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Electronic detonators bring a fundamental and radical change to the potential of rockbreaking operations. The immense technical challenge of safely merging electronic systems with explosives has been largely overcome, but a surprisingly difficult obstacle has been to convert users to the much more capable electronic systems, in routine as opposed to exotic applications. Unit cost is probably the main point of resistance. For years papers have confirmed significant improvements in blasting results, feeding through to enhanced bottom line value for the whole operation: much reduced environmental impact, and improved control over fragmentation, muckpile shape and overbreak. In Africa, a number of operations have been employing the technology for sufficient time to see enduring improvements in throughput, control and cost structure, and these improvements have fed through to the planning process: both the cost and the benefits are part of the plan. This has essentially rendered very unattractive the option of reverting to pyrotechnic systems and incurring the penalties previously unseen but now understood to be avoidable. Examples given are of improved throughput at opencast and underground mines, and greatly extended life at an urban quarry. The general experience of management in implementing the technology is that it over-delivers: adopted to solve one particular problem, significant other issues are also addressed. These extra benefits were quite logical, but not at all obvious prior to implementation. Exploring this reality is essential for harvesting the benefits of the technology sooner rather than later.

Jan 1, 2004

The Musselwhite mine, located in northwestern Ontario, Canada, has been an underground narrow-vein gold producer since the spring of 1997. As an exploration project at the feasibility stage, much effort was undertaken to generate a geostatistical resource model that would integrate the orebodyÆs geological features, as well as the controls on mineralisation. Today as an operating mine producing over 200 000 ounces of gold per year, reconciliation studies of the tonnes and grades treated at the mill, with the feasibility model, for longer time periods, and with the grade control models, for shorter time periods, show results that are in good agreement. It was clearly demonstrated with the reconciliation to production, that the key to good reconciliation remains in the proper selection and application of the geological resource estimation method. The application of a grade interpolation technique capable of capturing threedimensionally pertinent geological features, as well as accounting for spatial grade continuity, proved to be successful in the predictability of tonnage and grade at the Musselwhite mine. Along with good mine practices, this approach, which was carried through to the operation, has produced excellent reconciliation results. The ongoing reconciliation studies at Musselwhite allow for a constant revision of the grade estimation strategy. In return, this optimisation process adds value by raising the accuracy level of production expectations. As this is an evolving practice at the mine site, further implementation developments are recommended to integrate these reconciliation procedures on a more regular basis.

Jan 1, 2002

By S Leary

Diamond drilling since early 2006 has identified an epithermal gold-silver (Au-Ag) deposit beneath 140 m to >400 m of cover. The Fruta del Norte discovery had an inferred resource estimate of 58.9 Mt grading 7.2 g/t Au in October 2007. The mineralisation is hosted by Mid-Late Jurassic andesite and andesite porphyry in a regional fault zone beneath mainly post-mineral but in part syn-mineral Late Jurassic cover. The intermediate sulfidation-style deposit formed before and in part during deposition of epiclastic cover in the fault related pull apart basin. In addition to its size and obvious economic importance, the widespread occurrences of visible gold and exquisitely preserved epithermal textures will make Fruta del Norte an important learning tool for explorationists seeking epithermal mineralisation in theAndes and elsewhere. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By C Rees, M Predebon, J Denney

It has been said on many occasions that æthe future of the mining industry of Australia, and indeed the world, lies in the hands of the studentsÆ. As a student, this can be a daunting, yet very exciting, statement. If nothing else, it is a direct challenge to the student body of the mining industry to take responsibility for its direction æafter 2000Æ. However, for the students to embrace this challenge, some responsibility must be borne by the universities and the industry itself to provide some direction and encouragement. Perhaps, therefore, the real challenge is to find the right balance between students, industry and education to best prepare the students for a career in the mining industry. The future industry will demand students who are capable and willing to adapt to change and technology and able to exert the vision and leadership required to ensure the mining industry continues to thrive well into the next century.

