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By S M. Aminossadati, C M. Stewart, M S. Kizil

Mine ventilation models are now an accepted component of most mine management systems. However, modern ventilation models also represent a highly structured spatial data source, defining underground pathways and connections across a mine. This creates opportunities to extend the use of network models beyond ventilation design, by using critical path algorithms to find pathways such as minimum distance or minimum time.This paper explores the use of ventilation network models to automatically analyse and calculate potential emergency escape routes. A variation of Dijkstra’s algorithm is used to predict complex pathways between any two points across a model, representing an escape route from an emergency area (such as a fire) to a safe location (such as the surface or a refuge station). Weighting can be assigned to paths to represent potential travel speed, obstructions or preferred routes. Finally, emergency considerations such as smoke or gas in some parts of the mine can then be incorporated into the pathways to force the algorithm to avoid dangerous routes and specify safer pathways. Ventsim is used to visually show example results.Emergency egress pathway prediction using ventilation network models can provide an efficient way to quickly predict the quickest or most efficient escape routes for emergencies or planning purposes.CITATION:Stewart, C M, Aminossadati, S M and Kizil, M S, 2017. Emergency egress pathway prediction using ventilation models, in Proceedings Australian Mine Vent Conference 2017, pp 57–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

In order to maintain an accurate survey underground, it is first necessary to connect all shafts used for the transferring of the survey to the levels below by a precise surface survey.This has been achieved at Mount Isa by a careful triangulation survey with stations adjacent to those shafts most suitably located for transferring the survey below.The precedure used is described herein.The Weisbach triangle commonly used is obtained by reading to swingirig wires, the theodolite being placed in line with them as nearly as is possible. The surveyor at the surface places the wires in the shaft as far apart as the size of the shaft will permit, with sufficient space between the wires and walls to ensure their swinging freely. The far wire is fixed in position, while the near one is movable by means of fine adjusting screws to facilitate its being brought into line with the fixed wire and the theodolite. When this is done the surveyor at the lower level is advised by pre-arranged signals and the survey can then commence.The surface portion of the survey is simple; all that is necessary being to read the angle from the backsight to the wires, measure their distance from the theodolite, and keep a check on them throughout the survey to make sure that no movement takes place.The lower portion of the survey is more difficult, the surveyor first qf all having to place his theodolite as nearly as possible in line with the wires.

Jan 1, 1953

By Netchaef P

A rationale is presented for the use of vegetation on mine dumps to minimise runoff and infiltration which become vehicles for potential pollution. The unique topography of mine dumps promotes high atmospheric advection which leads to extraordinary energy levels for evaporation discharge - the driving force of vegetation "pumps". This effectiveness is mainly a function of how well the vegetation will grow on a given site. Recent advances in technology allow water discharge by vegetation to be measured semi-automatically, accurately and cost effectively. As a result the basis now exists for a thorough evaluation of the optimum mine dump vegetation cover. This paper presents the current status of dump rehabilitation as seen by the mining industry. The significant prospects for use of vegetation to minimise mine water related problems with subsequent savings in capital and operational cost are also outlined. However, to examine the crucial questions of optimum hydrological ability, suitability and cost effectiveness of various types of dump vegetation a proposition is made to interested parties in the mining industry: The CSIRO needs potential study sites to evaluate the hydrological ability of vegetation under mine dump conditions.

Jan 1, 1988

A number of mines in Australia have experienced premature detonations caused by bulk explosives reacting with the rock type being blasted. Premature detonations are extremely high risk events as they are unplanned, occurring at any place, at any time, potentially resulting in high loss (personnel and equipment). Many Australian mines have also experienced spontaneous combustion where spilt explosive reacts vigorously with the rock type. Premature detonation in these cases does not occur due to the lack of confinement and the volume of explosive present, but these reactions could impinge on the surface initiation system and provide an early warning of future premature detonations. The explosive ground reactivity phenomena is not restricted to Australia with similar incidents being reported in North and South America, South Africa, China and South East Asia. All reported incidents have two common denominators, being the presence of sulphide rock types and nitrate based explosives. Both premature detonation and spontaneous combustion result from the same series of reactions of partially weathered sulphides that ultimately result in the violent decomposition of the ammonium nitrate based explosive. A number of relatively easily observable indicators can be used to assess a particular minesiteÆs potential for explosive ground reactivity. The presence of two or more of these indicators means that minesite personnel should contact their explosives manufacturer for assistance in determining if a problem exists and if so then developing strategies to overcome the situation. The paper describes the indicators as well as discussing, via a case study, the holistic approach required to efficiently develop a relevant æSafe and Efficient Blasting ProcedureÆ to deal with explosive ground reactivity problems.

