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By M Neurohr, B Wacker, D Mensing, C Murphy, W Kitz

Mining operations have large power requirements. The biggest consumers of energy are the drives for the mills located in the concentrators. Assuming that the decision is made on how many mills are needed and how big these mills will be, it can be determined how these mills should be driven. The decision as to which drive should be applied depends on design limits for different mechanical or electrical drives, anticipated operation modes, capital expenditure optimisation and lifecycle cost optimisation.The task for the engineer specifying the drive equipment is to select a drive solution that can debottleneck the operation, avoid interruption of production and enhance the reliability of the process. At the same time, the engineer must choose a design that enables cost optimisation either in a single investment or in relation to the total cost of ownership (TCO).This paper outlines different mechatronic or electric drive alternatives for tube or horizontal mills applied in the mining industry, along with their advantages and disadvantages. The paper covers a wide range of applicable drive systems and provides a background to the benefit of applying integrated drive systems.CITATION:Wacker, B, Kitz, W, Murphy, C, Neurohr, M and Mensing, D, 2015. Application of different drive systems for horizontal mills, in Proceedings Iron Ore 2015, pp 205–216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By P Vix

A thermodynamic model of the copper Peirce-Smith (P-S) converter has been developed to predict the behaviour of magnetite in the converter slag, the amounts of slag and matte, the compositions of slag and matte, the volume of the bath, the bath temperature and the SEMTECH OPC signals. The predictions of bath temperature, slag and matte compositions and magnetite content in the slag have been validated by the industrial data. The effects of fluxing strategy, returns and skim charges, oxygen enrichment and temperature on the magnetite formation in the slag have been predicted and discussed. Some industrial applications of this model have been presented.

Jan 1, 2005

Various aspects of the history of mining at The Zinc Corporation, Limited (ZC) and New Broken Hill Consolidated Limited (NHHC) are examined. There are some discussions about the various methods used to mine the pillars left after the primary mining operations, with an enphasis being placed on the more modern pillar mining methods. Some new pillar mining proposals are presented. INTRODUCTION In the past, pillar reserves at ZC/NBHC have been scheduled for mining by labour intensive and high unit cost mining methods. These methods include both undercut and fill and overhand square set timber stoping. Recent technological advances in large diameter longhole drilling and high charge density explosives have culminated in the mechanised Vertical Crater Retreat (VCR) mining method and this method has been successfully used for the extraction of two pillars at NBHC and more stopes are planned. However the use of VCR methods for mining pillars at ZC/NBHC is restricted to approximately 50 per cent of the total pillar reserves and it appears that high cost methods will be needed to mine the remaining Pillars.

Jan 1, 1983

By F Baars, M Zu, C A. RosiFre, L Lobato

A genetic model for the genesis of high-grade (>65 wt per cent Fe) Proterozoic, banded iron formation (BIF)-related iron deposits such as the Tom Price, Mount Whaleback deposits in the Hamersley Province (Australia), the N4E, N4W, N5 deposits at Carajßs (Brazil), the Aguas Claras, Conceitpo, and Casa de Pedra deposits in the Iron Quadrangle (Brazil), the Donkerpoort West, Kwagas East deposit in the Thabazimbi iron ore district (South Africa), or the Saksagan ore field at Krivoy Rog (Ukraine), needs to take into account the: timing of regional metamorphism with respect to the upgrade of BIF to high-grade iron ore; significance and relationship of the proto-ore to the hydrothermal alteration minerals and zonation and the process of iron enrichment; source and oxidation state of the hydrothermal fluids that caused the iron enrichment; types of geochemical processes that caused the hydrothermal alteration and iron enrichment; and significance of the widespread carbonatisation of the host rocks as a prerequisite for high-grade BIF-related iron mineralisation.We argue that a unifying model for high-grade BIF-related iron deposits cannot, presently, adequately explain the geological and geochemical characteristics observed in these deposits and, therefore, provide two end-member models that take into account the diversity of geological and geochemical ore deposit features. Our discrete model for the genesis of high-grade, BIF-related iron deposits is based on the interpreted tectonic setting, distinct hydrothermal fluid source of, and processes observed in, major BIF-related iron deposits. We divide two end-members: Proterozoic deep fault-magmatic (Carajßs) type, and Proterozoic rift-basin (Hamersley) type.Both end-members experienced varying degrees of deep weathering episodes that effected the hypogene enrichment and, ultimately, yielded the high-grade iron ore mined in many places today.

