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This paper will examine some of the significant developments in the training field in Australia in the past decade and the application of these changes to the mining industry generally, and the coal sector specifically. Three major aspects will be examined:1. Competency - the use of Industry Competency Standards and how these can be used for achieving enterprise performance requirements2. Assessment - making judgements about an individual's competence, and using a rigorous assessment system as the basis for the "authorisation" system at a mine3. Evaluation - ways to evaluate the return on investment in training, and convincing CEO's/shareholders that your training dollar is being spent wisely.Before examining these issues, it is important to understand the drivers of change in the training systems in Australia, and the functions that Industry Training Advisory Bodies (ITABs) perform.

Jan 1, 1998

By H Aoki, A Nakayama, K Morita, S Yamada

The thermal conductivity of mold flux is crucial for optimising the productivity and quality of steels. This study investigates the thermal conductivity of molten oxides, including CaO-BO1.5-AlO1.5 (CBA), CaO-BO1.5-AlO1.5-SiO2 (CBAS), and CaO-MgO-BO1.5-AlO1.5 (CMBA) melts, using a hot wire method. Additionally, their structure is examined using Raman spectrometry and magic angle spinning nuclear magnetic resonance (MAS-NMR) to explore their relationship. Furthermore, first-principles calculations are employed to assess the covalency of each bond in the melts for a more quantitative analysis of their relationship. The study confirms that an increase in the CaO concentration of the CaO-BO1.5-AlO1.5 melts reduces the amount of bridging oxygen and consequently decreases thermal conductivity. The covalency of the B[4]-O bond is highest, especially when the second-nearestneighbour Al atoms transition from Al[6] to Al[4], forming the AlB3O7 structure with B[4]. The relationship between thermal conductivity and the structure of CaO-BO1.5-AlO1.5-SiO2 melts can be quantitatively assessed using the degree of polymerisation of the network structure and the variation of covalency as indicators. Furthermore, replacing CaO with MgO in the CaO-MgO-BO1.5-AlO1.5 melts reveals a mixed alkaline earth effect on thermal conductivity.

Aug 21, 2024

By S Cossfo Torres

Minera PenmontÆs gold mine, La Herradura, is located at the northwestern Mexican state of Sonora and consists of an open pit mine and heap leaching facility for the recovery of gold. The production began in July 1998, and today La Herradura produces about 200 000 oz of gold per year. Standard sampling and assaying protocols were established during exploration based on heterogeneity tests. However, at deeper zones of the pit, coarse gold became evident and it was necessary to develop a new sampling protocol in order to minimise the fundamental error and improve the metallurgical accounting. This new sampling protocol requires cyanide leaching the whole pulverised sample from the blasthole, assaying pregnant solution and fire assaying 50 g of tailings. A sampling study was performed on 195 blasthole samples analysing gold under the standard and new protocols. The new protocol demonstrated that the original one underestimated gold grade by approximately 27 per cent, with impacts on ore misclassification and metallurgical accounting. According to the ore grade control system, mineral with gold grade above 0.35 g/t was sent to the leach pad and mineral with lower grade was classified as waste. Based on the sampling study, it was decided to classify a low-grade ore with gold assay between 0.20 and 0.35 g/t which was stored for future treatment under better gold prices or should mine production decrease. These two conditions were present during 2005 and 2006, when about 3.5 Mt of low-grade ore were leached.

