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The outcome of future metallogenic research will be important to everyone because it will. have a profound impact on our ability to find new deposits of non-reservable mineral resources. Failure to replenish our mineral stocks will threaten man's economic and social well-being, and it is vital that future directions of metallogenic research are considered carefully to ensure that research funds are applied wisely to underwrite our future.Today we are witnessing the declining phase of the era of easy exploration. The rate of discovery of shallow orebodies is slowing. This is very evident for base-metal deposits but is becoming increasingly apparent for gold deposits. The easy exploration era was marked by a heavy reliance on exploration techniques capable of directly detecting mineralization. These include simple prospecting methods as well as a host of geochemical and geophysical procedures and tools that enable explorers to pin-point regions' of mineralization within the upper couple of hundred metres of the Earth's crust. The role of

Jan 1, 1990

By Y Ren

The algorithms employed by the commercial tools are either heuristic algorithm or iterative optimisation of a subsystem. This often results in a suboptimal schedule. In this paper, the author presents a new scheduling algorithm that incorporates with a novel stockpile configuration system, an improved algorithm on multiple processes and a mixed-integer linear programming (MILP) global optimisation model. It can simultaneously optimise stockpiles, blending, multiple processes as well as multiple mines. In addition, it allows the user to interact with the solution to adjust the solution to be practical and desirable.CITATION:Ren, Y, 2013. A simultaneous optimisation tool for open pit mine scheduling, in Proceedings World Gold 2013 , pp 427-432 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By D E. G Connelly, K Y. Wong

Gold at the Harbour Lights Mine (HLM), WA occurs principally in pyrite (Py) and arsenopyrite (AsPy) minerals rendering it inaccessible to direct cyanidation. Froth flotation produces a concentrate with low mass recovery and with high recoveries of sulfides. After investigating several alternatives, a novel flotation process has been developed to separate the concentrate into pyrite and arsenopyrite rich fractions. The pyrite fraction is finely ground and cyanide leached, while the arsenopyrite is treated off-site. This paper describes the separation process from laboratory bench scale through to commercial operation at the HLM gold plant.

Jan 1, 2005

By Coates D. F, Neil T. J, O&apos

A proper economic analysis of pit slope design must reflect the trade-off between the benefits and the increased risks of slope fail- ure inherent in steeper slope angles. However, no formal framework for a proper analysis existed to date. This paper describes the results of the past four years' effort in which a formal eco- nomic analysis framework was developed and tested through a case study. This framework, in essence, consists of the availability of tested procedures and com- puter programs. The procedures as well as the programs are divided into two broad functional categories; (1) the first category related to assessing the economic benefits and costs associated with various pit slope angles and (2) the second category that determines the overall financial impact which the assessed benefits and costs exert to the mine operator's overall economic stature.

Jan 1, 1977

By S Roberston, G Batt, R Shanahan, B Shah, A Trench, H Bromfield

The geographic imperative of ore systems leaves mining, more so than virtually any other aspect of modern industry, heavily dependent on obtaining and maintaining social licence to operate. A prospective miner cannot arbitrarily walk away from a deposit in search of more favourable community perceptions – concentrations of mineral endowment represent highly specific and fixed elements of the landscape, and their development and extraction thus requires the acceptance and trust of a specific network of landholders and stakeholders, sometimes with diverse and even competing interests in the development and use of the local environment. Weakness or absence of such social licence can bring added costs and complexity to developing and operating a mine – and in extreme cases even result in project failure. Because it must be maintained throughout the life of a project, such social risk becomes a substantial part of overall project risk profile, particularly during routine operations once initial technical and development risks have been largely resolved.CITATION: Bromfield, H, Roberston, S, Shah, B, Shanahan, R, Trench, A and Batt, G, 2018. On equitable distribution of mining wealth and the social licence to operate imperative – an African case study, in Proceedings Complex Orebodies Conference 2018, pp 6–7 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

Techno-Economic Evaluation of a New Early Removal Process to Treat High-Arsenic Copper Ores

