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By Purvis A. H, Greenwood-Smith R, Sowerby B. D

A nuclear technique for the determination of copper and nickel in bulk samples and drill core has been developed at Lucas Heights andfield-tested at Mount Isa. The technique, which is highly specific to the element being measured, utilises the gamma-ray resonance scallering process.A bulk mineral analyser was installed in mid-1976 for the routine assay of copper in bulk samples and drill cores, and remained in operation until late 1981. The operation of the analyser over this five-year period is reviewed with particular emphasis on reliability, accuracy and principal usage.The main application of this analyser was in stope planning and design whereby several thousand drill-core and Wall-chip samples were analysed. It was also used as an aid to underground grade control of stopes where ore dilution by supporting barren backfill was a problem.

Jan 1, 1984

Iron ore in the Pilbara Region of Western Australia varies in composition giving iron ore a range of densities. An accurate density figure of the material leads to accurate calculations of production throughput. Density studies of two separate iron ore mines were conducted in the Pilbara. Procedures and results are reported here.The Pilbara Region of Western Australia has a number of iron ore operations. Two mines have conducted density studies of their materials. The purpose for the studies was to determine an accurate in situ bulk density that could be applied to volume and tonnage calculations of the operation. It was identified that density was one culprit causing calculation variations. Density is an important figure used to estimate ore reserves, equipment requirements, production rates and indirectly costs and sales revenue. One study was conducted at Rio TintoÆs Robe River Mine based near the town of Pannawonica. Its Mesa J orebody is currently being mined and is a low-grade deposit of goethite and hematite (Burnham, 2003). A separate study was conducted at BHP BillitonÆs Yarrie Mine situated north of Newman and east of Pardoo. Its orebody consists of high grade formed by a supergene enrichment of cherty material and a burial metamorphism to produce hematite (Richardson, 2002). The method used to determine density was by large-scale samples using the pre-mining in situ volume of the material and the weight in tonnes after mining.

Jan 1, 2003

By Aspinall T. O, Loch R. J, Bell L. C

Design of reshaped spoil surfaces is an important pan of rehabilitation of spoil piles resulting from open-cut coal mining. To achieve the optimum design, it is necessary to make accurate predictions of soil losses from spoil piles. Predictions can be based on data gathered using laboratory and field rainfall simulators and field plots. These data are used to derive input parameters for erosion prediction models. Model input parameters include rainfall erosivity, spoil erodibility, sediment size distribution, runoff, soil loss and peak runoff rate. Model outputs can be used in design and include predicted sediment size distribution and predicted soil loss.The traditional method of gathering input data is monitoring field plots. This method is very expensive, must be done on a long-term basis and is affected by irregular rainfall. Long-term field plots are necessary to obtain data that can be applied to empirical prediction models such as the Universal Soil Loss Equation (USLE).

Jan 1, 1992

New Caledonia is a major metallogenic unit of the south-western Pacific Rim. Its mineral production is of world significance and it has an unusually well diversified mining history. New Caledonia's main metallogenetic potential is, however, associated with its unique ophiolitic complex and its important mineral- izations of nickel, chrome, cobalt and iron. Gold has been found in all the four basic tectonic elements of New Caledonia: the Central Massif, the West Coast basalts, the ophiolitic complex and the Caledonian North. Some analogies are attempted. Only the Caledonian North has supported mining operations (213 kg Au). More recently tenuous gold indications have been found within the ophiolitic complex, possibly associated with Oligocene plutonism.

Jan 1, 1987

By M Clay, J Dunlop

Thermal and metallurgical coal mining in Queensland has resulted in mines which contain voids due to open cut mining. While there are several proposals for greenfield coalmines or expansions to existing operations, many existing open cut coalmines are reaching maturity and most will leave one or more residual voids in place. The rehabilitation of mine voids is challenging. Water held in voids will evaporate over time leaving solutes to concentrate. This is likely to lead to poor water quality with limited practical use. The most basic practices to rehabilitate voids have historically involved stabilising the high and low walls, bunding to provide flood protection, and preventing public access. Regulatory reforms for mine rehabilitation were introduced in Queensland as part of the Mineral and Energy Resources (Financial Provisioning) Act 2018, and aimed to strengthen progressive rehabilitation planning, limit risks to the environment and improve outcomes for local and regional communities. Under the reforms, the goal for rehabilitation of voids is to achieve a safe, stable, and non-polluting landform, which can sustain a post-mining land use (PMLU). The reforms also introduced a requirement to describe rehabilitation of mined land in Progressive Rehabilitation and Closure (PRC) plans, replacing the description of such plans in Environmental Authorities (EAs). The reforms are not retrospective and recognise historic approvals for voids, meaning established voids will remain in the landscape as non-use management areas (NUMAs). The objectives of this study were to outline historic void rehabilitation planning practices, describe water quality limitations of Queensland mine voids and identify possible opportunities for improved planning

