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While the potential for the discovery of new high grade resources exists, it is almost inevitable that the ore resources used to provide society's ongoing demand for primary metals will deteriorate over time as the higher grade reserves are exploited first and are progressively depleted. This deterioration in quality of metallic ore resources will bring about significant interactions with other resources such as energy and water, resulting in an increase in the amount of these resources required per unit of primary metal production. In this paper it is shown that as ores deteriorate in quality, the contributions of the mining and mineral processing stages to the life cycle-based embodied energy and water of primary metal production will increase significantly. Therefore efforts to reduce the impact of deteriorating ore resources on energy and water consumption should focus on these stages.   The results from life cycle assessments of the production of various metals by a number of different processing routes, particularly copper and to a lesser extent nickel, have been used to identify a number of opportunities and technologies for reducing the energy consumption in the mining and mineral processing stages, including: comminution, eg high pressure grinding rolls, stirred mills, ore sorting, preconcentration, advanced blasting techniques, advances in diesel technology for loading and hauling, alternative processing routes, eg heap leaching, in situ leaching, water treatment and re-use, water quality 'fit for purpose', dry processing, floating modules to reduce evaporation, and paste thickeners. All the above and existing developed flotation technologies can impact on the mineralogy of the concentrate supplied to the smelter. Removal of gangue minerals early on in processing may have further downstream process implications on fuel and water requirements. The above technologies are in various stages of development, with some more advanced than others. However, all can be expected to play their part in improving the sustainability of the Australian mining industry.

Jun 1, 2010

This paper describes the technique developed by the Australian Coal Industry Research Laboratories (ACIRL) for the treatment of bore core samples to obtain data for coal preparation studies of the target reserves. The particle size distribution within the sample has a significant influence on the relationship between the yield and ash per cent of the floats coal at any ash level. The size analysis within the reconstituted feed from a coal preparation plant is determined by the size analysis of the feed coal, physical degradation of material in the process, and the breakdown of associated shales in water. The extent of material breakdown was studied in the ACIRL coal preparation pilot plants. The method of bore core evaluation includes simulation of this breakdown in a sample selectively crushed to conform with predicted or known run-of-mine size distribution. Modifications have also been made to the laboratory methods for froth flotation to approximate more closely with industrial practice.

Jan 1, 1977

By A Jafari, N Khalili, M Vahab, P Broumand

This paper presents the implementation of the eXtended Finite Element Method (XFEM) in the general-purpose commercial software package COMSOL Multiphysics for multi-field thermo-hydromechanical problems in discontinuous porous media. To this end, an exclusive enrichment strategy is proposed in compliance with the COMSOL modelling structure. COMSOL modules and physics interfaces are adopted to take account of the relevant physical processes involved in thermo-hydromechanical coupling analysis, namely: the mechanical deformation, fluid flow in porous media and heat transfer. The model preprocessing, level-set-updates, coupling of the relevant physics and postprocessing procedures are performed adopting a coherent utilisation of the COMSOL’s built-in features along with the COMSOL’s LiveLink for MATLAB functions. The capabilities and performance of the proposed approach are investigated by examining several multi-field thermo-hydro-mechanical simulations with reference to the block caving process in mines.

Nov 29, 2022

As a basis for my address to you tonight I thought it might be opportune if we considered the great history of the mineral industry in Australia, and the contribution it has made to the development of the country. While it is perhaps interesting to review the achievements of the past there is also the opportunity to examine the developments of the future.The names generally given to the three periods of man's life on the earth-the Stone, the Bronze, and the Iron Ageand to which should perhaps now be added the Atomic Age, imply the vast importance of the progressive steps in 'man's discovery of minerals and the means of working them. They tell the story of his advance from the flint knife to the bronze celt, and then to the keen-edged iron weapon, and now to the possibilities of the peaceful application of atomic energy. Not only have the stories of gold, iron, copper and tin told a great deal of the history of the progress of mankind, but they have also traced the commercial and industrial growth of Australia over the last century.Gold in the 1850's was responsible for the most significant period of immigration Australia has ever had-when the population almost tripled in the ten years to 1860. Minerals were also responsible for opening up Australia and determining the pattern of settlement. As mineral finds were made, railways were constructed to these fields, then agricultural development followed.Then, as the industrial era started, minerals provided the raw material for Australia's rapid industrial expansion, and they have all contributed to the extent that they have made...

