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WMC Limited, owner/operator of Olympic Dam, the worldÆs largest underground uranium mine and the fourth largest underground copper mine has now completed an expansion that has been classed as a benchmark in the mining industry. To achieve a production increase from 3.4 to 9.25 Mtpa from an underground mining operation in two years was a major challenge, it was essential to review the overall materials handling system from æthe face to the stockpileÆ. The challenge was two-fold:How to deliver 30 000 tonne of ore per day to the processing plant, from a single underground mine? To provide the processing plant with a consistent metallurgical feed. This paper traces the transformation from the old to the new materials handling system at Olympic Dam.

Jan 1, 2000

By M Doran

The Olympic Dam mine utilises 1.1 m to 1.4 m diameter raise bores for generating the initial slot void for most production stopes. Slot raise bores generally span two development levels ranging from 30 m to 50 m in height. Raise bores are reamed upward and typically leave a cap of rock equivalent to two times the raise bore diameter on the drill level (minimum 3 m). This provides safe access over the cap for subsequent production activities. It is therefore critical to ensure robust falling object protection for personnel accessing underneath, and in the vicinity of the raise bore void on the lower level. Recently, a number of mesh failures have occurred at Olympic Dam as a result of falling rock from the underside of the cap and raise walls. In addition, as Olympic Dam transitions to deeper and more challenging ground conditions, rockfall-off onto the raise bore protection mesh is anticipated to increase in frequency. This paper discusses the evolution of raise bore protection mesh used at Olympic Dam and presents results from recent site-based drop testing. This impact testing was carried out using a built for purpose object to replicate point loading and shear failure of mesh wires. Testing was also carried out on an improved mesh design which utilises two layers of Geobrugg high-tensile MINAX mesh. Results from the drop testing suggest an improvement in performance of the raise bore protection mesh is realised with the updated design.

Mar 29, 2023

By S Udayakumar, S Biswal, N Sarmadi, V Sahajwalla, F Pahlevani

Recent times have witnessed a notable momentum in the interest surrounding technology dedicated to harnessing waste as valuable resources, prompted by the mounting challenges posed by waste accumulation and the swift depletion of natural resources. The carbon dissolution process within a molten iron bath stands as a pivotal reaction within the metal processing sector. The current study explores the utilisation of waste graphite electrodes (WGE) (obtained after being utilised in an electric arc furnace) as a secondary resource of carbon for dissolution into liquid iron. Experimental investigations were carried out at 1550°C using the sessile drop approach. High purity iron powder was used and the carbonaceous substrates were prepared from the ground WGE. The carbon pickup was determined using a suitable carbon analyser. Furthermore, an examination of the interfacial area between the molten iron and the WGE substrate was conducted beneath the metallic droplet, which effectively represents the iron/carbon interface. This interfacial analysis was carried out on two different samples obtained after a varying period of heat treatments at 1550°C. The interface layer was investigated using scanning electron microscopy (SEM) in conjunction with energy-dispersive X-ray spectroscopy (EDS).

Jun 19, 2024

By B Tadesse, L G. Dyer, B Albijanic, M Jung

The presence of high concentrations of dissolved ions in groundwater, sea water or recycled water may alter the water structure, particle surface wettability and colloidal interactions between bubbles and particles and can have a significant effect on mineral flotation. While the impact of water quality on the flotation of precious and base metal minerals is well established, no relevant published study exists currently regarding the effect of water salinity on the flotation of rare earth bearing minerals. This paper attempts to quantify the effect of water quality variation on flotation recovery and grade of rare earth minerals and gain an understanding on which ions existing in saline water affect flotation behaviour. Specifically, it is aimed at investigating the effects of water quality on the flotation of monazite in the presence of cations such as Ca2+, Mg2+, K+, and Na+. Flotation tests, zeta potential measurements, and adsorption tests were performed to explain the flotation behaviour. It was found that monovalent ions such as Na+ and K+ have negative impact on rare earth minerals recovery and grade. The result of single mineral flotation tests showed that the floatability of monazite was significantly depressed in the presence of Ca2+ and Mg2+. The result of single mineral flotation test showed varying depression levels in the presence ions in the order of Ca2+ > Mg2+ > Na ~ K.

