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By Blackwood R. L, Crichton G. P

In recent years, the value to Australia of the introduction of a system of resource rent taxation on the mining industry has been frequently debated. The forms that this rate of return based tax could take, and the impli- cations on government revenue and mining com- pany profitability have been discussed at some length. Further, the selective application of this taxation scheme to certain mining industry sectors has received considerable attention. This study takes the form of a survey of the taxation history of one significant Australian mining venture, the Mount Lyell Mining and Railway Company. The conditions faced by this company during its history are used as a base for the imposition of rent taxation schemes. Comparisons are drawn between the historical taxation liability of the company and that which would have been incurred if a resource rent form of taxation had been in existence. From the results of the study, it can be concluded that while the company can be con- sidered to have been a successful enterprise during most of its history, it has not achieved a level of profitability which would warrant the collection of any form of excess profits Tax.

Jan 1, 1979

The title of my presentation is `Nursing One's Resources', words that fit a young organisation like Ross Mining and words we had to apply to reach our current level as a company. To get to where we are, we had to nurse, foster and treat carefully all our available resources in the widest sense of the word, namely: ò a stock or supply that can be drawn upon (funds, mineral resources, human resources); ò the means available to achieve an end; ò skills in devising expedients; and ò practical ingenuity. I do not claim that Ross Mining is now the perfect mining company. However, we have become a profitable, dividend- paying, gold mining and exploration company which is to our knowledge, currently the cheapest gold producer on the Australian continent. Nursing our resources got us where we are and will guide us in our future development. The words `nursing one's resources' are I feel particularly applicable to mining-as I like to argue that the extractive mining industry has a social responsibility to optimise the metal output and value from each orebody which is being exploited, and preferably leave no metal behind. Likewise, a modem company cannot survive into the future without maximising and optimising its human resource potential. In this presentation I would like to present a number of actual examples of nursing one's physical and human resources. Before I do that, I will give a brief background to Ross Mining. Ross Mining NL is a young Queensland-based company that gained its stock exchange listing in September 1987 and that poured its first gold in 1989 from its own developed Belyando Mine, located in Central Queensland. We have now reached the stage of a medium-size gold producer, producing approximately 70 000 ounces of gold per year, mainly from the Yandan Gold Mine, also in Central Queensland. Our production is set to increase to over 100 000 ounces in the near future. Recent increases in our resource base have secured us a future of ten to 15 years. As a young, newly listed company, we faced all the dangers that most new small floats do as a new entrant into an established industry. However, one advantage of being young and perhaps naive, is summed up by the following Zen Buddist saying: In the beginner's mind there are many possibilities, in the expert's mind there are few. A mining company's main assets are the sum of its resource base and the skills and talents of its people. Attempting to optimise both the physical and human resources within the company has been to-date the key to our success. The first example I would like to present is linked to the exploitation of the Belyando Gold Mine in Central Queensland.

Jan 1, 1995

By Golubkov OL, Fedotov PB, Shkylar FR

One of the fundamental parameters of the race- way is its extent (a{ o), which has a significant effect on the distribution of gas and material flows in the lower region of the furnace. pp The known relationships for determination of aC o in most cases link the length of the raceway with the parameters of the blast, while the para- meters of the coke layer, in which the raceway is formed, are either ignored or else expressed in terms which are difficult to determine experimen- tally. Furthermore, the coke combustion propert- ies are not always taken into account in current blast furnace operating practice with combined blast. A complex dimensionless parameter, which re- flects the properties of the interacting media, is the ratio of the kinetic energy of the hot, com- bined gas stream to the potential energy of the coke flow, burning at the tuyere in a gas of known composition. Statistical processing of experimental data on the extent of the raceway zone, obtained from literature and our own work on operational furnac- es, has led to a working formula of the following Form:

Jan 1, 1981

Exposure to respirable contaminants in mine atmospheres has long posed a serious hazard to miners. The control of these hazards, some of which can have sudden and catastrophic effects and some others, slow and long enduring consequences, has been a major concern for labor, management and government alike. This concern has manifested itself in four primary mechanisms of control -- (1) regulatory control through minimum standard setting by the passage of mine health and safety laws, (2) engineering control through design and operation of mines according to the best recommended practices, (3) medical control through periodic physical examinations, wearing personal protection devices, etc., and (4) legal and social control through workmen's compensation laws for occupation related health rleterinratinn_

Jan 1, 1988

By S S. Kanchibotla, S Morrell

In recent years there has been a growing recognition of the impact that mining practices have on the efficiency of mineral processing operations. Head grade, dilution, particle size distribution and their variability are known to have a significant effect on the throughput and recovery achieved in mineral processing plants. Improved process monitoring and modelling have provided the opportunity to identify and quantify some of these impacts and to define very significant incentives to optimise the overall operation from the mining face through subsequent comminution and processing. The Julius Kruttschnitt Mineral Research Centre has been undertaking research to optimise æMine to MillÆ performance through a major AMIRA research project and through individual research contracts with mining companies. This work has resulted in a broad range of field and laboratory experience in terms of both the challenges and the opportunities encountered when tailoring blasting operations to suit the overall æMine to MillÆ production chain. This paper describes the objectives of æMine to MillÆ blasting to optimise the system of rock breakage involved in the blasting, crushing and SAG milling of hard, brittle ores. The design of such blasts falls outside the conventional envelope of experience for most engineers and requires the consideration of some critical factors if the objectives of such blast are to be met and some of the potential problems are to be avoided. Experience to-date has also found that the quality of implementation is critical to the success of æMine to MillÆ blasts.

Jan 1, 1999

The intention of this paper is to examine the practical and technical aspects associated with the measurement of blasting related phenomena. The emphasis is directed towards the acquisition of quantitative data rather than its theoretical interpretation. The application of advanced technologies will require that many more people involved with blasting become familiar with this topic. Against the many other disciplines where measurement may be beneficial, blasting is peculiar on several counts. 1) It must almost always be carried out in the field, and very often in a production environment. 2) Much consideration must be given for the safety of personnel and equipment. 3) The process is dynamic and seldom repeatable. Because the blast process is so dynamic there is little opportunity for direct examination. For this reason measurements are almost universally made using electronic techniques. In this way the event can be captured faithfully as it occurs and later examined in detail, after the fact. It is obvious that some familiarity with these electronic techniques is a necessary ingredient for successful blast monitoring.

Jan 1, 1990

As a result of cheap Maui gas and plentiful hydro-electricity, over the past few decades New Zealand has enjoyed some of the cheapest energy of any OECD country. The situation is changing; at best we are facing some radical changes in energy use, at worst we are facing a crisis resulting from the following:   Cause 1: Maui gas will be exhausted by 2012. Distorted pricing and supply contracts; resulted in Huntly Power Station, a coal mine mouth generator running on 70 per cent Maui gas until very recently!   Cause 2: Investment in new generating capacity (and transmission) is woefully inadequate; as a result hydro lake levels are being continually pushed to the limits.   Cause 3: Distorted thinking is everywhere, for example; æWe will find more cheap gasÆ. æGas is clean û coal is dirtyÆ. Hot air  û ægreen alternatives such as wind generation will save usÆ. æNo NuclearÆ. The outcomes of the distorted thinking will be price increases, then shortages (there is nothing like "black-outs" to focus national thinking) and finally recession.   But what can NZ do? - Mine Coal. Coal jump-started the industrial revolution, it can provide the transition to post-gas and oil. NZ has the second highest reserves of coal per capita in the world, yet we use less that any other country with significant coal reserves. Our exports of our best coal have increased threefold, yet out own consumption has remained static at about 1-1.5 Mtpa for the last 30 years. Our coal is NZ owned and inexpensive relative to other energy sources, even allowing for infrastructure and environmental costs.   What can we do? We as mining professionals can promote informed responsible development and investment in the country's mining and energy business. We can galvanise public opinion on issues such as æunbundlingÆ our entire energy chain from mine-to generator-through transmission, even if the nuclear issue has to wait! With oil above US$70/bbl substitution is feasible. For individuals, there is always solar!

