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The treatment of the Broken Hill ores has,undergone many changes during the last ten years, and it may be of interest to some of the members to know what are the main lines on which the Proprietary Mine works at present. It must be understood that the want of absolute uniformity in the treatment amongst the various mines at the Barrier does not prove that some of the mines are working on wrong lines, for the ore is not exactly the same along the whole line of lode; this necessitates a variation in treatment, although generally only in detail.At the Proprietary Mine the ore is all mined by contract the miners are paid so much per ton for clean ore. The ore in the mine in most stopes is mixed with gangue, and the inclination of the uliners is, of course, to mix gangue with the ore, so as to be paid for as large 3 tonnage as possible. This is quite natural clean ore is easily distinguishable from clean gangue, but most lumps are a mixture of clean ore and gangue in varying proportions. The miner will naturally throw into his heap pieces which he considers still good enough, whilst the management may consider these pieces just a trifle too poor; consequently a check must be kept on this.This necessitates the first operation to which the ore is submitted. 'The trucks tare 51 cwt.; average load 21 cwt.), as they are loaded underground, have a ticket attached::showing to whiyh contract they belong on arrival at the top of the shaft they are passed over a weigh bridge...

Jan 1, 1907

In order to understand the technique, basic theoretical principles of radiation emission and in- strumentation theory are reviewed. Methods of surveying, reduction of data and interpretation are outlined. Other applications of the technique (e.g. in airborne geological mapping), as well as its specific use in uranium exploration, are discussed. By means of case history-type examples the successful applicant of gamma-ray spectrometry, as a tool in Australian mineral search, is demonstrated.

Jan 1, 1969

By A K. Ghosh

"Inrush of water is always an issue, especially for mines located in heavy rainfall areas. Nowadays, mining companies and research institutes have developed many advanced technologies for study and analysis of hydrological processes. In this paper, an advanced method is introduced, which uses the Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data in the Geographical Information System (GIS) platform to simulate the stream distributions around two specific mines: Super Pit and Griffin coalmine in Western Australia. The impact of this approach is important because it reduces the time and economic cost by creating a high spatial resolution hydrological map in the specific areas. The study identifies the flow path of the run-off water, which helps in adopting a suitable water management plan surrounding the case study mines. The results match with the ground reality. Based on the results, the stream structure around Griffin coalmine is more complicated than that of Super Pit. The bifurcation ratio and drainage density are computed to estimate the subsoil permeability characteristics of the two mines. Recommendations have been put forward to prevent and reduce the potential risks of water accumulation around the open pit mines.Citation:Ghosh, A K, 2016. Application of Shuttle Radar Topography Mission Data in Hydrological Analyses of Super Pit and Griffin Coal Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 162–169 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By D Jeffery, R Whittering, G Lane

Most aspects of process design are best addressed via bench scale or pilot plant scale test work. However, as experience is gained, fundamental or indicative data can provide more than adequate information to manage the risk associated with some process aspects of concentrator design.Historical precedence exists where minimal design test work has resulted in successful projects. On many occasions benchmarking, sometimes supported by fundamental data such as mineralogy, has been used to successfully develop effective process plant outcomes. Of course, this style of approach is most common with æfast trackÆ projects and often comes with the usual surprises that result from inadequate geometallurgy to define the project cash flow.This paper explores the risks and opportunities associated with the various facets of process development and design for a base metals concentrator. The paper is intended to provide guidance to project managers rather than address the technical aspects of process engineering.CITATION:Lane, G, Whittering, R and Jeffery, D, 2012. Benchmarking versus test work - How should you manage process risk?, in Proceedings Project Evaluation 2012 , pp 49-52 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By T O Aspinall