Jan 1, 1999

The Beruang Copper-Gold Deposit is located very near the centre of Kalimantan in Indonesia. It is a dacitic tuff hosted deposit currently being explored by Kalimantan Gold Inc of Canada. Exploration activity to date at Beruang has been focused on the Main Zone, which is defined by a north-south elongate, 1 + 1.5 km zone of anomalous copper and gold, and intense phyllic alteration. The disseminated sulfides responsible for the anomalous copper values produce a moderate to high chargeability signature. Phyllic alteration is overlain at high levels, and on the western edge of the Main Zone, by advanced argillic alteration. The dacite tuffs hosting the mineralisation are cut by post-mineralisation dacite dykes that are delineated by ground magnetics and geological mapping. Base metals, principally zinc and lead, form broad halos around the Main Zone. These metals are incorporated in massive NE-trending, polymetallic mineralisation that outcrops to the north and south of the Main Zone. IP survey results highlight the highly pyritic NNE-trending shear zone, which hosts most of the copper mineralisation in the Main Zone. A high chargeability anomaly at depth in the central-east part of the Main Zone is interpreted to be the source for mineralising hydrothermal fluids. This is suggested by zonations in alteration and mineralisation. A deep chargeability anomaly can be correlated with the downward plunge of a pyritic breccia, encountered at shallow levels in drillholes, and is a potential breccia pipe target. Compilation and inversion modelling of the IP results has yielded some interesting drill targets.

Jan 1, 2004

Mining epitomises the challenge of sustainable development, because few sectors have such a direct impact on the natural environment, yet few are more important to the economic and social health of almost every region in the globe. In a global industry, with increasing competition for exploration and mining investment dollars, sustainable development must also be resolved within an international competitiveness framework. In formulating a response to the challenge of sustainable development, the State and Federal Governments do not fully appreciate the extent to which technology drives the solution on a range of issues. In some cases` a dangerous fatalism about the state of science has led to an unhealthy æstop productionÆ attitude that puts our industry and economy at risk. As a technical institute representing the professionals in the minerals sector, The Australasian Institute of Mining and Metallurgy (The AusIMM) sees one of its roles as being to highlight the way in which industry innovation can facilitate solutions. The AusIMM is currently evolving a greenhouse gas emissions policy. As a case study it throws into sharp relief the way in which irresponsible ælimits to growthÆ policies could have a negative impact on the sustainability of the sector, as well as the importance of a technology- based solution. With 80 per cent of greenhouse gas emissions in the next twenty years projected to come from developing economies, such as India and China, major reductions will only be achieved if cost-effective, low emissions energy technologies are deployed in developing countries, and more energy efficient processes of producing key commodities for them are brought online. As a supplier of the key energy resources and materials that will be in high demand to feed developing economies, and with knowledge intensive industries with excellent R&D links across mining and manufacturing, Australia is well positioned to contribute to develop key low emissions technologies. However, we will only be able to take advantage of this position if the Federal Government commits to a holistic greenhouse emissions policy that does not penalise industry. We need effective æpushÆ polices aimed at leveraging investment in low emissions R&D that are closely linked in to æpullÆ policies aimed at stimulating technology uptake.

Jan 1, 2006

May I first of all say that I am fully conscious of the great compliment paid to me when I was invited to accept the Presidential Chair for this current year. I realise that it is an onerous task by reason of the fact that the Chair has been occupied in the past by so many able and distinguished men, and I realise also that I have been set a standard which is hard to emulate. "It is my desire however, in accepting the post that I may be able to contribute in some small measure to the further advancement Of the aims and objectives of the Institute and I thank you all for the confidence you have shown in me.Secondly, on behalf of the Company and in my Presidential capacity, I want to extend to each and everyone of you a hearty welcome to Whyalla and I hope that you will all return to your respective fields of endeavour feeling that you have had a most interesting, enjoyabIe and instructive time with us here in Whyalla.In this year of 1951 marking as it does the culmination of the first 50 years of Federation in Australia and yet another half century of human endeavour and progress, we are brought to a point where it is perhaps natural that we should pause, to review what has been achieved, in that span of time, and to look at the tasks ahead.It is no exaggeration to say that the story of Australian development since the inauguration of the Commonwealth 50 years ago has no more remarkable chapter than that of the-growth of its manufacturing industries.Each decade has borne witness to steady and substantial growth of our secondary industries and whilst it is true that our financial well-being still rests heavily on our primary production, we have, as a nation, moved surely in the direction of a more balanced economy. More and...

