasing scarcity of mineral resources has been to expand production through simple economies of scale, thus diluting fixed costs. This approach, however, is increasingly ineffective in the face of current trends, that include increasingly complex mineralogy, increasing pressure on environmental footprint - energy in particular, and increasing scarcity of capital for the construction of presently popular æmega-minesÆ. This paper examines historical trends and current practice in mineral exploitation in the light of the current global revolution in social, environmental and economic values as the projects move towards a vastly different topology for the industry for continued success in years to come.CITATION:Bamber, A S, 2012. The mining industry needs to be shaken and stirred, in Proceedings Narrow Vein Mining 2012 , pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

By Steinbrucker G

Improvements in mining by the application of electronics necessitates analy-sis of the objectives and problems. A detailed analysis has shown that increased tunel-ling performance is one of the most important objectives. In mining, the environmental conditions for machines, their handling and servicing are very hard. Therefore a health monitoring system for tunnelling machines in hazardous areas has been developed. This system measures operational parameters, such as-flow, pressure, temperature, etc., de-rives forecasts of possible failures from these values, and assists maintenance person-nel. Important data are transmitted to a surface computer via telephone cables. Health monitoring is based on the cognition that slow deterioration of characteristic parame-ters, e.g. fluid loss, are symptoms of wear. Sudden changes of machine parameters indi-cate sudden destruction. Computer technology is very advanced, but transducer technolo-gy has not,been able to keep pace. Filling the yawning gap in the mining industry is a challenge to technology and requires special techniques. Machine monitoring and automa-tion in underground mining is still in its infancy. A lqt of development and research work is still necessary. The risks are great-The expected benefit due to increased min-ing performance (up to 5 %) justifies the risks in development.

Jan 1, 1985

The geologic settings, geochemistry of host rocks, mineralogy and metal values in modern back-arc volcanic-hosted massive sulphide (VHMS) mineralisation are very similar to those in many ancient polymetallic VHMS deposits. The geology, distribution and styles of seafloor mineralisation in modem back-arc basins, especially the eastern Manus and Lau Basins, southwest Pacific, are compared to VHMS deposits in the Mount Read and Mount Windsor districts of Australia . Based on exploration and research in modem back-arc settings, geologists are now observing the direct analogues of the polymetallic VHMS deposits currently being exploited in ancient back-arc volcanic belts throughout Australia and the world.

Jan 1, 1995

By Henderson J

Iron ore samples selected from the Deepdale, Iron Prince and Mt. Newman ore bodies have been pelletised on a pilot scale plant and subsequently reduced under laboratory conditions by hydrogen or carbon monoxide. Pellets approximately 1 cm in diameter have been reduced by hydrogen over the temperature range 5000- 900¦C and the results examined by thermogravimetric, microscopic, electron probe and x-ray techniques. After an initial time delay it was found that up to 95% reduction the rate of reduction could be described by a transport con- trolled porous model, in which the effective diffusivities of hydrogen in theòpr¦duct layer and the reaction zone are filar. Independent measurements of effective diffusivity supported the values obtained from the reduction data. ve 95% reduction the rate decreased markedly due to the formation_of retained wustite or fayalite. Comparison with reduction by carbon monoxide over the temperature range 7500 - 900¦C showed that the rate eduction by carbon monoxide was approximately five times slower than the rate by hydrogen. The rate of reduction was found to be a function of the properties of the pellets, which may account for the ely conflicting results that have been obtained in previous investigation on porous pellets.

Jan 1, 1970

THERE is available a considerable amount of literature concerning the practice, and, to a smaller extent, the theory of ventilation as it applies to coal mines. Publications considering the subject of ventilation of metal mines from a practical viewpoint are much less numerous, whilst the treatment of the theoretical aspect of the question (except in so far as is common to coal mining) appears to have been almost neglected. This may be due to one of two causes (a) That in many metal mines (especially those which have not attained a great depth), on account of the greater number of connections with the surface, as compared with coal mines, natural ventilation has sufficed.(b) That in metal mines where the foregoing is not the case the solution of the ventilation problem from theoretical considerations has been regarded as involving so many complications that any attempt at the determination of a set of concrete ventilation figures applying to and throughout the mine would be futile. Whilst it is freely admitted that the difficulties inherent in the application of theory to the ventilation of metal mines are numerous, it must also be admitted that few attempts have been made to overcome them. The ultimate aim, of course, would be the collection of sufficient data to enable the probable behaviour of the air-currents throughout the whole of the workings of any mine to be accurately predicted under any particular set of circumstances. Failing the attainment of this goal of perfection, it would at least appear that much valuable information might be obtained. In ventilation, as in...