The Australian mineral industry involves a diverse range of expertise and skills. Within that, the mining industry, representing mine planning, mine management and equipment operation, has capital intensive, high productivity equipment and a small but skilled workforce. Continuing education for all personnel in the workforce after formal school courses will be an important contribution towards improving competitiveness. The non-tertiary sector represents a significant proportion of the workforce and requires as much attention as the tertiary educated group. Competency Based Training is now being developed for the mining industry in Australia under the National Training Board and the mining industry is well represented in establishing standards and curriculum. TAFE is a major source of accredited courses but some mining companies are also developing internal courses not necessarily for external accreditation. Articulation of such accredited courses to tertiary mining engineering courses has been considered. The education and training of equipment operators through continuing education requires attention to operating skills, an understanding of the productivity factors under the direct influence of the operator and providing product quality to the customer. The education and training of mining engineers has been widely covered and continuing close involvement of the mining industry is required to ensure well balanced courses in technical and interpersonal skills as well as motivation to continue learning for life. Postgraduate research is a part of continuing education but the mining industry has to continually address the adequate recognition of post-graduate qualifications for the increased technical or management expertise and the development of better analytical and problem solving skills which can be directed towards improving competitiveness. More attention has to be paid to providing adequate financial incentives to attract suitable students, particularly after attaining some experience, and to address their professional career path with a company so they are not significantly disadvantaged by undertaking post-graduate studies. The Chartered Professional Engineer status as provided by The Institution of Engineers, Australia to qualified candidates is being considered by The Australasian Institute of Mining and Metallurgy as a further recognition of a member's specific expertise and competence in mining and metallurgical engineering. Continuing education plays a major part in the maintenance of the expertise and competence required for a professional engineer to develop and also to retain chartered status. Continuing education will be a significant part of the education and training of all the mining workforce towards improving the competitiveness of the mining industry. The major challenges will be the motivation of all towards lifelong learning and the integration of the various programs towards providing the opportunity for a steady and satisfying career progression.

Jan 1, 1994

By T Alexieva

Since the early 1900s the geotechnical community has investigated every significant failure of a tailings dam, improved our knowledge of the behaviour of the tailings storage facilities, developed analysis methods, compiled lessons learned, and committed to zero failures. The rate of occurrence of tailings dam failures has reduced since the 1980s, however, failures continue to occur and continue to surprise us. At BHP, we have decided to take an approach to the tailings management that is similar to the approach to safety. We are looking at ways to eliminate, substitute, separate or engineer around the hazard (tailings dam failure). As such, our ultimate long term goal would be to eliminate the need for new tailings facilities. Unfortunately, we have not developed yet technologies for extracting many of the common metals and minerals without producing tailings. Our shorter term goal is to substitute the current conventional slurry tailings facilities with less risky dryer facilities. We are working with vendors and research organizations to develop technologies that can be efficiently applied on a large scale. At the same time, we are committed to using the best available engineering to reduce the risks associated with our existing and new conventional tailings facilities. The best engineering can be achieved by people with the appropriate education, experience, attention to detail, discipline and authority. We have implemented a system of governance to make sure, we have the best engineering applied to all our facilities, considering the specific conditions at each site.This paper presents the current tailings governance process at BHP, and the initiatives that were undertook towards achieving a zero failure goal. CITATION:Alexieva, T, 2018. Tailings governance, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 2–7 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

This paper summarises the influence of slurry rheology on the grinding throughput of batch laboratory and continuous plant-scale mills operating in open and closed circuit configurations. The results of controlled changes in percent solids, particle size, slurry temperature, and viscosity control chemicals are demonstrated. An underlying rheological explanation of the above factors is offered which involves tying the specific rates of breakage that are occurring in the mill with the specific rheological character that the slurry is exhibiting at any given set of operating conditions. Some industrial scale operating guidelines are presented which have proven useful in increasing the net pro- duction capability of grinding circuits.

