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By I T. Ross

Sampling drawpoints in block cave mines has been a contentious issue for many years. Doubts have been expressed as to the validity of the process used at most mines. This paper outlines the sampling practice commonly in use, discusses the resulting issues associated with reconciliation and drawpoint closure decisions. The paper also looks to the future and highlights issues for some block cave mining operations currently planned to have in the order of one thousand active drawpoints. It is likely that these operations will require a new approach to drawpoint sampling. There are several potential technologies currently available although some appear to be better suited than others to replace the current approaches. CITATION:Ross, I T, 2012. Sampling in block cave mines, in Proceedings Sampling 2012 , pp 81-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

Correlation of Air Recovery with Thin Film and Froth Stability in Flotation

Sep 13, 2010

By T Baumgartl, J Burgess, B Emmerton, P D. Erskine

Large-scale open cut mining in the Bowen Basin has been undertaken for over 40 years. During this period, improved mechanical capability and economics have allowed extraction to greater depths, resulting in post-mining landforms of increasing height. Rehabilitation practitioners face significant challenges in stabilising these landforms and require a comprehensive understanding of the Bowen Basin Coal Measures strata likely to be disposed of during mining. Knowledge regarding the potential behaviour of differing spoil materials (following disturbance) provides a rationale to maximise short- to medium-term surface stability of constructed landforms by identification, salvage and advantageous reuse of cladding resources as a means to minimise erosional risks.CITATION:Emmerton, B, Burgess, J, Baumgartl, T and Erskine, P, 2016. Bowen Basin coalmine spoil classification for improved mine rehabilitation outcomes, in Proceedings Life-of-Mine 2016 Conference , pp 142–147 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By B M. Guerin

In this paper, some of the constraints to applying bioremediation to the decontamination of polluted soils are introduced. Particularly, attention has been given to those associated with the geology of the polluted site. Areas which require further research have been addressed and indicate that geologists will play a key role, alongside microbial ecologists and engineers, in designing and implementing bioremediation strategies.

Jan 1, 1992

By R Shaw, T T. Neidel, C Adams

Sampling equipment manufacturers endeavour to ensure that the mechanical equipment installed in sampling systems are designed and manufactured to adhere to the requirements of the International Organization for Standardization (ISO) or other standards relevant to the application. The mechanical parameters necessary to achieve these standards can be well controlled and requirements such as constant speed can be met through good mechanical design and engineering. However, when the equipment is installed and put into operation, the ISO compliance of the system is out of the hands of the equipment manufacturer and handed to the operator, who may be a generalist control system integrator.Making a sampling system perform according to standards, and being able to monitor and report on compliance require that the sampling system knowledge and the control integration is combined and applied in an integrated approach. Using a dedicated library of control routines developed for sampling can change a system from having compliant equipment to being a compliant system. The library has to include monitoring of relevant parameters and control and reporting on sampling parameters.CITATION:Neidel, T T, Adams, C and Shaw, R, 2014. Control and monitoring of International Organization for Standardization compliance for industrial sampling systems, in Proceedings Sampling 2014 , pp 121–126 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By S SSdbom

A comparison was made between chemical analysis and ocular mineral/rock classification in health-based risk assessment of historical mine waste produced between 1625 and 1975. Large parts of the mine waste are heavily weathered and secondary minerals are abundant. The field was divided into several areas from where composite samples were collected. Seventy-five mine waste samples were selected for chemical analysis (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, V and Zn) and ocular mineral/rock classification (silicate, mica, granite/pegmatite, carbonate, iron oxide ore, sulfide ore, distribution between chalcopyrite, sphalerite and galena and distribution between pyrite and pyrrhotite). The waste has been produced in conjunction with mining a complex sulfidic ore with increasing iron oxide content (mainly magnetite) towards the northern part of the field. Elevated concentrations were found for Cd (average 26 mg/kg dw), Cu (average 3500 mg/kg dw), Pb (average 4100 mg/kg dw) and Zn (average 11 000 mg/kg dw). Large differences between average and median values indicated that the data was not normally distributed, ie the metals occur as discrete minerals (eg chalcopyrite, galena and sphalerite). The ocular classification indicated low carbonate content, chalcopyrite dominating over sphalerite and galena in most samples and an even distribution between pyrite and pyrrhotite. Both analytical and ocular mineral/rock classification data were combined into a common matrix that was evaluated using multivariate statistics. Principal component analysis (PCA) showed, for instance, that chromium and vanadium were mostly associated with harder minerals and rocks. PCA also indicated that a similar graphical picture could be obtained for chemical data and ocular mineral/rock classification data, respectively. The comparison indicates that ocular mineral/rock classification can replace or at least reduce the numbers of chemical analysis in health- based risk assessment of historical mine waste.

