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This paper outlines the role of commissioning in the project cycle, shows how to get organised for commissioning and describes the principal commissioning activities. Emphasis is placed on appointing key commissioning staff early in the project to coordinate the preparations for commissioning and on detailed planning and tracking to ensure that the required commissioning activities are performed satisfactorily. The management of safety during commissioning is reviewed.

Jan 1, 2005

By M Manefield, G Bournival, S Ata

Asteroids contain an abundance of valuable resources such as: nickel, cobalt, gold, platinum and rhodium. Whilst the consumption of mineral resources on Earth continues to deplete, meteoroids have the potential to become a significant source of minerals. Even though the minerals content of asteroids may be relatively high, the valuable minerals are more likely to be only a small portion of the total ore present in the main body. The ores must, therefore, be processed to extract the metals of interest from the waste. Existing terrestrial technologies rely on manipulating the physical and chemical properties of minerals. The application of these techniques to asteroids processing, however, is not straightforward due to the presence of different conditions such as zero gravity and lack of water in space. This paper discusses potential separation and extraction techniques that can be used for processing of asteroids.CITATION:Ata, S, Bournival, G and Manefield, M, 2015. Resource recovery in space, in Proceedings Third International Future Mining Conference, pp 275–280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

Determining the controls of high-grade mineralisation at Vera Nancy requires careful data collection and assessment on a global and specific deposit basis. The techniques developed over 60 years ago to analyse structure, grade and width data are just as applicable today and can be enhanced using modern geological modelling software. High ore grades at Vera Nancy are controlled by both the primary geometry of the mineralised structure and the intersections of the main mineralised veins with subordinate splay veins. The main mineralised structure dilated as a consequence of extensional tectonics while the splays acted as conduits bringing oxidising surficial fluids into mixing zones precipitating high gold grades. Near-mine exploration is focussed on identifying zones of vein flexure and splay interaction to locate the relatively small high-grade shoots. Data modelling in a 3D environment is an essential process for understanding the geometry of the system being explored.

Jan 1, 2000

By C Rizos, A Ng

Land surface deformation can be caused by underground mining activities. The maximum subsidence normally occurs directly above the location of the excavation of the coal seam. In the case where the longwall mining technique is applied, the magnitude and shape of the subsidence bowl are constrained by the longwall structure (pillar). This paper describes the use of satellite radar interferometry for monitoring surface subsidence due to underground mining, as a cost-effective geodetic technique and complementary to conventional ground surveying techniques. This paper uses data acquired by the current generation of SAR satellites û the European ENVISAT and the Japanese ALOS û to monitor ground subsidence in the southern highland coalfield in New South Wales, Australia. An accumulated DInSAR subsidence mine map is produced using six successive ALOS acquisitions. The results are post-analysed with the aid of geographic information systems (GIS) and validated using ground survey data.

Jan 1, 2008

By S H. Li, H Z. Gu, A Huang

High aluminium steel is a promising advanced steel known for its exception properties and holds significant economic and strategic importance. However, the CaO-Al2O3-SiO2 based slag with high alumina content reacts vigorously with alumina refractories during the smelting process at high temperature, seriously affecting the safe and efficient production of furnaces and resulting in the formation of Al2O3-MgO non-metallic inclusions within the molten steel. This is a bottleneck problem for high-quality steel refining, and the key reaction path during the corrosion remains unclear. The dissolution reaction mechanism of alumina refractories in high alumina CaO-Al2O3-SiO2 slags under a weak static magnetic field was investigated in this work, using high temperature laser confocal microscopy and in situ radiation spectroscopy techniques. The results indicate that the interaction between the high alumina slags and the alumina refractories is governed by free radical reactions. The dissolution of alumina forms AlO and AlO2 radicals. The reaction rate increases with the C/S ratio of the slag due to its low polymerisation. The reaction between non-bridging oxygen and AlO2 free radicals accelerates the generation of AlO and O2ꞏ- radicals. The reaction layer composed of calcium aluminate is formed through the recombination of AlO, Caꞏ+ and O2ꞏ- radicals. The weak static magnetic field induces the Zeeman splitting of free radical pairs and intersystem crossing occurs, promoting the formation of triplet free radical pairs through the hyper-fine coupling effect. The reaction can be significantly inhibited as the triplet free radical pair does not meet Pauli’s incompatibility principle. This discovery perfects the structure theory of molten slags with radicals and provides supplement to the design of the highly slag-resistant refractories, and provides the theoretical basis for the development of external field protection technologies for high-quality steel refining.