Jan 1, 2000

By L M. van Niekerk

The mining of iron ore is a high volume low margin business because the value of this commodity is significantly lower than that of base metals. The main metallurgical challenges in most of the iron ore projects proposed for treatment nowadays have been in finding the optimum flowsheet for the treatment of magnetite ores, mixed magnetite-hematite ores and even ores that have banded ironstone formations (BIF). The associated plant designs incorporate very high capacity milling systems to grind the ore down prior to magnetic separation and in being highly capital intensive requires substantial investment in mega processing plants with associated infrastructure to mill down the run-of-mine ore to the desired treatment size for upgrading.To minimise the cost of infrastructure, better beneficiation techniques and technologies are being sought to assist in reducing upfront ROM feed to allow for reduction in overall treatment plant footprint necessary in extracting the desired downstream product. This paper discusses such beneficiation techniques and advancement in technologies for the upgrading of coarse and fine iron ore utilising dense media separation (DMS), jigging, wet magnetic separation, dry magnetic separation, flotation and x-ray processing.Another group of iron ore projects involve the mining of hematite ore below the water table. Often the mined ore is wet and sticky. This combination requires high capacity processing of feed material utilising large scrubbers or attritioning units to effectively remove the slimes component present in the feedstock. The fines removed, usually below 1 mm, are then discarded in large tailings storage facilities. Approaches to recovering the saleable material contained within these fines will also be investigated in this paper. This not only implies possible reduction in slimes discard footprint, but also holds potential benefit in augmenting overall yield and recovery of hematite product.CITATION:van Niekerk, L M, 2013. Fine and coarse iron ore beneficiation - An evaluation into global technologies and techniques, in Proceedings MetPlant 2013 , pp 584-598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By G, F Beach, D Jazzini, R Rounsley

Over the past 20 years within Australia, there have been a number of incidents at mine sites where ammonium nitrate-based explosives have reacted with certain rock types containing sulfide minerals. These rocks have commonly been referred to as æreactive groundÆ. These reactions have frequently led to fires (particularly in ground susceptible to spontaneous combustion) or premature detonation of the ammonium nitrate-based explosives. Clearly, this introduces an element of risk when using ammonium nitrate-based explosives in these areas. Dyno Nobel has been proactive in developing ammonium nitrate-based explosive products that can be used in these types of æreactive groundÆ environments that minimise the risk of premature detonations occurring. A system for assessing æreactivityÆ of sulfide containing rocks has been developed that can be used in the field. Previous literature has been reviewed, identifying Differential Thermal Analysis (DTA) as the most common method for determining the æreactivityÆ of the ground. In the present investigation, DTA has been rejected as a suitable technique for determining ground reactivity, since it measures thermal reactions at higher temperatures over short time periods, conditions that are unlike those in the field. For example, ground at ambient temperature has been found to react with ammonium nitrate-based explosives over long time periods, reactions that are unable to be evaluated using DTA. Other more suitable techniques have been developed to monitor rock conditions that can be measured in the field and give a good indication of potential ground æreactivityÆ with ammonium nitrate-based explosives. Dyno Nobel is currently investigating the reaction mechanisms of spontaneous combustion in reactive ground, the decomposition mechanisms of ammonium nitrate and the role of inhibitors in ammonium nitrate-based explosives. Once complete, this fundamental research will lead to the further development of even lower risk ammonium nitrate-based explosive products for use in æreactive groundsÆ in a variety of mine environments.

