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By Adeloju S, McQuade CV, Riley SJ

Metal contamination of sediments can be an issue for minesites discharging water. Water sampling of receiving waters is frequently undertaken. Sampling and analysis of sediment is less common. The variability of receiving environments makes the formulation of a generic sediment sampling strategy virtually impossible. Each situation needs to be carefully assessed before sampling is undertaken. This paper outlines the approach taken for one such survey.The main factors that need to be considered in a survey of surficial sediments are sample representativeness and sample variability. A simple data set from one site within a regional survey is used to illustrate the importance of these factors. The metal content of sediment is shown to vary significantly over small spatial scales.The variability associated with the spatial distribution of samples within a site is shown to be the most significant source of variability in the study. This variability could bias the results of a study if not planned for in the sampling methodology. Taking multiple samples from within each site (sub-site samples) and combining the data gives a more representative indicator of overall conditions than a single sample. The optimum number of sub-site samples to be taken from each sampling site was found to be 15.It is shown that a composite of sub-site samples can give a good indication of the average site metal content, while considerably reducing the sample preparation and analysis effort.

Jan 1, 1998

By K Gilliland

The past decade has seen the widespread implementation of computerised real-time operational management systems in open pit mines. While these systems have made a significant impact on operational efficiency at a process level, surprisingly little work has gone into integrating these systems with other IT systems, including those used for tactical planning and enterprise resource planning. As a result of this gap in the information hierarchy, the goal of optimising an entire operation, or multiple operations, remains elusive. Implementation of computerised operational management systems in underground mines has been much slower. This is a significant, though often overlooked, reason why the productivity for underground mining is generally so much lower than for open pits. The historical reluctance to implement computerised operational management systems underground can in part be attributed to the underground environment, particularly the difficulty in establishing effective communications. Another factor retarding the implementation of systems underground has been the perception that the nature and scale of underground mining does not lend itself to computerised operational management. This perception can be challenged, not only by a process level examination of the underground mining, but also by a holistic examination of the entire industry. In recent years, the mining industry as a whole has destroyed rather than created wealth and underground mines are major culprits. The degree of value destruct has been more pronounced with underground mines, as the usual problem û low commodity prices û has been exacerbated by the harsh environment, low productivity and a æfog of warÆ no longer generally found in open pits. Faced with these realities, underground mines will have to adopt modern management tools or suffer extinction at the hands of an unsympathetic investment community. All is not gloom and doom, however. Technological advances have largely overcome the difficulties associated with the underground environment. As a result, there is a small, but growing, number of underground mines using computerised operational management systems to directly improve the bottom line. Much greater improvements can be realised if the industry takes advantage of the recent convergence in technology, to integrate process information with tactical and enterprise resource planning systems in order to provide a solid platform for all decision-making. This would result in the æeÆ mine. Given that the underground fraternity is essentially starting with a blank sheet, they have the opportunity to æsteal a marchÆ on open pit mines, who may be constrained by legacy systems. The benefits of the æeÆ mine are presented through a hypothetical case study that examines the shortfalls of the non-æeÆ mine. The paper ends by presenting a future vision for the æeÆ mine.

Jan 1, 2000

Criteria for the manipulation of commodity markets are discussed. Against the economic background of the past twenty five years actual attempts to manipulate markets are evaluated.

Jan 1, 1985

The seemingly insatiable world demand for mineral and energy products is continuously pushing out the frontiers of exploration and development in countries around the Pacific Rim.

Jan 1, 1990

The first 12 m diameter rakeless thickener in the Australian gold mining industry was installed to treat plant tailings at the St Ives gold plant in April 2000. The plant processes approximately 3.2 M tonnes of ore producing about 430 000 oz of gold per annum using conventional crushing, grinding, gravity and carbon in pulp processing methods.The main benefit sought from the thickener was to improve water recovery in the plant and provide water for a 55 000 oz per annum heap leach operation. The thickener design indicated that more than 128 m3/h of overflow water could be returned directly into the plantÆs water circuit, relieving the demand on the borefields. The resultant surplus in the water circuit would then be available for the heap leach project. Based on laboratory and pilot plant scale tests conducted by EIMCO the thickener was designed to handle up to 700 m3/h of tailings slurry (450 tph of solids) with a 40 per cent oxide component in the ore blend. The normal plant throughput is 565 m3/h of slurry (400 tph of solids). Gold mineralisation in most areas at St Ives comprises quartz-sulphide vein and breccia lodes with common albite-biotite-chlorite alteration assemblages. There are well developed supergene gold horizons in the clay-oxide profile above most of the deposits (Osborne, 2002). This results in a wide variety of ore types being treated. At times 40 - 50 per cent of the ore may be oxide in nature. After some commissioning difficulties associated with instrumentation, the thickener has performed satisfactorily although it has not reached its design capacity. The maximum density achieved under normal operating conditions with 20 per cent oxide ore is about two per cent below the design. The thickenerÆs performance deteriorates further with increasing amounts of oxide ore in the blend. The thickener has provided sufficient water for the successful operation of the heap leach and has also provided some down stream benefits for the gold plant by way of pH and cyanide conditioned thickener overflow water.