Sep 13, 2010

By D Giles, A C. Bailey

In the first 20 years of the 21st century, just over 20 per cent of Australian mineral exploration expenditure was dedicated to iron ore, totalling >A$8 billion and >30 million metres of drilling (Australian Bureau of Statistics, 2021). Improvements in the cost, efficiency, safety, reliability and data quality of drilling have the potential to deliver significant productivity improvements, increasing the probability of discovery and reducing the time from discovery to mining. Currently in its third year of research, Mineral Exploration Cooperative Research Centre (MinEx CRC) is focused on a new set of exploration tools and new ways to deploy those tools which recognise the fundamental importance of collecting quantity and quality data from the subsurface, to enable exploration success for all minerals, including iron ore. MinEx CRC is focused on developing more productive, safer and environmentally friendly drilling methods to discover and drill-out deposits. This includes pioneering work on Coil Tube (CT) drilling technology and innovations in Diamond and Reverse Circulation (RC) drilling techniques aimed at improved drilling optimisation and automation. In parallel, MinEx is developing new technologies for collecting data whilst drilling. This is being undertaken in four separate industry-led projects utilising geophysical, seismic, downhole analytical and 3-dimensional (3D) modelling improvements. A National Drilling Initiative (NDI) is also underway, with two drilling programs completed in 2020. The NDI is a world-first collaboration of Geological Surveys, researchers and industry, which undertakes drilling in under-explored areas of potential mineral wealth in Australia and provides a test-bed for new mineral exploration technologies.

Nov 8, 2021

By Potter DJ, Firkin GR

The Imperial Smelting Furnace operated by Sulphide Corporation Pty. Limited at its Cockle Creek zinc-lead smelter was recently equipped with tuyeres angled at 25 degrees instead of the usual 10 degrees. This change was prompted by the results of model studies undertaken by tha Research Department of Imperial Smelting Processes Limited, at Avonmouth in the United Kingdom, and by the favourable results of operating trials on the Cockle Creek furnace using bent-tip tuyeres to simulate 25 degree inclination. The use of 25 degree angle tuyeres has made it possible to operate with lower zinc values in discard slag and has improved hearth stability over a wider range of sinter quality and composition.

Jan 1, 1981

By V Gumba, S Narendranathan, C Barker, R D. H Thomas, G P. Bungard

This paper presents the positive outcomes on an EPCM project, which was undertaken in a challenging environment, whereby the design team had to generate a design with a number of stringent serviceability criteria, any deviation from which would have had significant implications to the proposed design performance. The success of the design implementation within the tight time frame hinged upon the precise installation by a skilled contractor. The overall objective was achieved as a result of close collaboration between the designer and contractor ensuring all stringent quality assurance/quality control (QA/QC) aspects were met and opportunities to optimise design without compromising on performance were identified and implemented, resulting in a cost saving of over A$13 M.CITATION:Narendranathan, S, Thomas, R D H, Bungard, G P, Gumba, V and Barker, C, 2012. The importance of collaboration between designers and contractors in implementing a design in challenging conditions, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 97-102 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By D Mather

Fibre reinforced shotcrete has long been accepted as temporary ground support in both mining and civil tunnel linings. Greater knowledge and understanding of shotcrete as an engineering material and advances in its quality have enabled designers to eliminate the requirement of a second pass lining. The initial shotcrete can be used as the permanent tunnel lining or be incorporated into the final lining design, rather than ignored and considered as sacrificial.For the initial shotcrete lining to become a suitable permanent tunnel lining it must be able to establish and maintain stability over time when subjected to all possible loads. To ensure this, best engineering practices are required during the design phase of the project to analyse; ground conditions including rock mass properties, ground and ground water quality, rock mass loadings, excavation sequencing, and construction methodologies.The increased durability of steel fibre reinforced shotcrete over traditional tunnel support, in the right ground conditions, makes it possible to achieve a serviceability design life of greater than 100 years (as required in most infrastructure projects). By specifying a good quality shotcrete mix and ensuring adequate quality control for batching, fibre dosing, preproduction testing, excavation sequencing, and application control, it is possible to eliminate the requirement of a secondary lining. The properties of a suitable permanent lining must be well established using suffi cient preproduction testing in combination with post application monitoring.A major benefit of steel fibre reinforced shotcrete in ground support applications is the removal of any requirement for workers to work under unsupported ground. Its use can also significantly reduce, if not eliminate, the manual handling associated with placing traditional reinforcement such as lattice girders and mesh. Both of these benefi ts are significant with the ever increasing focus on health and safety.This paper highlights factors that must be considered in the design and specifications to enable an initial shotcrete tunnel lining to become the permanent shotcrete tunnel lining.