Jan 1, 2006

By Rowley M, Bradford P

Plutonic Resources Limited (formerly known as Pioneer Mineral Exploration Limited) delineated, developed and operates the Plutonic Gold Mine located 180 kms northeast of Meekatharra, Western Australia. Gold mineralisation was discovered in the Marymia greenstone belt by Great Central Mines NL (GCM) in 1988. There was no previous, recorded gold mining activity in the area. In May 1989, Plutonic Resources Limited (PRL) entered into an agreement to acquire a 51 per cent interest in the three Mining Leases containing the Plutonic deposit from GCM. Subsequently in December 1989, PRL acquired the remaining 49 per cent interest in the Mining Leases. PRL and GCM are also involved in a 51:49 regional joint venture on extensive Exploration Licences in the vicinity of the Mining Leases. Following due diligence validation, reserve delineation and testwork, a feasibility study was undertaken in conjunction with JR Engineering Services, which led to the financing and development of the project for operation in August 1990.

Jan 1, 1991

Many types of micro-organisms inhabit iron ore deposits contributing to biogenic formation and conversion of iron oxides and associated minerals. Bacteria such as Paenibacillus polymyxa are capable of significantly altering the surface chemical behaviour of iron ore minerals such as haematite, alumina, calcite and silica. Differing mineral surface affinities of bacterial cells and metabolic products such as proteins and polysaccharides can be utilised to induce their flotation or flocculation. Mineral-specific bioreagents such as proteins are generated when bacteria are grown in the presence of haematite, alumina, calcite and silica. Alumina-grown bacterial cells and proteins separated from such cells were found to be capable of separating alumina from haematite. Biodegradation of iron ore flotation collectors such as amines and oleates can be effectively utilised to achieve environmental control in iron ore processing mills.

Jan 1, 2009

P.IISTRACTThe Pacific Rim is advantaged by the uniqueness and diversity of its geological features. Why then is geology given so little regard in the education systems of the countries of this region? Not that these countries differ greatly from those in other parts of the world. Papers presented during the Precollege Geoscience Education session at the 28th International Geological Congress (28th IGC) held in Washington, July, 1989, indicated strongly that the problem is universal. There is a marked decline in interest in the Earth sciences and many nations are looking towards methods that might change this trend. Problems affecting geological education include the lack of purpose and direction, its obsolete curricula and the difficulty in attracting gifted students.The world-wide plight of geology comes at the very time when it should be fundamental to a public understanding of the global effect of human population pressure. There is a universal awareness of "the environment" but very little awareness of the science that has supplied most of the data. Geology, as the science of the Earth, is of paramount importance to an understanding of our life on this planet, particularly in its role as the source of our every need.

Jan 1, 1990

By Yianatos J. B

The advances in the study of control alternatives for flotation columns are reviewed. An integral solution to the control problem has to deal with problems associated with instrumentation, process modelling, control strategies and control algorithms. The term hierarchical control is used here to mean the intelligent integration of available knowledge, control algorithms and logic rules of decision. The selection of information, algorithms and rules is based on the experimental and theoretical knowledge of the column flotation process. The software support was designed and implemented in object oriented computer programs. This technique allowed the implementation of a combination of control techniques, algorithmics and heuristics, in the form of a control strategy. This strategy has shown to fit well with processes exhibiting complex dynamic characteristics. The hierarchical control was implemented in a pilot column and included the following general aspects: co-ordination of distributed conventional control loops, use of sets of control parameters for the froth depth control loop according to the froth depth state, verification and diagnosis of sensors, on-line predictive estimation of gas hold-up, diagnosis of common operating problems and the use of predictive control to account for feed flowrate changes.

