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By Kwitko G

Exploration for coal has been on-going in South Australia for the past 100 years. During this period substantial resources of low rank coal have been delineated throughout the State. These deposits are of variable quality often with high moisture, sodium, chlorine, sulphur and ash content and although generally regarded as suitable for use in conventional pulverised fuel boilers, many are difficult to utilise. The only operating coal mine in South Australia is at Leigh Creek where coal bearing shale was discovered by chance in 1888 during excavation of a railway dam near the township of Copley. Leigh Creek has had a very diverse mining history from the initial small scale underground mining through to open-cut mining utilising draglines and more recently large shovels and trucks.

Jan 1, 1992

By L Keeney

Geometallurgy is not a mechanism designed to replace current geological and metallurgical deposit characterisation but an added component required to understand orebody variability. Current geological characterisation approaches focus on understanding deposit genesis aimed at identifying new mineralised regions and metallurgical characterisation determines parameters required for engineering design of processing plants. Geometallurgical integration has the task of drawing on aspects of each stream to enable spatial mapping of performance indices across a deposit. It is a complimentary activity to current practice and adds a new dimension to orebody knowledge. Although the notion of conducting an integrated geological and metallurgical analysis is not a new concept, limited publications exist in the field proposing integrated methods, with several technical issues existing in current geometallurgical integration approaches. An iterative method drawing on existing geological and metallurgical characterisation and new measurement tools and inputs is proposed. The integrated method comprises of discrete components dynamically linked together through iterative feedback loops with each component having a specific purpose achieved by applying a range of data acquisition technologies and statistical tests. The key outcomes of the method are:overcoming the lack of optimised geometallurgical domains relevant to processing performance,development of a rigorous approach to identifying parameters controlling processability,improved protocols for relevant metallurgical test data and sample selection, andability to generate greater data support to enable rigorous geostatistical modelling of geometallurgical attributes. This paper outlines the integrated mapping and modelling method developed and draws on multiple data acquisition technologies applied within the AMIRA P843 GeMIII Project.

Sep 5, 2011

By J Bean

Iluka Resources Ltd developed the Jacinth-Ambrosia Mine (Jacinth) in the Eucla Basin during 2009 and 2010. In this arid climate the operation relies on hyper-saline groundwater from a palaeochannel for process and potable water supplies. The water is hyper-saline, acidic and mildly reducing, with high ferrous iron concentrations. Ferrolysis commences on exposure of water to oxygen, resulting in increased acidity and the conversion of dissolved ferrous iron to insoluble ferrihydrite. The unstable groundwater forces a careful balance between interventions relating to maintaining pipeline efficiency, corrosion protection and processing aspects. Providing an oxidising environment at the head of the pipeline will result in the precipitation of akaganenite and goethite in the pipeline, which over time reduces pipeline efficiency. However, sending too much ferrous iron forward may reduce processing performance.The processing plant experiences changes in water chemistry in response to the variability of iron concentrations and pH within the pipeline, and the spatial and chemical variability of ore. As the main orebody at Jacinth contains little buffering capacity a source of carbonate in the overburden is carefully used to allow the cost-effective control of process water pH.This paper highlights the importance of understanding the chemistry of saline make-up water, ore, and overburden when designing water treatment facilities and heavy mineral processing facilities.

Oct 5, 2011

By D R. Wines

The design of near-surface civil infrastructure requires detailed consideration of the geological/ geotechnical conditions, excavation geometry and sequence and ground support measures to ensure stability of the underground openings and minimal impact on overlying or adjacent infrastructure. Twin parallel road tunnels have been designed and built with connecting cross passages and a piggyback busway tunnel as part of a large infrastructure project in Australia. The tunnels were excavated in poor to fair quality rocks using road headers. Temporary ground support includes shotcrete, rock bolts and canopy tubes. Extensive numerical analyses have been performed to analyse the expected behaviour of the tunnels during excavation, including two-dimensional analyses using UDEC and three-dimensional analyses using FLAC3D. Structural defects in the rock are explicitly included in the 2D analyses to examine the potential for localised ground instability. The stress redistribution is captured by the 3D modelling with an accurate representation of the complex excavation geometry and the detailed excavation and support sequence. This paper presents the modelling methodology, numerical results and discussions on integrating both 2D and 3D analyses to achieve reasonable design.