Jan 1, 1978

The last decade has seen a very rapid development in TBM tunnelling. Some trends are purely technical or economical and others relate more to preferences of different interests. Power levels have more than doubled and thrust levels too. Shield machines are developed to be able to handle harder rock and the open TBMs are made more feasible for `difficult' rock. What is right and what is wrong is more a matter of opinion, but one thing is certain: TBMs now are a useful tool and no longer an experimental work-shop for the enthusiasts.This paper highlights some recent developments and indicates some probable future ones. A few features that have increased the open TBMs' ability to cope with ever harder rock and also to overcome problems with poor rock are discussed in detail, using the Atlas Copco JARVA Mk 27 -the most powerful TBM built so far - as a reference.

Jan 1, 1993

By T Sprague, D Pateman

"The Gosowong Gold Project is owned and operated by PT Nusa Halmahera Minerals (PT NHM), an Indonesian company 75 per cent owned by Newcrest. It is located on Halmahera Island, in the North Maluku Province of the Republic of Indonesia, approximately 2450 km north-east of the national capital, Jakarta (Newcrest, 2017).Kencana is one of two underground gold and silver mines at the Gosowong Operation where ground conditions vary from competent to very poor. Development headings occurring in poor rock mass conditions require high capacity ground support including long tendon cable bolts. Manual installation of cable bolts in these development headings has been a time consuming process due to borehole collapse, blockages requiring subsequent re-drilling and a minimum eight hour grout curing time interval. The installation of cable bolts including the setting, plating and tensioning can impact the critical path for development heading advance resulting in development cycle delays.A review was conducted by PT NHM on current industry practices for alternatives to manual cable bolting. PT NHM subsequently approached Minova to assist with the development and trialling of self drilling anchors (SDAs) installed using jumbos with a rapid setting pumpable resin, CARBOTHIXTM. A series of system development trials were conducted and a reliable bolting system was developed utilising the existing jumbo drilling fleet with minimal required modifications.The system developed was a ‘one pass’ bolting process to install and grout SDAs using a two component resin with a remote, mechanised system. Improvements achieved from the system include: eliminating hole closure issues and more immediate support in poor rock mass effectively reducing personnel exposure to poor ground conditions by removing the requirement to access the drive backs reducing grout set time with full installation times for 6 m SDAs averaging 25 min.The resin grouting system has now been successfully implemented to effectively manage areas of poor ground conditions and to accelerate advance rates in high priority headings.CITATION:Pateman, D and Sprague, T, 2017. Development and implementation of a long tendon bolting system utilising resin grouting technology, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 16, 2017

By P M. Hetherington, F A. Pym, M P. Murphy, K E. Crook

Consultants in the mining industry have the opportunity to visit interesting deposits all over the world. Each deposit has its own set of challenges to face when it comes to defining and understanding the deposit geology and the economics to make it viable for extraction. Some of the challenges can include appropriate data capture, sampling techniques, structural characteristics, geochemistry, geophysics, lithology definition, and economic boundaries. It is essential that the practices used at each deposit (eg drilling, sampling, geological modelling, resource estimation etc) are documented and the results obtained are robust and defensible. The Competent Person is not always aware of instances where their resource estimation practices have not been substantiated. ‘You don’t know what you don’t know’ is a phrase frequently used during a mineral resource audit. Technical work to substantiate drilling, sampling, density, assaying, geological modelling and estimation processes is not always completed. Audited Competent Persons often comment: • ‘I was unaware that this was required.’ • ‘I have not had training in this area and do not know how to complete the checks required.’ • ‘This is how we’ve always done it.’ Examples of audits where it was found that geological practices were not substantiated are examined here. A discussion is included on why substantiation of these practices is important, and potential reasons as to why there are instances of unsubstantiated processes and practices are discussed.

