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By C Adams

Reports of delays and cost blowouts in major study and construction projects are becoming increasingly prevalent in the resources industry. This is mainly being attributed to an escalating cost environment associated with the increased number of projects in the development to construction pipeline and a scarcity of competent skilled resources to deliver these projects. However, not all this effect can be directly attributed to the current environment. Historically the mining industry has not performed well in its ability to deliver projects according to the financial and physical parameters forecast in the feasibility study process. To manage the risks associated with delivery of major projects, resource companies need to ensure they use a standardised approach to management of their project development to satisfy project objectives and enable more efficient use of the increasingly limited available resources. Each discrete step in advancing the project from scoping study to operations needs to be integrated, reducing the amount of rework and duplication. This paper is primarily a consolidation of existing ideas on project management systems but also introduces new concepts to solve current issues. It describes the basic components of a typical mining project, the issues that commonly arise, the key attributes, and critical steps required for an effective integrated project management system covering projects from initial scoping studies through to project commissioning and operation. This paper focuses on technical study components of the mine development project with allowance for transitioning to design and construction and operation phases.

Jan 1, 2006

By P Steinier

Most operations, when considering their comminution circuit, are primarily concerned with achieving the desired particle size distribution to obtain adequate liberation for the separation process, at minimum cost. Invariably, the effect the grinding media has on the subsequent separation process (ie flotation, leaching) is not taken into account when selecting the media. This choice is driven by cost rather than metallurgical outcomes. Maximising valuable mineral recovery, with optimum selectivity against gangue minerals, is about good particle preparation. And, particle preparation is strongly related to achieving adequate mineral liberation with the correct pulp chemical conditions. However, the pulp chemistry of a system is largely ignored and relies heavily on pH control and the addition of appropriate reagents (collectors, frothers, activators, depressants). The changes effected by the addition of the various reagents are obtained through conditioning the ground pulp prior to or during the concentration stage, subsequent to grinding. Frequently, reagents are added during grinding with good effect, but the impact of the grinding media on down stream processing is usually overlooked. A number of case studies examining the effect of grinding media on pulp chemistry and subsequent flotation performance were completed on several different sulfide mineral systems (for example, lead/zinc, copper, refractory gold). The evidence suggests that a change in grinding media type from forged to high chrome (ie conditioning the pulp during grinding) resulted in a shift in pulp Eh to less reducing conditions, an increase in the dissolved oxygen content of the pulp and a reduction in the iron species present. The changes have a positive impact on flotation behaviour. The results of the case studies are discussed.

Jan 1, 2004

Ferruginous manganese deposits have been known at Ripon Hills since the late 1950s. The main group of deposits occur in an area 6 km by 5 km and these were extensively investigated by Longreach Metals N.L. during1971 and 1972 for possible commercial exploitation.Ripon Hills is a dissectcd fault plateau 350 m above sea level formed by the uplift of a block of gently dipping Proterozoic shales, cherts, and dolomite. The plateau consists of chert breccia which is underlain by massive dolomite. The shales which are ferruginous and manganiferous overlie the chert breccia but are now only preserved, in places, in the broad depression and valleys of the plateau.The ore deposits occur as supergene replacement of the shales and were investigated by geological mapping, grid percussion and diamond drilling, and bulk beneficiation testing. Iron and manganese oxides erraticallyreplace Shale accompanied by the leaching of other minerals. The ore is composed of fine grained pyrolusite intergrown with fine grained hematite and locally containing extensively altered bixbyite and braunite. Thegangue mineral is mainly kaolin.The average grade, using a 15 per cent Mn cutoff, was 19 4 per cent Mn and 25·9 per cent Fe for a combined drill-proven, indicated, and inferred tonnage of 56,000,000 tonnes. The average depth of this mineralization from the surface is 11 m. Using a cutoff grade of 20 per cent Mn the average grade was 24·6 per cent Mn and 23·0 per cent Fe for a combined tonnage of 12,000,000 tonnes to an average depth of 8 m.The substantial drop in reserves occurs because a high proportion of the mineralized material contains less than 20 per cent Mn.It was shown that whereas the lower grade ore, despite erratic fluctuations in grade, could be beneficiated to specification grade by crushing, screening, and conductivity ore sorting, the higher grade ore could be beneficiatedto specification grade by crushing and screening only. The utilization of the higher grade ore was considered to constitute a more viable operation.There is potential for high grade manganese ore to be discovered in the Ripon Hills area at the contact of chert breccia and underlying dolomite.