Jan 1, 2005

The society in which we live is one of change, and we professionals are part of that society. The importance of this simple and obvious statement is often overlooked. My Presidential Address examines the question: can professionalism survive in our changing society?There is ample evidence to show that our society is changing, and that the rate of change is exponential. This rapid and accelerating rate of change is what Alvin Tomer refers to as "future shock". Rapid change means that we do not have time to become accustomed to what is happening around us and to feel comfortable with it; the greater the rate of change the greater the discomfort. The effect that this has on people is varied; the change may be either expected or totally unexpected.The rate and extent of change in society is not the same for all countries nor for all industries or occupations. Change is more rapid in Japan, Korea or Taiwan, than in Australia. It is more rapid in our cities than in the bush, more rapid for professional businessmen than for farmers. In our minerals and petroleum industries, we are still adjusting to the great changes that have taken place over the last fifteen years. In the past, products from our industries were sold on a free and open market. Today, mineral development and production in most undeveloped countries and some developed countries is manipulated for political, social and economic reasons. Changes of this nature have had a devastating effect on the operations of established mineral producers in the democracies.Because of the accelerating nature of change, we must recognise that the past is not a reliable guide to the future.Although extrapolation of the past into the future is a basic ingredient of commercial survival, extrapolation is less and less reliable.I borrow from others in quoting the Irish proverb: "The future is not what it was".The future is where our business lies and most of us at this Conference must endeavour to understand it and adjust to it. I believe in the old adage that:You can't know where you're going if you don't know where you've been and where you are at.There are a number of major factors which have created change within our social, economic, and industrial environment in recent years.

Jan 1, 1985

By R Hargreaves, C Morley

The authors often see problems on mine sites that are due to insufficient feedback between technical discipline silos as the realities on the ground fail to inform the models and plans used to drive resource exploitation. Resource modelling, reserve definition, life-of-mine planning, short-term mine planning and scheduling, mine operations and beneficiation operations are all processes that inform each other, but in many instances feedback between these processes occurs in an ad hoc way and only after problems have come to light.Universal reconciliation uses a multidisciplinary approach across the entire mining value chain to identify both opportunity and loss of value and to maximise operational performance. This paper will look at the operational effectiveness of universal reconciliation and will outline the important elements that make it successful, including how to map out the detail underpinning modelling, planning and execution processes. We do this by documenting the physical processes, logical work practices, organisational roles and responsibilities, data origin and quality, working assumptions and information management practices at an operation. The results quickly show how misinformation and assumption causes suboptimal decisions to be taken, where inefficiencies exist and what the opportunity is to remedy these issues.A universal reconciliation study opens up an opportunity for stakeholders to reassess how the operation should be run and how operational effectiveness should be measured. Clear envelopes for reconciliation become obvious and questions about the practicality and data quality can be addressed.A reconciliation code of practice is a key element of a successful universal reconciliation project and the authors outline the important aspects that will provide an operating model, showing the effectiveness of the resource and reserve modelling, the practicality of the mine planning and scheduling practices, how well the mine operations team are executing these schedules and how effective the processing area is given what it is fed. Most importantly, a system that allows operations time to react before the losses become systemic and that is based on identifying early warnings from hard data when these processes start to wobble is outlined. Finally as a case study, the revenue and cost benefits resulting from universal reconciliation diagnostic projects for nine mine sites is documented.CITATION:Hargreaves, R and Morley, C, 2014. Universal reconciliation – a multidisciplinary approach across the entire mining value chain to identify loss of value and maximise operational performance, in Proceedings Ninth International Mining Geology Conference 2014 , pp 411–420 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By S Thacker, M Noakes

The Newmont Tanami Operations (NTO), formerly the Granites Gold Mine, commenced operation in the mid-1980s with tailings deposition evolving over the past three decades as production has increased and the operation has expanded. Paddock-style tailings storage facilities (TSFs) and in-pit tailings deposition have fulfilled the tailings requirements for NTO over its lifetime with the technical specifications of these facilities improving over time in line with the positive development of standards, guidelines and best practice.This paper reviews the options for tailings storage facilities at NTO and the many considerations that have been analysed and deliberated upon before settling on specific TSF types and designs. It also explains the operating philosophies of the tailings deposition and how the facilities have always strongly maintained the optimum capture and retrieval of water. The current TSF design and criteria is presented, along with the introduction of dry tails harvesting for use in paste production as a backfill product for the underground mine. Tailings deposition and recovery remains a critical function of the Granites process to ensure long-term operation and gold production.CITATION:Thacker, S and Noakes, M, 2015. Newmont Tanami Operations – tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 305–314 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Holliday RJ