Mar 8, 2011

By C Fountain

Australian mining and engineering companies have increasingly been investing in the mining industry in Brazil. It is a country of enormous mineral and agricultural wealth, with a well-established mining sector. Some Brazilian mining companies and personnel have been journeying in the opposite direction. There are significant differences in the approaches to engineering between the Australian and Brazilian industries that can cause confusion for companies operating in the other country. These range from differing expectations during the various stages of feasibility studies to style of plant and contracting strategies during the construction phase of projects. Some of the differences are driven by tax regimes, labour costs, or different settlement patterns. Others are the result of different histories and pressures on the industries in the two nations.This paper describes some of the differences in approach found in the two countries and some of the reasons for them.

Aug 8, 2011

By D MacKay

The Mt Wright Project is located near the town of Ravenswood in North Queensland and is operated by Carpentaria Gold – a wholly owned subsidiary of Resolute Mining Limited. Underground Development of the current Mt Wright orebody commenced in June 2006 and the first production ore was brought to surface in June 2007. The orebody is a rhyolite pipe containing fine-grained disseminated gold in a granite host rock. Ground conditions tend to be good to excellent throughout development, with some minor deformation experienced when stope-sized excavations are formed. The mine commenced as a sublevel open stoping (SLOS) operation with the intent to utilise development waste to back fill isolated upper level stopes while developing to the bottom of the known orebody. The mine plan intended to commence production with a bottom-up primary/secondary stoping retreat through the main orebody utilising cemented fill. Some challenges were faced during the initial production phase that included:•Ongoing underground diamond drilling and updating of the block model resulted in some issues reconciling the grade control results to the resource model. This was primarily due to the high variability of grade which in turn caused difficulties in accurately identifying areas of low and high-grade.•The cost of establishing and operating a cemented fill plant to achieve the planned extraction sequence of the orebody had increased significantly beyond initial estimations.•Geotechnical conditions such as stress orientations, ground behavior and response to the forming of excavations learned through the mining of the upper level stopes were different to the assumptions made during the initial design.A number of in-house and external reviews of the mining method were completed which has resulted in a revised mining plan. This paper will summarise the challenges faced and the implementation of the mine plan to date.

Mar 21, 2011

By W. M. LONIE

Address by the President of the Institute (Mr W M Lonie) in making the presentation of the Certificate of Honorary Membership to Sir Ian McLellan, K.C.G.M, K.B.E. Address by Sir Ian McLellan after accepting the award.

Jan 1, 1979

By J Shandro

This paper stems from recent multidisciplinary research between mining engineering and health researchers at the University of British Columbia and the University of Victoria, Canada. It considers the implications of a future state of sustainable mining development that places more emphasis on consideration of mine community health and sustainability within the definition of mine planning best practice. It reviews recently completed research studies on mining and other resource communities in British Columbia, Canada and a process undertaken by the research team to share research findings. It then examines the outcomes of this knowledge sharing process placing emphasis on the development of a more collaborative and enhanced mine planning process that integrates community- level indicators of health and sustainability to more effectively address mine impact-benefits. The paper concludes by discussing current initiatives that aim to benefit the mining industry, communities, and governments as they plan future mineral development projects.