Mar 22, 2022

The sulphide ores of the Kalgoorlie goldfield have long been looked upon as' refractory, involving special metallurgical treatment. For many years two kinds of treatment have been practised-(l) wet treatment, including fine grinding, amalgamation or concentration of the free gold, concentration of the sulphide minerals with subsequent roasting and cyanidation, and cyanidation or bromo-cyanidation of the residue from the concentrating operation; (2) dry-crushing of the ore and roasting the whole of thecrushed ore, amalgamation of the gold in the calcine during fine grading, followed by cyanidation. The wet treatment was advanced a stage further when, in 1929, the Lake View and Star Ltd. adopted large scale flotation. As a consequence, however, further metallurgical problems were introduced. This paper covers the investigation, ,of one of the most prominent of these problems.Flotation preceded by strakes was satisfactory to a point.The flotation concentrate consisted largely of auriferous pyrite and tellurides, and the gangue minerals in the concentrate were practically barren.Several sources of loss of gold values were, however, found to be associated with this circuit, viz.-(a) There was the loss of gold in the flotation tailing.(b) Loss by dusting during roasting of the flotation concentrate.(c) Loss of gold in the cyanided residue.

Jan 1, 1937

By R Brown

The Singapore Land Transport Authority Contract C917A is for the design, construction and completion of all outstanding works under the original Contract 917, including taking over the design and construction responsibility for the works carried out by previous contractor. Construction works connect the bored tunnels between the stations at King Albert Park and Sixth Avenue on the Downtown Line two in Singapore.The original contractor became insolvent leaving the works incomplete. On 29 August 2013 McConnell Dowell were awarded the completion contract following a fast-tracked tender process. The completion contract required a quick start and therefore the recruitment of some of the original workforce. A large majority of the original workforce was from Malaysia, Indonesia, China, Philippines, Bangladesh, India and Thailand. In order to ensure that the safety standards were upheld, and that the new workforce embraced a safety culture, a behaviour based safety (BBS) approach was implemented.The BBS approach was implemented to overcome the existing poor cultural safety behaviours, and to ensure that high standards and expectations for safety were implemented. This ensured that the workforce were comfortable in identifying hazards, avoiding shortcuts, and changing poor safety behaviours.This article outlines how a BBS program was delivered on the C917A project, containing defined goals, communication tools, and assessment and feedback models.CITATION:Brown, R, 2014. Behaviour-based safety with a foreign-based workforce, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 65–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By DJ McKEE

Process control emerged in the mid-1960s as a new and exciting method of improving the performance of mineral processing operations. The early Australian developments, principally in Broken Hill and Mount Isa, were based on pioneering work in instrumentation, the availability of small digital computers and a particularly effective partnership between companies with technological foresight and University and CSIRO research groups. Initial progress was rapid and within ten years many plants were committed to process control. Process monitoring is now routine and most circuits have some level of control. However, few plants have comprehensive optimising control systems as the difficulty of developing control strategies which can cope with the wide variety of conditions encountered in most mineral plants has been fully appreciated. This paper summarises past experience and assesses the degree of application of different forms of process control in metallurgical plants. Barriers to the effective utilisation of opt rising control are identified and some suggestions for advancing the application of control are made.

Jan 1, 1992

By Wright G. A

The objective of refining in steelmaking is to reduce the concentration of impurity atoms, e.g. sulphur, phosphorus, from an initially high level to a specified low concentration. A two-film theory of refining is presented in which the rate of

Jan 1, 1980

By Nixon TR

The Australian Coal Industry Research Laboratories Ltd. (A.C.I.R.L.) MINVENT computer program can be used to simulate existing and projected colliery ventilation requirements. New collieries can be planned using a database of ventilation parameters which were ascertain- ed by A.C.I.R.L. surveys at selected collieries in N.S.W. and Queensland. Several techniques are used in both the formulation of the database and in the evaluat- ion of a ventilation system, prior to analysis by the MINVENT program. The analysis of a ventilation system requires the measurement of air quantities, pressures and hence airway resistances. All resistances are calculated at standard air density of 1.205 kg/m3. Air densities are derived from barometric pressure and wet and dry bulb temperature readings. Airway frictional and shock losses, leakage through stoppings and overcasts, flow of air through regulators, face resistance and resistance of anomalous ventilation features are related to the typical Australian measured data presented.