Jan 1, 2002

THE following notes simply sum up the writer's experience, which extended over a very busy period of some three years, dealing with wolfram ores and concentrates. The three methods for the estimation of tungsten that are discussed below are well known, but these results of their trials and comparison under technical conditions may be interesting. Method I. The routine procedure for the assay of rich wolfram ores or concentrates was as follows: Take 1 gram of finely-ground sample; digest with HCl and HNOs for about 2 hours, evaporating down to near dryness. To the remaining 5 cc., say, of liquid, add water, warm or boil for 1 to 1.5 hour, filter through a small filter paper, and wash the beaker and the insoluble matter with hot dilute HCl. It is best to keep the bulk of the insoluble matter (WOs, Si02, etc.) in the beaker at this stage. Then plaee a weighed porcelain dish under the filter funnel and wash the beaker and the filter paper with successive small quantities of strong NHOH, finally bringing all the insoluble matter on to the filter paper, and collecting the ammoniacal filtrates in the porcelain dish (S). Then place the filter paper with the insoluble matter in a porcelain crucible, dry and burn off the paper, cool, and brush the contents of the crucible on to an agate mortar, grind it to flour, and brush this back to the original beaker without loss. In the absence of draughts this can be done safely. Re-treat this residue with' acid and ammonia as above, running the second ammoniacal filtrate into the previous porcelain dish, which in the meantime has been heating on a water-bath.Finally evaporate to dryness on the water-bath the combined ammoniaeal filtrate, and then heat gradually to a red heat over a Bunsen burner, cool, and weigh. Then the contents of the porcelain dish give the WOs (tungstie aeid) direcvly (5).The final filter paper and insoluble matter may be ignited in a porcelain crucible, thus giving the "insoluble matter." If the ore...

Jan 1, 1922

Many of the discrepancies that appear when comparing the results of reducing machinery are due to the nature of the materials reduced and the conditions under which they have been treated. It is therefore necessary that manufacturers should employ standard materials in their tests that sufficiently approximate the substances to be ultimately treated if the information is to be of any value to the purchaser. Another advantage to be gained by employing universal standard materials is that by their means one is enabled to compare the relative values of different types of machines. At present much of the data meted out to the public is insufficient to enable them to judge fairly. Of course the best test would be to send some of the stone tor which the machine is required, to be treated by the various crushers in the market that are likely to be suitable for the purpose, but this is not always possible. It would not take long to become accustomed to judge of the value of a machine for a specific purpose if it was guaranteed to work a certain quantity of some standard rock, even if that standard were not identical with the material to be treated.There are many points to be considered before selecting a machine, such as the size of the rough stone it will take, the size to which it will reduce it the proportions of various grades made when crushing to pass through a given mesh the form of the delivered particles the time taken to treat a+ certain quantity the horse-power required to drive the machine, both when loaded and unloaded whether constructed to crush wet or dry the wear and tear of the machine its total weight and weight of the heaviest part the cost of machine what attention it required whether the wearing parts are readily replaced, and several other points common to all machinery. 'When considering these varying quantities, we can tell at a glance certain machines that are suitable for a particular sort of work, and can then compare those belonging to the same class, thus avoiding errors made purposely or through ignotance by persons interested in different machines, who frequently compare machines originally constructed for.

