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By J Harris, J Li, M Shi, P A. Kirsch, D Sprott

Australia has an enviable global reputation as a leader in health and safety outcomes in the hazardous industry of mining, in part due to an increased application of risk management regarding operational planning and mining practice. In 2010, the Australian Coal Association Research Program (ACARP) initiated a major project, RISKGATE, to build, capture and deliver a national body of knowledge to assist companies with the management of risk in coal mining. The online system contains information for tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives underground, explosives open cut, manual tasks, slips/trips/falls, outbursts, coal bumps and bursts, human–machine interface, tailings dams, occupational hygiene and inrush. In 2014, RISKGATE is developing content for fitness for work (fatigue, drugs, alcohol, physical well-being, psychosocial well-being).This paper analyses underground mining fatalities in Australia and the United States since 2002 and introduces RISKGATE with a focus on the knowledge base for management of hazards in underground operations. Through capturing coal industry expert operational knowledge, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover within the mining industry. This coal-based body of knowledge is a platform that can be evaluated and implemented for other mining domains and high-risk industries within the energy supply chain.CITATION:Kirsch, P A, Shi, M, Harris, J, Li, J and Sprott, D, 2014. RISKGATE and underground operations, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 11–18 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By L L. Kuhar

The AMIRA International P843A Geometallurgical Mapping and Mine Modelling (GeMIII) project is an interdisciplinary research collaboration between 17 global mineral companies and four research organisations aimed at providing support for the emerging industry trend of geometallurgy. The main aim of the project is to develop predictive geometallurgical indices which can be incorporated into a resource block model to maximise the commercial value of an orebody and to minimise the social and environmental impact of mining operations.Researchers at the Parker Centre/CSIRO have been focusing on the development of predictive hydrometallurgical indices for the GeMIII project via rapid, small-scale, cost-effective tests and protocols for comparative ranking of attributes relevant to leach performance. The focus of the small-scale leach tests has been to determine the leach index (relative indication of leach performance), recovery, impurity deportment, reagent consumption, effect of size/degree of liberation and mineralogy of samples for their relative ranking. Predictive tests for heap leach hydrology (related to agglomerate characteristics) and slurry rheological behaviour are also being developed.

Sep 5, 2011

By Hare S. M, Lumsdaine I, O&apos

Converter slag assaying 3.7 per cent Cu is produced by Mount Isa copper smelter at a rate of up to 180 000 tonnes per annum.Priority is given to the processing of ore, however concentrator capacity periodically exceeds that of the mine and the opportunity is taken to treat converter slag. It is processed in batch campaigns, typically through the Copper Concentrator, but the Hilton Concentrator has also been used. Slag and ore are kept as separate as possible, since each has an adverse effect on the flotation performance of the other.

Jan 1, 1993

By J Skousen, C E. Zipper

"Prior to the 1950s in the USA, surface coalmines were generally left without any reclamation. As government regulations advanced, mine operators were required to backfill the area and plant grasses or trees. After the federal Surface Mining Control and Reclamation Act (SMCRA) was passed in 1977 in the USA, mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after the mining. Common post-mining land uses in the USA are: agricultural uses such as prime farmland reclamation with crops, hayland and pasture, and biofuel crops forestry wildlife habitat building site development.Provisions and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were established. Post-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future.CITATION:Skousen, J and Zipper, C?E,?2014. Post-mining land use options in the Appalachian coal mining region of the USA, in Proceedings Life-of-Mine 2014, pp 153–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

By V Rimal, d M. Tangstad

Multiphase slags form the basis of the reduction pathway for manganese ferroalloy production. The present work aims to understand the flow of slag through the coke bed based on experimentation in controlled conditions. Synthetic slags of different basicities were evaluated for their phase composition, viscosity, and flow. The two-phase slag will have two zones: a liquid slag zone and a multiphase zone. The multiphase zone will consist mostly of a solid phase with some liquid slag between the solid particles. The multiphase part will hence have a high viscosity. The liquid zone will flow into the coke bed while the multiphase area will stay. With increasing reduction, the multiphase area will decrease in size until the solid phase is gone and the whole slag will flow into the coke bed. The effective viscosity of slag will decrease with the lowering of the solid oxide phase. The results from flow experiments confirmed that the segregation of phases occurs when slag flows through the coke bed. It is observed that the flow is dependent both on the size of the void and the viscosity of slag.