Jan 1, 1921

By Phillips RN

Semi-confined, trachy-andesite sills which overlie the German Creek Seam, within the critical tensile strain zone, form major groundwater hazards to longwall mining at the German Creek underground mines. The water contained in these aquifers is normally neutral, but highly saline. Techniques used to detect aquifers include routine air-lift pumping in exploratory drill holes, downhole geophysical and geological logging and upstage packer testing. Hydraulic constants are calculated from pump-out and pump-in test results. Hydraulic parameters for the calculation of mine inflow rates are determined from pump-out test results because these tests appear to be more representative of aquifer drainage during goat dewatering than pump- in testing. During mining of the first longwall block at Central Colliery, caving fractures intersected overlying aquifers after the longwall had retreated 40m, and mine water inflow rate rapidly increased from less than one litre/sec to 25 litres/sec. The amount of water pumped out of the mine during first panel extraction was 140 megalitres with drawdown occurring over an area of 168 hectares. In the Southern Colliery area approximately 324 megalitres of highly saline water which is actively stored in the Aquila Sill area will be pre-drained from six well points prior to longwall mining. With effective pre-drainage from surface drill holes, maximum inflow rate into the mine during initial goafing can be reduced from 165 litres/sec to about 45 litres/sec.

Jan 1, 1988

By Fee BS

This paper describes four new families of collector products which are currently being introduced at the industrial level. A brief summary of the chemical basis behind each product family will be given. This is then followed by a selection of flotation examples which illustrate the more important use characteristics that have been observed to date. It is becoming more apparent with further testing that these four new product families can offer both technical and economic advantages to the industrial flotation process operator.

Jan 1, 1993

During 1995 a catastrophic accident took place at the No 2 Vaal Reefs shaft in South Africa, when a locomotive fell onto a cage, causing the death of 104 people. The subsequent Commission of Enquiry found that the safety detaching hook had opened when hit by parts of the falling locomotive, detaching the cage from the rope and allowing the cage to drop 400 m down the shaft. It was believed that had the hook not detached, the rope would have been sufficiently elastic not to have failed, implying that many fatalities may have been avoided. In addition, the risk of accidental opening of hooks due to impact with smaller falling objects in shafts became a concern. This paper deals with a comprehensive statistical investigation that was performed to quantify this risk, establish acceptable levels of such risks and to derive criteria for the resistance of detachment hooks against accidental opening caused by impacts. The investigation involved a survey, dynamic finite element analyses and Monte Carlo simulations.

Jan 1, 2005

A good blasting result is largely achieved by putting the right amount of explosive in the right place and firing it in the right sequence. The best blast design in the world will not break the rock if the planned blast layout is not achieved in the field. One of the critical inputs into a blast design is the diameter of the blasthole. An assumption that the actual blasthole diameter is equal to the nominal drill bit size is generally made. However, a small deviation in the actual hole diameter from that assumed will have a dramatic effect on the hole's volume and, consequently, where the explosive is placed in the blasthole. Any discrepancy in actual blasthole volume from that assumed will be reflected in 'overloading' or 'underloading' of the blasthole with the calculated explosive quantity and, thus, reflect in explosive distribution and stemming lengths. When loading to a 'collar' in an oversized hole extra explosive will be used, resulting in higher than planned powder factors and explosive costs. A blasthole diameter assumed from a nominal drill bit size is an incorrect assumption. This paper will present some actual blasthole diameter measurements illustrating the variation in hole diameters seen in the field and proposes a practical method for achieving a useful blasthole diameter measurement.

Jan 1, 1990

An integrated computer system (the Short Term Mine Management System) has recently been developed by B.H.P. Steel Long Products Division in Whyalla, South Australia for use in their open pit iron ore mines.The system incorporates blast design, comprehensive blasthole data handling, grade coilrol, stockpile scheduling and management and reconciliation within a single, user friendly computer package. The blast design system allows the blasting engineer to design the layout of holes for a production blast using geological information projected from the bench above to aid in appropriate blasthole positioniog in particular rock types. The grade control system allows mining blocks to be designed and evaluated from blasthole information using interactive graphics processes. The handling, storage and reporting of blasthole survey, assay and geological logging data forms an integral part of this system. Stockpiles can be constructed from a number of mining blocks to reach a specified target grade using the stockpile management system. Although not yet integrated, the reconciliation system will reconcile stockpiles back to mining blocks and to the geological model.

Jan 1, 1990