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By J Tuma

Technical measurements are an integral part of research and development of new technical devices. Now they are also an integral part of production too, especially as a part of quality control systems. More new problems started with they applications up, like storing and following preservation of big data files. Many problems are also with processing of the measurement results, especially to be up to standards of ISO 9000 normative. It includes basic data about the measurement (structured data) and measurement outputs (huge data streams). Using database systems looks as good idea, because of structured measurement data and they processing. They were developed more concepts of database measurement system support during the research project MSM 272300012. It was decided to develop specialised measurement systems, on the base of experiments and experiences with they use in operating conditions. It proved to be wrong to develop general system, because of compound operating and long response of the system. And it is not possible to use these systems for mass production systems. The problem of data storing is not as easy to be answered, because of dependence on used technical devices. During realisation the measurement system for gearbox noise measurement are data stored to the database, because used analyser system PULSE (Brnel and Kjµr Co) is open structure and can cooperate with other software systems. Anyhow the data streams are not longer (after compression) than the Memo data type, in practical use increases the data file too fast (about hundreds MB daily). Therefore we must include a special supervisory system for administration and creating data files to the system. Nevertheless the used system MS-Access supports data files up to 1 GB, for practical application is better if the file size do not exceed the capacity of CD-ROM disc.

Jan 1, 2003

By A S. Bamber

Mining is the oldest industrial practice on the planet with a history dating back over 3000 years. Since the early iron age ores have been extracted for use in a variety of contexts by humankind, from domestic to military, transport and more recently for complex industrial applications. Mineral exploration and extraction has evolved from the early exploitation of primary metal occurrences in relatively small quantities such as iron, gold, coal and copper, to the bulk mining and extraction of highly complex polymetallic oxides and sulfides today. Since the industrial revolution, mining practice has evolved substantially to support an increasing range and quantity of required metals and to accommodate the increasing scarcity of high-quality sources of these metals. A common response to the increasing scarcity of mineral resources has been to expand production through simple economies of scale, thus diluting fixed costs. This approach, however, is increasingly ineffective in the face of current trends, that include increasingly complex mineralogy, increasing pressure on environmental footprint - energy in particular, and increasing scarcity of capital for the construction of presently popular æmega-minesÆ. This paper examines historical trends and current practice in mineral exploitation in the light of the current global revolution in social, environmental and economic values as the projects move towards a vastly different topology for the industry for continued success in years to come.CITATION:Bamber, A S, 2012. The mining industry needs to be shaken and stirred, in Proceedings Narrow Vein Mining 2012 , pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 26, 2012

By P Scott

Kaltim Prima Coal, an open cut coal mine located in Sangatta, East Kalimantan, Indonesia, operates two deep pits and two shallow pits with a truck and shovel operation. KPC produced 17 Mt of coal in 2002 by removing 120 Mbcm overburden. Geochemical investigations have indicated 20 per cent of total waste rock is potentially acid forming; ie it has the potential to create acid mine drainage (AMD). In the early years of the KPC operation, the presence of AMD had been observed in the mined out areas and in the waste rock dumps as a result of sulfidic waste rock exposure. A strategy for management of AMD from waste rock was implemented involving: sampling, analysis, modelling, selective handling and validation of final dump covers. Samples of the waste rock lithologies are collected from exploration drill holes for geochemical analysis to determine their acid generating potential. The geochemical database is used to develop the waste rock model for the life of mine pit areas. The acid forming and non-acid forming waste rock is delineated for each mining bench area for selective handling and placement within the waste rock dump during the operational stage. Each mining bench is sampled and assessed to validate the model predictions. The final dump cover is sampled to meet strict Quality Assurance requirements to ensure non-acid forming waste material is used in the outer cover of the dump. The geochemical investigation of the waste rock is integrated with mine planning to design and construct the waste rock dump to minimise the risk of generating acid. This process links the exploration stage, operation stage, and rehabilitation stage for each Pit area. The paper briefly reports the waste rock characterisation, waste modelling and strategies used for management of acid drainage by KPC.

Jan 1, 2003

By Kavetsy A

In surface mining operations, the ease with which a muckpile may be dug is a dominant factor in mining efficiency. Within broad limits this is largely independent of the fragment size dis- tribution, since the equipment used to move the broken rock is generally larger than in underground mines. In such cases, muck- pile shape and voids ratio within a muckpile heavily influence mine productivity. In a particular operation, the muckpile shape after blasting should be tailored to the digging equipment being used. A front- end loader is best suited to a low, flat-lying, loose muckpile, because of its fairly good mobility and small break-out force with its bucket. In contrast, a rope shovel lacks mobility, generates a much larger break-out force with its bucket, and fills its bucket in a vertical filling motion. Therefore, it is ideally suited to well fragmented, steep faces. In situations where a dragline is used, the requirement for a suitable muckpile depends on the operat- ing scheme of the dragline. For a conventional highwall key method the preferred work- ing level of the dragline is the same as the highwall, so that the dragline may sit over its key. In this situation, the ideal muck- pile shape involves relatively little displacement of the fragmented rock, with a minimal "power trough" at the back of the blast. In throw blasting, on the other hand, it is desirable to cast as much of the spoil as possible across the pit. It is then necessary to optimize the blast design by maximizing the throw percentage under any necessary constraints (e.g. damage, vibration, flyrock, explosive cost).