Aug 21, 2024

By E Garbarino, P Molina, V Badino

Given the ever increasing quantity of construction and demolition waste (C&DW), one of the most challenging issues presently facing policymakers and public administrators in Italy concerns how to organise and manage collection and recycling and to understand whether and to what extent recycled aggregate can complement natural building aggregates in a sustainable supply mix (SSM). The paper presents the results of a research aimed at analysing energy and environmental implications of the C&DW recycling chain in the administrative territory of Provincia di Torino in northern Italy. In respect of a population of about 2.25 million inhabitants, the annual production of C&DW in the area under study is 1.8 Mt. A combined geographical information system (GIS) and Life Cycle Assessment (LCA) model was developed, paying attention to the geographical location, land use, transportation network and avoided landfill: crucial issues for sustainable planning and management. Around 90 recycling plants were classified according to the size, typology (stationary, semi-mobile and mobile) and physical- mechanical characteristics of the recycled aggregate. Under different assumptions relevant to the delivery distance, and considering the typology and grade of recycled aggregate, as well as local availability of natural aggregates, it was possible to evaluate the geographical coverage of aggregates demand and to use LCA in order to identify and quantify energy and environmental indicators.

Jan 1, 2009

By C R. Fountain, W R. Cannings

The zinc-lead-silver mineral resource at Lady Loretta ranks amongst the worldÆs richest when measured in terms of in situ metal grades. However, the project remains undeveloped 28 years after its discovery in 1969. The primary obstacle to development has been the fine and complex grain structure of its ores, which make flotation concentration inefficient even with fine grinding. The size and remote location of the deposit have also hindered exploitation. BUKA planned to directly fume the volatile target metals from the ore when it acquired the project. Intensive, post-acquisition modeling showed the innovative processing route to be uneconomic, notwithstanding high metals recovery and low waste content in fume product. Progressive modifications and supplements to the underlying fuming process enhanced economics and resulted in a new mine-to-metal processing route for zinc-lead-silver ores. The proprietary, three-stage BUKA Zinc Process offers technical, economic and environmental advantages. It is expected to find widespread application in the treatment of ores and residues. However, neither continued R&D nor application to Lady LorettaÆs currently delineated resource can be justified under prevailing market conditions. The objectives and results of each step in the process development sequence are outlined with reference to their impact on the commercial viability of the Lady Loretta project.

Jan 1, 1998

By H S. Mitri, A Sainoki

Destress blasting techniques have been widely employed in underground mines for the purpose of preconditioning highly stressed rock mass. Appropriate applications of the technique successfully contribute to increasing mine safety (eg mitigating the risks for rock bursts). This paper presents a simulation technique to estimate the extent of damage zones induced by destress blasting. A 3D numerical model with a single blasthole is constructed with FLAC3D code, whereby static analysis is carried out in which horizontal and vertical stresses are applied to the model in order to simulate stress conditions in a deep underground mine. Afterwards, dynamic analysis is performed whilst applying time-varying blast pressure along the blasthole. The blast pressure profile takes into consideration an instantaneous increase and gradual decrease in blast pressure as well as the propagation of detonation along the blasthole. In this paper, constitutive models allowing for shear and tensile strengths of rock mass that are dependent upon strain rate are newly implemented into FLAC3D code with C++ programming language, whereby blast-induced damage is assessed by the extent of tensile and shear failure zones. The results obtained from the dynamic analysis show significant decrease in the extent of yielding zones induced by destress blasting with increasing the magnitude of in situ stress. They indicate that considering in situ stress state is indispensable in order to propose proper blast design for each level in underground mines. Based on these results, the relationship between the extent of the damage zone and depth at which destress blasting is performed is established. Furthermore, stress dissipation induced by destress blasting is examined with static analyses, in which the modulus of elasticity is decreased according to a rock fragmentation factor, a, only for the area where tensile and shear failures takes place during the dynamic analyses. A model parametrical study with respect to a is undertaken. The relationship between the rock fragmentation factor and the stress dissipation in the yielding zones is developed from the parametrical study. The developed relationship can be useful when destress blasting is designed for massive rock masses.CITATION:Sainoki, A and Mitri, H S, 2015. Simulation of damage zones induced by destress blasting, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 245–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M I. Pownceby, A Guiraud, S Purohit