The Imperial Smelting Furnace (ISF) was developed in Britain during the 1950's as a process which could produce zinc from a blast furnace. Since then it has evolved into an efficient means of producing zinc and lead from lower grade raw materials, both of primary and secondary origin. These changes have been in response to the need to improve the cost competitive position of the ISF in a climate of decreasing metal prices. The improvements at the Cockle Creek smelter of Sulphide Corporation Pty Limited have resulted from work undertaken in four main areas: 1. Changes in plant design and operating practice to give more stable furnace operation. 2. Improvements to the quality of sinter being charged to the furnace. 3. Improved monitoring of process variables and the formulation of control strategies based on the improved data. 4. Increased understanding of the processes occuring within the furnace shaft to allow predictive modelling to be undertaken. Work in these areas is still progressing but the work to date has resulted in a significant improvement in the production rate and efficiency of operation.

Jan 1, 1984

By J Battista, J Grace, I Brunton

The need to better understand and develop strategies to improve instantaneous shovel productivity at the Cadia Hill Open Pit Mine (CHM) instigated the development of the æShot to ShovelÆ project. This project has involved the implementation of a drill and blast (D&B) information management system to capture current and future experience. Equally important has been the manual monitoring of shovel productivity and direct use and analysis of high precision GPS and productivity data logged by ModularÆs Dispatch System. The analysis of this type of data was facilitated with the application of GIS based software (ie MapInfo). This has shown to be a powerful medium to display, interpret and assess this type of spatial information on a blast-by-blast basis. Cadia HillÆs well-defined D&B processes supplemented with the application of the above systems are providing a unique capability to assess and better understand the impact of both muckpile conditions and operator proficiency on instantaneous loading productivity. This is facilitating the definition of appropriate optimisation strategies in both drilling and blasting and operator proficiency training. This paper gives a summary of the work conducted in the æShot to ShovelÆ project, describes the engineering tools being implemented and discusses preliminary findings and their practical implications.

Jan 1, 2004

The application of cheap robust microprocessor based units to achieve monitoring and control in an underground mining environment is described. The functional layout of the programmable controller and the methods of multiplexing and processing information from local and remote sources are examined as are features for refrigeration plant control.High noise immunity communication to a remote micro computer uses existing telephone lines and enables display and print of essential data. The development of this system then leads to applications in monitoring compressed air, ore transport and underground fires.In conclusion, the problems of data presentation to different levels of management and the future philosophy of a central multi-reporting system are discussed.

Jan 1, 1985

The need to schedule ore production to make maximum use of the strength gained by cem- ented fill during curing is discussed, to show how cement content and hence fill cost can be kept down for any particular operation. Results from laboratory testwork on Isa Mine fill conducted by the author while employed by Mount Isa Mines Limited form the basis of the Discussion

Jan 1, 1973

This paper compares and evaluates the impact of income tax and value-added tax on the decision to explore for minerals or to develop a mine in four countries: Australia, Papua New Guinea, Argentina and Indonesia. Three aspects are considered in depth:- domestic tax rules applicable to mining projects;- taxation of foreign mining investment and foreign providers of expertise;- taxation of project finance (other than equity) from foreign sources.Specific tax issues discussed include tax deductibility of various costs, treatment of tax losses, special tax incentives, comparative treatment of various corporate structures, non-resident withholding taxes, and tax costs of various forms of project finance. The paper also illustrates the comparative impact of income tax on rates of return by means of a simulation of a mining project in each of the four countries. The simulation demonstrates why the highest rate of return may be obtained in Argentina and the lowest in Australia.Relevant features of the income tax systems in each country (at 15 February 1990) are summarized and compared in several tables annexed to the naner.

Jan 1, 1990

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

The paper presents two methods for periodical identification of the dependence between haulage speed and loading torque of the shearer for periodical corrections of control algorithms. These algorithms are useful for working with small microprocessor-based systems. The paper is concluded with results of identification using above methodsand with discussion about their merits and demerits. The longwall mining system is the basic exploita-tion system used in coal mining in Poland. The quantity of coal produced by this system, using a shearer loader as a cutter-loader machine is esti-mated at 170 million tones per year. For this rea-son scientific research concerning these machines is of major practical significance.