Jan 1, 1995

The Australian bulk explosives industry has matured significantly over the last five years and it would appear that the rest of the world is following suit. This maturity is characterised by the technical sophistication of modem bulk explosives, an increase in the technical competence of the explosives consumer and a greater openness in the debate on the quality and performance of explosives. The principal mechanism by which these advances have been made is undoubtedly commercial competition in the market place although a new element, technical competition between manufacturers and independent professionals, has and will continue to play an important role in the development of the industry. The relationship between the explosives manufacturer and consumer is necessarily both complementary and competitive. This paper identifies the need for the consumer to take a more prominent role in the critical analysis of the performance of explosives and to use his commercial influence to direct explosives manufacturers at least in the direction required for the future technical development of the industry.

Jan 1, 1990

Maximising margins in today's competitive international commodity markets demands superior productivity. This requires more than selecting the best equipment. It requires continually improving the efficiency of production, commercial, marketing and administrative processes under the control of solid modern management systems.This paper introduces an integrated way of working that includes proven management systems for successfully changing work practices and attitudes, developing managers and increasing accountability. It introduces a proven methodology for systematically involving people in sustained true continuous improvement of processes for maximising productivity, safety and revenue while minimising costs.

Jan 1, 1998

This paper discusses why Argyle Diamonds adopted thickened tailings disposal in 1985 and how the system was developed over the next seven years. A wide ranging review of the thickened tailings disposal system and the tailings deposit it was producing was carried out during 1992 and 1993. The results of that review led to the abandonment of thickened tailings disposal at Argyle because of serious concerns about the stability of the resultant tailings deposit. The exposure to the risk of liquefaction and an assessment of the consequences if this happened to the thickened tailings deposit are shown. The criteria for selecting the new tailings disposal strategy are then described. The final section of the paper discusses the management strategies that have been put in place. These are designed to: ò reduce the risk posed by the thickened tailings deposit to an acceptable level; ò safely store tailings to the end of mine life; ò produce a land form that can be decommissioned to the satisfaction of Government regulatory bodies.

Jan 1, 1996

Exploration requires substantial capital, and is an extremely risky business (only 1 in 100 prospects ever becomes a mine). The average lead time, that is the time between discovery and production, varies from around two years for a gold mine, to 15 years for a lead/zinc mine. Since it takes years to find, prove and develop most ore bodies, exploration must be carried out years ahead of the depletion of existing deposits. Investors in exploration are exposed to risk for long periods before knowing whether they will receive a return on the funds invested. The risk, high-cost, uncertainty and long lead times involved in exploration make it an aspect of commerce that most managers and investors find difficult to rationalise or understand. Nevertheless, it is a given that the long-term survival of the mining sector depends on discovery of new mineral deposits, however the immediacy of the need to find or acquire new mineral deposits in order to compete and prosper in the industry is less well understood. This paper examines the commercial realities which underlie exploration for new mineral deposits. The first and foremost reason for exploration is to maintain or increase depleting ore reserves which are the asset base of mining, but there are other compelling commercial reasons for exploring, and these are: to maintain return on investment, to achieve growth or create wealth through discoveries which lead tonew mining ventures, to remain competitive in the industry, to diversify, and to control raw material source for mineral processing and/ormarketing ventures. Exploration is necessary for survival of the industry, and also for survival of organisations competing in the industry. The organisations which discover the best orebodies are in the best position to compete, and mining organisations which fail to find or acquire new mineral deposits rapidly become uncompetitive and unable to maintain return on shareholdersÆ investment.

Jan 1, 1998

Experience in evaluating grade control at operating mines has shown that a number of similar errors re-occur in diverse settings. These can be broadly classed as technical errors, and procedural or grade contra management errors. Examples of typical errors are presented a; generalised case studies. A brief explanation of why the recommender solution worked is also presented for each case.

