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In the- past, at Great Boulder Gold Mines Ltd,, ,' s.. number of attempts ' ha'tre been made to remove water ' `solublo copper and' iron sa'lt's from calcined pyritic concentrates, but various problems have arisen and the methodsi ve been abandoned. A method of rapid washing has now been developed,, and although some problems still. exist,, a workable `process has boreh established .which. has; resulted in 'substantial savings of 'reagents used for. the. cyanidation of calcine

Jan 1, 1964

The Oregon-Idaho graben evolved after widespread Uwleiitic flood basalt volcanism associated with the arrival of the plume head of the Yellowstone hotspot beneath southeastern Oregon approximately 17-16 Ma. The north- to north- northeast-trending, 50 km-wide graben evolved between 15.5 and 10.5 Ma during east-west extension. The graben is part of a middle Miocene back-arc rift (1,100 km long) that includes the northern Nevada rift, the Baker and LaGrande grabens, and the Chief Joseph dike swarm of the Columbia River Basalt Group. The graben ceased to be a volcano- tectonic depression as the cross-cutting western Snake River plain began to evolve at approximately 10.5 Ma.

Jan 1, 1995

A mining operation can be identified as demonstrating prudent management when a number of vital characteristics are evident.All risks and opportunities that are critical to the on-going success of the operation have been identified and are being effectively managed. All significant tasks and events are plan driven. All levels of management visibly support the policies of the operation through their attitude, behaviour and actions as well as words. Supporting evidence for required activity and the outcomes is readily available. Improvement mechanisms are working to advance the key business processes. Everyone is working towards satisfying the needs of the stakeholders of the operation. When these characteristics are integrated with the satisfaction of all legislative requirements, all industry codes and optionally all relevant international management system standards then an operation is fulfilling all the requirements of a Due Diligence Process. The majority of mining operations do not show all of these characteristics and therefore unnecessarily suffer from missed profit opportunity and constant cost pressure, less than acceptable safety and health and environmental performance and consequent poor relations with employees, unions and regulators. In these operations the characteristics to be observed are quite different.Serious incidents are occurring with no sign of a rate decrease. The operation lurches from one panic ituation to another. Management are absent in their leadership, but very active in developing rules and enforcement methodologies. The operation has no history. Re-inventing the wheel with employees who come and go at an alarming rate seems to be forever occurring. All efforts are directed at controlling the business outputs with a strong emphasis on blame. Everyone is trying to look busy to avoid the ever-present cost reduction threats. To change to more prudent management utilising a Due Diligence Process is not theoretically difficult. However it does take clear direction, focussed efforts, supporting actions with appropriate tools and perhaps most importantly an internal desire and drive to become such an operation. A Due Diligence Process is about doing the important things that have to be done, providing the understanding of why they are important, demonstrating proof of activity and effectiveness, and leading the way through effective management.

Jan 1, 1998

By Cairncross A. A

Papers on technical aspects of the Melbourne Underground Rail Loop project are being presented at this conference or have been presented previously or will be presented at other forums. This paper provides the framework for these papers by presenting the overall engineering tasks. The conceptual design, the special investigations undertaken, the management of the project and the construction development are highlighted.

Jan 1, 1981

By G Gibson

Realising that current roadway development performance levels were unlikely to sustain new generation high-capacity (15 Mt/a) longwall mines then being planned, the Australian Coal Association Research Program (ACARP) established a Roadway Development Task Group (RDTG) in 2005 to develop a research strategy targeted at improving roadway development performance in Australian longwall mines. The initial phase of the project identified a number of factors that differentiated best practice mines from others, and proposed a multi-faceted research strategy encompassing both short- and long-term research initiatives, including:conducting regular benchmarking studies across the industry to identify factors contributing to improved performance and to monitor performance trends,conducting regular industry roadway development operatorsÆ workshops to facilitate the transfer of successful roadway development improvement initiatives throughout the industry and facilitate networking between development practitioners,development of alternative skin reinforcement and containment measures that would eliminate the use of steel mesh and enable face support systems to be fully automated,development of automated bolting and mesh handling systems that would enable operators to be removed from the immediate face area,development of a body of knowledge of industry roadway development practice,development of a web-based information management system to capture and transfer emerging developments in roadway development practice and technology,reviewing the Australian civil tunnelling and underground metalliferous mining sectors to identify practices and technologies that could potentially be utilised to improve roadway development performance, anddeveloping a new generation high-capacity mining system capable of +10 metres per operating hour for 20 or more hours per day (CM2010). The paper reports on the progress of the above initiatives and outlines strategies to continue the pursuit for improved roadway development performance.