Jun 19, 2024

By K C. Corin, C T. O’Connor

In recent years it has been shown that the concept of using partial molar excess Gibbs energy (G̅ex) to explain the behaviour of collectors in the recovery of minerals can be usefully applied to explain flotation performance. Fundamentally this is because hydrophobicity of a mineral particle on which a collector is adsorbed may be strongly related to the fact that the alkyl chain associated with the collector behaves in the same way as any hydrocarbon would in an aqueous medium. This hydrocarbon-water system represents a classical non-ideal mixture, and such mixtures are quantified thermodynamically by determining the activity coefficient of the hydrocarbon moiety of the collector and hence its G̅ex in the mixture. It has been shown that G̅ex is a more rigorous indicator of the contributions of various alkyl groups of a collector than HLB (Corin and O’Connor, 2014) and was also able to explain aspects of froth behaviour (Harris and O’Connor, 2017) and hydrophobicity (O’Connor, 2021). The present paper is aimed at extending the above concepts in two different ways. Firstly, a study is undertaken of a range of results previously reported in which various reagents containing different alkyl groups were analysed in terms of their effect on contact angle and their performance as flotation reagents in terms of recovery. These results sustain the previous observations that there is a robust positive relationship between hydrophobicity as indicated by flotation recovery and contact angle and G̅ex of the alkyl group associated with the collector. Secondly, on the basis of the observation that increases in G̅ex are indicative of increases in the hydrophobicity of the mineral particle-collector aggregate, a study was undertaken to examine the effect of ions typical of electrolytes in water as well as the effect of the presence of alcohols and of pH on G̅ex of the collector alkyl group. In the former two instances the absence of any correlation between G̅ex and recoveries supported the proposition of the respective authors of these studies that the major effect of these electrolytes and added alcohols may be on particle–bubble attachment rather than on the hydrophobicity of the mineral/collector in the aqueous system. On the other hand, the effect of pH on G̅ex correlated reasonably well with changes reported in the literature on the effect of pH on recovery and contact angle.

Aug 24, 2022

By P J. Hawke

Within the Mesa J pisolitic iron ore mine, clay is distributed unevenly throughout the deposit and often forms as pods and channels less than 10 m in width. The mine resource model, based on 50 m + 50 m spaced drilling, has been unable to accurately delineate the clay for scheduling and mining purposes. Therefore, alternative methods for mapping the clay-contaminated ore were sought. Predictive clay mapping will significantly reduce production costs at Mesa J through improved selective mining practices, more accurate scheduling, reduced wear on mining equipment and minimising the need for maintenance of haul roads and ramps. High lateral resolution electromagnetic (EM) surveying using a Geonics EM31 instrument can quickly and inexpensively delineate the extent and orientation of the clays. Preliminary results indicate that a block model based on the interpretation of the EM data can accurately predict the distribution, volume and tonnage of ore and waste material. While rip-line mapping, infill drilling, ground penetrating radar and gravity can delineate clay with various degrees of success, none were as efficient as EM31.

Jan 1, 2002

By T Gready

Stawell Gold Mines operates the Magdala underground mine in western Victoria, Australia. Several orebodies are extracted by longhole open stoping at a depth of 900 m below the town of Stawell. Some stopes are backfilled with cemented slurry rock fill (CSRF) to ensure stability, increase recovery of ore reserves, minimise dilution of ore grades, and add value to the project. StawellÆs simple CSRF system is described, including the novel equipment used to minimise capital costs. Design criteria, operating procedures, monitoring systems and results are discussed in detail. Practical aspects are considered, including lessons learnt about barricades, overbreak and segregation. The economics of CSRF are discussed, including capital costs, operating costs and the total cost per ounce of gold poured. Options for mining with and without CSRF are compared in terms of return on investment and net cash flows. Examples demonstrate the method used to calculate æbreak-evenÆ stope ore grades which determine whether or not CSRF will add value in different circumstances.

Jan 1, 2002

By S Hapugoda, A Edenton, M Adam, R J. Holmes, J R. Manuel, R Smyth

Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, normally accounting for ten to 20 per cent of the blast furnace burden. Like other feeds, the characteristics of lump ore have an important impact on the stable operation and productivity of the blast furnace. Lump ore is usually assessed chemically, physically and mineralogically to establish its likely blast furnace performance. The physical characteristics of lump ore are strongly related to the chemistry, mineralogy and texture of the ore involved. In this paper, the blast furnace ironmaking process is reviewed, with particular emphasis on the key quality requirements for the ferrous burden material. A variety of key physical characteristics of lump ore measured using standard and non-standard methods are then described and subsequently correlated with the chemical and mineralogical characteristics of the ore wherever possible. Finally, the impact of these physical characteristics on blast furnace operation is assessed.