Jan 1, 1988

By T Martin, M Martin

Mining of sulfide-based ore deposits typically creates a potential for release sulfate and acid to groundwater, and many operating mines are thus predicted to require long-term post-closure treatment of groundwater. Toward the goal of selecting an optimal treatment, this paper compares costs of four demonstrated technologies for long-term treatment of sulfate-contaminated groundwater: in situ biological reduction (ISR), in situ permeable reactive barrier (PRB) composed of compost and zero-valent iron (ZVI), and two ex situ æpump-and-treatÆ technologies ù ex situ biological reduction, and ex situ nanofiltration with lime precipitation. Costs for each technology are estimated for treatment of a model aquifer system containing sulfate-contaminated groundwater, with the goal of treating 1 m3/min of groundwater from 1500 mg/L sulfate to a target level of 500 mg/L. (Metal removal is typically achieved by these technologies, and thus excluded from this analysis.) Costs are estimated for each technology as a function of treatment duration (ten to 60 years) and, for PRB and ISR, required replacement frequency (ten to 60 years). Estimated costs include capital and operation and maintenance, using a seven per cent net discount rate. Results indicate that ex situ technologies (biological reduction and nanofiltration with lime precipitation) are the most expensive. In situ technologies may be much less expensive, with PRBs having by far the lowest potential cost, followed by ISR as the next least expensive. However, actual costs for the in situ technologies are very sensitive to poorly constrained parameters, particularly the ZVI content of the PRB, and the effective life of PRB and ISR systems. This large cost uncertainty supports delaying remedial actions where viable, and suggests that feasibility analyses are generally warranted for specific applications to focus on these sources of uncertainty.

Jan 1, 2003

The perception of the mining industry in the Australian community has changed considerably over the last four decades. This has been partly brought about by changing values and expectations of the Australian community as well as by global factors. The legal environment for the Australian mining industry has undergone significant changes. Among them, the High Court's Mabo decision which confirmed native title rights as part of the common law and environmental legal developments are dealt with particularly. It is suggested that the Australian legal environment is not necessarily the prime cause for Australian mining companies taking their investment off shore. This is a summary on how native title impacts on land tenements and some of the major issues that emerged since the `Mabo decision' and the Native Title Act 1993 are discussed. Environmental legal developments have resulted in liability facing directors and senior management in compliance matters .and in operating mining and other businesses because of changes in community expectations. In the next decade it is suggested there will be many drivers for more changes in the legal environment. Some of these are touched on including the changing roles of the Commonwealth and State Governments, the High Court as -law-makers and the changing relationships with indigenous people in Australia and in overseas countries. The changing legal environment for mining demands a national approach in many areas on the proposition that resource based industries are part of a national industry. The uniform law approach among the States has been taking place but this needs to further. An appropriate task force should be forward to review the entire legal structure and regulations affecting mining on a national rather than a State basis . The mining industry will need to work with expectations of a changing community which have powerful, but sometimes contradictory, interest groups.

Jan 1, 1997

By J Vann, S Jackson, O Bertoli

Ordinary kriging and non-linear geostatistical estimators are now well accepted methods in mining grade control and mine resource estimation. Kriging is also a necessary step in the most commonly used methods of conditional simulation used in the mining industry. In both kriging and conditional simulation, the search volume or ækriging neighbourhoodÆ is defined by the user. The definition of this search can have a very significant impact on the outcome of the kriging estimate or the quality of the conditioning of a simulation. In particular, a neighbourhood that is too restrictive can result in serious conditional biases. The methodology for quantitatively assessing the suitability of a kriging neighbourhood involves some simple tests (which we call æQuantified Kriging Neighbourhood AnalysisÆ or QKNA) that are well established in the geostatistical literature. The authors argue that QKNA is a mandatory step in setting up any kriging estimate, including one used for conditioning a simulation. Kriging is commonly described as a æminimum variance estimatorÆ but this is only true when the neighbourhood is properly defined. Arbitrary decisions about searches are highly risky, because the kriging weights are directly related to the variogram model, data geometry and block/sample support involved in the kriging. The criteria to look at when evaluating a particular kriging neighbourhood are the following: the slope of the regression of the ætrueÆ block grade on the æestimatedÆ block grade; the weight of the mean for a simple kriging; the distribution of kriging weights themselves (including the proportion of negative weights); and the kriging variance. Outside of the technical geostatistical literature, there is little in the published domain to describe the nature of QKNA and no practical presentation of case examples. In this paper we attempt to redress this by setting out the calculations required for QKNA and defining some approaches to interpreting the results. Several practical worked mining case examples are also given. Finally some comments are made on using the results of QKNA to assist with block size selection, choice of discretisation and mineral resource classification decisions.