Jan 1, 2008

Alaska Native corporations, as representatives of the aboriginal inhabitants of Alaska, control the mineral rights to 18 million hectares of Alaska, approximately 12% of the state. These corporations were established through legislation passed by the United States Congress in 1971 designed to settle the land claims of the Native peoples of Alaska. Twelve corporations, each representative of a specific geographic and cultural region, were established and granted the mineral rights to most Native lands in their respective regions. Since that time the Native corporations have taken an active role in mineral development in the state. Generally through agreements with established mining companies, Native corporations encourage balanced exploration and development of their lands. Substantial mineral potential has been recognized on Native corporation land, which includes holdings in many historic mining districts of Alaska. Several world class deposits have been discovered on Native corporation land, including the Red Dog zinc-lead deposit, which began production in late 1989. The experience of Alaska Native corporations demonstrates that aboriginal peoples can be very positive forces in resource development.Alaska, although remotely located in the Northeast corner of the Pacific Basin, is playing an increasing role as a supplier of natural resources to the region and the world. Most of Alaska's privately held natural resources are owned by the aboriginal inhabitants of the state. These aboriginal inhabitants, now collectively referred to as Alaska Natives, have emerged in the last two decades as having a major international impact in mineral resource exploration, development, and production.

Jan 1, 1990

THE manufacture of Portland cement on a commercial basis dates back to the year 1824, when Joseph Aspidin, of Leeds, patented his process. It was, however, only within the past 25 years that the cement of to-day commenced its history, and during that period manufacturers have constantly tried to improve the grade of cement.The introduction of the rotary kiln at the opening of this century was the starting point of rapid development in the process of manufacture, and in the quality of the cement produced.Following on the rotary innovation came the wet process. This at first was used only where the raw materials were of a soft nature; but to-day nearly all classes of materials can be treated by this method. Oompared with the dry process, it allows for greater refinement of raw materials, more intimate mixing, better chemical combination, and economy in fuel. Taking advantage of this, the manufacturers in England and America are in a number of cases substituting the wet for the dry process.Subsidiary machinery throughout the factories, such as crushing and grinding mills, have also been vastly improved. The chemists, too, have done their share in the work. Long and careful research has proved the necessity for accurate proportioning of raw materials, thorough mixing, and very careful burning. All these factors combined have given us the product of to-day, which is consistent within very narrow limits, and far superior to that of the beginning of this cement era.

Jan 1, 1926

The resistance of lead to chemical attack and the ease of its fabrication has made it one of the most useful of the metals available to the chemical engineer and the electrometallurgist. It has proved to be of particular value in the manufacture of sulphuric acid, and since the conversion of the sulphur of pyritic ores into sulphuric acid is becoming the duty of the metallurgist, the corrosion resistance of this metal will be a matter of considerable interest to him from the standpoints of both producer and user. He realises that there is little to be gained in carrying the process of purification past the ordinary economic limit if little or nothing is to be added to its corrosion resistance, and he as user would not be willing to pay a premium for such purification if it can be shown that its reputed value has no scientific foundation.The metallurgist is well acquainted with the trouble and expense of meeting demands which have nothing torecommend them but prejudice and fancy. The valuable anti-corrosive properties of lead are very commonly ascribed to its forming insoluble compounds with the acids sulphuric, hydrochloric, carbonic, etc. If we trusted superficial visual evidence alone, such a view would receive strong support, but in the light of what we know of the mechanism of corrosion we must attribute its resistance to other factors much less obvious to casual inspection. Certainly there may be some mechanical obstruction set up to diffusion of the liquids towards the surface of the metal.

Jan 1, 1932

By U Berg, T Neumann, Y Song

Eutrophication of water bodies is one of the most severe environmental problems worldwide. It is well known that the availability of phosphate, as the limiting nutrient, is crucial for increased primary production and eutrophication. Calcite exhibits positive surface charge in most natural waters and can therefore be used for phosphate immobilisation. In this study, sorption experiments were performed in order to test different calcite materials regarding their suitability for use in restoration of eutrophic lakes. These short-term experiments were performed under different hydrochemical conditions (pH, SICC, initial dissolved P concentration) and with varying calcite properties (specific surface area and amount) in order to predict the long-term stability of the Ca-P-bonds. Peculiar shapes of isotherms that could not be explained only by adsorption processes were detected in the individual experiments. Depending on the residual P-concentration in solution, the isotherms can be divided into three sections indicating different processes responsible for the P-fixation on calcite surfaces. Adsorption prevails in equilibrium with lowest residual P-concentrations. The inflection of the isotherm at moderate residual P-concentrations suggests that precipitation and transformation of a Ca-P compound becomes dominant. This is supported by characteristic Ca/P-ratios for different Ca-P-compounds (b-tri- calcium-phosphate, octa-calcium-phosphate). On the new surface, phosphate ions again are fixed by adsorption. The observed transformation of P-bonding is crucial for sustainable phosphate immobilisation on calcite surfaces. While pure adsorption processes are reversible, the development of a thermodynamically stable Ca-P-phase, like hydroxylapatite, will lead to a lasting immobilisation of phosphate.