Jan 1, 1977

Geometallurgical Study of Copper Oxide Mineralisation Hosted in Gravels of Different Physical Quality

Sep 13, 2010

Mount Isa Mines Limited first installed electronic data processing equipment in 1959. The decision to replace this equipment with a computer was motivated by the need for greater processing power and the availability of new and less expensive computers. Consideration of hardware software and delivery features of available equipment, resulted in the selectIon of an ICT 1900 series computer which was installed in March 1966. Special air-conditioning and power stabilization equipment was also required.Systems design and programming was carried out by personnel recruited from within the Company and trained by the computer manufacturer. Early work was hindered by the problems of remote location.Initial applications were basically accounting functions whIch were taken over from the EDP installation. Subsequently computer applIcatIOns of a more complex technical nature have been undertaken. Future work will include both "scientific" and data processing applications.

Jan 1, 1968

By R Lewis

Drill hole magnetometric resistivity (DHMMR) is a relatively recent addition to the explorationistsÆ suite of techniques for finding further resources in the vicinity of a drill hole. The method relies on gathering of an applied current into zones which are less resistive than the country rocks and it was first applied to exploration programs looking for weakly conductive sulphides, such as, for example, carbonate-hosted zinc deposits. More recently, it has been applied to a wider range of deposit styles, including highly conductive nickel sulphides. It has been found that the technique is capable of not only detecting mineralisation not seen by conventional electromagnetic (EM) techniques, but it can detect at a greater distance. Also, whilst EM is superior at defining tabular-shaped conductors, DHMMR may be more effective at finding cigar shaped sulphides. This paper presents a number of examples illustrating these findings.

Jan 1, 2000

By Tumilty JA, Schmidt CG

Sulphide ion is a powerful poison in gold cyanidation, however, the detrimental effect is less severe in plant practice. This is thought to be due to the presence of depassivating elements in the ore, mainly lead. Trace amounts of lead can counteract the poisonous effect of considerable amounts of sulphide. The reaction is instantaneous and is likely to be a direct involvement in the electrochemical surface reaction. Lead addition cannot be regarded as an all-round cure when experiencing poor leach efficiencies. A possible beneficial effect depends on the mineralogy of the ore and has to be determined individually for every material.

Jan 1, 1989

By L Dixon, J Carter, K Auyong

Fourier transform infrared (FTIR) spectroscopy and other near infrared (NIR) tools have been used in the bauxite industry for many years. Infrared spectroscopy exploits the differences in chemical composition and lattice structure to produce a characteristic response. Spectral devices, such as those from ASD Inc and the HyLoggerTM, provide qualitative mineralogical data targeted towards hydrated minerals detected in the near and short wave infrared region. The FTIR spectrum extends into the mid and thermal infrared range and can therefore respond to the presence of silicates and oxides, in addition to hydrates and carbonates.The key to successful utilisation of infrared spectra, however, is the interpretation methodology. In this study, FTIR spectra were calibrated against quantitative X-ray diffraction data for the determination of the mineralogy of iron ore. A full pattern profiling machine learning technique was utilised for the calibration, and the assessment of the regressions determined from an independent validation set. The abundance of key minerals – hematite, goethite, kaolinite and quartz – were determined and the results correlated against X-ray fluorescence assays and loss on ignition data. The results of the study indicate that spectral techniques using a full-pattern profiling machine learning approach and artificial neural networks can be used successfully to obtain objective and quantitative mineralogical data to support field observations and analytical results for iron ore resource modelling. A comparison of this technique to the cost, quality and timeliness of other quantitative mineralogy tools is also made.CITATION:Carter, J, Auyong, K and Dixon, L, 2017. Determination of iron ore mineralogy using Fourier transform infrared spectroscopy and machine learning, in Proceedings Iron Ore 2017, pp 519–528 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By E Westthorp