Jan 1, 2008

By P Chapman, B Moosapoor

The objective of this paper is to present the potential applications of geostatistical analyses in planning CPTu investigations, as well as interpolation of CPTu data. The paper presents a case study of a geostatistical analysis of CPTu data undertaken between 2004 and 2017 for an upstreamraised TSF located in the Goldfields region of Western Australia. An initial model is developed using the 2004, 2009 and 2017 CPTu data. The model is used to predict in situ cone tip resistance (qc) measurements, as the interested primary variable, at the selected locations where 2019 CPTu were undertaken, and the results of the prediction and the actual data are compared.

Jul 1, 2021

Computers and other microprocessor technology lead the world of technological change. Nevertheless, the real advances in the world at large are not necessarily in the computer industry, but in the industries whose economics benefit most by the advances that this computer revolution makes possible. The minerals industry has always been in the forefront of this advance. Technological change in the era preceding the industrial revolution, and the mining industry's part in it, provides an instructive lesson for what is happening today. Strong parallels can be drawn for predicting future advances. With each technological advance allowing more efficient production comes a re-alignment of economics - absolute and relative changes to prices, to quantities demanded, and to other market characteristics. This re-alignment applies not only to the mineral industry, but also to the world at large. Adaptability, rather than technical advancement per se is the key to survival and growth in a changing world. 'Adaptability' as a concept is easy to support. As an operational philosophy it is not so easy to implement. As a goal for planning, it is much harder to quantify. A fixed scenario of a future world may provide helpful guidelines, but a scenario that demands adaptability to an uncertain future world is much less definite. Of course, everyone else in the world is also uncertain about the future, and they are making their plans using different assumptions. This virtually guarantees that our future will turn out different to our expectations. This is in part what Hayek (1945) calls the 'knowledge' problem. Until now, most of the planning and technical research undertaken in the world has ignored this problem. This ignorance is a luxury that we can no longer afford. The paper looks at the history of technological change and highlights the characteristics of successful technological revolutions. 'Adaptability' to unforeseen circumstances is the key to success in this environment. The paper examines the knowledge problem from the perspective of the mineral industry, and suggests a number of directions for maximising the returns from application of computer technology in this important area.

Jan 1, 1995

By Watson D. F

P S B Stewart has rightly pointed to a possible obscurity in our paper on drilling patterns, viz. in comparing the improvement of a triangular drilling pattern over a square one, we used percentage improvements without always making clear their base. We hope, however, that other readers, like Stewart, have been able to understand the particular meaning from the context.Although different methods of estimation of an ore deposit will have different local bias (Philip and Watson, 1985), the critical relationship affecting the reliability of estimation of an unsampled location is the scale of local variation of the variable being estimated in comparison with the density and isotropy of sampling. This relationship overrides all other considerations.

Jan 1, 1985

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 Boehme PW, Gregory OR

The results presented here show quite definitely that in the system investigated the intensity of dispersion is enhanced by switching the flow entry from bottom to sides of the packed trough. Since there is no reason to suppose that this would not be true generally then it is not surprising that the blast furnace dispersion data of Standish and Polthier lie above the data for packed columns with bottom fluid entry. In fact, on the basis of the present results, blast furnace dispersion results can never equal standard packed column behaviour but must always be above these. The result that the intensity of dispersion in the trough model is higher closer to the side ports than away from them is at variance with that of Standish and Polthier blast furnace results. Aside from the obvious structural differences between these two systems, it is thought that the presence of raceways and the tortuous path of the gas flow in the furnace may provide an answer. Clearly this is an important difference in the behaviour of the two systems and further investigations designed to clarify the position would have significant practical value. This would also give an indication of how the furnace D/ud values may be decreased along the whole height - assuming of course that this result gives the best overall performance of the furnace. However, there is to date no knowledge whatsoever about this aspect of blast furnace Technology.