Aug 2, 2023

By A Nugraha, H Thanasekaran, K Tatetdagat

The Kanowna Belle gold mine is located in the Eastern Goldfields of Western Australia, approximately 18 km north-east of Kalgoorlie. The processing plant is designed to process 2 Mt/y and has the capability to treat both refractory and free milling ore from the Kanowna Belle and Kundana mining operations.The Kanowna Belle ore is refractory with the gold mineralisation occurring mostly as fine-grained inclusions in pyrite or as very fine-grained gold located in pyritic arsenic rich growth zones. The Kanowna Belle refractory process includes flotation, roasting of the flotation concentrate, and calcine leaching to extract the gold from the ore.Mineralogical analysis of feed and tailings streams from the flotation circuit have shown that the gold bearing minerals are well liberated and confirmed they are mainly associated with pyrite. Nearly 40% of the flotation circuit losses are in the -38 µm size fraction. To improve the flotation circuit recovery, the fine particle gold recovery was targeted. A Cavitation Tube column was selected for the site-based pilot test work program. This paper presents data generated from the on-site test work, and the benefits of the Cavitation Tube column to improve fine particle flotation.CITATION:Nugraha, A, Tatetdagat, K and Thanasekaran, H, 2018. Flotation circuit efficiency improvement at Northern Star Resources Limited’s Kanowna Belle gold mine, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 403–412 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By J Stipcevich, N Patel, J Faithful5, S Narendranathan, L Tatnell4

ENGIE, the current owner and operator of the Hazelwood Open Cut coalmine, are in the process of rehabilitating the mine site in preparation for mine closure. Bucket wheel excavators (dredgers) used during coal mining operations are in the process of being demolished, which involves the controlled felling of dredger components using explosives. With the mine located in close proximity to the Morwell township and other critical public infrastructure, it is crucial that the use of explosives and the possible implications for mine stability is well understood. The felling of Large Mining Equipment (LME) will apply an impact load immediately to the underlying coal benches with the adjacent coal batters potentially at risk also of adverse slope stability impacts. This paper presents the 3D stability modelling methods employed to successfully assess the potentially adverse stability implications associated with LME collapse.

Jun 21, 2022

By Shibata Y, Shimizu R, Fukushima A

Kobe is divided by the Rokko Mountains, runn- ing from east to west. The southern section of Kobe is highly developed in contrast with the northern section, but big, new residential pro- jects like the Hokusetsu New Town and Hokushin New Town are steadily being developed. To handle future traffic between the two sections of the city, the double-tracked Hokushin Line, now under construction, will connect the Shin Kobe Station of the Kobe Municipal Transit (Kobe's subway system) to the Tanigami Station of the Kobe Electric Railway. The locations of Kobe city and Hokushin Line are shown in Fig.-1 and Fig.-2 respectively.

Jan 1, 1987

A calibration of the Frantz isodynamic magnetic separator relates the current in the electromagnet and the transverse slope of the chute to the specific susceptibility at which separation is being effected. In addition to providing a rapid measure of the specific susceptibility of minerals and composite grains, the calibration provides a guide to operation of the Frantz isodynamic separator for mineral separation, and to the nature of composite grains. The most sensitive magnetic separation is obtained by using the highest practicable current and transverse slope, and the lowest practicable longitudinal slope.INTRODUCTIONProbably all minerals have a magnetic susceptibility measurable by sensitive techniques. However, magnetic separation between minerals which have low but different specific susceptibilities, and which for many purposes are considered essentially non-magnetic, has only become practicable with the development of the Frantz isodynamic separator.The construction and principle of this highly sensitive separator has been described by S. G. Frantz as an appendix to a description by 'Gaudin and Spedden (1943) of its application to the separation of sulphides constituting mill products.Various publications (e.g. Hess, 1949, Hutton, 1952) refer to its use in separating the mineral constituents of rocks, ores, and unconsolidated sands.As used in this study the Frantz isodynamic separator consists of a vibrating chute mounted centrally between the pole pieces of an electromagnet (Fig. 1). This unit may be inclined in any direction by the universal mounting, and the electromagnet current is continuously adjustable from 0 to 1·5 amperes.