Jan 1, 1951

By P Andersson, P Marklund

Evaluation of different techniques for bottom fill stabilisation showed that frozen fill was the most economical method. In order to test the method a full-scale field test was performed in the Rehnstr÷m mine. The test was instrumented with temperature gauges and extensometers. Before the field test, frozen fill was tested at the laboratory. The mechanical properties of the frozen fill were determined by uniaxial compression and creep tests. A deformation model for the frozen fill was set up. Calculation procedure for design of spacing between the freezing tubes, time for freezing and calculation of the necessary capacity of the refrigeration plant was developed. These procedures were calibrated against the field test. The results of these investigations allow the following conclusions: From a mechanical point of view, frozen fill has excellent properties as a structural member and it also has excellent properties to support itself and the fill above. Methods for the thermal and mechanical design of freeze stabilisation have been developed and found adequate. The need to place the freezing tubes several years in advance of the future sill pillar mining, requires careful long-term planning and accurate documentation.

Jan 1, 1998

By N C. White, L Danyushevsky, D R. Cooke

Comb-layered textures preserve the cyclic accumulation and release of volatiles inside magmas that are temporally associated with large Cu-Au-Mo-rich porphyry ore deposits. Fluid inclusions in these textures sample pristine magmatic fluid. Microanalysis of this fluid helps constrain the physical models that operate at melt-fluid interface and in the broader magma system responsible for ore deposit formation. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Belcher C. B

A simple gravimetric procedure was developed for the rapid determination of carbon dioxide in coal mine roadway dust samples and the result is used for the subsequent calculation of incombustible matter contentaccording to the requirements of the Queensland Coal Mining Act. The carbon dioxide is determined through loss of mass by a semi-enclosed apparatus, following room-temper.ature hydrochloric acid attack on the sample.With a sample containing 36 per cent carbon dioxide, the achieved standard deviation (ls) of 0·3 per cent CO. is adequate for coal mine roadway dust analysis.This simple procedure enables relatively unskilled labour in mine laboratories, to analyze coal mine roadway dust samples in accordance with the Act. Some 50 analyses can be achieved per day compared with 8 by the Australian Standard Method for coal.

Jan 1, 1976

The development of metallurgical training is briefly reviewed. The reasons for the current trend for Metallurgy Schools to become Schools of Materials Engineering or Materials Science are mentioned as is the role of Departments of Chemical Engineering in the teaching of extraction metallurgy. Some problems on academic staff recruit- ment are highlighted and predictions concerning future difficulties in industry getting adequately trained professional staff are made. The need for a special effort to attract and retain the best undergraduate students is put Forward.

Jan 1, 1987

By Meloy TP

Several important, fundamental aspects of the grinding behaviour of mineral systems are addressed. The Levenberg-Marquardt algorithm for systems of constrained non-linear equations was used to solve the steady-state and dynamic population balance model (PBM) grinding equations to obtain the mill matrices and grinding selection and breakage rate functions, respectively. The fact that the PBM model equation Inverse Problem is degenerate or underspecified is demonstrated. Multiple solutions to the same PBM equations are provided. It is shown that there is no unique solution to the Inverse Problem unless additional constraints are provided or assumptions are made such as the Arbiter-Bhrany normalisation assumption. The severity of the non-uniqueness problem for steady state grinding is demonstrated in several examples using typical feed distributions and mill matrices. In addition, it is also demonstrated that when higher than single powers are used in steady-state mill matrix expressions during simulation or calculation (or iterative procedures are used during numerical simulation) and four or more size intervals are used considerable amount of error is propagated throughout any calculation. Each solution to a PBM, while giving the same prediction during a single mill pass, gives different solutions or predictions for mill composition upon subsequent passes. In addition, it is shown that there is a problem with building up a grinding mill knowledge base with PBMs. A similar analysis was done for the dynamic or kinetic PBM equations. The fact that the dynamic PBM Problem is degenerate or underspecified is also demonstrated. Multiple solutions to the same dynamic PBM equations are provided. Again, it is shown that there is no unique solution to the Inverse Problem unless additional constraints are provided or assumptions are made such as the normalisation assumption. Each solution to a dynamic PBM, while giving the same prediction for a given grinding time interval, gives different solutions or predictions for mill composition for other grinding times. Actual experimental grinding data was assessed to determine the functionality of mill selection and breakage functions. The functionalities obtained through constraints were compared with those obtained with the normalisation assumption of Arbiter-Bhrany which relates breakage functions to particle size distribution. The capability of the population balance model to predict grinding behavior over time in various mineral grinding systems was assessed. The required functionality of selection and breakage functions for effective prediction of grinding behavior in mineral systems is discussed.