Jan 1, 1960

By G C. Kiel, G J. Nicholson

Corporate governance has never been more topical. A glance at any major newspaper or business publication will reveal a litany of corporate failures based upon the governance of the organisations involved (eg Byrne, 2002; Hayes, 2002; The Economist, 2002). The increased compliance requirements and speculative nature of our industry means that corporate governance systems are, if anything, more important than in the general business community (Arthur, 2001). Rather than focus exclusively on the contribution of governance to corporate failure within the mining industry, however, our objective in this paper is to examine how boards can add value to the corporations that they govern. In order to highlight how a board can add value to a company, we commence by outlining the role of the board in the modern corporation in general and the mining industry in particular. We then introduce the concept of shareholder value and identify the steps on which a board needs to focus to enhance shareholder value through value tracking processes. Our discussion pays particular attention to the importance of organisational culture to the companyÆs activities and utilises three case studies from the mining industry. We conclude with an overview of what mining boards can do to enhance their culture and drive performance changes for the benefit of the companies they govern.

Jan 1, 2002

Gold bearing sediments at Scotland Point occur within the Quaternary Gibbston Fonnation, which underlies Cromwell Flat in Central Otago. Gibbston Fonnation unconformably overlies Teniary Manuherikia Group clays, sands and quartzose gravels. Gibbston Formation sediments are composed of a texturally diverse, multistoried lithostratigraphic succession of sandy/gravelly/bouldery lithofacies, deposited within a multiple channel (braided) depositional environment. Lithostatigraphic analysis indicate an upward overall decrease in average grain size, reflecting a concomitant reduction in stream competence. This trend results from progressive channel abandonment as major distributaries avulse across the outwash plain. Grade distribution of alluvial gold is controlled by aggradational and to a lesser extent degradational lithofacies deposited as distinctive braid bar forms near the base of the sequence. These lithofacies were deposited at different topographical levels on the outwash apron, under variable hydraulic conditions. Recognition of large-scale auriferous bedforms within the braid bar depositional system coupled with an understanding of lateral facies relationships, allows headgrade control on run of mine ore and quick determination of overburden to ore ratios.

Jan 1, 1988

By Bhattacharyya A. K

A strata parameter is introduced to include the deformation characteristics of the undermined strata in the prediction of subsidence movement. By using the strata parameter and mining factors as parameters, a nomogram for predicting the maximu

Jan 1, 1994

Anglo Platinum recognised with its expanded operations the need to change its evaluation strategy due to increased sample volumes and the pressure it created at laboratories. The sender/receiver analytical scenarios had to change in order to curb costs and to prevent substantial investments in new sampling and analytical facilities. Given the high cost associated with correct sampling systems and sampling protocols and the shortage of technical resources a strategy of single point sampling and analysis was introduced. The analysis was then done at an ISO17025 accredited laboratory with ten per cent checks, subjected to careful statistical scrutiny. Logistical problems increased with respect to weighbridge congestion, maintaining sampling quality, throughput of samples in the sample preparation areas, manual quality control systems in place, audit trails and analytical capacity throughout all operations. This required the expedited improvement of existing sampling practices and the development of new sampling methods and equipment. Anglo Platinum is classifying and standardising sampling equipment, sample preparation and analytical procedures for all process streams with the view to minimise overall uncertainties. Major investments were made into a customised LIMS and automated equipment for data management, reduction of manual transcription errors and streamlining of sample processing. Anglo Platinum is committed in rolling out the enhancements to all sites as priority dictates.

Jan 1, 2008

By Ho E

Analyses of several nickel mattes from around the world show a significant variation in their copper content. Typically, matte contains an alloy, heazlewoodite and a copper sulphide phase. The various commercial methods of processing these mattes are reviewed and some of the fundamental factors which determine the choice of leaching system are discussed. Electrochemical studies on pure heazlewoodite and millerite in sulphate and chloride media are compared which show that nickel sulphides react via a series of nickel deficient sulphides and exhibit passivation as nickel is removed. Differences in the electrochemical behaviour of nickel sulphides in chloride media are attributed to greater crystallinity of sulphur and less formation of'NiS2. The electrochemistry of mattes differs because of the presence of alloy and copper. Copper in the matte modifies the potential for alloy dissolution and the rate of anodic dissolution of nickel. At elevated temperatures, Cu(II) in solution exchanges with NiS and completes the leaching of nickel at relatively low potentials without significant oxidation of sulphur to sulphate. It is concluded that there are fundamental advantages to leaching nickel matte in chloride media using Cu(II)/Clz as the oxidant.