Jan 1, 2008

The mining of high-grade narrow vein deposits is a predominant field of activity in the precious metal sector. These types of deposits are located throughout the globe and have a significant presence in mining operations. The principle factor that has undermined the profitability and effectiveness of mining such ore zones is the substantial dilution that occurs when blasting with explosives during extraction. In order to minimise ore dilution, the thermal fragmentation mining method enables the operator to extract a narrow mineralised corridor, 30 cm to 1 m wide (according to the true width of the ore vein). By inserting a strong burner powered by diesel fuel and air into a pilot hole previously drilled directly into the vein, a thermal reaction occurs spalling the rock and enlarging the hole to 30 - 100 cm in diameter. This patented method produces highly concentrated ore, resulting in 400 - 500 per cent less dilution when compared to conventional mining methods. The mining method was conceived with the aim of mining ounces, not tonnes. This method of extraction, reduces the environmental impact of mining operations since much smaller quantities of rock are displaced, stockpiled, and treated using chemical agents. The fully mechanised equipment operated by a two-person team, maximises the effectiveness of skilled personnel, increases productivity, and reduces risks of injuries. Important economic benefits are generated for large- and small-scale mining operations alike. For large-scale operations, the mining method increases mining reserves, lowers the cost per ounce, and increases the total profitability of existing mine operations. The method also significantly lowers costs and risks of developing and mining small-scale deposits, requiring less investment capital, shortening the payback period, thus reducing the lending risk.  Combined with a small modular processing unit able to process between 100 - 300 tons per day, the method substantially lowers the financial break-even point for small-scale mining operations in a narrow vein environment. The company has been working with the technology at its Rocmec 1 mining site; results achieved and future developments are discussed.

Jan 1, 2008

Upgrading of Indonesia's Bauxite by Washing Method There were eight bauxite samples used in this research, three samples from Kijang contain total SiO2 18.36 - 29.16 per cent, Al2O3 40.12 - 48.36 per cent, Fe2O3 4.27 - 5.13 per cent, one sample from Tayan, contains total SiO2 4.69 per cent, Al2O3 38.95 per cent, and Fe2O3 19.67 per cent, and four samples from Mempawah contain total SiO2 33.5 - 44.8 per cent, Al2O3 29.8 - 35.9 per cent, Fe2O3 7.29 - 9.88 per cent. All of those bauxite ores have not fulfilled the requirement for Bayer process yet; therefore simple up-grading using a rotary drum scrubber is needed. The scrubbing process was carried out with time variable up to 60 minutes with solid percentage applied was 50 per cent and rotary speed was set up 30 rev/min. The bauxite was washed by following steps: scrubbing, screening, drying, and finally it was analysed to show chemical content. The washed bauxite produced has size fraction that is retained on the 1.7 mm of screen opening. The result of the research shows that the higher alumina content of the raw bauxite, the longer washing time is needed moreover the higher quality of the washed bauxite is produced. The highest alumina content of the washed bauxite was 53.67 per cent with the alumina recovery was 89.66 per cent and the concentration ratio of 84.80 per cent was achieved within 20 minutes of washing time of the raw bauxite (Al2O3 48.36 per cent). The washed bauxite resulted from this research is suitable as a raw material for Bayer process.

Sep 13, 2010

By P D. Munro

"This is a reprise of the paper ‘Back to the Future – Why Change Doesn’t Necessarily Mean Progress’ presented to the Tenth Mill Operators’ Conference in 2009. It was observed that the ‘boom and bust’ cycles of the industry, together with trends in tertiary education and the effects of fly-in fly-out (FIFO) operations raised serious questions about the sustainability of human capital in the mineral processing sector.In 2016 we find ourselves in a ‘bust’ after enjoying a decade of the longest commodity price ‘boom’ in a century. In the ‘boom’ did we:make any technological breakthroughs?put measures in place to improve our human capital, especially in the area of ‘professional formation’?The paper makes observations on the current performance of mineral processing engineers and the organisational milieu in which they operate. It questions whether mineral processing engineers are actually ‘adding value’ at some sites given their organisational and operational practices.Some technical trends are examined and what it might mean for mineral processing engineers.Given the above and demographic trends for mineral industry professionals, changes to the seemingly current laissez-faire model of professional development are proposed.Citation:Munro, P D, 2016. Back to the Future - Still on the Dark Side, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 341–348 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

The paper presents the development of an integrated computer aided design and planning of open cast mining, with the use of object-oriented modelling and geoinformation technologies, on the example of interaction of the subsystems on planning optimisation and freight traffics.