Aug 24, 2022

By S Maritsa, D Simbi, E K. Chiwandika, S M. Masuka

The steel industry is facing challenges on a global scale that include depletion of resources, huge energy consumption, and the emission of CO2. The demand for iron products is increasing due to the increased infrastructural development. Zimbabwe produced cast iron from scrap metals. However, there is currently a shortage of scrap, and yet Zimbabwe is rich in limonite ores that are currently being underutilised. The possibility of using limonite ore as a sustainable feed for pig iron production was investigated by preparing some limonite ore carbon composite pellets. The results showed that the addition of coal to the limonite ore and calcium carbonate mix to form the composite pellets resulted in a decrease in the drop number as well as the dry compressive strength of the composite pellets. This research aims to improve the physical properties of the green pellets by the careful addition of hydroxyethyl cellulose as a binder that was found to improve the physical properties of the green pellet. This is important for materials handling during the production process of the composite pellets. Results showed that the drop number was substantially improved by the addition of 0.4 wt per cent hydroxyethyl cellulose while the dry compression strength improved from 2.5 kg/pelIet to around 23 kg/pellet irrespective of the amount of binder added. The binder improved the physical strength of the iron-carbon composite pellets enough to allow for large-scale production of the pellets that can be an alternative and sustainable feed for cast iron production. However more results on the indurated compression strength and other properties such as the reduction degradation index, swelling index, and the reducibility test are required.

Jun 19, 2024

The Australian Mineral Industry has to compete on world markets, so its mineral research has to be aware of overseas developments, it must be of world class, and it must utilise as many ideas as possible in order to solve those problems that uniquely affect Australian minerals processing. North American mineral and resource research may be taken as a guide to world government, industrial, contract, and entrepreneurial research trends and ideas. A number of interesting findings are noted that may guide Australian developments and strategies for the future, in minerals research and exploitation.

Jan 1, 1986

The paper continues an account, begun in a previous paper, of experimental work carried out by the author whilst a member of the metallurgical staff at the Cockle Creek Works. The general method of the description of the plant and works practice adopted previously has been followed.The paper is a short account of the methods used in and the results of an investigation of the fume losses from the various parts of the plant.MEASUREMENT OF VOLUMETwo independent methods were used. The first depended on a number of pitot-tube measurements of velocity. These readings were taken in the stacks leading from the various furnaces at a considerable height above the ground so as to obtain as regular conditions as possible at the points where the readings were taken.Three openings were made in each stack and the pitot tube inserted into each opening in turn and readings taken at the centres of imaginary areas of equal size. The average velocity in the stack was thus obtained.After four tests had been made at the smelter stack, which removed the gases from all blast furnaces in use, the centre of velocity of the gases for each test was calculated and was found to be practically constant in position. The previous procedure was varied in subsequent tests on this stack by taking a succession of readings at the centre of velocity instead of at various points...