Nov 22, 2011

By Butler I. K, Nicholson P. M

There are four main types of base metal and gold mineralisation recognised in the central Pine Creek Geosyncline. These are stratiform, polymetallic veins, stockwork/concordant gold-quartz veins and unconformity related uranium-gold-platinoid mineralisation. The stratigraphy of the central Palaeoproterozoic Pine Creek Geosyncline has been simplified into three groups comprising the Batchelor, Frances Creek and Finniss River Groups in ascending order. Stratiform mineralisation occurs within the Frances Creek Group. The earliest mineralisation is found adjacent to circular faults ringing basement highs. Higher in the stratigraphy, stratiform mineralisation is often associated with zones of high compression in the vicinity of basement highs. A synsedimentary-diagenetic origin for stratiform mineralisation is proposed. Polymetallic vein mineralisation occurs within the Frances Creek and Finniss River Groups. Its composition changes systematically through the stratigraphy similar to the stratiform mineralisation. The mineralisation is structurally controlled and usually occurs in the vicinity of basement highs. Stockwork-concordant gold-quartz vein mineralisation is hosted by the upper Frances Creek and Finniss River Groups. It occurs within compressional zones and along the Pine Creek Structure corridor around, above and particularly between basement highs. Mineable reserves occur in thick continuous semi concordant quartz-sulphide veins and/or stockworks. Unconformity related uranium-gold-platinoid mineralisation shows a close spatial relationship with the Palaeoproterozoic/Mesoproterozoic unconformity. The mineralisation is localised by structures formed during Mesoproterozoic deposition and is commonly adjacent to Archaean basement or its remobilised equivalents. The type of mineralisation (stratifom/polymetallic vein) is a reflection of local stress regimes, structure and physio-chemical conditions. An initial phase of stratiform mineralisation is postulated to have occurred with the first significant marine transgression in a tensional regime. A second phase occurred later during a compressive regime. "Ihermochemical sulphate reduction of mineralising fluids by hydrocarbons is invoked as the precipitation mechanism for the polymetallic vein type of mineralisation. Hydrocarbon generation is postulated to have occurred within the Frances Creek Group, in many places contemporaneously with the movement of mineralising fluids and basin compression. Polymetallic veins formed from the interaction of mineralising fluids and hydrocarbons which were trapped in suitable structures. An abundant, continuing supply of hydrocarbons was necessary to form significant deposits. Where these conditions were not net, the mineralising fluids largely continued their ascent to the near surface environment to form stratiform deposits. The stockwork/concordant gold-quartz vein mineralisation is a later event and occurred during the relaxation of compressional defonnation after deposition of the 1-inniss River Group.

Jan 1, 1994

By A Fowler

The unpredictability of the location, grade and width of narrow-vein deposits presents difficulties for mine geologists and engineers attempting to estimate, schedule, forecast and mine their deposit profitably. This unpredictability stems not only from the grade distribution within a vein, but also the irregularity of vein geometry in three-dimensional (3D) space. Traditional deterministic methods of modelling vein geometry do not account for the inherent variability of the veins, resulting in significant errors when using limited drill hole information. This paper presents a probabilistic method of modelling narrow-vein deposits using sequential gaussian simulation (SGS), which can quantify this variability and improve production forecasts. Vein geometry, thickness and grade are simulated to provide a number of different equi-probable realisations that each honour the drill hole and face sample input statistics. An example is presented from the Augusta narrow-vein Au-Sb mine in central Victoria, where the simulation results are validated against the input data and survey pick-ups of the veins along ore drives.

Aug 22, 2011

By B Taylor

The Perseverance deposit is the most southerly known economic copper/gold deposit within the Cobar gold field. The deposit is situated approximately 12 km to the south-southeast of Cobar and is essentially blind to surface with the top of economic mineralisation occurring 750 m below ground level.Based on the December 2010 resource estimate (inclusive of reserves and net of depletion) the deposit contains 3 011 000 tonnes at 6.1 g/t Au and 0.90 per cent Cu (590 000 oz of gold and 28 000 tonnes of copper). The deposit is comprised of four principal lenses, the Perseverance, Hulk, Zone B, and Hercules lenses. In excess of 90 per cent of the known resource tonnes are contained within the Perseverance and Hulk lenses. The deposit is shear related and hosted within lower Devonian rocks of the Cobar Basin. The competency contrast of rhyolites juxtaposed against sediments by the Peak-Perseverance shear is the principal control on mineralisation. Both the Perseverance and Hulk lenses are primarily hosted by brecciated rhyolites juxtaposed against Chesney formation sediments across the Peak-Perseverance shear. This faulted rhyolite sediment contact roughly defines the global orientation of the deposit. The Perseverance lens continues within the shear for up to several hundred metres beyond the extent of the faulted rhyolite sediment contact. Mineralisation within the shear beyond the faulted rhyolite contact zone is hosted by sheared silicified sediments. The Perseverance lens remains open at depth and to the south.The Zone B and Hercules lenses, which are significantly less important in tonnage terms, are hosted by rhyolite breccias within the main body of the rhyolite and appear to be only tenuously related to the Peak-Perseverance shear. Within the Perseverance lens, the presence of northeast trending high grade breccia veins developed oblique to the north-south trending shear system has led to the development of steeply north plunging high grade ore shoots within a globally north-south trending mineralised domain. These high grade shoots have limited horizontal continuity but significant down plunge extent.The presence of coarse gold and the resulting strongly skewed nature of the gold grades, in conjunction with controls on mineralisation which are not parallel to the mineralised domain, has led to predictive difficulties regarding stope performance.Strong heterogeneity of the gold content of the ore and geological controls on mineralisation which are not parallel to the global trend of the mineralisation impose a set of difficulties which sound geological control is helping overcome.