Mar 8, 2011

By K Biegaj, S C. Dominy

A high-nugget effect and presence of coarse gold characterises many styles of gold mineralisation. The effective sampling of these deposits is often difficult because of the relatively low concentrations involved and erratic nature of the gold or other minerals. Geometric and/or metallurgical complexities often compound this effect. Underground development, in-fill drilling and bulk sampling/trial mining are generally required to delineate Ore Reserves. Similarly expensive definition strategies often apply to surface mining in complex orebodies of gold and other minerals, including precious stones. Development, particularly winzing is a historical technique that was used to gather geological, grade and metallurgical data during underground and near-surface exploration. It permits access to the mineralised structure below the surface datum to determine viability. Winzing has always been considered an arduous and dangerous task. Modern winzing technology has led to the development of the Mobile Supersucker – essentially a giant vacuum cleaner with underground and surface capabilities. By the elimination of shovel-loaded blasted winze material into a kibble and hoisting, this system permits safe and highly efficient winzing activities, and allows the collection of bulk samples for grade and metallurgical evaluation, as well as access to the mineralisation for geological and geotechnical mapping. Bulk samples from horizontal development have long been collected to help define mineable grade via pilot processing. However, when defining blocks below current development, there has been over-reliance on ineffective ‘small sample’ drill data. The Mobile Supersucker permits the development of winzes and off-winze sub-levels. These provide critical information to a mine technical team when trying to justify capital to go deeper or commence or deepen an existing open pit. CITATION: Biegaj, K and Dominy, S C, 2018. Lowering risk in complex mineralisation: application of mobile supersucker development, in Proceedings Complex Orebodies Conference 2018, pp 113–115 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

Thermal Processing of Petroleum Fly Ash for Vanadium Recovery

Sep 13, 2010

By J Rose, D O’Toole, D Grant

Orepasses are a critical element in the transport of ore from the stope drawpoint to the surface ore stockpile, making them an integral part of an underground mine’s ore-handling system. Well-designed and operated orepasses improve productivity and lower operating costs over a long period of time.The Olympic Dam mine, as part of a 6 Mt/a expansion project in 1997, constructed a large network of orepasses feeding a rail haulage system to facilitate the movement of approximately 8 Mt/a to the Clark crusher and hoisting shaft. The orepass network comprises 14 orepasses and currently includes 59 individual tip points. The orepass network has been in operation for over 15 years and in excess of 110 Mt of ore has been moved through the system.Olympic Dam’s management of mine infrastructure includes a program of assessing the condition of the Clark system orepasses. A comprehensive program was initiated in 2011 and consisted of systemically performing volumetric surveys to determine the integrity of the various sections of the orepasses. The current geometrical state of the orepasses provides essential information for comparison of geotechnical and operational parameters and a baseline for understanding the key causes of orepass deterioration to assist in the planning of both usage and potential replacement options.The collection of geotechnical and operating data allowed the review of the current condition, potential longevity and associated risks with the various orepass sections. Initial studies have also reviewed options for rehabilitation and/or replacement.CITATION:Rose, J, Grant, D and O’Toole, D, 2016. Orepass monitoring and management at Olympic Dam Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 609–616 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Falbo A, Barbaro M, Esposito MA, Passariello B

Acidic reductive leaching is one of the best known and most widely employed chemical processes for beneficiating minerals of industrial interest. Conventional acidic leaching with sodium dithionite (Na2S2O4), employed to bleach industrial minerals used in the production of ceramics, glassware, paper etc, does not always allow products of high quality to be obtained. In the work reported here two reducing agents, ascorbic acid and oxalic acid, have been employed in a medium acidified by means of sulphuric acid. Continuous systematic tests have been performed on a kaolin sample containing 0.8 per cent Fe2O3, adopting various operating parameters such as, leaching time, temperature and reagent concentration. In each case the total quantity of bi- and trivalent iron dissolved was ascertained. Removal of 80 per cent and 100 per cent of iron with ascorbic and oxalic acid respectively was obtained, while less than one per cent of iron was dissolved in the presence of sulphuric acid only. Products having a very good degree of whiteness (92 - 94 per cent) were obtained, whereas with sodium dithionite the degree of whiteness was in the 85 to 88 per cent range. The best conditions identified were applied to a sample of quartz for the removal of ferric impurities.

Jan 1, 1993

By J W Shields

The aim of this paper is to present a concept or model regarding a particular geological environment where gold orebodies occur in the Pine Creek Geosyncline and indeed in many other pans of the world. The name GIGIACS (an acronym for Gold In Greywacke In Anticlinal CrestS) is proposed to label this concept or model. The name Saddle Reefs (which has been in use for many years) is used for gold-bearing quartz veins which often occur in conjunction with Gigiacs. Simple patterns formed by this type of mineralisation at the surface due to different configurations are illustrated. Some examples of Gigiacs and associated saddle reefs are presented from the Pine Creek Geosyncline together with examples from other parts of the world. This concept has been used successfully as an exploration tool and five examples are given. The terms Gicsiacs (for Gold In Carbonaceous Shale In Anticlinal CrestS) and Giliacs (for Gold In Limestone In Anticlinal CrestS) are also used.