It is indeed a pleasure to be here this morning to open the 4th Mill Operators' Conference. It is no mean feat to organise such an event and I would like to congratulate the committee for the work that they have done. I am sure that the Conference will be an outstanding success. I welcome overseas visitors and hope that they gain and share in the openness of this Conference. There is personal satisfaction for me to speak to you as a mining engineer addressing a large group of metallurgists and mill operators. I would have thought that it would be impossible for a mere mining engineer to inform a metallurgist of anything. I will desist from using such derogatory terms as "xanthate munchers", "bubble makers" and "glorified mathematicians". Terms of endearment as these may not be seen with much equanimity. Such is the warm association that the two professions have enjoyed over the years. The economic climate that we at present face is a major problem to all of us. I wonder how many people here come from mining operations that are in trouble financially or that are cutting back in one form or another. This is the recession that we needed to have. When the world's greatest treasurer can tell us that then we truly have a lot to fear. The present downturn can be seen as a normal adjustment in the cycle of our business. Yet the world does not experience such severe adjustments as frequently as we experience ours. The root cause for the regular adjustments can be placed at the feet of inflation. Until the politicians of this country of ours can come to grips with inflation, we will continue to experience downturns on a 5 to 7 year cycle. This, in my opinion, is the basic reason why we appear to experience more downturns than the rest of the world. We simply price ourselves out of the market. This takes about 5 to 7 years to be highlighted and then we need to make adjustments. However, this recession is worldwide. The adjustments usually take the form of redundancies, retrenchments and early retirements. What is the solution?

Jan 1, 1991

It is indeed an honour to address the perth branch of the australian institute of mining and metallurgy and to have the opportunity to talk to you about the future role of upgraded ilmenite on t102 feedstock supply and demand. There have been many papers written on upgraded ilmenite supply and demand and now I would like to share with you QIT's view of the situation first, a word about demand, although I will be talking principally on the supply issue. The principal use of t102 is in the manufacture of pigments which, in turn, are used in paints, plastics, and the paper industry together with a few miscellaneous uses, while a further b% or so of t102 minerals are consumed for the manufacture of titanium metal and for the manufacture of welding electrodes. the total demand for contained t102 is of the order-of 3 million tons per annum, and the general consensus in the industry is that growth rates should be of the order of 2% annually- it is against this backdrop that suppliers must compete with one another and produce least cost materials for the pigment industry. At the moment, supplies are relatively tight, but the generally slow growth in demand coupled with the abundance of titanium bearing minerals should ensure that long term the reverse is generally true. Now, let us examine the supply situation. Titanium is the 9th most abundant element in the earth's crust, so the problem from the producers` point of view is not one of scarcity of titanium minerals, but of how to extract most economically t102 feedstocks from a wide variety of choices- up to the present, all titanium feedstocks are being derived from either rutile or ilmenite rutile, at about 95% t102 content, is indeed a premier raw material which does suffer from potential scarcity and rutile supplies will likely be a diminishing factor in future decades- whereas ilmenite, a combination of iron and titanium oxides found in varying ratios, may be found in huge quantities all over the world.

Jan 1, 1986

It is a commonplace of our industry that prices of most minerals have been historically weak during the 1980s. The International Monetary Fund's index of prices of metals fell 25 per cent between 1980 and 1982, rose slightly in 1983, and has since fallen further. In December last year it was 37 per cent below its 1980 average. The few temporary exceptions to the mineral industry's malaise highlight the excess capacity, which largely explains the weakness of prices. The industry has painfully come to recognise that more satisfactory prices will not be restored until supply capability and demand move back into better balance. Mine capacity was installed in the expectation of much faster growth of demand than has occurred. For a variety of reasons mine and plant closures have been insufficient to restore equilibrium to the market-place. The industry may, therefore, have to resign itself to continued weak prices for some years more, at least by the yardstick of the 1970s. Growth rates of demand have slackened off in line with economic activity, and in response to continuing substitution and technological improvements. To the extent that the recent weakness of oil prices stimulates the industrial countries' activity, demand for non-fuel minerals may grow faster than most forecasters now predict. It is, however, much too early to say how long the weaker oil prices will persist, and even more difficult to estimate their probable effects. In typical post-war business cycles the usual response to recession was to batten down the hatches, and ride out the storm. Sooner or later, and probably sooner, demand resumed its previous trend path, and prices recovered. The market, in effect, bailed mines out of trouble; the more efficient could make attractive pre-tax profits whilst even the poor to mediocre could earn a satisfactory living. Prices rose at least as fast as general inflation, and in the early 1970s much faster. In retrospect those price rises of the early 1970s were historically abnormal but they did not appear so in the prevailing inflationary climate of the time. When the market failed in the early 1980s many of the hardest hit companies looked for scapegoats.