Jan 1, 2008

This paper presents the descriptions of a final year geological engineering project at the Royal Melbourne Institute of Technology involving the correlation of borehole and mapped ground conditions and their statistical Analysis.

Jan 1, 1994

In the last few years it has become legal for women to work without restriction underground in some States in Australia. Since the mid 1970's there have been women graduates in mining engineering from several Australian tertiary institutions. Women from this group are the first females to have been employed to do manual work underground this century. The questions which arise are "What are the current parameters surrounding the employment of women underground?" and "What have been the experiences of those women who have worked underground?". In order to answer these questions, contact has been made with the various mining schools in Australia, the relevant government departments, the main underground mining companies, the relevant unions and professional associations, and other women who have worked undergrond. Personal experience as both a miner and a mining engineer at the CSA Mine near Cobar in New South Wales is also used.

Jan 1, 1988

By R M. Papini, A C. Araujo, A E. C Per

Flotation is an important process used in the concentration of iron ores. One of the challenges for process engineers is the low metallurgical recovery associated mainly with the fines fraction. In this work, the use of synthetic flocculants in iron ore reverse cationic flotation was investigated. The flocculants utilised were polyacrylamides of high molecular weight and different ionic degrees. Bench scale flotation tests were performed to compare the flotation performance with and without addition of polyacrylamides. It was observed that cationic and non-ionic polyacrylamides cause a significant increase in the metallurgical recovery. The anionic flocculant did not improve the flotation performance. An adverse effect was a slight increase in the silica content of the concentrate. Flotation with polyacrylamides was influenced by the hydrodynamic conditions of the pulp, such as agitation and the weight percentage of solids in the flocculant conditioning and flotation stages.

Jan 1, 2005

By Ranford LC

Modern, research-based approaches to mineral exploration are essential to the future maintenance of the mineral industry. These need to fully utilise the rapidly expanding growth of understanding of the evolution of the earth's crust, and be properly integrated with advances in understanding of chemical and physical processes involved in ore formation. BMR has a major role to play in supporting the growth and utilisation of this research base, as well as maintaining the national geological and geophysical bases which are essential both to tactical and strategic interests of Australia and of its mineral industry. The objective development of data-process modelling is one target of such strategic research based on a more integrated approach to research by BMR, mineral companies, CSIRO and the universities with emphasis given to promoting positive feedback during research activities. Examples of the success of strategic research in Australia and overseas are noted in the Text.

Jan 1, 1986

Mineral exploration management has undergone major changes particularly in the last decade. Parallel to these changes in management, and partially responsible for them, have been the changes in governmental laws and regulations at both National and State levels reinforced by a highly competitive climate created by the exploration boom in Australia. The influence of overseas methods and approaches have been married to the Australian techniques resulting in a management climate which is not only familiar with the technical aspects of exploration, but is also familiar with the personnel, economic and legal phases associated with the expenditure of very large sums of money. The utilization of all the geosciences coupled with mathematical models and computer techniques for pre-selection and assessment of areas are now normal aids used in management decisions. Management techniques developed and being developed will ensure that successful exploration will be carried out if sufficient incentives are guaranteed.