Jan 1, 1957

By G W. Wilson, P Ritchie, N A. Currey

The design and rehabilitation of potentially acid forming (PAF) waste rock dumps is site specific, being a function, among other factors, of the rock types, the dumping and storage method employed, and the climatic setting. The æstore and releaseÆ cover system developed to manage acid rock drainage (ARD) from mineralised waste rock dumps at Kidston Gold MinesÆ open pit operations in the semi-arid climate of North Queensland, Australia, has been monitored for seven years. The paper describes the philosophy behind the design of the PAF dump and æstore and releaseÆ cover system and the adaptation of the cover system over time to suit KidstonÆs conditions. The results of monitoring over the seven years since the first cover was constructed are presented, and the approach being taken at Kidston to ensure that the risk of impacts from any residual ARD is accommodated and to facilitate lease surrender are described. The Kidston story is a valuable case study of a successful approach to remediating an identified source of ARD in a semi-arid climate, which has actively engaged all Stakeholders.

Jan 1, 2003

By M Spleit

A long-term production schedule for the LabMag iron ore deposit in northern Quebec, Canada is derived using stochastic integer programming. The optimisation formulation maximises the schedule’s net present value while simultaneously managing the risk of deviations in production tonnages and qualities by considering stochastic simulations of the orebody instead of a single deterministic model. The formulation also smooths and minimises haul truck requirements and ensures that as mining progresses, space is created within the mined out pit for the return of waste material.CITATION:Spleit, M, 2014. Production schedule optimisation – meeting targets by hedging against geological risk while addressing environmental and equipment concerns, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 397–404 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

During the past seven years silver recovery has been increased from 9 per cent to over 61 per cent. The changes in plant practiee which have led to this increase are described. Gold room clean-up procedure has been varied, so that half the additional silver is obtained as pure silver chloride, which.is converted to silver bullion for marketing.

Jan 1, 1964

By Sheer T. J, Van Rensburg J P

The primary objective of this research was to address the demands imposed on self- contained self-rescuer (SCSR) performance dur- ing simulated escapes. The results clearly indicate that SCSR performance, apart from the inherent technological features, is a function primarily of the physical and anthro- pometric features of the wearer, and of the particular nature of the escape route. These factors consequently play a major role in the planning of any escape strategy, which may vary from mine to mine. It is therefore concluded that each mine would have to formulate its own escape strategy which in turn would depend on the choice of SCSR, and the particular escape Route.

Jan 1, 1988

By Taylor R. K A, Berglin C. I K

The manganese ore deposits at Groote Eylandt are quite variable both in regard to grade and physical cond- ition. In order to treat a wider range of these ores and to increase production a new primary-crusher and' concentrator complex costing $8 million has been installed and commissioned to treat ore at the rate of 12,000 tonnes per day. The initial testwork carried out to determine the method of the ore treatment required, and on which the design of the concentrator was based, is detailed. The flowsheet and equipment used is discussed together with the operation of the plant. The production achieved and product qualities obtained are given.

Jan 1, 1973

By Fletcher G

This paper will outline the design process, and the constmction and rehabilitation techniques proposed for the external waste dumps associated with the mining of the Wolfang Basin coal measures.The basin is located to the north of Clermont and immediately west of the Bowen Basin in Central Queensland, Australia. Development of the Clermont Coal Mine is planned for the mid-1990s after adequate sales commitments are obtained to allow the project to proceed.