Final mine sealing of BMA’s Crinum North mine, near Emerald, Queensland was undertaken in December 2015. Due to the benign atmospheric environment at Crinum North, the Queensland Mines Rescue Service (QMRS) Górniczy Agregat Gasniczy (GAG) unit was utilised to reduce oxygen levels throughout the underground atmosphere as part of the final sealing process.The GAG was utilised by way of a vertical borehole from the surface to seam to successfully reduce oxygen levels throughout the underground mine workings. Application of the GAG unit enabled the underground mine to be classified as stable and inert within days of the GAG operation, and subsequently cease gas monitoring at Crinum North. The data and information obtained from this activity provides valuable information to the underground coal mining industry on successful application of the GAG in realistic situations.This paper discusses the strategy used for sealing, the assisted inertisation and the results obtained from the application of the GAG unit. It discusses both the overall results and gives a detailed review of the gas monitoring data obtained via the tube bundle and real-time system, both during and following the use of the GAG unit.Gas monitoring results obtained and the strategy used are critical to share with the industry to obtain a better understanding of how the GAG unit works, and how it can be applied for emergency preparedness, emergency response or planned inertisation.CITATION:Westthorp, E, 2017. A review of the strategy and gas monitoring results obtained during the use of Queensland Mines Rescue Service GAG unit at Crinum North mine, in Proceedings Australian Mine Vent Conference 2017, pp 309–318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By G T. Jemwa, F Rousseau, F J. Wolfaardt, J A. M Rademan, P W. Smit

Mining companies are increasingly faced with the challenge of reducing operating costs while maximising throughput and profitability. At the same time, the grade and quality of treated ores are becoming poorer and more variable, resulting in suboptimal process performance.It is now widely accepted that strategies to drive operational goals must revolve around improving plant availability, reliability and process efficiency. In particular, progress in plant automation and control systems has seen a trend towards unified frameworks for control and optimisation of mineral processing plants. These frameworks seek to seamlessly integrate different roles and tasks involved in process operations - IT, automation, plant maintenance and operations. An integrated solution framework for reducing process variability, increasing process efficiencies and maximising plant availability and reliability is discussed within the context of a typical milling circuit. The framework exploits a real-time analysis ægapÆ evident in production operations that prevents timeous identification of equipment and process failures. This is achieved by leveraging predictive analytics for equipment health monitoring, control loop monitoring and advanced regulatory control solutions towards enhanced process performance, improved asset management and regulatory compliance. The framework provides for early and actionable warnings on equipment and process degradation using real-time operational data.Resolving these problems can potentially avoid unplanned downtimes, process instabilities and other operational surprises, thus ensuring optimal plant throughput and optimal process behaviour for improved recoveries. Integrating control systems and plant automation with advanced analytics to analyse and optimise processes enables operations to achieve reductions in the variability of key process parameters. In addition, early detection of equipment malfunction or suboptimal process conditions leads to improved equipment availability and reliability. Ultimately, these operational gains reflect in profitability because of plant throughput and recovery gains. These benefits are demonstrated using data from a South African gold mining operation, where such an integrated asset and process health monitoring framework for process optimisation has been implemented.CITATION:Jemwa, G T, Wolfaardt, F J, Smit, P W, Rademan, J A M and Rousseau, F, 2013. Towards an integrated framework for asset and process health monitoring and optimisation on a milling circuit, in Proceedings World Gold 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Y Xiao, C Lei, C Shu, W Wang, K Wang, J Deng