Jan 1, 1985

By J P. Sykes, T C. McCuaig, J E. Vann

Resources added to the global metal inventory through exploration over the past 15 years have been generally of poor quality (declining grades, recoveries and lack of acceptable financial return). Similarly, companies opting for an acquisitions-based strategy have had to pick from a group of poorer quality resources left from previous exploration booms, and will struggle to deliver this metal to market economically. Increasing difficulty in obtaining sufficient social and community acceptance of mining projects and potentially an energy-constrained future may exacerbate this problem, redefining what is considered ‘ore’. There will need to be more focus on deposit quality, defined as sustainable margin in the future business environment.Traditionally there has been a lack of translation of ‘mineralisation quality’ back to mineral project design and mineral exploration. This disconnect is due to two main factors: the first is technical – inherent deposit variability; and the second is organisational and socio-psychological –the mindset of explorers and project managers themselves.There are four elements to value realisation for a mineral deposit: (1) social licence to operate; (2) geological factors (depth, geometry, water and geotechnical, and geometallurgy – influenced by texture, mineralogy, chemistry and grades); (3) financial engineering (capex, opex, future commodity prices, future energy prices), and (4) operating factors (production rate, recovery, energy consumption). These elements are strongly interdependent, and geology underpins and drives linkages between them. A quality deposit addresses all of these elements and thus can be developed in a time frame that allows acceptable returns to the owners of the invested capital.Geological drivers of the above elements can be measured and mapped throughout a deposit. Moreover, when viewed in the context of mineral systems, a predictive understanding of the common causative processes of quality (despite deposit-scale variability) is emerging, and with it the ability to target quality of mineralisation, not just quantity of mineralisation.The second factor is a ‘heuristic software problem’. Current lines of education (and consequently organisational and professional structures) are discipline-based, producing ‘silos’ that do not speak each other’s language and work with different ‘mental models’. People who effectively recognise systemic links between these silos are called ‘boundary spanners’, of which we propose two distinct types: outside-insiders and inside-outsiders. Outside-insiders are people who are within a community, but recognise advances in outside fields and effectively integrate them into the community. Inside-outsiders start outside of a community, and successfully bring new ideas into it. Common traits in boundary spanners are: they seek exposure to (and embrace) key ideas that are outside of the framework of their own specialisation; they have high mental processing ability (MPA) – the ability to connect systems that are currently not perceived to be connected; and they introduce ideas from outside a field into a new context in a way that re-frames the field.The challenge is to identify and nurture potential boundary spanners that can build critical links, in particular between the (largely geoscientific) mineral exploration mindset and the (largely non-geoscientific) project development mindset. Critical linkages to be built are between mineral system science, targeting science, and whole of value chain modelling.CITATION:McCuaig, T C, Vann, J E and Sykes, J P, 2014. Mines versus mineralisation – deposit quality, mineral exploration strategy and the role of ‘boundary spanners’, in Proceedings Ninth International Mining Geology Conference 2014 , pp 33–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

A system of decline mine entries and ore haulages has been designed for the Mt. Windarra mine. This choice was controlled by the nature of the ore- bodies, the mining method chosen and the capital cost of development re- quired for production. Mine entries are being driven 4 metres high and 5.5 metres wide and decline at 11%, to accommodate diesel haulage vehicles of 35 tonnes capacity. The.Mount Windarra haulage system and the design parameters used in its selection and design are discussed, and general design and selection parameters are proposed.

Jan 1, 1973

By Liu H, Chen S

Natroalunite is one of colouring minerals in kaolin. In this investigation, natroalunite, on which Ca(II) was adsorbed, was flocculated by HPAM and kaolin was depressed in suspension. The adsorption of Ca(II) on the natroalunite surface was studied by zeta-potential measurement and Auger Electron Spectroscopy analysis. Ca(II) was adsorbed more on the natroalunite surface than on the kaolin surface. The mechanism of Ca(II) adsorption was considered to be chemical adsorption on natroalunite and to be physical adsorption on kaolin. It has been found that Na6P6O18 and Na2Si04 can strongly affect Ca(II) adsorption on the surface of kaolin, but weakly on the surface of natroalunite. The effects of degree of hydrolysis and the molecular weight of HPAM, the effect of pH and the effect of Ca(II) have been studied. The kaolin ore, containing SO3 1.05 per cent has been processed with this method. The products only containing S03 0.36 per cent and the weight ratio of concentrate 52.27 per cent were Obtained.

