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By A R. Bye

The mining industry is facing some key challenges that provide a compelling case for geometallurgy initiatives. Over the last 30 years, the average grade of Australian orebodies being mined has halved while the waste removed to access the minerals has more than doubled. In the last eight years, the industry’s energy consumption has increased 70 per cent while multi-factored productivity has fallen 24 per cent. The paper documents a broad range of industry case studies which demonstrate strategies for gaining value from geometallurgy.The mining industry constantly faces the key questions of how significant ore variability is on mine valuation and how would knowledge of the variability change the mining schedule, mine to mill design and operation. Using case studies the paper describes the methods used for incorporating mineral extraction attributes into orebody models and their technical integration into daily operation as well as mine planning optimisation. While pit optimisation from a fully attributed geometallurgical model highlights areas of opportunity and risk it is shown that during the scheduling phase of mine planning that significant value can be added. The benefits from these projects included reducing geotechnical and environmental risk, improving mine to mill performance, option analysis and quantified cash flow risk. There is growing acceptance within the minerals industry that ‘realistically assumed modifying factors’ defined by a competent person/s are not sufficient to mitigate the risk of funding mining ventures. Geometallurgy is moving away from factored ore reserves to data-rich block models providing reliable information for mining, metallurgical and environmental considerations.

Sep 5, 2011

By G Collecutt, D Proud, D Humphreys

"The hazards associated with dust explosions are well known, and coal dust explosions present a significant hazard in the underground coal mining industry worldwide. In earlier work, we presented computational fluid dynamics (CFD) simulations and test results for coal dust explosions within a 2.5 m diameter circular gallery, along with CFD simulations and test results for the suppression of these explosions with finely atomised water sprays. In this paper, we present refinements to the CFD modelling that yield a significantly improved calibration with the test results, and proceed to investigate by CFD the requirements for suppression of a coal dust explosion in a typical underground roadway. This work was carried out under an ACARP project and we gratefully acknowledge their assistance. CITATION: Proud, D, Collecutt, G and Humphreys, D, 2015. Computational fluid dynamics modelling of coal dust explosions and suppression systems, in Proceedings The Australian Mine Ventilation Conference, pp 309–314 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015

By J Whittle

This paper describes what is involved in carrying out a comprehensive optimisation of a long-term operating schedule for a mining complex. It details the data that must be assembled and discusses the different approaches to optimisation and what limitations they put on the variables and constraints that can be handled.CITATION:Whittle, J, 2014. Not for the faint-hearted, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 3–6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

Addressing community concerns in relation to an economic activity, particularly when it causes significant community impacts, is especially important for the development of extractive industry projects. Pipelines comprise an integral part of many hydrocarbon developments, which may cause different effects on local economic development, communities and the environment compared with open cast mines. This paper explores community impacts associated with a case study of the oil pipeline æEastern Siberia-Pacific OceanÆ in the Republic of Sakha (Yakutia), Russia. Based on semi-structured interviews, conducted in 2006 - 2008 in Russia, the paper investigates claims of local communities about potential impacts of the pipeline development of their environments and economic activities as well as community claims for greater involvement in sharing the benefits from this major infrastructure project. A community of Indigenous people, Evenk, is likely to be most profoundly affected by the development due to impacts on their traditional activities such as hunting and reindeer herding. The paper examines in detail the regional economic, social, environmental and Indigenous peoples concerns over the construction of the oil pipeline and investigates actions and methods adopted by community organisations to voice their concerns about the pipeline development. Finally, the paper assesses the process of interaction between the pipeline developers and regional stakeholders.

Jan 1, 2009

How often does one hear that a recent feasibility study was not a success? Alternatively, when scope of the feasibility study was sent out to tender there was a large discrepancy in tendered prices. If the tendered prices were to be compared to the consumer market, for instance the purchase of a car, where the concept is transport in a controlled and safe manner, prices vary by large factors, but then so do the specifications. In the case of a feasibility study, prices should be within a tighter margin as the tenderers are all quoting against the same concept and specification. Why do these discrepancies occur? Price discrepancies will in every likelihood be attributed to two main factors; one, the perceived amount of work and two, the ability of the bidder to carry the risk associated with the feasibility study. It is, therefore, important that the scoping of the feasibility study covers the detailed requirements as clearly as possible stating what level of accuracy is required. The feasibility study is one of the first activities in the life of a project. The study, like the project it is investigating, is subject to the constraints of time, cost and quality. Its primary objectives are to demonstrate the viability of a project within the outlined scope and constraints.