Jan 1, 1992

By K Verbeken, D Seveno, A Maslov, I Bellemans

Recycling and decarbonisation current metallurgical processes is key for our planet’s future and in both cases, digital twinning will play an important role. However, the various modelling techniques being used for digital twinning require a lot of input values on variables such as viscosities, diffusion coefficients and surface energies that need to be known as a function of temperature, atmosphere and composition, but which are not widely available, such as in databases, for molten slag phases. The need for more accurate data on physical slag properties is clear and will be extremely relevant for making more realistic and quantitative simulations. Some of these properties are difficult to determine, which is inherent to the very high pyrometallurgical temperatures. Therefore, this work focuses on some aspects related to determining electrical conductivities, viscosities and surface tensions of slags via a combined experimental-modelling method. Besides experimental work, molecular dynamics (MD) simulations can be used to investigate oxidic slag physical properties. With MD simulations, one can follow the time evolution of a system (consisting of atoms or molecules) by integrating Newton’s equation of motion. The input for an MD simulation mainly consists of a force field as well as initial positions, velocities and mass of each atom. The determination of the transport properties in existing literature of MD simulations in oxidic systems, is typically based on incorrect assumptions. For example, to determine the ionic conductivity, the frequently-used Einstein-Stokes equation fails to take into account all ionic types and neglects correlated motion. Furthermore, the viscosity determination via the Einstein-Stokes formula also assumes independent motion of the different ions. This paper gives a brief overview of the opportunities and challenges related to the use of MD simulations for oxidic slag systems.

Jun 19, 2024

Since its beginning, with the works of D. Krige and later, G. Matheron, geostatistics has been analyzing in detail the essential factors at play in ore reserves estimation problems, with the ever-present aim of an optimal use of the available information. Not only do the reserves depend on the geological in situ resources, they also require a correct appraisal of many technical and economical parameters. The objective of the present paper is to show how the method of technical parameterization of reserves, which is at the heart of the geostatistical approach, provides an extremely powerful and versatile tool for characterizing a mining project. After a review of the main properties of the technique, its use in the economic optimization of a project will be examined. Two examples from copper and gold deposits will be given.

Jan 1, 1987

By Hunter GW

This paper gives an account of the filling system at Mount Isa from surface fill production to stope discharge underground. A brief explanation of the surface facility and reticulation is given prior to the discussion on aspects of underground reticulation. These include fill hole types, pipe and breastplate installation, wear characteristics, etc. The different types of fill and their respective applications is mentioned as a prelude to a general overview of the mining considerations associated with fill placement and its role in the long term planning strategy at Isa Mine. Some practical aspects of stope preparation and filling procedures are outlined for the various stoping methods. Finally a brief outline of future fill developments is given.

Jan 1, 1982

By I Onederra

A better understanding of the detonation performance of an explosive charge can be gained by directly measuring pressure, temperature and velocity of detonation (VOD). This is particularly important with explosives used in the mining industry because their performance is directly influenced by the degree of confinement given by the borehole diameter and the surrounding rock mass. A project funded by the Australian Coal Association Research Program (ACARP) was initiated in early 2009 with the view to design and build cost-effective prototype instrumentation to measure the relative differences in detonation pressures and temperatures of commercial mining explosives. The project’s primary focus was on low-density explosives. Low-density (also referred to as low shock) explosives have been available in various forms for nearly 20 years. There have been significant advances in the availability, reliability and flexibility of these explosives, which now offer a range of densities and degrees of water resistance. Their detonation performance is not well understood and cannot be accurately predicted with current ideal and non-ideal detonation codes. It was therefore viewed as important to be able to directly measure pressure and temperature during the detonation process of these complex mixtures in production blastholes. Identifying the pressure release patterns of both conventional and low-density explosives under different geotechnical conditions should provide the necessary information to both validate detonation codes and better define input parameters for breakage and fragmentation models. This paper gives a general description of the prototype instrumentation developed and reports on the results obtained to date in full-scale conditions.

Nov 8, 2011

By Clift N

Lead concentrate from the Isa and Hilton lead-zinc concentrators of Mount lsa Mines Limited is smelted at Mount Isa to produce a lead-silver bullion. This bullion is cast into four tonne blocks and shipped to Britannia Refined Metals Co Ltd, NorthDeet, England and to plants in Asia for refining and marketing. The traditional treatment stages at Mount lsa are sintering, smelting, and drossing and casting, with some of the sinter plant feed being pre-treated through an Isasmelt plant.A commercial scale lsasmelt based lead smelter was commissioned in early 1991.

Jan 1, 1993