Aug 22, 2011

By P G. Greenhill

The Wonawinta silver project near Cobar in NSW is under development by Cobar Consolidated Resources Limited (CCR). RMDSTEM Limited is part of the owner’s team for feasibility, design, engineering, construction and commissioning.With a 51Moz resource CCR is one of the largest pure silver players in Australia. A probable reserve of 14.3Moz has been defined for a mine life of approximately five years. The silver mineralization is contained in host rock composed of clays and oxidized limestone. The ore also contains on average 1.3% lead as cerussite, and other minerals. A simple circuit consisting of slurrying of the ore, gravity treatment of the coarse fraction to recover lead, silver extraction using CIL, elution and the Merrill Crowe silver recovery process, has been developed.The “value engineering” approach to this development pioneered over the past decade by RMDSTEM has meant that RMDSTEM has delivered the bankable feasibility study at a cost of $0.07 per resource ounce. It is highly cost effective making efficient use of shareholders funds as well as being very time efficient. This paper describes the application of the value engineering approach to the development of the Wonawinta project.

Aug 8, 2011

The Sishen iron-ore-mine produces 3 pro= ducts with size gradings of 25 to 8 mm, 11 to 5 mm and 5 to 0,2 mm and has a product capacity of 20 Mtpa. Ore is produced at an average Fe content of 66,2 % Fe for the two coarser pro= ducts and an average of 65,3 % Fe for the fine ore product. Three stage crushing is practised to re= duce the run-of-mine ore to -90 mm after which it is screened into five different size frac= tions of which four are heavy media beneficiated in static baths and cyclones and the fifth frac= tion discarded to slimes dams. A final three stage crushing and screening process is employed to produce the final three Products which are homogenized by means of blen=ding systems nrinr to despatch.

Jan 1, 1987

By Z Fu, E Topal, O Erten

"Mine waste rock management involving waste rock movement and placement, is a critical aspect in the planning of open pit mining operations, as the waste rock haulage cost can be the largest portion of the mine operating cost. The concept of sustainable development in the mining industry also encourages environmentally friendly waste dumps that have zero hazards to people and the surrounding environment. Therefore, a detailed waste management schedule must satisfy economic and environmental considerations. However, the available tools in the market cannot provide optimal waste dumping schedules to meet all these constraints. This paper introduces a user-friendly and automatic tool to optimise the waste dumping schedule, which minimises the haulage cost, and covers the encapsulation of reactive materials to minimise acid mine drainage problems. This tool has been developed by using a new mixed integer programming (MIP) mathematical model that considers both single-lift and multilift dumping scenarios. The application of the proposed tool on a data set collected from a gold mine shows that the multilift dumping scenario has provided a more flexible and economical waste dumping schedule than the single-lift scenario, and both scenarios satisfy environmental requirements.Citation:Fu, Z, Topal, E and Erten, O, 2016. A Modified Software Tool for Mine Waste Rock Dump Planning, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 229–242 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By B Clements, R Dunne, J Dioses, S Hart