Jan 1, 1975

By A Muhairini, M Eggers, J Smith, H Baxter

Detailed geochemical analysis of cored and non-cored drill hole data was used to characterise and model the Cenozoic detrital valleys of several deposits within the southern Pilbara region, Western Australia. The purpose of this modelling was to better characterise and understand the relationships between the various geotechnical units comprising mixtures of rock and soil for the purposes of slope stability and depressurisation studies.This paper presents data from several valleys where geological, geomorphological and climatic processes have resulted in the deposition of heterogeneous detrital rock and soil sequences. Seven primary detrital units are recognised as occurring within all the valleys studied, suggesting that the geological processes involved in the erosion and deposition of the units were widespread. Geochemical assessment of cored and non-cored data suggests correlatable geochemical signatures can be recognised for each of the units; however, local variability in the groundwater history of individual valleys is demonstrated by late-stage carbonate precipitation recognised both in the core and through the geochemical signatures, which has resulted in alteration of the parent rock/soil material. This paper discusses how the carbonate alteration may lead to improvements in rock/soil mass strength of a clay unit by comparing laboratory strength test samples of the same parent material with varying degrees of precipitate alteration to those with no discernible carbonate alteration. Following from this, correlations with geochemical assay results have been derived, whereby zones of more favourable strength conditions may be modelled through assessing areas of analogous geochemistry.The paper demonstrates how geochemical assessment can lead to improved geotechnical and hydrological modelling for a detrital valley system without the need for significant coring and laboratory testing. This in turn leads to improved confidence in the slope design and depressurisation recommendations for a slope.CITATION:Baxter, H, Eggers, M, Muhairini, A and Smith, J, 2015. The effect of carbonate alteration on detrital mass strength and implications for geotechnical slope design, in Proceedings Iron Ore 2015, pp 429–436 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By J Player, P Evans, G Sweby

Achieving quick underground access after the completion of an open pit mine can be critical to maintaining project value and ensuring regular ore feed to the mill. This paper outlines the design and construction for two portals in an active open pit to commence underground development quickly whilst installing appropriate ground control to maintain long term access in an uncertain setting. Implementation of the portal designs was complicated by the change in underground design from hangingwall access to footwall access late in the life of the open pit due to preferable ground conditions. The portal locations did not have easy access for ground support installation integrated into the pit design due to the timing of the underground design changes. Practical implementation of the ground support systems subsequently became a key part of the project. Intact rock strength, rock mass characteristics, gradational weathering / alteration profile and structural information were modelled against pit displacement monitoring as the basis from which the portals were located and ground support schemes designed. Conditions around one of the portals necessitated numerical modelling to estimate the appropriate level of ground control for long term stability. The design was completed whilst the open pit was actively on-going and the portal areas not entirely exposed. The rock mass assessment and analysis for the two portals indicated different ground support scheme capacities would be required. The expected level of control for one of the portals also necessitated the use of monitoring with extensometers and load cells to ensure the rock mass response and ground support scheme performed as planned. Construction of the portals demonstrates the benefit of a considered design process, a plan which allows practical installation of ground support schemes where access is limited, the benefit of ongoing monitoring to ensure performance remains within design limits and the challenges involved working within an active pit with limited floor space.

Mar 15, 2021

By Campbell R

The use of a 35mm non-metric SLR camera and an analytical plotter to prepare close range photogrammetric (CRP) plans of a quarry and open pit mine face is described. The plans, at scales ranging from 1:5 -1:1 000, were used to measure the orientation of geological structures and failure surfaces in the exposed faces.Details are provided on the equipment used and the field techniques. The method:ò is quick and relatively cheap to perform,ò allows the accurate orientation of specific geological features to be determined,ò provides survey results of suitable accuracy that may be used for detailed geotechnical analyses of pit wall failures,ò shows great potential as a rapid and accurate technique for monitoring changes in pit wall profiles with time.