Dec 6, 2010

During 2009 the technical services staff at Barrick Gold Corporation's Australian Business Unit conducted a review of their five underground mines that utilise pastefill as the backfill component for these operations. Of the five mines reviewed three use dry tailings and two use wet tailings plants. The primary aim for these reviews was to determine whether pastefill was the right option to be used, and if not, what where the alternatives. The reviews undertaken focus on several areas including, paste plant operation, reticulation and barricade techniques, the geotechnical requirements for pastefill in regards to the current mining methods, the consideration of alternative methods, capital and operating cost histories compared to initial estimates, and a cost benefit analysis of pastefill against other mining methods. The main benefits from the use of pastefill is increasing the extraction of the resource, reducing or eliminating the need to leave pillars. In some mines the use of pastefill is geotechnically driven, to manage high stress environments or mining induced seismicity. A third benefit of using pastefill in some circumstances is that it reduces dilution, however it is considered that this is not a valid argument for most of the mines reviewed. At two mines no alternative to pastefill was determined, whilst differing extraction and filling strategies were potentially identified at the other three mines. The reviews developed cost benefit curves for those sites that had alternative mining methods to assist in determining whether pastefill is the right option to use for any particular stope. At the grades typically mined in each operation, pastefill was the preferred option to use. In all mines, pastefill was determined to be the best option at this time.

Nov 25, 2010

By E Westthorp, J Phillips

The detection of ethylene in mined-out ‘goaf’ areas of underground coalmines is an industry standard indicator of accelerated oxidation where the coal temperature has exceeded 100°C. If uncontrolled, this naturally occurring process can lead to spontaneous combustion and catastrophic mine explosions, such as the Moura No 2 mine explosion. Spontaneous combustion trigger action response plans (TARPs) typically use the detection of ethylene as a trigger for definite change requiring immediate reaction, which can include the withdrawal of coalmine workers.Following the completion of sealing of longwall goaves at Crinum North Mine, ethylene was often detected in trace quantities. These trace quantities were below 1 ppm and detected via the bag sampling regime, with the use of a gas chromatograph. Any ethylene detected in these instances was not associated with increased quantities of carbon monoxide to conclusively indicate a heating within the sealed area.Ethylene was only detected in a newly sealed goaf and would not remain present for a period following the sealing. As part of the longwall recovery process, the predominant roof support mechanism during the recovery was the use of timber cribs. It was decided to investigate the possibility of this timber generating ethylene.Preliminary tests were completed by placing timber specimens from several species of Australian native hardwoods in gas bags in air. Over time, some of the samples showed significant levels of ethylene within the bags.CITATION:Westthorp, E and Phillips, J, 2017. Findings from preliminary testing to determine alternative sources of ethylene within sealed areas of underground coalmines, in Proceedings Australian Mine Vent Conference 2017, pp 203–206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

Improvement of Phosphate Ore Flotation Performance Through Sized Flotation

Sep 13, 2010

Beneficiation Studies of Dolomitic Rock Phosphate in Pursuit of Zero Waste Technology - A Case Study

Sep 13, 2010

The Earth Moving Equipment Safety Round Table (EMESRT) was established by mining companies in 2006 to influence manufacturer's equipment design through a process of engagement. 2010 EMESRT member companies include Anglo American, Barrick, BHP Billiton, Centennial Coal, Collahausi, Newcrest, Newmont, Rio Tinto, Vale and Xstrata.Driven by a persistent need for retrofits to new equipment, such as haul trucks, EMESRT initially engaged with Surface Equipment Manufacturers including Caterpillar, Komatsu, Leibherr, Hitachi, Le Tourneau and Terex. These OEMs responded positively to the EMESRT initiative, welcoming the opportunity for dialogue with an aligned industry regarding human factors issues related to equipment design, rather than needing to respond to the disparate range of demands for design modifications previously received from individual customers. This engagement process is about making global sustained changes within the OEM organisations and within the mining companies. It is a very international exercise. For example, over two weeks in September 2010, a total of 21 different miners from ten different companies travelled from Australia, South Africa, Canada, Brazil, Singapore and the United States to engage with OEM counterparts who assembled from the United States, Japan, France, Sweden, Finland and Germany. EMESRT Surface Group representatives completed a whirlwind tour of the major North American manufacturers of mining equipment. Starting in Dallas (Atlas Copco, LeTourneau), this tour passed through Gainesville (Sandvik), Newport News (Liebherr), Guelph - Ontario (Hitachi) and Milwaukee (P&H Mining/Joy Global; Bucyrus), before winding up in Peoria, Illinois (Komatsu, Caterpillar). Over nine meetings, this group engaged with 129 individuals from nine OEMs. The EMESRT group welcomed miners from four non-member companies to come along for the meetings. These companies are Syncrude Canada Ltd, the Kearl Oil Sands Project - Imperial Oil (ESSO), Suncor Energy Ltd and Teck Resources Ltd.Other mining industry sectors have now expanded the EMESRT scope from surface mining to include exploration and underground mining equipment. In 2009, EMESRT was organised into four Technical Groups, consisting of EMESRT member company representatives, to focus on engagement with OEMs of surface, underground coal and soft rock, underground hard rock, and exploration drilling equipment. An advisory group has been formed to coordinate activities between all workgroups and provide strategic direction and cohesion between all activities. The Minerals Industry Safety and Health Centre (UQ-SMI) facilitates and coordinates all EMESRT activities on behalf of member companies. Building on successes with individual Surface Mining OEMs, EMESRT now aims to help OEMs in their transition to a sustainable design process that will incorporate and address specific design philosophies at the concept phase of design, so that significant improvements can be made up front for little cost within the overall budget. EMESRT members plan to educate all stakeholders, internally, within their own companies, and externally, by addressing industry associations, regulators and other end users about new ways of evaluating equipment design based on EMESRT purchasing specifications. This presentation will outline the EMESRT approach and report on progress in 2010.