Jan 1, 1996

By Premur V

In industry and power production and distribution large quantities of fine wastes are produced. These are above all fly ash and phosphogypsum. Attempts are made to use them as secondary raw materials in industry and construction. Since they contain dangerous and harmful components or are nonhomogeneous their direct application is limited so that they are treated as waste. This paper reports on tests conducted with the aim of agglomerating the mentioned fine industrial wastes by pelletisation. The aim of this resarch was to obtain agglomerated product suitable for handling, transport and dumping. At the same time efforts were made to incapsulate harmful components by producing pellets with protective shells. Next, pellets without binders and with different binders were produced. Strength, resistance to freezing and solubility of pellets were tested. All the fine industrial wastes under survey were found to be suitable for pelletisation. The utilisation of appropriate binders ensures pellet strength required for safe handling and ecologically sound deposition of pelleted Material.

Jan 1, 1993

By P Gy

When it comes to sampling theory, a bad sampler is a bad sampler, no matter what, and a sampler is either bad or good. It also is of critical economic importance to tell and understand the difference, especially in a metallurgical plant. In this paper, the grand principles of Sampling Theory are first recalled, then the most popular types of sample cutters for plants are critically reviewed. It is concluded that the industry has a lot of progress to make in that direction, although improvements usually pay for themselves very quickly.

Jan 1, 2002

By L Yao, J Li, C Sammut, B Li

The underground mine environment is inherently complex and hazardous, which necessitates ensuring mining workers’ safety. With the fast development of AI techniques, human activity recognition has become a crucial task to enhance daily life, especially in such challenging settings. This enables automatic monitoring and detection of the mine workers’ activities and operations on a large scale, which leads to better support of workers’ safety and welfare. Existing traditional uni-modal approaches, which use data of one single modality, suffer from low data quality and noise, so they struggle to generalise effectively in such extreme conditions (Li et al, 2022). As underground mines have extreme and complicated environments, such as dust, low light, signal interference, and rugged terrain, uni-modal approaches could not resolve such obstacles and are not suitable for real-world deployment. Multi-modal human activity recognition approaches could use data from multi-modal sources, thus capturing complementary information and producing robust and effective performance in recognising and monitoring mining activities. In this case, designing suitable multi-sensor hardware and AI activity recognition models has become a pivotal task. Producing efficient multi-modal approaches for edge deployment is another problem worth exploring.

Sep 1, 2024

By Kramadibrata S

Over the years many attempts have been made to develop a means of assessing the excavatability of rock. Most of them are based on an empirical rating system while some authorities still propose the use of seismic velocity as a direct predictor of the rippability of a rock mass. On the other hand there are a number of classical models which have been developed to define the cutting force required at the pick or tooth of continuous miners.While these methods have been applied with various degrees of success to the design of excavation systems there is no generally acceptable method of defining the excavatability or cuttability of a rock mass in terms of the machine power required to generate a particular rate of production.The authors have attempted to overcome this deficiency by recording the intact and rock mass properties at a number of surface mines where continuous miners were in use and to use this data to examine the relationships between the relevant dimensionless groups developed from a dimensional analysis of the problem.The results obtained are encouraging and it appears that this new approach to the problem could lead to civil and mining engineers having a means of predicting the cutting power required to excavate rock at a given rate at any site.While this paper does not include a review of past work it refers to a number of key publications which will give the reader an excellent introduction to the subject.It is important to point out that the research work reported in this paper is part of a doctoral research project at Curtin University of Technology on the Influence of Intact Rock and Rock Mass Properties on the Design of Surface Mines. One of the major objectives of this project is to explore the possibility of developing a technique for predicting the excavatability of rock in surface mines at the design stage.This paper therefore commences with a brief reference to the continuous surface miners in use at the test sites followed by some original work by the authors in applying Dimensional Analysis to analyse the macro-performance of mechanical excavators. Following an analysis of the experimental data the authors validate the wider use of the model by referring to its successful application in predicting the power required to excavate rock by continuous surface miners at other sites.