Sticking and breakage of iron ore pellets during high temperature reduction can result in several operational challenges during shaft furnace ironmaking. With the shift to H2-based DRI processes and decreasing iron ore quality, this issue becomes more prominent. It is therefore important to understand how the iron ore chemistry and mineralogy affects the sticking and breakage of pellets inside the shaft furnace. This study provides a review of the mechanisms that lead to sticking and breakage of pellets inside the shaft furnace. The sticking index of pellets is related to the rate of metallic iron production as well as the precipitation morphology of product iron. Sticking of pellets is also enhanced by the formation of low-melting slag phases. The breakage of pellets inside the shaft furnace is often associated with the mechanical load of burden and pellet swelling, which is caused due to iron whisker or protruded iron formation. This paper investigates how the composition of iron ore, particularly the presence of different impurity oxides such as SiO2, Al2O3, MgO, CaO and alkali oxides in the pellets, influences the sticking and swelling indices. The effect of ore mineralogy on these adverse behaviours is also discussed.

Sep 18, 2023

By E A. G Marques, P M. Dight, T A. V Costa, K Mercer

Brazilian banded iron formation (BIF), known as ‘itabirite’, is the main host rock for iron ore in the Iron Quadrangle mines, Brazil. Their geneses are controversial and it is agreed that diagenetic, metamorphic and tectonic events, as well as weathering processes, were responsible for the iron concentration. In addition, it is understood that weathering processes are mainly responsible for reducing the original high intact rock strength, and for generating deep weathered profiles with low strength rocks commonly observed in Vale’s mines.A considerable amount of work has been done to correlate the macro and micro aspects of the itabirites as physical, chemical and geotechnical characteristics that directly or indirectly affect the intact rock strength; however, it is not yet clearly understood what effects the weathering processes have on the strength reduction of these rocks and its associated impact on pit slope stability. This forms a key focus of the lead author’s current research work.This paper presents a review of the geological, geotechnical and weathering characteristics of the itabirites, and early results for the evaluations of fresh itabirites from the PhD thesis research being undertaken by the authors at the Australian Centre for Geomechanics, School of Civil, Environmental and Mining Engineering, The University of Western Australia, sponsored by Vale SA.The results showed that to evaluate the density and unconfined compressive strength (UCS) correlation, not only the porosity but also the geological features should be considered, as they are responsible for data dispersion; however, the presented data suggested a trend that provides the confidence to develop advanced studies and a data population increment to establish proper correlations to support a reliable UCS method.CITATION:Costa, T A V, Dight, P M, Mercer, K and Marques, E A G, 2015. An overview of the weathering process, preliminary density and unconfined compressive strength correlations for fresh itabirites in vale mines on the western side of the Iron Quadrangle, Brazil, in Proceedings Iron Ore 2015, pp 241–254 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By S L. Barbour