Jan 1, 1986

In 1939 at the annual meeting of the Australasian Association for the Advancement of Science, held at Canberra, a paper was contributed by E. de C: Clarke and H. A. Ellist in which a plea was made for more "facts" concerning metasomatism near ore-bodies in Western Australia. From time to time writers here, and in other parts of the world, have discussed the alterations in wall rocks of various reefs and lodes, but little has yet been attempted in the matter of accumulation of quantitative data, both chemical and mineralogical, and in the correlation and comparative study of this data. Such a detailed comparative study is needed to determine the economic value of a practical application of our accumulated knowledge of the phenomena of metasomatism.When in 1939 the opportunity offered for an examination of the core from 4 bores recently put down by the Big Bell Mines Ltd., to explore the ore-body of the Corinthian G.M. 10 miles N.W. of Southern Cross, Western Australia it was hoped that some small beginnings might be made of an accumulation of comparative and quantitative data regarding the metasomatism of the wall rock immediately adjacent to this ore-body.By the courtesy of the Big Bell Mines Ltd., the core from the 4 bores was delivered to Survey Headquarters, Perth;in the middle of June, 1939 and copies of assay plans of part of the underground workings at Corinthian, and of the results of assays of the bore cores, were also supplied by the management of the above company.It was not, however, until March, 1940, that it was 'found possible to investigate the core. At that time the writer's colleague, Mr. R. S. Matheson, conducted a: megascopic examination of all the bores and selected material from two of these for possible future chemical analyses. Late in 1940 the writer commenced a microscopic petrological examination of this material.AIM OF THE INVESTIGATIONThe object of the petrological part of this investigation was to determine whether from a megascopic and microscopic examination of the core, any evidence could be obtained indicating changes, in mineralogical composition...

Jan 1, 1942

Botanical exploration has identified many plant species that naturally accumulate very high concentrations of elements, particularly heavy metals. The enormous potential applications of some of these species to remove metals from soil (phytoextraction) are slowly being realised. The discovery of hyperaccumulation has resulted in considerable research into applications for removing contaminants (phytoremediation) or more importantly, in the context of this discussion, for commercially æfarmingÆ metals (phytomining) from metal-bearing soils. Currently published phytoextraction models estimate Ni yields using Berkheya coddii (a South African nickelophyte) are approximately $US 750 ha-1, excluding the cost of processing. Research indicates that B. coddii will also accumulate significant amounts of Co, resulting in a considerable increase in the value of the crop. Modification of the substrate by acidification, fertilisation and/or chelation indicate fruitful avenues for improving this yield by increasing the extractability of the target element, elevating biomass production rates and/or rendering other contained heavy metals extractable. Plant uptake of more insoluble elements, such as Au, may be induced in many plant species using chemical compounds. These chelates applied to the soil, form soluble complexes with poorly soluble metals forcing them into the soil solution. Plants may then accumulate these metal complexes through transpiration. Research has achieved foliar Au concentrations of 78 mg kg-1 in Iberis intermedia, 56 mg kg-1 in Brassica juncea and 9 mg kg-1 in B. coddii (on a dry weight basis). Therefore in theory B. coddii could phytomine a soil containing modest concentrations of Ni, Co and Au to yield 116 kg Ni, 36 kg Co and over 6 oz Au ha-1 at a current value of $US 4000. Root crops have also shown promise in chelate assisted Au accumulation (eg 6.8 mg kg-1 in Beta vulgaris and 118.5 mg kg-1 in Raphanus sativus). Phytoextraction, in its varied applications, is rapidly coming of age as a technology having considerable potential for application in environmental science and the minerals industry. Phytotechnology employs unique plant biochemical behaviours in the rhizosphere, driven by the sunÆs energy, to seek out and concentrate low levels of heavy metals at very low cost.