Jan 1, 1998

By R Wynn, N Stoitis, R A. Lauten, H Liang

At the Century mine in North West Queensland, MMG produces lead and zinc concentrates. The current production rate is close to 500 000 t of zinc per annum. Graphite is the main gangue in the orebody and a substantial quantity of chemicals are used to achieve an acceptable depression of graphite and other gangue materials in the current operation. In the future, it is anticipated that the content of graphite in the orebody will increase while the zinc grade will gradually drop. This scenario illustrates the importance of an optimised suite of flotation chemicals to maximise concentrate grade and recovery. As an alternative to the current reagent suite where dextrin is used to depress graphite, laboratory test work and subsequent plant trials were conducted with alternative depressants. These depressants facilitated both graphite depression and elevated zinc grades in the rougher concentrate. As an added benefit, it was also observed that the silica content in the zinc concentrate was reduced in the presence of the biopolymer selected for the plant trials. Results from both laboratory tests and plant trials will be discussed to illustrate how this change of reagent suite improved flotation yield at the MMG Century Mine.CITATION:Wynn, R, Lauten, R A, Liang, H and Stoitis, N, 2014. A change in graphite depressant to improve the recovery of zinc at MMG Century mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 179–186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

Societal influences, needs, and uses for recyclable materials are becoming increasingly important business and economic factors in the traditional natural resource companies. Several metals (such as steel, aluminium, zinc, lead and cadmium) are amenable ro recycle which eliminates solid waste generation and decreases the depletion of natural resources. In recent years, the non-ferrous industries have begun to recycle more materials and the next decade will see even larger recycle efforts. In addition to the traditonal recyclable materials, existing metallurgical plants are, or should be, able to handle and recycle materials viewed as 'hazardous'. Unfortunately, some national and regional regulations hinder, and in some cases prevent, the recycling of certain materials. Zinc Corporation of America (ZCA) is currently the largest producer of zinc metal in the USA and one of the world's largest producers of value-added zinc products. Over the last few years, ZCA has become one of the world's largest recyclers of zinc from various diverse materials. ZCA considers these recyclable materials as valuable 'land mines' that provide economic alternatives to the depletion of natural resources while serving society in the minimisation of solid waste disposal. Using the current production facilities of ZCA as a model, this paper overviews the recycling of zinc-bearing materials with special emphasis on: 1. the amenability for recycle within ZCA's pyrometallurgical and hydrometallurgical operations, 2. the quantities and economics of recycle, 3. the problems of recycling hindered by current national and regional regulations, 4. the concepts of total recycle rather than just recovering zinc while generating a modified solid waste, and 5. the motivators for recycling.

Jan 1, 1993

By C Augustin, M Hahn, K Nienhaus

Operators of mining machinery like haul trucks or excavators have very limited information about the exact distance to other equipment as well as to the natural boundaries like berms, walls and structures such as crushers. The industry is seeking solutions to provide safety and positioning. The authors have developed a solution approach which is being used in several installations. This solution consists of three parts: first robust and compact two-dimensional (2D) radar scanners that provide range and angular information of the environment especially under difficult conditions like dust, rain, snow and fog; second an intelligent data processing framework flexible enough to adopt to different machines and operation modes like speed, inclination, visibility, tire friction, GPS position, orientation and acceleration; and third a high quality and easy to use interface giving highly condensed data to the operator, not blinding the operator at night and being sunlight readable. The truth of present proximity detection sensors is that they not only have a high false alarm rate but furthermore cover only a fraction of the possible scenarios. This makes them unsuitable for stand-alone collision avoidance systems. On the other side, mine dispatch systems only deliver database and GPS information, but no information regarding the real environment. The indurad company and its Australian partner CTS (http://www.cts.com.au) addressed these aspects by developing smart productivity enhancement driver assistance tools like lane and crusher dumping assistance.An innovative driver assistance tool developed in cooperation with the coal shearer manufacturer Eickhoff and the RWTH Aachen University has been awarded with the annual research award of its customer RAG, being the largest German hard coal producer, as well as with the bauma Innovation Award in 2010.