Jan 1, 1990

By Y D. Jeon, K S. Kim, C-H Eom, C M. Yoon

The carbon neutrality continues to require reduction of carbon usage in ironmaking and steelmaking processes. Specially, it is expected that the hot metal ratio (HMR) in the steelmaking process should be reduced essentially. Unfortunately, the reduction of the HMR in converter can bring about poor environment for nitrogen removal from molten Fe. From this situation, nitrogen prediction model has been developed to understand the fundamental of behaviour of nitrogen and quantitatively interpret its content changes in the converter process. Thermodynamic and kinetic approaches were improved based on existing mathematical model and attempted to predict nitrogen content in realtime by combining process data. In present study, heat supply from the oxidation (mainly carbon and silicon) and CO evolution in the converter are considered, and scrap melting due to the heat transfer from the molten Fe to the solid scrap charged in the converter also be considered.

Aug 21, 2024

By Arumba J

In the Mount Victor area of the Eastern Highlands Province, re- connaissance geological mapping and new micropalaeontological data have revealed the existence of at least three small thrust- bound windows exposing late Middle to Late Cretaceous (Late Aptian-Early Albian and Late Santonian-Maastrichtian) sedimen- tary rocks and pillow lavas, Latest Paleocene- Earliest Eocene pillow lavas, and Latest Paleocene-Earliest Eocene bathyal micrites. Late Middle Eocene to Late Eocene inner neritic bioclastic micrite units also occurs in thrust contact with Middle Miocene Yaveufa Formation volcanolithic conglomerates. The Cretaceous and Early Tertiary units appear to be thrust-bound and are best exposed in a window just south of Mount Victor, and in two smaller windows to the east. The inner neritic Eocene limestone occurs in a thrust-bound sliver within the Yaveufa For- mation near Obura. The windows occur within extensive out- crop of Early Miocene Omaura Formation and the Yaveufa For- mation. Thin-bedded grey mudstone, siltstone and sandstone, typical of much of the Chim Formation form only a small part of the exposure of Cretaceous rocks. Thick-bedded volcanolithic conglomerate, spilitic pillow basalts, and welded basic tuffs domi- nate the Cretaceous section. The stratigraphy and structure of the Mount Victor area is similar to the Menyamya area, the Aure Scarp, and perhaps the Tapini area. This study has raised the possibility of widespread thrust- ing in the Kainantu area, and suggests that the boundary between the Omaura and Yaveufa Formations is thrusted, at least locally.

Jan 1, 1997

This paper describes the application of a three-dimensional finite element modelling tool to help assess the stability of a highwall at a Central Queensland mine following the weakening of its base due to highwall mining. With traditional stability assessment techniques, likely failure modes are identified on the basis of previous experience and structural, sedimentological and geomechanical data and a mechanistic analysis of these individual modes is performed. The value of the full three-dimensional model over these traditional techniques is that it provides a coherent approach to assessing highwall stability without the necessity of initially deciding upon the dominant failure mechanism and gives a useful adjunct to the traditional tools. The three-dimensional model assumes the rock mass is made of elasto-plastic blocks, incorporating possible planes of weakness, separated by near horizontal joints. The model includes the relaxation of stresses due to the excavation of the highwall and incorporates estimates of blast damage near the highwall surface

Jan 1, 1995

By Ichinose M, Tsuru T, Gotoh K

Since 1980, the Department of Mining Engineering at Kyushu University, in co-operation with the Ikeshima Colliery, Matsushima Coal Mining Co. Ltd., has been conducting a research project into longwall gateroad designs applicable to deep and poor strata conditions. During this period, the economic environment has drastically changed the situation of the domestic coal mining industry. Conventionally, the retreat longwall method, with re-use of gateroad, has been employed as it achieves higher recovery. However, from the view point of production efficiency, this method is not suitable because it requires intensive work in side packing and roadway maintenance. Therefore an interpanel-pillar system, or a two-entry gateroad system, was adopted to identify the factors responsible for excessive vertical closure in longwall gateroads. Field measurements and non-linear finite element analyses were undertaken to confirm the performance of this system. Study results indicate that the stability of the gateroad employing the rib pillar system is comparable to that of the conventional system of re-using Gateroads.