Jan 1, 1925

By C G. Sweeney

The underground mining industry is seeing unprecedented shortages in skilled labour. Migration to Australia being at an all-time low is a leading concern, with pandemic-induced border closures and lockdowns only exacerbating the skills shortage, not causing it. The skills shortage is forecast to peak in 2023 and remain high beyond 2025. With this skills shortage in mind, mining companies throughout Australia are trying to deal with stricter protocols around Health and Safety (H&S) legislation, as well as more stringent controls on quality assurance, particularly as underground mines are reaching greater depths and extending into ‘unchartered territory’. The cumulation of this is proving to be a major hurdle in ‘effective’ operational geotechnical management. The drive for automation in mining is bringing another level of complexity. However, ‘once automation is up and running, it presents the opportunity to access talent pools that may not normally be available. There is also a change in skillset that will be required to drive automation. ‘The top two emerging roles that will be critical for the future of the mining industry are artificial intelligence and machine learning (AI/ML) specialists, and process-automation specialists’ (Writer, 2021). If anything positive has come from the pandemic, it has shown that remote working can be effective and that the drive for automation and critical evaluation of skills required on-site should be given greater priority. UQ acknowledges that the industry is changing, and that digital technology is required to be offered in mining related disciplines. Industry and academia need to do more to promote geotechnical engineering in mining and balance the curriculum to suit the future of mining and make it more enticing. The average cost of a geotechnical failure is about $5 million in coalmines and can be into the hundreds of millions of dollars if production is affected (Cartledge Mining and Geotechnics, 2020). The cost of a good geotechnical design far outweighs the potential losses if a failure were to occur. This alludes to the growing importance of experienced geotechnical consultancies playing a pivotal role in managing mine site geotechnical hazards, while the industry is developing the next generation of geotechnical engineers.

Nov 29, 2022

By M Rea, E O’Connell

Decarbonising explosives manufacturing and catalysing low-carbon mining supply is a significant global challenge. Low-carbon manufacturing precincts – clusters of geographically close businesses across multiple industries that share a goal of adopting firmed renewable energy and decarbonising process emissions – offer one potential solution. In an Australian first, Orica commissioned tertiary catalyst abatement technology in 2023 to mitigate greenhouse gas (GHG) emissions at its Kooragang Island (KI) facility in New South Wales (NSW), Australia. The EnviNOx® technology (ThyssenKrupp Industrial Solutions AG, Dortmund, Germany) used reduces nitrous oxide (N2O), a potent greenhouse gas arising as a by-product of nitric acid manufacture. As a result, mining customers in NSW are now benefitting from ammonium nitrate (AN) products that are almost 50 per cent less emissions-intensive than those Orica previously offered. The $37 million project is a private-public partnership that has involved partners across Federal and State government, global engineering and technology vendors, local community groups and local carbon advisors to overcome financial barriers.

Sep 1, 2024

By D Brown, K Markovic, Z Tabor

From ancient times to the modern world, the mining industry has played a pivotal role in shaping the society that we live in today. It remains an integral part of everyday life and is a catalyst for both technological and economic growth. With finite resources on Earth, and growing pressures surrounding climate change and the environment, space mining opportunities have become of increasing interest. Recent discoveries have shown celestial bodies including the Moon and surrounding asteroids, contain an abundance of critical minerals, as well as resources necessary to sustain human life. These discoveries coupled with a transition into the digital and autonomous age, offer an innovative solution to solving some of the mining challenges currently being faced on Earth. Similarly, they also offer a pathway to enabling deep space exploration and off Earth exploratory missions. However, like with mining operations on Earth, space remains and immensely challenging and complex operational environment. The inhospitable nature of space poses new challenges, including communication barriers, lunar dust, cosmic radiation, and gravity. The challenges and risks are not just technological, as Environmental, Social, and Governance (ESG) factors must also be considered to prevent unintended consequences and hazards. Furthermore, future workforce, law, financial, and security systems must evolve to enable space mining to take place. These are all known aspects to begin with, but as the complexity of the space grows it becomes apparent that a holistic approach to assess and manage these factors will be required.

Sep 1, 2024

Low-grade, porphyry copper type mineralization at the Moonmera prospect is related to the intrusion of a granodiorite porphyry mass into the Upper Permian "Gracemere granodiorite". Significant copper mineraliza- tion appears to be associated with the alteration assemblage quartz-sericite- kaolinite. The ore shell is surrounded by a zone where montmorillonite and kaolinite are in greater abundance and this assemblage is over- lapped, mainly at depth, by potassium feldspar alteration. Secondary biotite is abundant throughout the mineralized zone. Preliminary sulphur isotope results on the sulphide mineralization are compatible with a magmatic origin for the sulphur.