Sep 26, 2011

By R Cannings, J Wallace, M McCamley

The mining industry continues to have major disasters (Bingham Canyon, Pike River, Upper Big Branch, Mount Polley and Samarco), which often have a devastating effect on the enterprise, in terms of personnel deaths and injuries, environmental destruction, and financial and reputational loss. These disasters are not imposed from outside the business or organisation, they are almost always a function of loss of control of the management of the organisation’s critical assets and processes that they contain or to which they are exposed.Asset integrity is discussed as an effective response to business risks in order to mitigate, control and recover from loss scenarios that could expose a mining operation to significant property damage and business interruption, or even total loss. Vital to this process is the identification and control of risks to critical assets. Components of a critical asset assurance program are presented for discussion.Formal risk assessment has a longer history in industries other than mining, eg petrochemical, nuclear, military, aviation and space industries. Risk assessment is a structured, proactive approach to understanding and improving risks, as opposed to a reactive ‘fix-it-when-it-breaks’ mentality. Risk assessment techniques were triggered by major public disasters, such as the Flixborough chemical plant disaster (1973), Three Mile Island nuclear plant event (1979) and others.Today, most industries see risk assessment as an inherent part of their business, but do mining sites capture business risks that are related to major loss scenarios, which could have a significant impact on the operation?Does your risk assessment process:- involve a team having the right skill set so that the discussion is both stimulated and technically sound?- use generic assessment when a site-specific assessment is needed?- fail to consider all possible outcomes, including maximum foreseeable loss (MFL)?- fail to identify all hazards and controls associated with a particular activity?- fail to monitor controls effectively?This paper addresses the issues identified by these questions and provides some direction for developing a risk management process where business risk associated with critical asset integrity is integrated with other business and safety and health risk processes to provide a robust method for managing your business. Case studies and common findings from critical asset failures are used to support the need to include critical asset assessments as part of business risk management processes.CITATION:Wallace, J, McCamley, M and Cannings, R, 2016. How robust are your asset integrity management processes? In Proceedings International Mine Management Conference, pp 53-64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

A mining companyÆs approach to managing the risk of theft of explosives and initiating devices should be underpinned by an organisation-wide policy developed with internal and external consultation. It should be based on the principles of sound proactive risk management, planning, monitoring and remedial action. This paper aims to provide mining (and construction)organisations with the rationale and many of the tools they need to control explosive security risks. As with all legislative compliance, they are best managed by incorporating the statutory and legal requirements into company policies, management systems and plans, operating procedures and culture. This is the approach that has been adopted in this paper. Trends we should expect: more prescriptive legislation and stricter government regulations; enhanced enforcement and more prosecution; more sophisticated detection systems, eg airports; additional compliance costs; additional vigilance on record keeping; improved risk awareness and risk communication; wider use of explosives policies, management systems and plans; and additional security staff with investigative skills.It should be noted that mining companies will be required to play their part in reducing the likelihood of explosives, intended for mining purposes, being wrongfully used to threaten, hold to ransom or to injure individuals or members of the public or to produce property damage. This will be done by putting in place safeguards to reduce the risk of theft of explosives while they are under their control. On that basis, this is a business risk assessment rather than a hazard risk assessment. A conclusion of this paper is that mining companies can and should play their part in reducing the supply of explosive materials that can then be used for illegal activities. In fact, mining companies have always had this duty, but now the stakes are higher û æcomplacency no longerÆ.