Jan 1, 1995

By J Lyons, S Baker, D MacHunter, D Pepper

Mineral processing plants require a storage buffer to bridge differences in production rates between mining and processing. Where coarse ores are processed, such as coal or hard rock, this buffer may be an ore stockpile or silo. For wet-mining processes, eg dredging or hydraulic mining, or where fine ores are slurried close to the mining face, a surge-bin is used to contain the plant feed and smooth out the variations in mining rates. These bins have gradually evolved from simple storage vessels to units that are now frequently part of the mineral separation process itself, such as providing a desliming function to remove deleterious ultrafine gangue. This feed conditioning is often essential to achieve the levels of plant performance required in times of declining ore grades and or where inherent ore characteristics make separations harder to achieve. To achieve these dual roles requires careful consideration of bin design factors such as geometry and lining selection and increased use of instrumentation and advanced, or remotely supervised, control systems. All this ensures they provide capacity to smooth out variations in mining rates and guarantees that when conditioning ores or adjusting slurry densities ahead of the plant it is achieved without loss of valuable minerals. This paper examines the evolution of the modern surge-bin from a simple, so called, constant density tank with its inherent mass-flow compromises, limited feed preparation and beneficiation abilities, and footprint penalty, to a current state-of-the-art surge-bin, the LFCU, with a control system which provides demonstrable steady outputs, while conditioning and in some cases beneficiating the ROM material and all from a highly compact unit. It further discusses their use in other applications around the world, for example providing the necessary security for long distant high-density pumping systems; constant high density, low water usage, tailings disposal pipelines and high capacity ultrafine iron ore beneficiation.

Aug 24, 2022

By P Woodward, T Ly, N Muhamad

OZ Minerals' Prominent Hill copper-gold concentrator is located 650 km north-west of Adelaide in the Gawler Craton of South Australia. The concentrator was built in 2008 and commenced commercial production in early 2009. The Prominent Hill concentrator is comprised of a conventional grinding and flotation processing plant with a design capacity of 8 Mtpa. The flotation circuit includes six rougher cells, an IsaMill for regrinding the rougher concentrate and a Jameson cell preceding the three stage conventional cell cleaner circuit.Since its commissioning, the Prominent Hill flotation circuit has been the focus of a series of projects aimed at continual performance improvement. This has been achieved by a systematic approach of project identification, evaluation and implementation which has led to a progressive improvement in flotation performance. Innovations that have been successfully implemented include aspects of cell design and operation, and reagent suite optimisation.Improvements to the mechanical cells initially focused on the installation of a modified rotor-stator design in the rougher circuit, as recommended by Outotec. Isolated cells were fitted with this technology and proven to provide a benefit for copper recovery before the design was trialled in subsequent cells along the bank. Based on this success, further modifications were made to other aspects of the rougher and cleaner cells.Laboratory trials conducted at Prominent Hill involve a screening process identifying potential reagents from a list of products, which are then rigorously tested in the laboratory before one is selected for trial in the concentrator. Where these reagents have demonstrated a statistical improvement in performance they have typically been incorporated permanently into the flotation circuit. This paper discusses the process of continual improvement at the Prominent Hill flotation circuit and the optimisation achieved by the implementation of key initiatives.CITATION:Woodward, P, Muhamad, N and Ly, T, 2013. Optimisation of the Prominent Hill flotation circuit, in Proceedings MetPlant 2013 , pp 431-444 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By J Bryant

In recent years the mining industry has suffered from skill shortages in a range of disciplines including mine geology. As a consequence, many businesses operate with incompletely filled organisation charts and technical professionals are frequently thrust into roles earlier than previous generations of geologists, engineers and metallurgists. Exacerbating the difficulties managers face with recruiting suitably experienced professionals is the churn of people through roles. Churn may be caused by internal pressures related to the rapid increase in projects and opportunities within a company or by external factors including the high workforce mobility resulting from the advent of fly-in, fly-out (FIFO). Historically, new entrants into the mine geology profession often received on-the-job training from their more experienced colleagues. This training, supplemented with targeted skills and knowledge enhancement through dedicated short courses, ensured the wide range of skills, knowledge and abilities required in the complex role of mine geology were continually renewed. Faced with an influx of new graduates and a dearth of mine geology professionals in the critical ten to 15 year experience range, the industry needs to develop new paradigms to ensure that the full business benefit of the mine geology function is delivered. This is increasingly important as the complexity of business planning built on geologically-based variables grows. Mine geologists are now faced with the potential incorporation of geometallurgy and waste characterisation along with energy efficiency, carbon-economy and other environmental issues into their roles. Providing baseline data, models, operational control and reconciliation for a wider range of variables further stretches the already limited geological resources available to the industry and exposes personnel with relatively low levels of experience to potentially business transforming decision processes. This paper outlines a successful approach to mentoring at the individual and team level. It discusses what went well and what could have been done differently from both the mentor and menteeÆs perspective with examples from case studies and offers insights into a new approach to dealing with gaps in organisation charts and high turnover of personnel.