Jan 1, 2003

By D V. Boger

The use of chemical additives to initiate such processes as particulate separation through flotation or dewatering through flocculation, is common in the mining industry. The dosing of additives is none the less poorly controlled from a process control viewpoint and it is perhaps fortuitous that over-dosing or misuse of chemicals is rarely catastrophic to the production cycle. In many cases, such events would go undetected if it were not for economic considerations. Recently, the advent of orebodies with finer mineral disseminations and the push for greater efficiencies in both production and tailing disposal have resulted in the need for greater control of the dosing and utilisation of chemical additives. The need to grind at higher pulp densities and to finer sizes and to dewater to higher solid contents are but two examples that require a more stringent understanding of the true role of additives in controlling the rheology of suspensions and the influence of additives on the surface chemistry of particles. The inter-relationship between the surface chemistry of particles and the role of additives in controlling suspension rheology is now well understood for systems in which the average particle shape in the mixture is spherical or close to spherical. Luckily, this is the case for a large number of systems in the mining industry and the true role of typical additives in these systems will be explored. Difficulties arise for suspensions containing clays or other platey or needle shaped minerals and in many cases, quite small quantities of platey minerals dominate the rheology of suspensions. The role of additives in controlling the rheology of asymmetric particle systems is more complex but the effect of the additive in changing particle alignment in solution is the key to understanding suspension behaviour. The manipulation of the rheology of asymmetric particle systems will also be explored.

Jan 1, 1998

The sole reason for a mine to exist is to extract the finite mineral resource. Accurate grade control is critical to the economics of any mine. If grade control is not optimised, then no matter how good the downstream processes are, the full potential of the operation will not be realised. The detailed implementation of grade control varies but typically consists of sampling and assaying to determine the location of the ore zones. A lot of time, money and effort are spent defining the location of the ore as accurately as possible à but then it is blown up! The effect that blasting has on grade control is rarely adequately accounted for when the rock is excavated because there has never been an accurate and practical method for measuring blast movement. This paper draws on over six years of research into measuring and understanding blast movement, which started at the Julius Kruttschnitt Mineral Research Centre (JKMRC) of the University of Queensland. The research has made a unique contribution to open pit blasting by helping to develop a practical tool for measuring blast movement, which was then used to improve the understanding of three-dimensional blast movement dynamics. However, these achievements would be of largely academic interest without taking the final step of using this technology and knowledge to account for blast movement by translating the ore polygons in response to the measured movement vectors. This paper provides an overview of blast movement but focuses on one site where blast movement was measured during three separate periods, with significantly different orientation of the mineralisation on each occasion. The theoretical ore loss varied from nine per cent to 24 per cent. The differences are primarily due to the orientation of the ore polygons relative to the direction of movement. The optimum grade control solution is a combination of accurately accounting for blast movement and designing appropriate blasts.

Jan 1, 2009

As near-surface underground mines progress deeper, the inevitable question is whether to convert from truck haulage to shaft hoisting. The desire to defer capital expenditure frequently delays investigation of the shaft option, or deferral of a decision to start shaft sinking, unless the shaft option is clearly significantly better than trucking. By the time increasing depth makes trucking uneconomic, there may then be insufficient resource remaining to justify a shaft, and the mine must close. However, had the shaft been built earlier, its lower operating costs would have permitted the mine to continue to greater depths. This paper presents a methodology for investigating the shaft versus trucks decision. As well as the typical analysis of which option is preferable at the time the analysis is conducted, the process presented illustrates how the timing of the decision to sink a shaft is critical. The paper shows how to identify the latest date at which the decision to sink a shaft can be made, after which time the shaft option will not be economic. It also illustrates how to assess the resource that may be required to justify the shaft. Considering this in conjunction with the latest decision date, implications for the companyÆs exploration program are discussed.

Jan 1, 2005

By Breen AM, Phelan JM, Doherty RJ

Early in 1990, Pancontinental Resources (Base Metals) Pty Ltd commenced flotation treatment of ore from the complex copper-lead-zinc sulphide orebody at Thalanga, 65 km west of Charters Towers in North Queensland. The orebody consists mainly of primary sulphide ore but also contains a substantial proportion of supergene ores which are being processed during the first year of operations. The supergene ores are of three main types, designated as A, B, and C. Supergene A ores are essentially copper ores, containing little lead and zinc, while B and C ores are copper-lead-zinc ores with different degrees of alteration of the original chalcopyrite and different ratios of copper to zinc content. Copper is present in the supergene ores mainly as chalcocite, digenite and covellite. Lead and zinc occur mainly as galena and sphalerite respectively. This paper describes the development of flotation plant practice, aided by laboratory testing, to process the supergene ores. The major challenge in treating these ores is that a varying proportion of the sphalerite is naturally activated and is not easily depressed in flotation by the conventional zinc depressants.