To investigate the effect on coal spontaneous combustion with high geo-temperature, an experimental apparatus was developed to measure characteristic parameters of two kinds of coal samples at different temperatures: one was 40°C (G coal sample) and the other was a rising temperature from room temperature (C coal sample). Based on the relationship between CO concentration and the temperature variation, a calculation model of the apparent activation energy of coal was established. The results indicated that the oxygen consumption rate, the generation rate of CO and CO2, and heat release intensity of G coal sample were higher than C coal sample. This trend was more and more obvious as the temperature increased. Furthermore, the apparent activation energy of G coal sample was lower than C coal sample, especially at low temperature stage, which demonstrated that the more the oxidation and exothermic reaction of G coal sample was enhanced, the less energy was required to break the barrier of oxidation reaction. Under the same condition, the speed of oxidation reaction was faster for the coal in the high geo-temperature environment, which was more liable to spontaneous combustion.CITATION:Lei, C, Deng, J, Xiao, Y, Shu, C, Wang, K and Wang, W, 2017. The effect of high geo-temperature environment on spontaneous combustion – an experimental study, in Proceedings Australian Mine Vent Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By M Dickie

During the 1980s and early 1990s low cost gold treatment plants were at the forefront of the Australian engineering and mineral processing business. This opportunity was the result of a high gold price and innovative design by emerging engineering companies in an expanding market. The low cost approach to gold plant design and project execution resulted in smaller and shorter life projects becoming viable and the multiplicity and fast track approach of the projects resulted in sharp learning curves. From the mid 1990s to the early 2000s the relatively low commodity prices and resultant reduction in minerals opportunities also resulted in innovative design in both small and large plants, albeit on a reduced scale. The innovation was associated with alleviating capital cost pressures for large capacity low-grade (eg NewcrestÆs Cadia) or small-scale (eg JubileeÆs Cosmos) projects to either improve NPV or to enable the project to be won and profitable in the competitive lump sum environment. Between 2004 and 2008 the engineering market became less competitive from an engineerÆs perspective due to the high demand for engineering services in a high price commodity market. The need for innovation remained but was driven overtly by shortages in water, power and personnel and long equipment lead times. This paper discusses some of the factors that contribute to the capital cost of a project and the scope for improving the likelihood of financing and increasing the project net present value (NPV). Case studies with recent large copper concentrator projects will be used to demonstrate how a value driven approach to project and plant layout can result in significant improvement in NPV.

Jan 1, 2009

By G McCullough, J Bassan, d P. Knights, C T. Farrelly

By 2045, carbon-neutral mines will be economically producing products that are vital for the world’s transition to renewable energy. After overcoming significant technical challenges (and the investment of significant capital), leaders have successfully eliminated the use of diesel and other fossil fuels by introducing a wide range of new decarbonisation technologies. These leaders will be reaping the benefits of lower production costs (resulting from elimination of diesel), stable and predictable operations, and easier access to capital for their future projects. This paper describes a future scenario of how a net zero carbon and zero-entry mine could operate by taking maximum advantage of technologies in development or already proven in other industries. Some miners have been unsuccessful in their efforts to reach decarbonisation targets. Instead, they have been forced to close or offload their assets to be acquired by operators with better sustainability credentials, or, in some cases, to indigenous or community-based enterprises with vested interest in making operations viable and sustainable. Regardless of ownership structure, all successful mining operations will have fostered strong and positive community relations that bring education, health, security and economic development opportunities to the communities while respecting their traditions, land-uses and culture. As shallow, easy to mine deposits have become scarce, the majority of new mines are underground. Advancements in electric underground technology and the feasibility of ‘zero entry mining’ (with no personnel in active mining zones) has made it increasingly possible to economically operate underground mines, even at shallow depths. The newest mines have a near zero footprint on the surface, produce no harmful by-products, and are employing in-place or in situ methods of extraction that are efficient and low impact. Surface land-uses, such as agriculture and renewable energy generation, continue in the immediate vicinity of the mine, with no significant ground disturbance, community impact or environmental footprint.

Sep 1, 2024

By I Mason, A Wellington, J Hargreaves

Many people are familiar with the use of marine echo sounders which are used by fishermen to monitor water depth and locate schools of fish. Similar technology has recently been used in some West Australian mines to provide detailed maps of ore contacts and other geological structures. Whilst drillhole intersections provide details of the location of a contact at a point, echo sounding can be used to obtain a continuous profile of the contact. A series of profiles together with drillhole intersection data can be used to build a more accurate geological model than can be inferred from drillhole intersections alone. The benefits of this are more complete ore extraction, less dilution and the ability to make more informed financial decisions. This paper presents a case history which demonstrates the successful application of the technology.