Jan 1, 1993

Over the past several years, copper prices have surged from under a dollar to over three dollars a pound. However, the long-run trend in real copper prices since at least the early 1970s has been sharply downward. While many now contend that the long-run trend in real copper prices is now upward, the result of structural changes in this market, others are sceptical. Nor is copper unique; the prices for a number of other metals, including aluminium, iron ore, lead, nickel and zinc, have followed similar patterns. This paper examines the forces behind short-run and long-run trends in metal prices. It first focuses on the short run, where it argues that shifts in demand are largely behind changes in prices. It then turns to the long run, where it concludes that production costs and supply largely govern price trends. Finally, it explores several implications of these findings, including those for diversification and market risk, for forecasting mineral prices, for assessing the growth of metal demand in China and elsewhere on metal prices, and for changes in the long-run price trends.

Jan 1, 2006

Groundwater issues for the mining industry are many and varied. When the depth of mining is below the water table/potentiometric surface, a groundwater æsinkÆ is created which alters the local groundwater flow regime resulting in minewater inflows. Assessment of mine dewatering, mine water balance and wastewater disposal requirements are central to the effective management of water in a mining operation. Each of these issues has a significant groundwater component. Other groundwater issues for mining operations include: water supply, aquifer storage and recovery, the impact on other groundwater users in respect of groundwater levels, bore yields and water quality, and the development of an effective groundwater monitoring network for early detection of impacts and to satisfy regulatory requirements. This paper outlines the techniques involved in assessing groundwater issues for project feasibility, during operation and post closure, and provides an overview of several mine dewatering and water disposal methods. The practical assessment of groundwater issues for the mining industry is illustrated with several case studies of mining projects in Australia, SE Asia and the subcontinent. These are projects to which the author has contributed during a career as a geologist/hydrogeologist spanning more than 25 years.

Jan 1, 2003

By Gurgenci H, Slifirski M

The Centre for Mining Technology and Equipment was established in 1991 to develop innovative technologies for the mining and processing industries, to introduce these technologies to the industry, and where appropriate, to co-operate with equipment manufacturers to transform these technologies into equipment products. It is an unincorporated joint venture between the University of Queensland, CSIRO and the Australian Minerals Industries Research Association. Base funding for the CMTE is provided by the Federal Government as a Co-operative Research Centre.

Jan 1, 1993

By G P. J Dijkema, M A. Reuter

From a material cycles perspective all processes are interconnected and consequently a process can never be evaluated as an isolated and independent unit. This also holds true for the evaluated co-incineration options. Environmental and sustainability issues for example, such as raw material and energy utilisation or air pollution, are a resultant of the whole system of industrial activities. It is therefore important, not to optimise a single process or industrial activity, but rather the whole system. Although engineering procedures for the design of individual industrial units are well developed, the problem of determining the best arrangement of these interconnected units is often far more difficult. Regulation that manages the arrangement of the units for waste processing is still under construction. In the evaluation of co-incineration, analogous principle from process control can be used: feedforward control. This principle includes the determination of which outlets can be used for all process outputs, hence avoidance of any æunusableÆ products or wastes possibly arising from co-incineration. To establish the extent, to which produced wastes are usable, a system overview is necessary, in addition to in-depth information on the subsystems, which produce and can consume wastes. Material cycles modelling can be used as the basis for a tool that supports the development of a suitable playing field. It should provide overview of the system and in-depth information on its subsystems. This tool then represents an attempt to bridge the gap between æholisticÆ industrial ecology and process engineering.