Jan 1, 1974

Mining companies in Australia have grown in size and complexity over the past 20 years. The same period has seen exten- sive changes in the operating environment, with greater competition and intensified in- dustrial and social pressures placing new demands 'on mining activity. The new condi- tions require a management approach that emphasises strategic planning rather than operational efficiency. Strategic management evolves through four distinct phases, namely, financial planning, forecast-based planning, externally oriented planning and 'true' stra- tegic management. The most difficult transi- tion to make is from Phase 2 (forecast-based planning) to Phase 3 (externally oriented plan- ning) since management is often too involved in operations to find time to develop and main- tain a strategic orientation towards the mar- ket and competitors. Reorganisation of re- sponsibility for operations and improved op- erational processes enable management to concentrate on external opportunities.

Jan 1, 1980

The processes most likely to be adopted for beneficiating ores or concentrator streams containing a large proportion of particles finer than 10 um are froth flotation, selective flocculation, wet magnetic separation and selective leaching. Flotation will be made more efficient for very fine particles if ways can be found to selectively flocculate the valuable mineral beforehand (floc-flotation), to produce smaller bubbles and to reduce entrainment of ultrafine gangue. Schemes for selective flocculation have proved difficult to implement because of the delicate balance between surface forces (electrostatic, dispersion, hydrophobic) and hydrodynamic forces, that determines flocculation, and the changes which occur to particle surfaces through hydrolysis, oxidation-reduction and cross-contamination between minerals in aqueous suspensions. The search for a better understanding of selective adsorption of flotation collectors and flocculants continues and will be particularly important for the practical success of selective flocculation and selective magnetic coating.

Jan 1, 1986

By Ruffles B. R

A computer simulation has been developed to model the flow of copper ore in Isa Mine. It simulates extraction of copper ore from the 1100 orebody by load-haul-dump (LHD) units to ore passes, haulage from chutes on 19 level by Rockflo trains to crusher bins, crushing and hoisting. It can assess in terms of the tonnage and head grade of ore hoisted, the effect of varying operating strategies, as well as measur- ing shortfalls in required capacities of any of the operations (extraction, hauling, crushing and hoisting). The simulation was designed as a modular, deterministic, steady-state model with parameter input allowing complete flexibility in its use. Queuing theory is used extensively to evaluate the effect of interference at potential bottlenecks. The model has been used to determine the effect on production of varying train sizes, maintenance policies on the haulage circuit, orepass capacities, and extraction operations.