Jan 1, 1992

By J D. Lubben

Hibbing Taconite is a Lake Superior-type granular magnetite taconite deposit occurring within the Biwabik Iron Formation along Minnesota’s central Mesabi Iron Range. The deposit is situated on the northern margin of the Proterozoic Animikie Basin. The deposit strikes northeast, dips gently southeast, and occupies 10 km of strike length. Mining focuses on 50 m of granular cherty and laminated slaty taconite within the Lower Cherty member.Ores generally consist of a quartz, magnetite, siderite, ankerite, minnesotaite, stilpnomelane, and haematite mineral assemblage. Processing is optimised by exploiting the physical and chemical variations that exist between three major ore types. Taconite ore averages 20 per cent magnetic iron (MagFe), 27 per cent weight recovery (WtRec) and produces a final concentrate with 4.5 per cent silica (SiO2). Since 1976, production has totalled approximately 237 million long tons (Mlt) of pellets (8 Mlt per year rated capacity).Ore processing uses a simple fl ow sheet of autogenous grinding (<0.044 mm) followed by two phases of wet magnetic separation, fi ltering, limestone/bentonite addition, balling, and firing to create pellets averaging 66 per cent total iron. A Liberation Index (LIS) is used as a primary guide for ore grading and metallurgical control. Grind requirements, magnetite liberation and silica grade are closely monitored to ensure plant optimisation and product quality.A recent program of benefi ciation of low-grade ores by in-pit crushing and dry magnetic cobbing has demonstrated that low-grade ores (<17 per cent MagFe, <25 per cent WtRec) can achieve a signifi cant metallurgical upgrade (up to 25 per cent MagFe and 40 per cent WtRec). This operation recovers 60 per cent of the total crushed volume, and has a calculated effi ciency factor (magnetic iron recovery) of 79 per cent. This paper discusses the benefi ts of this upgrading and its effects on ore blending and processing.

Jul 11, 2011

By J A Evans

A well-maintained and low cost mining operation today requires the use of condition monitoring techniques. At ERA - Ranger Mine oil analysis, vibration monitoring, infra-red themtography, and performance analysis have been successfully applied over the last four years to lower operating and maintenance costs. All condition monitoring is scheduled through a comprehensive in-house developed maintenance management system known as the Engineering Information System (EIS). (EIS) is used extensively at Ranger to ensure consistent frequency and recording .of all condition monitoring data. This paper provides an insight into the benefits of condition monitoring and explores the future direction for condition monitoring techniques at Ranger.

Jan 1, 1994

By R Wilson, S Luke, R Williams, B Freeburn

"In 2010, two McLanahan RSS14×50 scrubber screens were installed at Fortescue Metals Group’s (Fortescue) Christmas Creek site. By 2015, the trommel (screen) section had effectively reached the end of their serviceable life. This was determined by regular measurement of structural components over the previous 18 months that tracked wear life. At the same time, numerous trials and optimisations had taken place on screen panel design and material composition. During 2015, a new set of trommels were designed, manufactured and installed that incorporated many new features: increased open area to facilitate high throughput, improved wear protection for structural members, simplified trommel panels and realigned discharge ports to reduce wear on exit. Numerous other upgrades have taken place on the drive system, feed chutes, liner and weir configurations and park brake, to name a few. This paper will highlight how regular measurement drove design changes and how the site and the original equipment manufacturer (OEM) managed a replacement program that has delivered improved performance.Citation:Wilson, R, Luke, S, Freeburn, B and Williams, R, 2016. Regular Measurement Defines Upgrades on Scrubber Screens, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 285–290 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016