Jan 1, 1983

By V Lawson

Vale’s Sudbury Clarabelle Mill processes Cu/Ni ores from a number of mines in the Sudbury basin in Ontario, Canada. Bulk sulphide flotation produces a copper-nickel concentrate with pyrrhotite as the major diluent. After successful commissioning of the Voisey’s Bay Cu/Ni Mill (VBN) in Labrador, a miniplant campaign on Clarabelle ore with the VBN flow sheet produced a significant recovery improvement over current performance. In 2001, the Mill Redesign Project moved grinding energy into rock/sulphide and pentlandite/pyrrhotite separation and in 2006 Cu/Ni separation was re-introduced to Clarabelle Mill to produce a saleable Cu concentrate. The projects were a great success. What remained was to simplify the Clarabelle flow sheet by introducing the missing components found in the VBN flow sheet. This project known as CORe has evolved through many stages including the mining boom and surviving the 2008 economic downturn and it is scheduled for completion in mid 2013. This paper outlines some of the challenges faced in this major brownfields project – organizational, technical, financial and operational.

Aug 8, 2011

By K Gardner, R Fraval, V Singh

Using new technology to create optimised infill drill programs in underground or open pit settings, it is possible to quantify the value of a drill program. The computer designed programs are optimised to uplift the most amount of resource possible into the specified resource classification, while honouring geological, spatial, equipment and budgetary constraints. When designing ‘by hand’ balancing all these factors is a time-consuming effort with no real way to determine metrics on ‘how good’ a program will be. The optimisation considers many factors allowing geologists to apply critical thinking and domain knowledge to constrain the optimisation, letting the computer do the heavy lifting of determining hole placement. Once programs have been created, they can be integrated into a production schedule. This is a critical step in determining the correct sequencing and balancing of resource availability and seeing how a program will interoperate with other tasks in the mine. For example, if drill drives are a requirement for part of the program, will they be developed in a time frame that is useful for the goals of the program? Do we risk drilling infill holes too late to add value? Do we put production at risk by not classifying parts of the model ahead of time, thus adding to uncertainty? Using software to assist with optimising and scheduling of drilling is a useful technique to save the geologists from the mundanity of manually designing drill programs and puts metrics around the effectiveness of a program and has the potential to add quantifiable value to a program. Examples will be presented that demonstrate the effective use of drill hole optimisation, comparing manual designs with optimised designs, as well as the examples that show the effective use of scheduling.

Mar 22, 2022

By A Llewellyn, M Varvari

The ventilation circuit at the FrogÆs Leg Mine was originally designed to permit mining to progress down to 440 m below surface at a maximum production rate of 500 kt/a, as per the feasibility study. The FrogÆs Leg resource has now been defined down to 640 m below surface at a maximum production rate of 750 kt/a. In order to allow for this increase in production depth and tonnage, it was necessary to upgrade the ventilation circuit.This paper outlines the upgrades to the ventilation circuit that were undertaken and the underlying rationale behind them.CITATION:Llewellyn, A and Varvari, M, 2013. Ventilation upgrade at the FrogÆs Leg Mine - Case study, in Proceedings The Australian Mine Ventilation Conference , pp 95-102 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