Jan 1, 2002

To explain in any depth the industrial relations of Broken Hill I believe that it is necessary to trace some of the many happenings that created the present industrial climate. While appreciating that our relations with the local industry are relatively good, it must be pointed out that to preserve and improve this present situation a duty is owed to everyone connected with the industry (workers, share- holders, etc.) by management and unions to see that just and reasonable agreements are found for any disputes. If the companies ever take the local position for granted it would soon die, killed by someone who may get some short term benefit, but who would lose something of incalculable worth in the long run. Similar- ly if the unions were to adopt some of the "wild cat" methods adopted in other parts of

Jan 1, 1975

Management at all levels continually strive to optimise, or make the most of resources available to them. Daily, decisions are being made on how to most efficiently locate and exploit an ore body, then process and market the recovered metal. At one level this optimisation process in the Australian mining industry appears to be successful, for example, witness the improvement in productivity and reduction in operating costs through the 1980s. Yet, at another level the industry's performance has been appreciably below expectations as measured by rate of return criteria. Companies likely to exhibit superior performance are those that are able to co-ordinate, through good planning, the optimisation process at all levels of the organisation. An important role for general management is therefore to provide the context or boundary conditions in which optimisation can Proceed.

Jan 1, 1991

Partnering has come to prominence in the Australian construction industry in a formal sense this decade. The high level of disputation in the building and civil construction industries in the 1980s drove its development in both Australia and North America. PartneringÆs use has been most prominent in the construction industry, particularly in the civil and construction sectors of the industry. It has found favour in some mining development projects, one of the most notable being BHP MineralÆs Cannington project in NW Queensland. This paper examines the requirements of successful partnering agreements and describes in detail the mine development partnering agreement at Cannington. In particular, the paper discusses the authorÆs experience and recommendations for partnering to avoid contractual problems and achieve win û win project outcomes for all parties to major mining projects.

Jan 1, 1999

Human resources (HR) practitioners use a general suite of tools that they adopt to suit their company needs and profile. This paper will cover the main areas of a selection and recruitment process from applying for a job, resumT writing, participating in an interview finalising the job offer. A holistic recruitment process has many facets to it. These processes can be quite sophisticated and technical but at the end of the day they are designed to identify talent. A recruitment process will generally include: ability testing (usually online);telephone interview;face to face interview;behaviourally based interviews;psychometric assessments;presentations;simulations (independent or team based); and assessment centres, etc. Understanding the basis of these tools will go a long way to prepare you for the job market, enhance your performance in a recruitment process and stand you out from the pack.

Jan 1, 2008

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

In both exploration and mining, the laboratory is often seen as a cost rather than a profit centre. The aim in most mining companies is to increase profits by reducing costs, so the budget for the laboratory is under constant pressure.There is another option; to see the laboratory as the brain of the operation. By lifting the status of the laboratory and treating it as a profit centre, mine costs may be reduced in other ways, e.g. reduction in milling costs. This change of status will require investing more capital in better equipment, more training for employees and more employees to carry out project research.There are many examples of major costs being incurred because of inadequate laboratory work. Conversely, by spending more money on laboratories and their activities, overall costs can be reduced or profits enhanced.

Jan 1, 2002

By G B. Siddall

The paper examines the current state of equipment and circuit design, with reference to Australian practice. Following a review of the changes in milling applications over the last 15 years, developments in mill design are examined. Current issues include trunnion versus shell support; drive type and economic analysis for comparison of the various systems; the efficiency of the mill discharge system for slurry and pebble removal, and lining configuration. Peripheral problem areas such as pebble crushing and classification are briefly examined. Circuit design issues are reviewed. The decision to modify the traditional primary crushed feed is examined with reference to recent and proposed installations. A retrospective look at fully autogenous installations and their successes is presented, and current views on increasing throughput are assessed. Finally, future developments are anticipated in mill design and control, and competing processes are identified.

Jan 1, 2002

By M Akbarpour, M Osanloo

In mining industries, materials handling costs represent a significant component of the operational cost. A variety of methods have been applied in surface mine equipment selection in order to select the suitable loading system with the lowest loading operation cost. These are queuing theory, bunching theory, linear programming and genetic algorithm. Among them, genetic algorithm is a simple method and applied for preliminary selection of the loading system. In this study, gathering information from anomaly No 2 of Gol-e-Gohar iron mine of Iran, loading system (number and its capacity) has been optimised by genetic algorithm. The study results showed that two shovels 8.25 m3 are required for the removal of 60 million tonnes of overburden. After removal overburden, these two shovels contribute to the extraction of 42 million tonnes of ore with a stripping ratio of 1:1.

Jan 1, 2007