Jan 1, 1994

By Warren L. J

The recovery of phosphate minerals from the Mt Weld deposit by froth flotation has been studied by many researchers. Most of the flotation experiments were carried out with a tall oil fatty acid as collector and sodium silicate as dispersant and gangue depressant at pH about 10. Several rougher stages and cleaner stages and, sometimes, a desliming stage were included. The major difficulty was to reduce the Fe2O3 impurities in the concentrate to the required level. We used QEM*SEM (Quantitative Evaluation of Materials by Scanning Electron Microscopy) to provide a comprehensive and accurate mineralogical analysis of the flotation products. The analysis indicated that the Fe2O3 impurities were mainly recovered in the second concentrate, owing partly to the incomplete depression of the liberated iron oxides by the sodium silicate and partly to composite particles containing iron oxides. The selective depressing action of sodium silicate was improved by adjusting the variables such as the modulus (SiO2/Na2O), pH and time of standing of the stock sodium silicate solutions or by adding some polyvalent metal salts into sodium silicate solution. The flotation process was optimised to produce a phosphate concentrate with the required grade and recovery (38.6 per cent P2O5, 2.67 per cent Fe2O3, 13.7 for P2O5/(Fe2O3 + A1203), at P2O5 recovery of 81.5 per cent). The possibility of recovering the rare-earth phosphate, monazite, from the Mt Weld deposit by flotation was also studied.

Jan 1, 1991

By Real F, Carvalho P

During the development of the Neves-Corvo Underground Copper Mine, since 1981, inflow of water has been encountered in the mine workings, which consist of a ramp from surface 5 km long, a shaft 575 m deep and access crosscuts through the massive sulphide orebodies of Neves, Corvo and Graga, which are three of the four known deposits up today. Mine-hydrological studies have established the main characteristics of the hydrological system and its evolution in space and time. In a geological setting of low permeability rocks of Paleozoic age, tectonically affected by thrusts and faults, this has involved consideration of the relation with surface and ground water as a result of mine dewatering processes. The hydrological systems are described and summarized in this paper together with the techniques employed to study their origin and evolution, namely hydrochemistry, thermometry, piezometry and isotopic tracers.

Jan 1, 1988

By Howarth W. J, Sowerby B. D, Watt J. S

On-line analysis systems have found widespread application in the metalliferous mineral and coal industries. The continuous analysis and rapid response of these systems has led to improved control of mining, processing and blending operations, with increased recovery of valuable minerals and coal combustibles.The paper reviews developments in on-line analysis by CSIRO and Mineral Control Instrumentation Ltd which led to the award of the Australia Prize 1992. These commercialised systems analyse mineral and coal slurries; determine the ash and moisture contents of coal on conveyors, and the moisture content of coke on conveyors; and determine the carbon content of fly ash. These gauges are estimated to have resulted in productivity increases valued at $50 million per year to Australia.

Jan 1, 1993

By Ho D, Yang J

The ready availability of powerful desktop workstations, which combine 3D real-time graphics and processing speed better than that of supercomputers of a few years ago, now allows the cost-effective solution of real world geomechanics and underground mining strength simulations. The inclusion of geotechnical factors such as rock joints and porous flow on strength and stability are discussed together with the range of available deformation and failure models for soil, rock and concrete. This paper describes the capabilities provided by finite element graphics and analysis software for modelling and sequential investigation of both excavation and lining, or rock bolting, construction sequences. Examples of the use of finite element models in mining are also included in the paper, together with a discussion of the required people, software and computer hardware resources required to achieve timely and productive results.

Jan 1, 1995

By D Reid

Run-out analyses of tailings storage facilities are typically undertaken using methods based on rheological theory. These are reasonable techniques to model the behaviour of tailings that, through significant run-out and possibly mixing with supernatant water, are generally acting in a fluidised manner. Such modelling often follows on from two-dimensional continuum analysis models where, if failure is predicted, grid failure often occurs when deformations begin to increase. This results in a disconnect between the prediction of failure and the modelling of the potential extent of the failure.Recently, rezoning methods have been incorporated into commercially available two-dimensional soil mechanics deformation codes. Rezoning techniques enable large deformations to be modelled within a two-dimensional continuum analysis framework; however, while promising, the use of such tools is not yet widespread, and a consensus is yet to develop on how they should be applied to tailings dam run-out modelling.This paper uses FLAC rezoning techniques to model the flow behaviour of two historic tailings dam failures. The purpose of these analyses is to critically assess the performance of rezoning against some available historic failures. The required data to undertake such an analysis is outlined, along with the inherent limitations and assumptions required. Parametric analyses are outlined to address some of these issues. In general, the analyses undertaken underestimated the flow distance observed in the historic failures by varying degrees; however, in some instances, the analysis reasonably reproduced the qualitative shape of the initial failure zone. A variety of potential reasons for the discrepancy between historical observations and the models undertaken are provided.CITATION:Reid, D, 2015. The use of rezoning techniques to model historic tailings failures, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 201–206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015