Dec 6, 2010

By J Ireland, S Rose

The main outcomes of mining grade control include defining the boundary between ore and waste and then categorising the ore according to which stockpile it should be sent. A typical workflow includes using general mine planning software (GMP) – such as SurpacTM, VulcanTM or CAE StudioTM – to create three-dimensional wireframes of mineralisation domains, which are used to flag the relevant samples of interest and constrain estimation during block modelling. Creating the wireframes is a time-consuming process, requiring reasonable software skills, patience and an eye for detail. The interpretations can be subjective; indeed, even the same geologist will give different shapes if presented with the same data at different times. The process can become particularly tedious when trying to carry out updates due to new data. It can also be difficult to test the effect of alternative interpretations or grade thresholds because of the time constraints in production.There are now several implicit modelling tools available, either as standalone programs or as add-on modules to existing GMP. In this paper, the authors develop a workflow using implicit modelling methods to show how grades and geology can be rapidly interpreted to provide effective domains for grade estimation. The paper includes case studies from open pit gold mines. The implicit modelling approach can save several days of interpretation work for each grade control drilling campaign.CITATION:Rose, S and Ireland, J, 2014. Implicit modelling applied to grade control data, in Proceedings Ninth International Mining Geology Conference 2014 , pp 115–122 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

Management of Mining Wastes in European Union and Developments in Turkey

Sep 13, 2010

By G J. Corbett, T M. Leach

Although hosted within an Ordovician magmatic arc, the Peak Hill high sulphidation system displays features typical of youngerPacific Rim high sulphidation epithermal gold deposits. Regional NW trending transfer structures are inferred to localise the magmatic source at their intersection of the NS trending arc. Fluids have migrated from the magmatic source along NW structures and thence exploited permeable horizons, which have become silicified. Alteration displays typical zonation from silicification through assemblages characterised by alunite, pyrophyllite and kaolinite and is followed by breccia/fracture controlled sulphide and gold deposition. Sinistral rotation on the NS arc has dilated NW trending fractures to produce the WNW to EW dilational fractures which host the higher grade ore. Mineral assemblages are typical of formation distal to the magmatic source in an epithermal environment. The combination of alteration and mineralisation zonation with structure provide fluid vectors which target a magmatic source to the SE of Peak Hill.

Jan 1, 1995

By Morrell S

As more and more autogenous and semi-autogenous mills are run in closed circuit with cyclones the limitations that can be imposed by poor grate and pulp lifter design are becoming increasingly apparent. Relevant literature on the subject is al

Jan 1, 1997

I have spent most of the past 35 years working as an economic geologist in the area of exploration and development of base and precious metals. Most of this period has been as an employee of Trans-National-Corporations (TNC's). I presently act as a consulting geologist to a joint venture company, bringing together two such TNC's: Anglo American Corporation and affiliated companies De Beers (Diamonds) and Minorco (Metals mining outside of Southern Africa), and Normandy Mining Limited ofAustralia. Normandy is presently through its gold arm PosGold, Australia's largest gold miner and Anglo American can claim to be the world's largest gold company producing over 280 tonnes of gold a year, more than twice its nearest rival Gold Fields of South Africa. In addressing this topic, the role that Government can, and should play in mineral development, I will be drawing heavily on some examples from these and other TNC's experience in recent offshore mining investment.

Jan 1, 1995