Jan 1, 1993

By E Niva

The IsaMillÖ is challenging the way that plants are designed and operated. This paper challenges existing designs of concentrator flow sheets, particularly focusing on magnetite circuits.   From what has started out as a small scale ultra fine grinding mill in the pharmaceutical and pigment industries, it has been redesigned and improved upon for mineral processing, and has been the mainstay of fine grinding applications for over ten years. These applications have required energy efficient grinding to succeed, and have been predominately in the base metals industry.   Further development of the IsaMillÖ has now resulted in the machines being able to treat larger tonnages, with higher capacity motors. This development, along with the introduction of purpose designed ceramic media, has allowed the mill to treat courser feed sizes. At the same time, the mill still offers highly efficient grinding, and has enabled it to be operated in coarser tertiary and secondary grinding applications.   The acceptance of the mill in coarser applications, predominately in base metals and PGM applications, has enabled the IsaMillÖ to be a serious contender for beneficiation in other minerals. One such application is the potential for IsaMillsÖ to be part of magnetite flow sheets, which are being considered in Australia to meet the growing iron demand of China. The high energy efficiency of the IsaMillÖ compared to conventional technologies, as well as the smaller infrastructure requirements, provides a great opportunity to reduce the power intensity of magnetite circuits.   This paper will examine the use of IsaMillÖ technology in conventional grinding applications, including recent testwork in a primary grinding base metal circuit, as well as testwork on magnetite ore comparing a lab scale IsaMillÖ with a lab scale Tower Mill.   The growing demand for minerals over the next decade, coupled with higher energy cost, will result in energy efficient technology, such as the IsaMillÖ, being included in standard circuit design.

Jan 1, 2008

Process control computers are finding ever increasing applications within the chemi-cal and mineral processing industries.To purchase a system which fulfils both the immediate and future needs of operating, technical and management groups, requires an appreciation of the capabilities of the system software and the constraints which apply to user development of application software. Early decisions are then required as to who will develop and maintain the software. Rules and conventions must be determined and adhered to if the end result is to be an orderly, well structured and properly documented system. Software development and maintenance represents a substantial, and often hidden, cost. Getting it right the first time will avoid either a major re-work, or having to live with a system which is extremely diffi-cult (at the worst, impossible) to trouble-shoot or modify.

Jan 1, 1985

By M Campbell, A Jeffcoate, J-C Vannay, B Perriaux

Phyllite waste rock at the Simandou Pic de Fon and Oueleba Iron Ore deposits (Guinea, West Africa) variably weather to form clay-rich rocks. This weathering modifies the mineralogical, geochemical and mechanical properties of the phyllites. Final pit walls will largely be formed in phyllite, so it is critical that the slope design takes account of the distribution and variability of weathering within this material. Phyllite intact material strength has been correlated with geochemistry (ie mineralogy) facilitating the establishment of domains of intact rock strength (IRS). In order to calibrate this geochemically-based strength model, core from diamond drilling (DD), comprising a variety of phyllite material types (from soft clay to moderate strength rock), was geotechnically logged to assess intact strength; further validation was achieved by uniaxial compression (UCS) testing and point load tests (PLT). The correlation between geochemistry and strength offers a potentially powerful tool for differentiating basic mechanical properties of the rock mass, especially at Simandou where a significant proportion of the resource drilling is done by reverse circulation (RC). Unlike DD, reliable measurements of material strength from RC samples can prove difficult, especially in clay-rich material. Therefore, gaining information from routine geochemical assay results, independent of the sampleÆs physical integrity, is a valuable and cost-effective source of reliable empirical data. Data acquired using this approach provides an opportunity to develop strength domains, which are integrated into mine planning block models. In combination with other geotechnical characteristics, this can be a valuable input to the development of geotechnical models. This technique has allowed spatially representative rock strength data to be derived and offers the potential for optimising pit slope angles in areas where hitherto conservative design criteria had been assumed.CITATION:Jeffcoate, A, Campbell, M, Vannay, J-C and Perriaux, B, 2013. Modelling intact rock strength of clay-rich rocks with geochemistry at the Simandou iron ore deposit, Guinea, West Africa, in Proceedings Iron Ore 2013 , pp 193-202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013