Jan 1, 2004

By W R. Adamson

Cerro Vanguardia SA (CVSA), property of AngloGold Ashanti, mines gold and silver from a system of vetiforme orebodies located in the south of the Argentine Patagonia, in the Province of Santa Cruz.Surface mining techniques are applied to develop a series of narrow pits with an average waste to ore ratio of 26:1. This quite unique constraint brings into focus the need to maximise inter-ramp and final wall angles, leading to a strong need to optimise wall control drilling and blasting in order to reduce back-break damage to an absolute minimum.The paper describes a program of applied investigation and design modification implemented during?2008?and?2009 in?two?separate pits of Cerro Vanguardia. Three distinct yet complementary damage mechanisms were identified and observed during the field components of the work; vibration induced strain fracturing, surface cratering around blasthole collars and quasi-static loading and unloading of the surrounding rock mass as a consequence of poorly controlled confinement.With these mechanisms identified, a measurement, modelling and modification campaign was conducted in order to reduce the incidence of each source of damage. Interactive design analysis and modelling, near-field vibration measurement, video capture and the application of electronic initiation technology were supported by seed wave modelling and topographic evaluation of the achieved results.Results point to the usefulness of simulation techniques for determining optimum delay timing to reduce vibration impact, while the visualisation of explosive energy distribution produced by drilling and explosive loading decisions assists in reducing the probability of over-confinement.This paper presents relevant aspects of the two fieldwork campaigns:1) describing the application of the techniques, and2) summarising the results obtained.

Nov 8, 2011

By H J. Dalstra

High-grade iron ore may be derived from banded iron formation (BIF) through four fundamentally different processes:1. syngenetic precipitation of chert free BIF,2. residual enrichment by removal of gangue minerals from BIF to form bedded (residual) ironore,3. mechanical erosion of iron oxide and chert from bedded iron ore or BIF and re-deposition andupgrading as detrital iron ore, and4. chemical removal of iron from BIF and precipitation elsewhere as a secondary (channel) irondeposit.Finally, the BIF itself may constitute iron ore if a high-grade concentrate utilised for pellets or sinters can be derived from it through mechanical (industrial) separation of iron oxide by means of crushing/milling and mineral separation.Historically, exploration for high-grade BIF hosted iron ores was focused on the residual (bedded) deposits and driven by supergene concepts. Exploration for detrital and channel type iron ores was mostly secondary to exploration for bedded deposits, but recently, a more focused exploration effort has led to the discovery of enormous moderate to low iron grade deposits in the Pilbara region of Western Australia. Exploration for high-grade iron ores using syngenetic concepts has been limited,but together with exploration using hypogene concepts offers the best hope of fi nding concealed deposits. Exploration for BIF sources suitable for concentrate ores commenced in the ‘old’ iron ore provinces after the high-grade resources were depleted and has only recently gained importance in Australian BIF provinces, mainly as a result of high iron ore prices in the last decade.

Jul 11, 2011

By D Smith

The Broken Hill deposit is located in Australia in the far western region of New South Wales. The deposit was found in 1883 and has been mined continuously since its discovery. It is considered the largest lead, zinc, silver deposit that has been discovered in the world and originally contained around 340 Mt of ore at a grade of around 12 per cent lead, ten per cent zinc and 150 g/t silver. The material remaining in the deposit represents only a fraction (perhaps ten per cent) of the original resource. Several of the world’s largest mining companies can trace their origins to the Broken Hill Field. The remaining resources on the CML7 consist of two large lower grade resource lodes that have not been subject to mining, some scattered areas of zinc lode material and the pillars and remnants of the main lead lodes.The deposit occurs in metamorphic rocks of the Broken Hill Group a division of the Willyama Super Group contained within the Curnamona Craton. The Broken Hill Group rocks have undergone multiple phases of deformation. Metamorphism is granulite grade with major shears cutting through the deposit having been retrogressed to mica schists. The deposit lies in an antiform associated with the second phase of deformation.The resultant proposed mine is situated on Consolidated Mining Lease 7 (CML 7) which occupies a strike length of 3.6 km in the central part of the 7.8 km long footprint of the orebody. Underground mining on CML7 ceased in 1975 with surface mining of silver chlorides in the weathered zone continuing until 1991. CBH Resources has been continually working to define and evaluate the remaining resource since 2002. This work has included four surface drilling programs, two underground drilling programs, an exploration decline, enormous amounts of compilation of historical data and detailed three- dimensional (3D) modelling of historical mining and the resource lodes. It is currently planned to commence production at the Rasp Mine in late 2011. The operations will produce from previously unmined lodes and from remnants and pillars.This paper primarily aims to encapsulate the processes involved from information acquisition through to resource estimation and also to highlight some of the challenges encountered and the specific techniques and practices used to overcome them. Many of the experiences at Broken Hill are applicable to all brown field sites.