Jan 1, 1974

An on-stream iron ore analyser has been developed in collaboration with Hamersley Iron Pty. Limited for determining the iron content of both lump (- 30 + 6 mm particle size) and fines (- 6 mm particle size) on conveyor belts. The analyser, which is called IRONSCAN, is based on pair production, and is now commercially available from Mineral Con- trol Instrumentation Limited (MCI) in Adelaide. It can be mounted under existing conveyor belts with minimal modifications to the conveyor struc- ture, and the presence of steel cables in the belt does not interfere once the analyser has been correctly calibrated. The analyser has been exten- sively tested on both lump and fines on the shiploading conveyor at Damp- ier, and typically the root mean square (r.m.s.) deviation between single IRONSCAN measurements and conventional chemical analyses is better than 0.5% Fe. It is currently being evaluated on - 150 mm ore from the primary crusher at Mount Tom Price, and initial results are encourag- ing. The principal advantage of IRONSCAN is that it provides rapid infor- mation on ore grades. But perhaps its greatest potential is at the primary crusher where conventional sampling and analysis is very expensive to Implement. at the University of Melbourne, and those of us who were his students had learnt of the application of physical chemistry to pyrometallurgical processing, pioneered by Chipman in the USA, Wagner in Germany, and Richardson in the UK. It was possible, by applying this theoretical insight to the equilibria between metal, speiss or Legierung, matte and slag phases, to find a practical and effective way to recover metal values in some residues which had been accumulating for many years at the NA, but which had defied all attempts to treat them to that date. There was also an opportunity to study the batch lead refining methods still in use at all lead refineries apart from Port Pirie, and to devise optimis- ing techniques which greatly improved the operations and effected considerable savings. Next the writer spent some six years alternating between the BHAS, Port Pirie, and Imperial Smelting at Avonmouth in the UK, concerned with lead or lead-zinc smelting, and the develop- ment of several further continuous lead refining processes, before returning to Australia as Section Leader, Process Development in the CSIRO Division of Chemical Engineering, Fisherman's Bend, Victoria. Metallurgical opportunities which arose during this last period included the problem of tin smelting which had developed over about a decade: the world's tin smelters had been accustomed to treating fairly high grade tin concentrates, con- sisting of almost pure cassiterite, with very little impurity-mostly quartz, limestone, iron oxides, and sundry other silicates. Most such concentrates had been produced from alluvial deposits, where nature had already done some of difficult part of the mineral processor's work-at who knows what recovery-so that he could now produce high grade concentrates at high recovery. The smelters were not really set up for the treatment of lower grade concentrates, such as could be made with reasonably high recoveries from rock mining. Thus they imposed such penalties on impurities and lower than desired tin grades, that whenever a mineral processor improved tin recovery at the expense of lower- ing grade, such an improvement entailed a lower financial return to the miner. There was clearly a need for improved understand- ing of tin smelting, (at that time shrouded in secrecy) and develop- ment of techniques better suited to the treatment of lower grade concentrates. As well as the practical development, a start was made with the computer modelling of the smelting process, with the obiect of optimising the process parameters.

Jan 1, 1988

Following a decline in direct and indirect employment in the minerals industry between 2000 and 2003, the situation reversed in 2004 and employment rose by 12 per cent. Furthermore, there are forecasts of continuing employment growth in the minerals industry in the immediate future. For those of us charged with promoting the virtues of a career in the minerals industry this is encouraging news, as it provides us with the evidence to promote the increasing employment opportunities of a healthy and vibrant industry. However, for many others û particularly the employers in this industry û the news is not so rosy. The jobs are there, and in increasing numbers, but the workers arenÆt! Employers right across the industry are finding it increasingly difficult to fill vacancies with suitably qualified and skilled employees and the competition is becoming fiercer. In the minerals and energy sector, questions are being asked and solutions sought on the industryÆs ability to attract and retain a skilled workforce. From many quarters û industry, government and the education sector, calls for urgent action are becoming louder. The reasons for this are well known û the nature of the work, the remote location, perceptions of the industry, an aging workforce, the gender imbalance, the shrinking demographic of school leavers. It is the latter I wish to focus on û the Generation Y demographic û those who have recently left school, those who are in higher education or have recently entered the workforce, or those who are still at secondary school. These young people are the next cohort of potential employees for the industry. But our need for them appears to be greater that their perceived need for us! How do we engage them so they are informed about the industry? How do we inform and advise them so they are prepared to consider further education and training in disciplines and skill areas relating to our industry? How do we guide and motivate them to give it their best shot and work in it û at least for part of their working life? These are fundamental questions that many within the industry have been grappling with for quite some time. Let me share with you some of the strategies that the Minerals Council is implementing to address this issue.