Jan 1, 2000

By C J. Corbett

Many underground mining methods rely on blasted rock moving under gravity to report to extraction points. Mining of orebodies dipping between 20 - 45 degrees poses a unique challenge for mining engineers in that a dip angle in this range will not allow the movement of broken ore down the footwall to the mucking horizon utilising gravity. This is more so in cases where the natural angle of repose of the rock is less than the dip of the orebody. Hence, innovative mining systems are necessary to mine this type of orebodies. In Australia, the method of uphole retreat panel stoping is commonly used to extract orebodies in the dip range of 20 - 45 degrees and thickness range of 5 - 15 m. In the Zambian Copperbelt a method called continuous retreat updip stoping is used for orebodies with similar dips and thicknesses. The mechanised form of this mining method has potential for application in the metalliferous mining industry in Australia. In this study a comparison is made between mechanised updip (MUDS) and transverse retreat stoping (TRS) methods. A hypothetical nickel sulphide orebody located in Western Australia is used as case study. The net present value for mechanised updip stoping is seven per cent higher than that of transverse retreat stoping based on the assumptions applied. Initial results of this study indicate that mechanised updip stoping can be adopted for Australian mining conditions. However, lack of significant local experience with the method is often cited as a reason for not adopting it even in situations where it is clearly the best option.

Jan 1, 2003

Just as Australia is part of the Pacific Rim, so the Pacific Rim should be viewed as part of the whole world. That applies in particular to that scarce commodity û money. There are five main factors of production in any mining development û mineralisation, materials, manpower, management and money. LetÆs focus on the upstream input û mineralisation, and the downstream input û money, especially in the area of communications. Unknown to many, the Competent Person reporting on Mineral Resources and Mineral Reserves has a direct and unavoidable impact on the companyÆs financial statements û the profit and loss account and balance sheet. With respect to reporting of the major asset of most mining companies û the resources/reserves û investors are getting a better deal now than at any time in memory as regards flow and adequacy of information. Australia has been a world leader in this regard. The outlook is for even more informative and useful reporting. The more rigorous reporting requirements for Exploration Results and Mineral Resources/Reserves, which have become a worldwide phenomenon over the last five years, will continue. This will be positive for the mining industry as a whole and for Australia in particular. However competition for the scarce investment dollar will also increase. Put simply, mining has many competitors, unconnected with mining, for the capture of the investment dollar. It behoves all participants to recognise that there are three investment factors which influence strongly the willingness of investors to put money into mining. These are Confidence, Credibility and Consistency. AustraliaÆs investment image stands high in these three respects, but the competition will continue to grow. AustraliaÆs lead must be maintained. However, some investment decisions should not necessarily be based on fundamental, quantifiable facors. Some of these are outlined.

Jan 1, 2004

At many locations in Australia the decommissioning of mining operations will require the disposal of excess water. If the water is contaminated its disposal may be restricted by government guidelines. The timing of water disposal may be critical to the schedule of close-out. The uncertainty of the annual rainfall input to the water storage and disposal system may determine the success or failure of close-out. The uncertainty associated with any outcome can be used to determine the reliability of the system, or inversely its risk. The technique of Monte Carlo simulation, using the uncertainty in annual rainfall, is applied to quantify the risks associated with water disposal as part of the requirements for close-out in two case studies. In both case studies it is assumed that water disposal is via evaporation only. The first case study is the Nabarlek operation, located about 270 km east of Darwin. This project is required to complete the engineering work associated with its close-out by December 1995. The second study investigates the situation of close-out for the Ranger Uranium Mine, about 250 km east of Darwin. It should be noted that the Ranger mine was examined as part of the annual update of its contingency rehabilitation plan and the probability of implementing the plan is extremely small. The probability of success for the Nabarlek case varied from less than ten per cent to greater than 95 per cent depending on the management strategy. Four possible strategies were investigated for the Ranger mine with the chance of success varying between 20 and 95 per cent. The estimation of the evaporation rate and the area allocated to evaporation was critical in both cases. By applying seasonally based evaporation pan coefficients determined on site, rather than an average monthly value of 0.75, the chance of success was improved by up to 35 per cent for Ranger. Simulation modelling is able to provide information on the likely response of mine water management systems and the level of risk. This information is required to efficiently plan and manage the disposal of water for close-out.

Jan 1, 1994

By Scholl EW, Ricken W

The simultaneous presence of fuel, oxygen, and of an ignition source is necessary for an explosion to arise. If one of these conditions is missing an explosion cannot take place. A continuous reduction of oxygen, often applied as a protective measure in surface plants, is not to be considered for underground mining because of possible danger to persons. Therefore, measures for avoiding explosions can only be concerned with lowering methane and coal-dust concentrations to an undangerous level and avoiding ignition sources. As these measures alone are not sufficient, additional ones have to be taken to keep the effect of an explosion as low as possible. Measures for controlling and monitoring methane are essential. Although the formation of dangerous coal dust concentration cannot be avoided it can be reduced. Dust-binding by means of hygroscopic pastes and dusting with limestone dust are effective measures to pre vent explosions.

Jan 1, 1981