Aug 22, 2011

Contractors are used extensively in the development of underground mines in Australia. Often problems arise, some originating as far back as the feasibility stage of projects, through inexperience, lack of preparation and inflexibility by both parties.Guidelines are put forward for both principals and contractors which are seen as necessary to ensure that disputation is avoided and the full benefits of the use of contractors are obtained.

Jan 1, 1985

By T Muri

The drying operation of materials from particulate solids, through slurries and suspensions, to continuous sheets represents an important part of several processes in the chemical and mineral industries. The increasing demand of high productivity at low cost and minimal environmental impact makes it complex to evaluate and choose the best available drying technology for each industrial application. The drying technologies are mainly characterised on the basis of how the wet product is related to the drying medium, namely: direct and indirect drying. In the direct drying method (convection drying), the product is brought into direct contact with the drying medium, which may be hot gas or air. Large quantities of gas are necessary for transfer of the required energy. A special case of the direct dryer is the fluid bed dryer, in which the product floats on a cushion of air or gas. The process air is supplied to the bed through a perforated distributor plate and flows through the bed of solids at a velocity sufficient to support the weight of particles. Very high heat and mass transfer values are obtained as a result of the intimate contact with the solids and the relative velocities between individual particles and the fluidising gas. In the indirect drying method (conduction or contact drying), the wet product is separated from the drying medium. The drying unit can consist of a rotor forming the indirect contact heating surface mounted in a stationary or rotating shell. The indirect method uses saturated or superheated steam resulting in low energy consumption and minimal environmental impact. In this paper, a review is given of the technologies available on the market based on different drying methods. The advantages and the disadvantages are summarised with respect to issues such as investment and operating cost, maintenance, product capacity, product handling and environmental impact.

Jan 1, 2006

IT is intended in this paper to present in broad outline to the members of the Institute a short account of the conditions and operations that constitute what is, variously known as Subterranean Warfare, Military Mining, or Tunnelling. Realizing ,the magnitude of the operations, and the varied and minute details met with in them on,the Western Front, it is the writer's intention to confine these notes to operations carried out by the First Australian Tunnelling Company. In so doing there is no wish to detract from the very fine records of the Second and Third companies it is to be hoped that members of the Institute (or others) who were with these companies will write accounts of their doings-the former in the water-logged areas to the south of Armentieres, and later in the sand-dunes at Lombardzee, and the latter in the chalk area of the Lens coal...

Jan 1, 1920

With commodities suffering dramatically low real prices, mining business margins are under intense scrutiny. Unfortunately, management systems developed early this century for manufacturing are driving counterproductive behaviours that choke productivity. The paper and presentation will explain this and present a proven methodology for increasing productivity. This will be supported by operational examples from Australian and American mining management to demonstrate the importance of modern business performance measurement and analysis systems. It will explain the importance of management systems in driving organisational change to sustain superior productivity and margins. The paper will explain why many executives and managers confuse production (a measure of volume) with productivity (which measures efficiency and effectiveness). It will explain how this and other counterproductive managerial and operator behaviours and attitudes are driven by traditional business management systems exacerbated by managerial and consulting fads. The paper will begin with the simple principle that to improve results one needs to first improve the process producing the result û and will show how this is often violated. Improving productivity then boils down to:accurately identifying opportunities using sound, modern measurement, analysis and reporting systems; methodically improving operating and commercial processes, and changing peopleÆs behaviours and attitudes to sustain changes in practices. The paper will include fundamentals of applying sound measurement and analysis to:processes directly, eg cycle time charts and their impact in cyclical (non-continuous) operations commonly used in rock breakage; drivers of productivity; and process results themselves since correct analysis identifies opportunities accurately. The paper will cover the importance of practical leadership and the need to follow a simple, solid plan for changing systems that drive behaviour. Overall, it will highlight use of modern performance Measurement, Analysis and Reporting systems to drive behaviours and improve margins - without capital investment û and make executive and managerial work easier and more effective.