Jan 1, 1974

By M Habte

This paper presents a simplified method for the assessment of creep deformations in rock masses containing bands of low strength or soil strength rock. The main impetus for this work was the need to assess the impact of distinct bands of clay and/or low strength rock on the long term deformation behaviour of a rock pillar formed as part of a series of proposed tunnelling works. In particular, the authors were interested in being able to provide criterion which could be used by site personnel to assess the encountered rock conditions against design assumptions.Creep deformation versus time plots are presented for a range of material consistencies. These plots were produced using the hyperbolic creep equation proposed by Mesri et al (1981). This empirically based equation was chosen for its simplicity and practicality. Discussion is included regarding typical input parameter values and the sensitivity of the results to these values is explored. Finally, in the soil strength materials, the secondary consolidation equation is used to check the veracity of the results calculated using the hyperbolic creep equation.

Mar 8, 2011

By C L. McIntosh

The west coast of New Zealand’s south island is host to a large number of placer goldfields that stretch from the Westport area in the north to Gillespies Beach in the south and inland to the foothills of the Southern Alps. This area is host to a large number of alluvial, glacial and strand line deposits ageing in range from Recent to Tertiary. In recent years exploration models have been developed for off shore placer deposits on the continental shelf.Gold mining on the west coast has exploited placer gold resources from the 1860s to present, and with the recent surge in the gold price the industry is currently undergoing a resurgence. The current increase in mining is dominated by small-scale mechanical operations usually involving one to two people at each site; a few larger operations also exist such as the Grey River Dredge.Mining methods range from using floating bucket dredges to small diggers. Some of the mining technologies used are similar to those employed during the great gold rushes of the 19th century. Exploration and grade control techniques can be very rudimentary often relying on previous sampling programs or wide spaced bulk sample drill holes. Some bulk sample drilling is used on the larger operations as a form of grade control, most of the small operations tend not to use any ore control sampling prior to mining. Extraction techniques relying on simple gravity based designs with riffle tables or spirals are the most commonly used. Environmental standards are very high within New Zealand and require operators to return mined areas to preagreed to landforms. The high rainfall experienced on the west coast causes challenges to operators in regard to water quality. Technical issues combined with often limited capital provide for challenges to the operations.

Aug 22, 2011

By J Poniewierski, Varcos D

Efficient blasting requires constant vigilance with respect to the actual layout being used in the field. Objective measurement techniques are required in laying out a pattern as the 'by eye' or 'thumb suck' methods cannot guarantee consistent results in layout. Erratic blast results are the consequence of such an approach. In a case study at Sons of Gwalia mine, it was demonstrated that incorrect front burdens had a snowballing effect on otherwise carefully laid out blasts, resulting in both excessive amounts of boulders caused by preconditioning of bench fronts and tops, and tight digging. Both problems caused lower excavator productivity and excessive excavator damage, as well as making it difficult to set out subsequent blasts correctly. Several field measurement methods are available to aid in determining correct blast layouts and one is described in this paper.

Jan 1, 1994

By P A. Montoya

La Colosa is a world-class porphyry Au project located in Colombia, currently undergoing prefeasibility analysis. As part of collaboration between AngloGold Ashanti and the AMIRA P843A GeMIII Project, the application of emerging geometallurgical characterisation testing and modelling tools has been incorporated in early stages of project development. The aim of the geometallurgical study is to map inherent comminution variability across the La Colosa deposit providing information critical for mine/mill design and optimisation. In this study, site-based data incorporating multi-element assays, quantitative analyse X-ray difraction QXRD bulk mineralogy measurements, EQUOtip rebound hardness data, and routine geological logging information from 59 diamond drill holes has been integrated with a range of geometallurgically specific comminution test (ie GeMCi, A × b, BMWi). The work in this paper demonstrates the integration techniques used at La Colosa to link routine data acquisition methods with comminution test results through the development of proxy support models. The integration incorporates a range of statistical techniques including principal component analysis and regression modelling. By creating proxy models, comminution index estimates can be propagated into the geological database enabling comminution processing domains to be defined. These domains provide the first spatial representation of comminution performance and variability at La Colosa and can be compared against traditional geological domains. This study provides the foundation for ongoing comminution characterisation as the La Colosa project evolves through project cycles into an operational mine.