In April 2003 plant upgrades in the æLow GradeÆ Cadia Hill circuit were undertaken in order to improve concentrate quality and metal recoveries from the flotation circuit. The major changes involved: circuit reconfiguration to allow all concentrates to be reground to less than 38 ¦m prior to final cleaning; increasing ball charge in the regrind mill to fully utilise all of the installed power; desliming of the cleaner scavenger concentrate to improve the circuit water balance; and the inclusion of a gravity concentrator in the regrind circuit to recover more free gold to bullion.Once the flotation circuit had stabilised under the new operating conditions concentrate launder modifications and increased froth crowding on the scavenger flotation cells permitted the introduction of stronger collectors without compromising concentrate quality or circuit stability.Twelve months on, the copper concentrate grade has increased by two per cent and metal recoveries increased by three per cent and seven per cent for copper and gold respectively. The project capital outlay of approximately $2.0 million has been repaid in less than three months. This paper will review the project from the design, construction and commissioning perspective as well as the subsequent debottlenecking exercise that was required to eventually yield the full benefits of this upgrade.

Jan 1, 2005

By C Parihar, R Garg, A Bhandari, S Bhandari

Blasting can impact the efficiency of entire downstream mining operation. Individual technology solutions for blasting have been available in the industry for many years but all of them only cater for certain aspects of blasting. Many of them are based on individual research and/or experiences. Some of the available software solutions are not suitable to be used in the field as that they need advanced skills or tools. Also, most do not take technology advancements like mobility, advanced data analytics, web solutions and integration into consideration. Hence, no technology platform is currently present in the industry that addresses all potential needs a blaster may need in an integrated manner.This paper presents an integrated solution that takes care of all aspects of blasting – design blasts according to mine plan; collect data after drilling has been carried out (as there is often difference in designed and actual drilled hole locations in the field); predict blast results in terms of fragmentation, flyrock, ground and air vibrations, wave front reinforcement and flyrock distance; and after assessment, allows changes in charging, delay timing and sequence. The technology solution is a secure, cloud-hosted, web-based software-as-a-service solution that can be accessed from anywhere. Also it has a mobile app, which is available for both Android and iPhone/iPad. The mobile app is also integrated with the web-based solution using application programming interface calls to the central data repository.Case studies for two limestone mines are presented where this solution is being used in its initial format. This software platform enabled analysis of the outcome from a previous blast pattern and then subsequently allowed optimisation of blasting operations based on historical data. Uses of this platform have resulted in improved key performance indicators in these two limestone mines. The mobile app as part of this platform enables extensive field blast data capture and analysis and also various predictions before a blast. Data collected include blast parameters, individual hole charging, initiation pattern, videos, photographs and vibration records for analysis/reporting. The key features of the solution are a blast designer, a detailed blast data collection/analysis and a series of environmental predictors. These predictors give blast results in terms of fragmentation, flyrock, ground and air vibrations and wave front reinforcement and take remedial steps before blasting to optimise and control adverse environmental impact. Many features, such as fragmentation predictor and mobility solution, are completely unique features that are not available elsewhere in such a field personnel-friendly manner.CITATION:Bhandari, S, Parihar, C, Garg, R and Bhandari, A, 2015. An integrated technology solution for optimised and environmentally-controlled blasts, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 393–400 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By D T. Ribeiro, J F. C L Costa, J C. Koppe

Drilling and sampling are responsible for most of the costs during mineral exploration, especially in multi-elements and polymetallic deposits, such as iron, manganese and bauxite deposits. On these deposits, often it is necessary to estimate multiple attributes at several granulometric fractions, ie distinct particle sizes. This paper investigates the effect of sampling at a close spacing grid only the head grades for the multiple chemical species in iron ore deposits. The remaining required data at the various grain sizes are sampled at a sparse grid. The derived geological model is checked for precision and accuracy comparing the output obtained against a model obtained using a complete isotopic data set including head grades and chemical analysis at each granulometric fraction analysed at all sampled positions. Among the several tested alternatives, the best procedure for dealing with the posed problem involved utilising the correlation coefficients between the grades at distinct fractions to obtain an isotopic database prior to interpolation. Cokriging was the method used, based on the intrinsic coregionalisation model. Estimates were obtained with the quality needed for the proposal of the study. Results showed that at least 50 per cent of the blocks were estimated with errors less than ten per cent relative to the grades obtained at the reference model, using only 15 per cent of the granulochemical data employed to obtain the reference model. The methodology also preserved the correlations between the attributes in their several granulometric fractions on the estimated model.