Jan 1, 1999

By T Barto, D Thomson, T Norgate, C Doblin

Collaboration between CSIRO Minerals and SunSalt Pty Ltd, a salt producing company located in rural Victoria, has resulted in a commercial process to recover magnesium sulfate (commonly called Epsom salt) from the saline waters of the Murray Basin. The feed for this process is bittern; the liquor remaining after halite (common salt) has been harvested from the saline water by evaporation.SunSalt produces salt and bitterns from three locations, namely Hattah (Victoria), Mourquong (NSW) and Wakool (NSW). The small size and considerable distances between these operations makes it uneconomic to build a stationary processing plant to extract value-added products, in particular Epsom salt, from the bitterns of the three operations. This fact led SunSalt to build a containerised mobile plant that could be moved to each site to process the bitterns at the end of the salt harvesting period.Epsom salt is extracted from the bittern by further evaporation, refrigeration and recrystallisation. In this process the bittern is diluted with five per cent volume of fresh water to minimise precipitation of residual halite in the bittern. Cooling the diluted bittern to between -5 and -10¦C precipitates up to 70 per cent of the magnesium sulfate, which is recovered as 85 to 96 per cent purity Epsom salt by filtration. This product is marketed as an industrial grade Epsom salt. Higher purity (up to 99.9 per cent) Epsom salt (USP or BP grade refined product) is made from the industrial grade product (raw Epsom salt) by recrystallisation.The containerised mobile plant was commissioned in December 2002. The raw Epsom salt generated in the mobile plant is refined to a higher purity Epsom salt in a separate plant located in Mildura. The Mildura plant was commissioned in December 2003.The CSIRO-SunSalt collaboration has demonstrated that the saline waters can be processed into a useful resource, and in addition could create jobs and a new skill base in regional Australia. The production of Epsom salt locally in Australia, which is worth currently about $A600 per tonne, removes the need to import over 3000 tpa from overseas with a net positive impact of $A2 million on the balance of trade.

Jan 1, 2004

The general types of industrial behaviour of liberated valuable sulfide minerals in the 0 - 10 ¦m size fraction are described and tests to explore on site at a concentrator the general nature of any deficient behaviour are discussed. In addition, the general types of behaviour of the gangue minerals in this size fraction are also described in terms of their mechanisms for recovery. These behaviours are also discussed in terms of the type of grinding device and grinding environment in which they were produced and the target grinding product size. Major recent improvements in the industrial capabilities of grinding devices are discussed.Present difficulties in characterisation of particles in the 0 - 10 ¦m range are described and desirable improvements for the future are outlined. Further, desirable improvements for industrial processing of valuable minerals in this size range are discussed along with some remedial actions.

Jan 1, 2005

The epizonal Ag-Pb-Zn vein deposit at San Bartolome is characterised by a base-metal sulphide assemblage containing the spectacular development of interpenetrating, bladed networks of pyrrhotite which have been replaced by marcasite and pyrite. A similar assemblage displaying the same crystal habits and textures are also a diagnostic feature of the Sn and Sn- Ag deposits of Bolivia. On this basis, it is reasonable to conclude that both deposits were formed from fluids of similar nature and origin. Although no economic accumulation of Sn is known in San Bartolomr, further comparison of the geologic setting, age, mineralogy, fluid inclusion data and magmatic association of this deposit with the Bolivian systems has highlighted additional similarities consistent with a hypothesis that more extensive Sn mineralisation might exist in the San Bartolomd area.

Jan 1, 1995