Sep 5, 2011

By P J. Howard

Atlas Iron Limited’s McCamey’s North project lies at the eastern end of the Hamersley Basin, approximately 50 km east of Newman, Western Australia, and 3 km northeast of BHP Billiton’s Jimblebar Mine. The presence of significant surface iron mineralisation identified during field reconnaissance, has subsequently been further defined by detailed mapping and RC drilling.The project area is dominated by outcrops of moderate to steeply north and south dipping banded iron formation, cherts and shales of the Boolgeeda Iron Formation overlying rhyolites and rhyodacites of the Woongarra Volcanics. In lower lying areas recent colluvium and alluvium mask the Archaean geology. Drilling and downhole geophysics has allowed a composite stratigraphic section to be compiled through almost the entire Boolgeeda Iron Formation.Surface orientations and subsurface stratigraphic correlations using natural gamma logs indicate large scale open folding about east-west trending fold axes across the project area; while small scale tight to isoclinal folding with similar fold axis orientations are visible at the outcrop scale. These folds are cut by a number of moderate to steeply south-dipping normal faults defining a series of north-dipping fault blocks which repeat the stratigraphy across the project area.Bedded iron mineralisation consists mainly of haematite-martite and goethite ores with best results of 78 m @ 60.5 per cent Fe. Vitreous goethite is observed at the surface of the mineralised horizons. The mineralisation exhibits a strong stratigraphic control and extend down-dip up to 120 m below surface. The strike extent of the mineralisation is still to be determined. An inferred resource of 39 Mt at 58 per cent Fe has been defi ned to date (ASX: AGO 3 February 2011).The fi ndings at McCamey’s North indicate that there is potential for economic iron mineralisation to exist in other areas of Boolgeeda Iron Formation within the Hamersley Basin.

Jul 11, 2011

The Managalase area is remote and little visited by geologists or prospectors. Yet it holds the key to the tectonics and petrology of this part of Papua. The eastern Managalase plateau (M, Figure 1) lies between the Hydrographers andesite volcano (H) and Sesara shoshonite volcano (S) to the south of Popondetta on the Papua Peninsular. It contains over 30 small volcanic centres in an area of only 400 km2 . To the south and west lies the basic-utrabasic belt (B-UB) of the Morobe arc. This is the leading edge of oceanic plate obducted over the Owen Stanley Metamorphics during the lower Eocene time. To the east and southeast lies the Cape Vogel geosyncline where the western end of the Woodlark basin spreading centre enters mainland Papua. The extension of the spreading centre as a suture might pass as far as the southern margin of the Musa Coastal plain. A new pattern of plate tectonic motions has been determined by the global positioning system and the southern margin of the Woodlark plate has been redefined (Tregoning et al, 1998; Taylor, Goodliffe and Martinez, et al, 1999). The Managalase plateau is margined by two inferred faults. These outline a cusp protruding from the main basic-ultrabasic belt where these rocks are near the surface. The westerly arm of the cusp passes through the centres of the Hydrographers and Mount Lamington andesitic volcanoes. Mount Lamington overlies Quaternary alluvium and underlying Tertiary sediments (Arculus et al, 1983) but members of the basic-ultrabasic belt crop out on the southern flanks. The easterly arm of the cusp is an inferred shear zone (and ? fault) connecting up with the terminus of the suture on the Musa coastal plain. Movements on the two faults forming the cusp are thought to have produced the conjugate N-S, E-W faults on the plateau (Ruxton, 1966). To the east, and isolated, are the two large andesitic stratovolcanoes of Mounts Victory (V) and Trafalgar (T) which together form Cape Nelson. Mount Victory was last active in the 1890s. The Waiowa shoshonitic volcano explosion centres (W), last active in 1943 - 1944, lie near the suture adjacent to the actively rising Goropu mountains. Extension in these mountains is clearly demonstrated by the soil profiles being skeletal along a bounding fault and ageing uphill. The incision of small parallel ravines also dig deeper further upslope from the fault. To the south-east of Mount Suckling (K) the Dayman Dome is also an expanding mass. The Owen Stanley fault is parallel, and located to the south of the suture. The Mesozoic metamorphics form the backbone of the Papuan Peninsula. The intramontane Musa Trough is thought to date from the mid-Tertiary. At the eastern end of the trough Pleistocene and Recent ultrabasic breccias and alkali basalt crop out (Green, 1961).