Jan 1, 1993

By M Scoble, E Rubio

The re-engineering of manufacturing production systems has demonstrated the benefits from using production information for optimising processes. This paper explores the techniques and issues in the acquisition and analysis of mine production data for tactical decision making in production control. The use of information and operations management tools is presented in the context of block caving studies, with particular focus on the relationship between secondary breaking and LHD production performance.

Jan 1, 2000

Process engineering principles are used to analyse the features of leaching processes for large masses of low grade, unprocessed ore. Different performance characteristics are related to the numerous variants of these processes. The variant for which reagent enters a heap only via the input solution is further subdivided into three modes of operation. The three modes may occur in testwork and full-scale operations; the effects of process variables on the rate of the process are completely different in each mode. The mode can be identified by the time at which reagent first appears in the pregnant solution. It is related to the ratio of the height of the heap and the thickness of a band of ore in which the reactions are localised. Synthesis of the phenomena occurring within a heap via a computer program has produced a quantitative relation for the reaction band thickness. The program has been validated for several different systems. The overall achievement is that the mode of operation and the rate of the process can be forecast before column testwork is commenced. Some applications of the outcomes to testwork, process design and operational tactics are described.

Jan 1, 1994

By B Mil, D P. Adhikary, M S. Craig, P Rutzou

As shallow coal reserves with easier mining conditions are exhausted, future deep coal mining with difficult mining conditions may face significant economic, technical and environmental challenges. Moreover, due to increased coal production capacity with the new generation longwall systems, predicting adverse mining conditions has become more important than ever before. The potential impact of these difficult conditions is an increase in mining risks and costs. Reliable prediction of rock mass deformation, mine stability and mine water inflow is not only essential for improving mine safety and reduction of coal production costs, but it is also important for the assessment and management of the environmental impact of mining. This paper briefly describes an integrated approach to mine groundwater simulation and prediction. Central to this integrated approach is a three-dimensional computer code called COSFLOW, developed by CSIRO of Australia in collaboration with NEDO and JCOAL of Japan to address the pressing issues of mine water management. COSFLOW incorporates unique features that make it ideal for the simulation of coal mining and examining the interaction between rock fracture, aquifer interference and water flow. This paper also presents an example of an application of the integrated approach and COSFLOW in water inflow prediction at Springvale Mine in New South Wales.

Jan 1, 2006

By A McEwan, J Masters, C A. Jackson, A Catanzano, V Sharp, M Millen, S Rainey, S J. Spencer, G Roberts

A passive acoustic emission (AE) monitoring system has been developed and trialled on two M10000 IsaMillsTM. The analyser detects AE stress waves generated by grinding media impacts with the mill liner during mill operation. Locally propagating stress waves can be detected on the exterior liner surface using strategically mounted broadband accelerometers.The analyser has been developed into a robust commercial prototype system, and has been designed, installed and commissioned with Xstrata Technology at two mineral processing plants.A six-month field trial showed large-scale variation in AE power signature with process conditions. Analysis of the enveloped AE power output demonstrated a strong correlation with mill process conditions – more specifically grinding media relative loading, feed pulp density, feed volumetric flow rate and feed type.Placement of accelerometers along the length of the mill body provided key information on the grinding media relative deportment. The enveloped AE power detected by the mill body, discharge pipe and bearing housing sensors all captured information strongly correlated with mill operating parameters and process state.The prototype analyser demonstrates suitability as a long-term online tool for stirred mill performance monitoring, and potentially for optimisation and control, in beneficiation plants.CITATION:Jackson, C A, Spencer, S J, Masters, J, Sharp, V, McEwan, A, Rainey, S, Catanzano, A, Roberts, G and Millen, M, 2014. Monitoring of M10000 IsaMill™ process performance by passive acoustic emissions, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 241–254 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014