Jan 1, 2000

In 1961, West Australian Petroleum's Eneabba No. 1 bore encountered 22 seams of coal totalling 40 ft in thickness between the depths of 6373 ft and 6441 ft. On analysis, this coal had a similar calorific value (8000-HOOO B.T.U./lb, assuming 20 per cent water) to the coal from the Collie Coalfield, Western Australia's only known area of commercially exploitable coal. Being buried to depths in excess of 6000 ft, the coal at Eneabba had developed weakly-coking properties, and thus, although much younger than the Permian coals of Collie, gave promise of being a major potential source of power for Western Australia.West Australian Petroleum undertook a programme of stratigraphic drilling and shallow test drilling to determine whether this coalhorizon persisted into the outcrop of the Lower Jurassic sediments in the Hill River district, 140 miles NNW. of Perth, and, if it was present, if the quality and quantity of the coal would warrant development of the deposits by open cutting. The coal horizon was identified in the near surface, but the poor quality of the coal and the complexity of the structure made development (in the area examined) uneconomic at the time.A strong seismic reflection in the Eneabba area occurs at the same depth as the Jurassic coals. This event originates within the upper beds of the Lower Jurassic and it is probable that the velocity contrast between the higher velocity siltstones and the very low velocity coals enhances this very strong, distinctive seismic reflection.This event can be followed on continuous seismic data over a large area of the northern Perth Basin, from 13 miles SE. of Dongara to 20 miles SW. of Coorow. It can be followed from a depth of 4000 ftnear Dongara to over 17,000 ft to the SE., so development of thisvast potential source of power will depend on the economics ofprocesses being developed for the production of power from theburning of coal seams in situ.INTRODUCTIONThe discovery of 22 seams of economically useable coaltotalling 40 ft in thickness in the Lower J urassic sedimentsof the Eneabba No. 1 bore (Fig. 1) led to the search forthese seams at economically workable depths. The Ministerfor Mines in Western Australia granted to West Australian1. Supervising Geologist, West Australian Petroleum Pty. Ltd.Manuscript received at The Institute, 25th May, 1964. and presented to the 1964Annual Conference.

Jan 1, 1964

The polymerisation of silica is found to interfere with thickening of leach pulps at Risdon. Hydroxyl ion and fluoride ion are catalysts for this reaction. Stability may be obtained by the presence of aluminium or ferric iron.INTRODUCTIONAt Risdon it has been a matter for satisfaction that, although the concentration, of silica in leach solutions is appreciable, it has ,given relatively little cause for anxiety.However the margin of safety is small and some intermittent difficulty in thickening leach residues during the last few years has prompted a further investigation, certain parts of which are described here since they may be of general interest.Leaching and ClassificationThe method of leaching which is practised at Risdon has been described in, two previous articles, by W. C. Snow (1936) and S. W. Ross (1949) to whiCh the reader is referred for detail. Continuous leaching is practised, the circuit solution flowing through five air agitated pachucas in series, to tlie first of which calcine is added. The circuit solution, which also enters the first pachuca, consists of spent electrolyte from, the electrolytic cells and contains 90 -gm. of free sulphuric acid per litre. About 80 per cent of the solublezinc oxide is extracted from the calcine in the first pachuca, at a pH value of 1-1 (7 gm.H2S04/1 at 55 to 60°C. In the later pachucas the leaching rate decreases sharply. The leach pulp which leaves the 'last pachuca contains an average of 17 gm. of free acid per litre, corresponding to a pH of 1.7; but, owing to variations in extraction, the end point fluctuates between 2.5 and 0·3 gm. free acid per litre (pH:> 1·5 to 2.5). The average flow through the plant is 1,250,000 gallons per day, which corresponds to a production of 300...