Jan 1, 1999

By V A. Diemar

The Chatree Gold Project represents a greenfields discovery of metallurgically clean shallow gold mineralisation in a logistically simple terrain. Total Measured, Indicated and Inferred Resources are currently 31 tonnes of gold and 160 tonnes of silver. Gold occurs in an adularia-sericite epithermal system within quartz-calcite-adularia veins, breccias and stockworks. Host rocks are volcanic arc porphyritic latite-trachyte flows, their pyroclastic equivalents and volcaniclastics of upper Permian to upper Triassic age. The mineralisation was deposited in dilated zones during repeated reactivation of pre-existing structures. To-date five mineralised prospects have been defined by drilling with three reaching JORC Code Mineral Resources status. The project is in its definitive feasibility stage and is anticipated to be in construction during 2000.

Jan 1, 1999

A mathematical model for spontaneous combustion of coal with moisture included is presented in this paper. The one-dimensional unsteady state model consists of conservation equations for oxygen, water vapour and inherent moisture of coal and energy for both gaseous and solid phases. A first order Arrhenius reaction rate for oxidation under both pore diffusion and chemically controlled reaction regime is considered. The rate of evaporation or condensation is also considered as a function of temperature of coal, water content of coal and gas streams. The equation of the model is solved numerically by the finite difference technique. Influences of different parameters on the process of spontaneous combustion can be examined by using this model. Also the model can be used to simulate full-scale storage conditions.

Jan 1, 2005

By W M. Tekano, T S. Coulter, N M. Hutt

The Vancouver Island Highway Project (VIHP) was a $CAD 1.2 billion expenditure by the Province of British Columbia to improve travel safety and relieve traffic congestion between Victoria and Campbell River on Vancouver Island. In the section of highway between the Tsolum River and Oyster River, on the Inland Island Highway portion of the VIHP, over half of the rock to be cut and filled was found to be net acid generating. The Tsolum River has been impacted by metal leaching and acid rock drainage (ML/ARD) for decades from an upstream closed minesite. Geochemical testwork indicated: over half of the rock along this section of highway was potentially net acid generating based on a site-specific SNPR (=NP/SAP) criterion of 1.5; some core samples were already acidic; pyrite occurred in disseminated framboidal and gel forms; the rate of acid generation was not high; measured neutralisation potential (NP) provided some lag time for the onset of net acidity; and non-carbonate neutralising minerals prevented low pH (These predictions led to ML/ARD controls involving: realignment of the highway; elevation control to minimise the volume of disturbed rock; encapsulation of blasted-rock fills within the highway, surrounded by low-permeability till and covered with asphalt; and diversion of water away from cut faces. Internal pipes drained any water reaching the fills into external ditches and ponds, where the water could be monitored and, if necessary, treated. Water from the cuts was also captured in ditches and carried to monitored ponds. Elevated aqueous sulfate concentrations in several ponds confirmed that sulfide minerals were oxidising, but the lack of both acidic pH and increasing trends in concentrations demonstrated that ML/ARD was controlled. Contingency plans for any pond that may become acidic include water treatment, which predictive testwork has shown would not require substantial amounts of limestone or lime.

Jan 1, 2003