Jan 1, 1991

This address was delivered at the Annual Conference Presidential Dinner held in Sydney on 11 July 1988.The Australasian Institute of Mining and Metallurgy brings together, voluntarily, people with a professional interest in the disciplines and skills which are employed in the mineral industry, and in relation to that industry.We come together because we have a mutual interest in improving what is done by the mineral industry, in all its aspects. It is this sense of continuing improvement, of doing better, of doing as well as we can, as our knowledge and skills improve, that unites us in creating and fostering a professional association of likeminded people.We know from our professional training and experience that enormous progress has been made, at an ever-increasing rate, in the mineral industry, particularly this century. We know that the mineral industry has played a very major role in providing the means by which so many more people survive to live longer, healthier ,and more interesting lives, than ever before. Indeed, together with the oil and gas industry, which is an integral part of the mineral industry but has achieved its own commercial distinction, it is fair to claim that the mineral industry has played the major role in providing the means for the advancement of the human, quality of life.We do not need to make any great claims on human society in consequence of our statement of these contributions. The facts, for those who are aware of them, speak for themselves. Our more modest interest, as members of our professional association, is to look to the future, while conscious of our heritage as a guide to what more might be done, in that future.We certainly do not claim that this indisputable contribution made to human welfare by the mineral industry gives us some moral position of superiority from which to claim greater support or understanding from the wider community of people.On the other hand we know that as members of the mineral industry we have a responsibility to do what we can to help other people to be aware of, and to understand the significance of, those facts which will only speak for themselves if we take the trouble to make them known. And we have a number of organisations. The Institute itself, The Australian Mining Industry Council, the various State Chambers of Mines, the industrial relations body, The Australian Mines and Metals Association, and others, each of which in its own way endeavours to add strength to the individual efforts which we each should make.We may look at these facts about our mineral industry as simple dry statistics, even with their undoubtedly improving trends, or we can see them, and portray them to others, as expressing something which is much more. We can portray them as expressing the outcomes of our professional determination to strive to do better, whatever it i,s we find ourselves doing in this mineralindustry.We may seek to describe our efforts as being in pursuit of excellence, or by other such high-sounding phrases, but I prefer to describe those efforts as simply our strivings to make everything we do better next time-much as the dedicated golfer tries to do, but with, may I suggest, more evident success achieved in the mineral industry; which is one reason why I don't try to play golf.May I suggest to you that trying to do better, is very simply the true basis of professionalism? We are trained and practised to see the opportunity for improvement-not to be static in a world which we know is changing so rapidly in every aspect around us. We must be dynamic, which means optimistic, about improving the world in which we find ourselves.

Jan 1, 1988

Water Savings and Coal Product Compromise

Sep 13, 2010

A saturated, metal-free solution of alum can be used as a fiocculant to speed up the sampling procedure during a geochemical survey of stream silts.

Jan 1, 1969

An Investigation of Cobalt Recovery on a Complex Oxidation Mine with High Per Cent of Mud

Sep 13, 2010

The law relating to the Treaty of Waitangi is developing rapidly at present. A number of separate, but related, developments can be identified.

Jan 1, 1988

This paper shows how small calculators can be used for ball mill simulations. Two calculations are examined, the first to calculate the mill parameters and the second to predict the mill product. In the case of small programmable calculators the programs for two common models are given.

Jan 1, 1976

Zinc enters into solution on aeration of sphalerite in deionised water. It has been observed that less zinc dissolves in a copper vessel than when the same operation is carried out in a glass vessel of similar shape and size.

Jan 1, 1980

A new classification of subduction related (epithermal- / mesother-mal) gold mineralisation styles based on the tectonic framework they occur in, has been found helpful in practice. It offers a ratio-nalisation of exploration efforts during all stages of work.Methodology on the ground during first pass- and follow up explo-ration which has been found effective for the various mineralisa-tion styles is being briefly outlined.

Jan 1, 1990

In the wake of the United Nations Conference on Environment and Development (UNCED) held in Rio de Janeiro in June 1992, evolved AGENDA 21. This document which was adopted at the Conference, provides a global action guideline for sustainable development into the 21st century.Sustainable mining requires a complete understanding of the `mineral cycle', including government legislation, mineral exploration, mining operations, rehabilitation, product use, re-cycling and waste disposal that takes into consideration associated social and environmental considerations and achieves economic objectives.

Jan 1, 1993