Jan 1, 1958

In the past decade several significant intrusion-related gold deposits have been discovered in terranes historically exploited for tin-tungsten mineralization (eg Tintina Gold Province, Yukon and Alaska, Tasman Fold Belt, Australia and the Altaid orogenic collage in central Eurasia). This paper presents new data on the geological and geochemical characteristics of these deposits that links them to magmatic-hydrothermal processes and highlights their implications for exploration. New data from several intrusion-related gold provinces suggest that these deposits are found in areas that contain granodiorite to granite, but with a locally significant mafic component, have Rb/Sr ratios ranging between 0.1 and 1.0, and are moderately reduced (Fe2O3/FeO ~ 0.1 to 0.6) ilmenite series, metaluminous, I-types. The intrusions are distinct from porphyry copper intrusions and tin granites, but are more akin to tungsten granites. Hydrothermal fluid types vary with depth of emplacement in intrusion-related gold deposits and new proton induced X-ray emission (PIXE) data from syn-ore fluid inclusions in shallow and deep deposits provide fascinating insight into the variation in metal content between the different settings consistent with observed deposit metal associations. Exploration for intrusion-related gold deposits in tintungsten terranes should focus on regions that contain both mafic and felsic intrusion that are moderately reduced, metaluminous, I-type granites rather than terranes with dominantly highly fractionated, strongly reduced, peraluminous S-types. Intrusion-related gold systems occur in variety of deposit styles (in part controlled by host rock, proximity to granite, and depth of emplacement) and exploration geologists need to be aware of the variety of target types in and around the intrusive environment, and be able to recognise whether they are exploring a shallow or deep intrusion-related gold setting.

Jan 1, 2005

By C Doblin

Any value addition to the mineral sands in the Murray Basin (Australia) will generate waste that needs to be disposed of safely. For example, conversion of ilmenite and synthetic rutile to titania (TiO2) pigment would generate large amounts of environmentally undesirable elements. Processing of U+Th containing zircon sands to zirconia or to higher purity zircon would generate a low-level radioactive waste. In this study it is proposed that one way to circumvent the waste problem could be to contain such waste in magnesium-based (Sorel) cements. Containment of waste in magnesium cements is an attractive idea especially for the mineral sand processing companies that could operate in the Murray Basin in the future, because the required magnesium oxide and magnesium chloride may be made cheaply from the saline waters encountered during mining operations. The magnesium cement production process is also far less energy intensive than the Portland cement production process. The results of this study indicate that mixing a waste stream with a slurry of magnesium cement before being discharged to the disposal area would contain the waste in a æconcrete-likeÆ structure, resistant to dispersion by wind and moderate rain. However, some loss of strength and increased leaching of impurities, Mg and Cl could take place in wet climate areas. Ongoing research is being concentrated to develop a new process for making water-resistant magnesium cement.

Jan 1, 2002

By Edwards A. B

A table concentrate obtained experimentally by the New Occidental Gold Mines N.L. has unusual interest on account of the presence in it of abundant coated or "black" gold. The concentrate was obtained from ore from the New Cobar mine, Cobar, New South Wales, by feeding the oversize product from a "Dorr Bowl classifier to a Card table.Its assay value was 129 oz. of gold and 52 oz. of silver per ton, yet practically no free gold could be seen on panning.When, however, the concentrate was digested in hydrochloric acid fine rusty gold could be obtained by panning.The following chemical analysis was carried out by the mining company on a similar sample of concentrate.

Jan 1, 1941

By Madgwick J. C

Powders prepared from the algae Gracilaria secundata, Ulva lactuca and Ecklonia radiatawere shown to provide sole nutritional support for microbial, microaerobic, biodegradation of low-grade manganese dioxide ore. G. secundata was the most effective bacterial nutrient giving 32 per cent recovery of Mn++, at an average rate of 63 mg Mn++/litre/day and a yield of 24 mg Mn++/g dry powder in microaerobic cultures containing 1.5 per cent (w/v)MnOz ore and 3per cent (w/v) powder over 14 days. Although G. secundata was approximately half as effective as molasses in supporting microbial decomposition ofMnOz, possible on-site growth ofthe alga could be economicaIIy more practical than transporting carbohydrate to a distant mine site.

Jan 1, 1987