Sep 26, 2011

The optimal production of the metals needed by society is best achieved by a close synergy between concentrate production and smelting. For over 75 years commencing in 1923, such a close relationship was enjoyed between the Sullivan Mine in Kimberley, British Columbia and the Trail zinc-lead complex. An effective program of continual change and improvement at the Sullivan concentrator was achieved through a strong entrepreneurial spirit. This spirit was in part maintained through a favourable location in south-eastern British Columbia that resulted in a dynamic local community that has survived the closure of the mine. Innovations to be reviewed include feed forward reagent control, the use of column flotation to zinc and lead cleaning and the application of ultrafine grinding coupled with concentrate dewatering using hyperbaric filter technology.

Jan 1, 2005

By K Faure

At Sams Creek a peralkaline granite porphyry dyke hosts gold-bearing sulfide-quartz-siderite veins. The granite dyke intrudes Ordovician-Silurian metapelite and quartzite, and has thin lamprophyre dykes along its contacts. The mineralised veins and the granite and lamprophyre dykes have been deformed during several phases of folding, the youngest of which is Early Cretaceous. The granite has been hydrothermally altered, with early magnetite-siderite¦biotite alteration overprinted by sulfide and quartz-siderite veins and quartz-perthite-albitesiderite-pyrite-rutile¦sericite alteration assemblages. The sulfide veins are composed of arsenopyrite + pyrite ¦ gold ¦ galena ¦ sphalerite ¦ chalcopyrite ¦ pyrrhotite ¦ graphite, with minor quartz and siderite. The gold contains significant silver (up to 30.8 wt per cent) and ranges in fineness from 692 to 844. Immiscible liquid-rich fluid inclusions, in quartz protected from recrystallisation by enclosing arsenopyrite, contain carbonic liquid that homogenised at temperatures of 320 - 355¦C. The Sams Creek gold deposit is distinguished from the orogenic gold deposit type by its stockwork veining, magnetite-siderite¦biotite alteration, high sulfide content, ore mineralogy and the absence of mineralisation in the metapelite country rocks. Features of the Sams Creek gold deposit do not fit neatly into existing classifications of granite-related gold-bearing deposits. The peralkaline composition of the Sams Creek granite and the absence of molybdenite and paucity of chalcopyrite, are major points of difference with gold-rich porphyry copper deposits. The presence of a lowsulf idation-state ore mineral assemblage, carbonate alteration and carbonic fluid inclusions at Sams Creek are typical of many of the reduced granitic intrusion-related type of gold deposit. However, notable differences are: the reduced type granites are metaluminous and calc-alkaline; and Sams Creek only has high As in contrast to elevated Bi, W, As, Mo, Te, and Sb in the reduced type. The Sams Creek deposit also shows affinities with gold deposits associated with alkaline magmatism, and it appears to be a new variant of this type as an As-Au deposit associated with a peralkaline granite and lamprophyre.

Jan 1, 2004

By P J. Vardon, L A. van Paassen, Y Yao, A F. van Tol

Thin-lift atmospheric fine drying (AFD) is a technique used to dewater mine and oil sand tailings, which utilises both self-weight consolidation and atmospheric evaporation. The disposed layers undergo a cyclic drying and rewetting process due to precipitation and deposition of additional lifts on top of the dried layer. The current research aims to optimise the deposition process via use of a numerical model and realistic atmospheric conditions, including both periods of drying and wetting. The model is based upon water balance and includes large strain considerations. A number of material behaviours are characterised using empirical fitting curves based upon laboratory measurement of material characteristics, including both the shrinkage and water retention curves for drying and rewetting. The model is able to model multiple lifts, simulating field scale and realistic climatic conditions within timescales suitable for engineering practice (eg seconds or minutes). The model has been previously validated against controlled laboratory experiments and utilised to simulate field tests. A series of simulations are presented to illustrate the ability of the model to be used as a practical tool for the optimisation of a tailings deposition strategy.CITATION:Vardon, P J, Yao, Y, van Paassen, L A and van Tol, A F, 2015. The use of a large-strain drying and consolidation model to optimise multilift tailing deposits, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 263–270 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015