Jan 1, 2009

By L C. Thompson

BioLix is the term for a new class of biologically-derived lixiviants for precious metals (gold and silver) recovery. BioLix can be used as an alternative to cyanide on virgin and spent ores. The BioLix process is based on inducing microbial enzymatic reactions that generate organo-lixiviant chemicals. The bioprocess involves a two-stage culture strategy. First, specialty microorganisms are cultured to generate a high biomass. Then, a food-grade quality amendment is introduced that forces the microorganisms to produce the organo-lixiviant. The second-stage culture is applied to the ore where the microbial/lixiviant system acts on mineral surfaces to extract precious metals. The process operates at ambient temperatures and near neutral pH. This paper will examine the BioLix process through an extensive laboratory development and demonstration project. Laboratory development consisted of identifying and isolating specialty microorganisms and inducing agents for the production of the organo-lixiviant solutions. A demonstration was performed on low-grade and high-grade oxidised ore from the Buffalo Valley mine in Nevada, USA. Results indicate that the BioLix process was comparable to cyanide in terms of gold recovery and operated at near neutral pH and ambient temperatures. Applications for the BioLix process will be discussed including spent-ore re-leaching, cyanide replacement for virgin ore, and in situ mining.

Jan 1, 2004

By Smith T

Bacterial oxidation is often attributed with the advantage that a high level of gold recovery can be obtained at a relatively low level of sulphur oxidation. This is sometimes attributed to the bacteria "tunneling" towards gold inclusions, however it is often due to the presence of two or more sulphides of differing gold content which leach at different rates. Gold is liberated from the individual sul- phides linearly with oxidation. The distribution of gold between pyrite and arsenopyrite in two samples taken from a prospective gold resource was examined. The two samples showed differing responses to bacterial oxida tion and it was shown that this was due to differing intrinsic gold grades in the mineral phases and differing proportions of the minerals in the two samples.

Jan 1, 1991

By N Kusuma

Recoverable copper and gold estimates for resource models and ore control routing decisions at Batu Hijau were initially based on flotation testwork from several commercial laboratories. Due to the greater number of copper and gold assay grade available, regression relationships were developed between assay grades and flotation recoveries. Other recovery controlling variables such as oxidation and lithology were included to improve the regression models. With additional drilling, more flotation work was carried out and the regression models were revised to include the new flotation data, also alteration classification and in situ pH. The regression models were replaced in favour of spatially derived models for ore control and short range mine planning. To harness local variability in the block model, blast hole flotation testing is carried out in unison with routine grade assaying. Recovery data are processed (kriged) simultaneously with grade assay data prior to ore polygon delineation. Short range mine planning utilises this model in conjunction with a spatial recovery model derived from drill core flotation data. Long range mine planning utilises the æhybridÆ recovery model whereby the globally robust regression recovery models are overprinted by a spatial (kriged) recovery estimate where flotation data density is adequate (Phase II reserve).

Jan 1, 2002

By R Fleming, G Jones

An ocean outfall is currently under construction in Christchurch, New Zealand to transfer treated wastewater from the existing treatment ponds at the city wastewater treatment plant to diffusers located 3 km offshore. The New Zealand $85 million project comprises a new pump station and 5 km of 1800 mm diameter pipeline with a design capacity of 6.0 cumecs. The pipeline comprises 2.3 km of concrete pipe installed by microtunnelling and 2.7 km of polyethene marine pipe installed by dredge and lay. This paper describes the consent process, key environmental and community constraints, the tender process, risk provisions included in the contract, the type of contract, partnering provisions, geotechnical design issues and the pipejacking construction activities and issues.

Jan 1, 2008