Jan 1, 2005

By C Antonio, R Narayan, A Scheuermann, S Quintero, M Edraki, M Ziemski

Tailings are mostly loose material and can be classed as non-plastic sandy silts. They also tend to have low permeability, resulting in slow consolidation (settling) rates and low shear strength, even after consolidation. These qualities make them prone to liquefaction and, therefore, physical instability. In contrast, coarse waste rocks possess high shear strength and permeability when stacked in dumps. However, air and water flow-through the voids can cause acid mine drainage (AMD) with significant undesirable environmental implications. Combining the two waste streams before disposal by mixing presents a potential opportunity to harness the desirable properties of both waste streams. This practice is termed co-mingling and is prevalent within the coal processing industry. Co-mingling of metalliferous mine tailings is, however, a relatively new concept. By combining the coarse waste rocks and fine-grained tailings streams, the fine tailings tend to fill the voids between the waste rocks, reducing hydraulic conductivity and advective air (oxygen) flow into the rocks, thus possibly reducing acid mine drainage (AMD). Conversely, tailings are introduced to large frictional particles from waste rocks, providing reinforcement, stability, and possibly improved drainage. New separation methods are being introduced to the mining sector, which have the capacity to extract waste with significantly larger particle sizes. High Voltage Pulse (HVP) is a technology in which relatively coarse particles ranging in size from 30 to 100 mm are exposed to an electric pulse discharge. This pulse preferentially fractures mineralised particles while leaving unmineralised rock (gangue) intact. The stream can then be passed via a screen, with smaller mineralised particles reporting to the undersize and removing coarser unbroken barren particles, thereby eliminating waste. Coarse particle flotation (CPF) is another emerging new technology in metalliferous mining that applies flotation separation to coarser particles than conventional flotation. These new technologies produce different tailings (waste) streams with varying physical characteristics and possibly surface chemistries. This research aims to test new tailings mixtures by applying the co-mingling concept to blend the reject streams generated by these two technologies (HVP and CPF) with the tailings produced by conventional flotation. Combining different waste streams before disposal can improve stability and potentially reduce the acid mine drainage (AMD) rate, thus enabling early access to the tailings storage facility for rehabilitation and closure.

Aug 2, 2023

By A F. Idziak

The aim of the present study was an application of coal optical property measurements for analysis of paleostress field existing in fault zones of the Upper Silesian Coal Basin (USCB) during the coalification of organic matter. Measurements of vitrinite reflectance were carried out on coal samples taken near a hanging stope of the Klodnicki fault. Other samples had been taken in vicinity of the Krzyzowicki fault. The Klodnicki fault is one of the main tectonic discontinuities in the northern part of the USCB. It is postulated that its origin is related to the deep-rooted latitudinal discontinuity in crystalline basement of the basin. The Krzyzowicki fault is located in the western part of the USCB where fold tectonic style dominates. Vitrinite, one of the basic components of hard coal is generally considered as optically anisotropic material. Anisotropy of physical properties is induced mainly by stress, which arranges vitrinite structure. Vitrinite anisotropy can be described by an ellipsoidal model called reflectance indicating surface (RIS) which is a geometrical representation of the optical anisotropy tensor. The investigation of the RIS for vitrinite was carried out on coal samples. The apparent maximum and minimum reflectance values measured for a single vitrinite particle were plotted against corresponding bireflectance to construct the reflectance crossplot. Interpretation of this plot yielded the magnitudes of the RIS three principal axes. The data obtained point to differences in optical anisotropy of coal under the study. The coal samples taken from block tectonic zone near the Klodnicki fault had mean reflectance value of less than 0.80 per cent. Their anisotropy coefficients were about 0.1. Optical properties of coal changed from the biaxial positive in the western segment of the fault to the biaxial negative in its eastern part. It suggests that past tectonic stress was greater in the western part of the zone than in the eastern one. Coal originated from a fold tectonic zone at the vicinity of the Krzyzowicki fault has mean reflectance value much greater than from previous region (ÿ1.20 per cent). Its optical anisotropy coefficient is equal to about 0.07. It suggests that paleostress field was more isotropic. The presented study shows the usefulness of coal reflectance measurements in the analysis of paleostress field existing during coalification process.

Jan 1, 2003

The recommendations of a recent American report on "Better contracting for Underground Construction" are considered in relation to Contracting practices on major Australian projects by representatives Of the "classical trilogy" - the Owner, Engineer and Contractor.

Jan 1, 1976