Jan 1, 2003

By G Newling

Zinifex Rosebery Mine is a lead-zinc underground mining operation located at the base of Mount Black, on the West Coast of Tasmania. Mining activities at the Rosebery Mine have been undertaken for over 100 years, and it has been operating in its current form for over 60 years. A large surface and underground exploration drilling program over the last 18 months has increased the mineÆs expected mine life from five to 12 years, with expectations that over the next 18 months as the program continues this will swell to 20 plus years. Zinifex Ltd secured Rosebery Mine in April 2004 and commissioned a detailed life-of-mine (LOM) study on all aspects of the operation. One of the most detailed sections of this report was on the state of the current ventilation system. It was identified in this report that for mining at the current depth of approximately 1100 m to continue a minimum 30 per cent increase in ventilation quantity was essential, as well as a likely requirement for a refrigerant cooling plant for each of the two deepest panels, the K and P lenses. It was identified that Zinifex did not have personnel with the expertise in underground refrigeration to manage and implement a project of this nature. A second report was commissioned with Bluhm Burton Engineering (BBE), a South African firm specialising in both surface and underground large-scale refrigeration plants. BBE concluded that two refrigeration plants were required to provide the necessary cooling power in the lower sections of the mine. In 2005, with BBE as technical consultants, Zinifex Rosebery Mine embarked on a project to commission two underground refrigeration units capable of lowering the wet bulb temperature at the decline face by four degrees centigrade. This paper is intended to give the reader an overview of: Rosebery Mine operations,Rosebery underground refrigeration project,technical difficulties associated with implementing an underground refrigeration system, andkey learnings to date.

Jan 1, 2008

The role of automation in the environmental management of the various stages of mining projects is discussed. Remote sensing can be useful in the exploration phase, but tends not to have sufficient resolution for individual operations. Automatic samplers, whether for meteorology, air or water, are widely used, but can have operational problems. The environmental scientist, the electronics engineer and the computer programmer must combine in the future to develop products which are applicable, robust and simple to use.

Jan 1, 1985

By Johnston RF

The motivation for, the structure of, and the overall features of a block release Graduate Diploma program designed for practising minerals engineers are outlined. It is demonstrated that because of the very specific subjects taught, the course has the potential to effect significant improvements in operating plant performance. Through lifting the skill level of the participants and therefore advancing their career prospects, the course can raise staff morale and improve plant performance and productivity in their work place.

Jan 1, 1993

The excessively high cost of production in underground coal mines has made the survival of many coal mines around the globe economically non-viable. The global competitive coal market speaks itself of the desirability of a lower operating cost in conjunction with a higher productivity performance, particularly in underground coal mines, and calls for an optimal production planning under a host of constraints. Such a task of optimal planning is not an easy exercise like that of traditional planning based merely on intuition, experience and subjective judgement. It essentially demands a thorough understanding of the complex interaction of mine sub-systems for judicious application of optimisation tools and techniques available with operations research. A few large mines around the globe have made an effective use of a sizeable number of operations research packaged programs for optimal decision-making (Grayson, 1989). The success of practical applications of operations research techniques made in a variety of mining problems in large mines in different parts of the world will hopefully make inroads to smaller mines in years to come. The present paper is an addition in the series of such applications of operations research tools to mining problems, particularly with reference to an underground coal mine in India. The paper is based on research work (Jawed, 1990) and deals with the development and use of a mathematical model for production planning in underground coal mines under multiple objective environment subject to a host of constraints.

Jan 1, 1995

Installation of spirals as roughers and scavengers in the gravity and regrind recovery circuits has allowed rejection of large weight fractions to tailings, thus contributing to increased mill capacity.

Jan 1, 1978

By B Tessier

Checking the quality of a blast may be considered as subjective. Checking this quality will require measuring objective parameters. One of them is the resulting fragmentation of the blasted product. Numerous fragmentation æmeasuringÆ systems have been developed and marketed, based on image-processing. This presentation of FragScan will illustrate advantages and difficulties when using such a system. FragScan is essentially defending a policy of large and representative sampling. The purpose is to show how fragmentation is discriminating both productivity and profit of quarry operations on a blast-by blast basis. The next step will then be to ædriveÆ the blasting process to reach a æbetterÆ fragmentation. Other applications require the fragmentation as an essential result: this is the case for large boulders used in structure-reinforcement. Several case-studies have shown that FragScan can be used for quality-control, checking size-distribution of the product according to the requirements of the end-user. Only clear thinking about the precise use of such a æmeasurementÆ will further the success of this task.