For the mineral industry, sustainability seems to mean socially positive and ecologically neutral mineral extraction. Mines are financed and developed in response to demand for their products. The purpose of my paper is to indicate the potential dimension of demand. As part of an unrelated study which I undertook ten years ago, it became apparent that there is a persistent relationship within communities between infant mortality and mineral use; greater mineral use corresponds to a lower rate of infant mortality. This comes as no surprise; sufficient potable water, a reliable supply of food, hygienic waste disposal, hot water and refrigeration all improve the chances of survival of the more vulnerable members of any community. The predictable provision of these facilities requires the application of minerals. This relationship is supported by a table (Appendix 1) included in the UNICEF publication, æThe State of the WorldÆs Children 2001Æ. This table lists regional infant mortality rate (IMR) statistics from around the world, including a listing for æindustrialised countriesÆ. Such countries experience an IMR lower by an order of magnitude than any other region. æIndustrialisedÆ inevitably involves the use of metallic and energy minerals. The principal use of copper is in the generation and distribution of power; it is fundamental to any industrialisation. IMR is a valuable connection because it quantifies caring for the young, a vital strategic driver of human behaviour independent of time, place, fashion or economic circumstances. I have tabulated the population, IMR and the copper demand per head of population for countries containing over 99 per cent of the population of the world in the years 1950, 1960, 1970, 1980, 1989, and 1999. These countries have been consolidated into four groups, Very High, High, Medium and Low rates of infant mortality (UNICEF has used this terminology; the Low group includes all the æindustrialised countriesÆ). The purpose of this consolidation was to reduce the volume of work, to dampen out the impact of regional wars and business cycles, and to dampen out the variable quality of information. Based on the pattern of the copper demand, population and IMR over the last 50 years, I have projected the likely copper demand in 50 years time. A dominant feature of my tabulation is the increase per decade in copper use per head and a corresponding reduction of the IMR. The word æuseÆ is preferred to æconsumptionÆ because it is estimated that over 80 per cent of all the copper ever mined is still in circulation There are two major influences at work; one is the absolute increase in population (UN estimates for 2050 are updated periodically) and the second is the movement of countries into a higher pattern of use and lower IMR. For example the Medium group in 1989 had an infant mortality rate approximating that of the Low group in 1960. With the population of the Medium group (which includes Russia and China) forecast to reach 2.6 billion in 2050, the world copper demand in that year will be significantly greater than the present figure. Nevertheless it will not be as great relatively as the increase of over 300 per cent in the last 50 years.

Jan 1, 2002

The Douglas mineral sands deposit is located 75 km north of Hamilton in western Victoria, Australia. The deposit was discovered in the late 1990s by Basin Minerals Limited and purchased by Iluka Resources Ltd in 2002. Prestrip mining commenced in December 2004, with ore mining commencing in August 2005. Douglas is the first of several projects being implemented by Iluka Resources Ltd in the Murray Basin, with all heavy mineral concentrate planned to be treated at the companyÆs mineral separation plant in Hamilton. The mineralisation at Douglas lies along the south-eastern margin of the Murray Basin. It is hosted by marine Pliocene Loxton-Parilla Sands and consists of three discrete deposits; Bondi Main, Bondi West and Bondi East. The mineralised sediments dip at a low angle to the west and lie unconformably beneath a veneer of top soil (50 - 100 mm) and subsoil (up to 600 mm) and between three to 12 m of overburden. The barren overburden, characterised by high clay content (<53 ¦m material) generally provides a stark contrast to the sandy ore, which is between 1 m (parts of Bondi East) and 15 m (Bondi Main) thick. Both overburden and ore are removed utilising standard dry mining techniques using both scraper-bulldozer and truck-excavator combinations. All ore is delivered to run-of-mine (ROM) stockpiles before being reclaimed by front end loader into the processing plant. Grade control at Douglas is based around visual dig control aided by high precision survey, which enables accurate reference to the resource drilling and block model data. Vertical excavator faces, inclined scraper faces plus regular test pits and trenches provide opportunities for in pit mapping and sampling. This data is used to refine not only the resource estimate for Douglas but also the drilling, interpretation and resource modelling methods used for similar deposits across the basin. The foundations of the geological reconciliation process at Douglas are the in pit surveys undertaken each time the mining fleet has completed building a ROM stockpile. These surveys and the subsequent interrogation of resource models enable robust estimations of the heavy mineral content of the stockpiles, which are subsequently used to predict the daily input grades into the plant during their reclamation. Reconciliation of this daily data is then undertaken at the end of each month against metallurgical production data and plant balances. Learnings and results from the reconciliation process are used to further refine subsequent resource models and modelling methods.

Jan 1, 2009