Measurement of the net percolation from the base of a cover system into the underlying waste material is a key component of a cover system monitoring program. The units of measure (ie a percentage of precipitation or rainfall) are simple to understand for all stakeholders, which increases the importance of obtaining representative net percolation values. In general, lysimeters are used to measure net percolation across the cover material-waste material interface; however, the design of lysimeters for cover system monitoring programs in the mining industry have typically not considered fundamental aspects of lysimeter design. Lysimeter design is typically thought of as being conceptually simple, when in reality the design, installation, and operation of lysimeters is often counter-intuitive, due to the complexities of flow through unsaturated soil systems. This paper puts forward a methodology for lysimeter design while also presenting the fundamental design variables that should be considered. Lysimeter design for differing climates, cover materials, and waste materials is discussed. Finally, the performance of lysimeter designs previously installed in the field at sites in Australia, Canada, and the United States are subjected to numerical modelling to determine whether net percolation is being measured properly.

Jan 1, 2003

By Ueki S

Underground coal gasification (UCG) is a promising process for obtai- ning energy from coal, which is either unmineable with current mining techno- logy or uneconomic to recover, using conventional methods, in the present energy market situation. There are several coal fields, which could become new coal reserves, if the UCG process were successfully applied. In the 1960's Japanese researchers made a number of basic studies and field tests into UCG, although not all of them produced favourable results. This paper reviews Japanese research on UCG. This includs basic studies into coal gasification using a small, tube reactor fed by air and oxygen, and also large scale model stu- dies(reactor size of 8.Om x 2.4m x 1.5 m). Field test results from Akabira colliery in Hokkaido and a feasibility study of power generation using UCG from a coal field in Hokkaido are also Presented.

Jan 1, 1987

The City of KalgoorlieBoulder is situated approximately 600 kilometres to the east of Perth, and as the major regional centre of the Eastern Goldfields, supporting a population of approximately 25 000. The formation of Kalgoorlie Consolidated Gold Mines in 1989 brought the existing operating entities adjacent to the city under common ownership and management. The Joint Venturers forming the management company are Homestake Gold of Australia and Gold Mines of Kalgoorlie (a Normandy/Poseidon company).This traditional underground mining centre has been worked since 1893, yielding 40.5 million ounces of gold ore with an average head grade of TEN grams per tonne. Historically the heart of the operation has been the famous Golden We located on the Eastern perimeter of the city, in the area known as Fimiston. The other significant operations that form KCGM are the Mt Percy Open Pit and the Mt Charlotte Underground Operation.

Jan 1, 1992

Chlorine as a lixiviant for gold possesses a number of significant chemical and Idnetic advantages over cyanide but because of its corrosive and vaporous nature the method of implementation needs to be significantly modified. At comparable reagent concentrations the dissolution rate for gold in the C12/Cl- systems is some 10 - 100 times that achieved in the 02/CN system. The dissolution rate in the chlorine system is largely a function of the concentration of C12, Cl- and pH. Under conditions of low Cl', (less than 50 g/1), the dissolution rate begins to drop off dramatically over the pH range from 3 - 4. Increasing the level of dissolved chloride ions shifts the pH of this rate reduction to around pH 5 at 100 g/l NaCl, and to around pH 6 at 300 g/l NaCl.

Jan 1, 1991

By Bhattacharyya A. K

The current methods for predicting pillar strengths are reviewed. A two-dimensional model, based on the Mohr-Coulomb failure criterion, is proposed for determining the compressive strength across the width of a long pillar. The model can be used to determine pillar strength and the depth of the crushed (ie yielding) zone from the pillar edges. The values of the parameters in the model, namely the cohesion and internal friction angle of the coal seam, friction angles at the contact of the coal seam with the roof and floor are determined by matching the strengths predicted by this model with the Bieniawski pillar strength formula for pillar width to height ratios up to 5. It is found that the derived values of these parameters are quite close to the results from laboratory tests. Based on the model, a preliminary analysis of pillar stability is made.