Jan 1, 2001

By Tenorio J. A, Vieira C. B, Sobrinho P. J N

This paper shows a review of bibliography and actual situation of the plastics injection into blast furnace. Some information about results and experimental practice with plastics waste are presented as well as the development of the injection plastics's technique.

Jan 1, 1999

The types of risk to mining projects using environmental protection as justification are examined. In Australia, Governments, whether Federal or State, enforce environmental legislation. The way they do This has an impact on the risk to a project. This is discussed and examples are taken from the Northern Territory uranium industry. Special reference is made to mine closures where the roles are not yet entrenched.

Jan 1, 1994

A review of the motivation of personnel in the open cut mining industry. The effect of social, geographic, environ- mental, organisational, union and other factors on employees' motivation as assessed from job experience and from an attitude survey. An appraisal of where we should be heading and what influence management can have on the motivation of employees.

Jan 1, 1980

Reliability is not only important in coal mine planning, production and control. Reliability is also most important, and indeed is fundamental, to successful coal exporting.Coal preparation, blending, distribution, marketing and utilisation are areas of the coal industry in which reliability can be critical to coal exporting. Major elements of reliability which impact on coal exporting include coal quality, supply performance, -coal ownership changes, governmental regulations and policies, market reputations and differences in export markets.

Jan 1, 1991

By Appleyard B

The objective of this paper is to provide a brief to The AusIMM initiative which originated in 1996 and has developed from a concept proposed by Ric West, a Sydney consultant. The notes which follow are drawn primarily from a paper included in the Ironmaking Resources and Reserves Estimation Seminar volume presented by Vivienne Snowden, a member of the Towards 2000 Steering Committee and of the JORC committee.

Jan 1, 1997

SLon magnetic separators utilise the combined force fields of magnetism, pulsating fluid and gravity to continuously beneficiate fine weakly magnetic minerals. They possess the advantages of high efficiency, low operative cost and high reliability. Until now there were about 600 SLon magnetic separators widely applied in processing oxidised iron ores, ilmenite, manganese ore and many other minerals. In this paper, several typical oxidised iron processing flow sheets with SLon magnetic separators are introduced.

Jan 1, 2007

The purpose of this paper is to review recent approaches by regulators, employers and employees and their associations to the introduction of flexible employment practices and the management of fatigue related risk. More importantly, it will focus on developments in our law either through legislative change and cases which have dictated trends. The paper particularly considers the limitations imposed by occupational health and safety legislation to resist or limit the move to flexible workplace practices on the basis that such practices are unsafe.

Jan 1, 2003

The purpose of this paper is to explain the basic structure of how minerals are marketed, whilst highlighting the essential factors that mine management needs to be confident are incorporated into a mineÆs marketing strategy. The traditional mine management approach to marketing has been to defer its scrutiny to the marketing manager and take a largely passive role. It is this paperÆs assertion that mine management needs to become more proactive and provide greater strategic input into the marketing process. Irrespective of what mineral your mine produces, the key marketing principles remain constant and need to be understood and managed to extract the full benefit on behalf of the mining asset. From a mine management perspective, success is ultimately linked to understanding these marketing principles and ensuring that they are effectively addressed by your mineÆs marketing strategy. This paper will unashamedly attempt to simplify marketing by explaining how the basic fundamentals of supply and demand set market direction, the importance of a comprehensive marketing strategy, the importance of customer relationships and how contracts and prices are typically negotiated. This paper will use examples from the metallurgical coal (met coal) industry to highlight these points. The paper will also provide a template for developing the critical mine interaction that needs to exist between the marketing department and management to develop a æwhole of mineÆ approach to marketing. It is this core group that will be strategically responsible for delivering the commitments your mine has made to your customers. For mine management not to be actively involved in this process puts at æriskÆ the hard won production and cost efficiencies achieved at your mine and ignores the opportunity to maximise your current and future revenue streams. And whilst this paper recognises that is arguably unreasonable for mine management to become æmarketing expertsÆ, it also argues that it is unreasonable for a mine management to divorce themselves from the process.

Jan 1, 2006