Jan 1, 1995

By Daoust G, Dubois JF

The optimal sequence of decisions on rates of production and cutoff grades is obtained by a dynamic programming model. The main parameters are : 1. the size of the deposit, average grades and grade distributions, 2. the operating costs of mining and concentration, 3. the investments in mine and mill, 4. the smelter charge, 5. the price(s) of the metal, 6. the recovery and the grade of the concentrate, 7. the rate of interest, 8. the taxation formulae, 9. the upper limit to rate and the rate interval and 10. the upper and lower limits to cutoff and the cutoff interval. An amount of ore can be mined at various rates while applying various cutoff grades. It is assumed that a decision to mine at a certain rate during a period conducts to a certain state regardless of the cutoff grade. This assumption which is valid for several

Jan 1, 1977

By White A, Price G

The main assets of a mining company are its orebodies; the second are the people who find and use them.The graphs in Figure 1 were derived from a paper by Rob Macdonald of Rothschild Australia presented to The AusIMM Centenary Conference in Adelaide earlier this year. They show that the value of the industry on the Australian Stock Exchange halved over the past decade, despite the re-investment of capital equivalent to its full market capitalisation. Why is this so? The average dividend yields for the ASX Mining Index was never above five per cent during that period and barely averaged 2.5 per cent. Why then is $Ai million capital re-investment per employee since 1960 not enough to generate a rate of return to investors better than lousy bank interest? Do the investing public no longer regard our industry's assets to be world class?

Jan 1, 1993

By Scott B. R

Bougainville's copper mine is located on the west slope of the Crown Prince Range on Bougainville. A high grade copper concentrate is produced for sale to overseas customers. Production planning which was originally based on pilot plant data has developed progressively since commissioning of the concentrator in 1972. Pilot plant data and mine sampling have been supplanted by the correlation of concentrator performance with ore sources, as the basis for short term planning. The influence of accurate sampling is reflected in 1. hourly shift control, 2. the daily milling statement, 3. the prediction of the characteristics of ore from various mine locations, 4. production reconciliation, and 5. the control of copper losses. The mechanical and electrical failures of the original sampling system emphasized the need for a reliable, automatic sampling facility. The development of a pneumatic drive mechanism, which has now been fully field tested, was undertaken.

Jan 1, 1976

By Ellyett C. D

This paper is an appraisal of the application of optical-mechanical-scanners operating in the non-photographic infrared wavelengths (3-5 and 8-14 micrometres) to mineral exploration in Australia. Pundamental principles of the operation of airborne scanners and their data output, thermal infrared (IR) imagery, are summarized. It is contended that thermal IR imagery often depicts the distribution of electromagnetic radiation emitted from earth surface materials better than aerial photographic techniques because optical-mechanical-scanners sample wavebands which straddle the wavelength peak of earth surface emission. To illustrate the geological features which such scanners can depict, reference is made to thermal IR imagery of a number of areas in Australia where the technique has been applied for exploration purposes. The images demonstrate that this technique can detect structural features like faults and folds, stratigraphic data by distinguishing different rock types and delineating their

Jan 1, 1973

By Ryan CG, Both RA, Mernagh TP, Large RR, Hunns SR, Gemmell JB

The Hellyer and Mt. Chalmers deposits are mound-style volcanic-hosted massive sulphide (VHMS) deposits in Australia. Textural, petrographic and microthermometric investigations of fluid inclusions in the Hellyer stringer system indicate that Type I, primary, liquid-vapour inclusions are 10-15 pm in size, and yield homogenisation temperatures of 170-220¦C in early 2A veins, 165-322¦C in main-stage 2B veins and 190-256¦C in late-stage 2C veins. These data suggest a waxing and waning thermal history. However, the average salinity remained between 8-11 NaCl equiv. wt % in all Stage 2 veins. At Mt. Chalmers, Type I inclusions up to 20 ¦m are found in quartz from the mineralised zone, and these inclusions yielded homogenisation temperatures of 160-268¦C and salinities of 5-8 NaCl equiv. wt %. Laser Raman spectroscopic (LRS) analysis indicates the presence of CO2 (

Jan 1, 1995