Jan 1, 2009

By I Manege, S M. Bennett

The PT Kaltim Prima Coal (KPC) operation is a large scale coalmine operating on the east coast of Kalimantan (Borneo), Indonesia. Originally developed under a coal contract of work (CCOW) with the Indonesian Government, new legislation has led to uncertainty as to the actual life of the mine, the size of the operating lease or mining area, the rehabilitation compliance requirements and other areas of concern. The actual life-of-mine (LOM) plan is therefore in a constant state of flux and must be updated and modified with every new piece of information.Under the CCOW system, the mine life ran from the first year of production (1992) for 30 years (2021), with the potential to extend for a further two ten-year periods. KPC has always intended to run until at least 2041. Under the new legislation, the potential term of the CCOW (to be replaced by a mining license) is open to interpretation, resulting in KPC having to prepare plans allowing for a LOM that may end in 2021, 2031, 2041 or a range of other possible periods of time.Uncertainty about legislation (and hence the mine life) possible production rates and available work areas; variable coal prices and costs; varying management contexts; the substantial reserves available; difficulty sourcing dump space; potential rehabilitation costs and the dependence of a community of over 100 000 people on a single operation sees the LOM and mine closure teams preparing dynamic yet thoroughly robust plans that are updated on multiple occasions per year.This paper will describe the procedure followed by KPC and the potentially show stopping issues that must be dealt with.CITATION:Bennett, S M and Manege, I, ?2014. Life-of-mine planning in a dynamic environment, in Proceedings Life-of-Mine 2014 , pp 379–388 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By M R. Davidson, M P. Schwarz

A model for column bioleaching is investigated to identify and understand aspects of bacteria in bioleaching applications, which have implications in heap bioleaching operations. The model is used to simulate scenarios that would otherwise be time consuming to perform experimentally. This study uses a model of bacterial transport and attachment/detachment to ore particles, with a bioleaching model for the depletion of a copper-sulfide, also accounting for liquid and gas flow and gas/liquid oxygen mass transfer. The model includes aspects such as oxygen and ferrous ion consumption, coupled with leaching of a copper-sulfide via the shrinking core model. The model is used to investigate how the rate of leaching is affected by the bacterial concentration in the columns, by the bacterial regeneration of the leaching oxidant ferric ions. The model is also used to assess the impact of oxygen limitation and inoculation method on the copper leaching. Some comparison of the model with experimental data will be shown.

Jan 1, 2004

Mechanical and electrical (M&E) systems in road tunnels are constrained by the traffic envelope and the construction profile. Whilst these spatial constraints are often ælocked inÆ early in the design process, the detailed M&E design continues for some considerable time after key civil engineering issues have been resolved. Ventilation design criteria for both normal and emergency operation often involves considerable negotiation with a wide range of stakeholders. Final system performance and spatial requirements are only finally resolved when suppliers are selected following the tender process. Lighting design is dependent upon a wide range of factors including tunnel lining materials and associated colours as well as agreed maintenance regimes. Cabling systems can only be developed when the general arrangement for power distribution is agreed and a system of substation, switchrooms and equipment rooms is in place. Many other systems such as fire protection and communications facilities fill the available space beyond the traffic envelope, where physical, structural and æsight lineÆ requirements must all be accommodated. The more co-ordinated civil engineering and M&E design is and the earlier the process starts the better the outcomes for all parties.

Jan 1, 1999

By E Yurakov, D J. Ashelford, M I. Slate

The push for increasing coal production rates continues to place increasing demands on mine management to safely and effectively control seam gas. Gas drainage strategies applied vary in both effectiveness and form. Methods employed are a function of assessed risk, gas reservoir characteristics, surface and underground access, budgetary constraints and gas utilisation potential. With the aim of establishing and optimising the effectiveness and efficiency of gas drainage systems, Australian coal miners in cooperation with gas management specialists are embracing the use of gas reservoir simulators and gas emission models. This paper discusses the evolution of gas drainage practices in Australian underground coal mines and the role of gas reservoir assessment methods in optimising gas drainage systems and gas production forecasts.

Jan 1, 2005

Mining is still a significant economic activity within the Hauraki District. The Martha project is particularly significant. Estimates are that in the order of 850 direct and indirect jobs are derived as a consequence of the Martha project within the Waikato Region. The Resource Management Act 1991 (RMA) is New Zealand's primary piece of environmental legislation. It sets out to provide the framework for the control of the use, development and protection of almost all physical and natural resources. Minerals are excluded from the sustainability requirements of the legislation but as mining invariably involves the use of land, all the other elements of RMA apply. The Council's role in dealing with mining changed with the introduction of RMA. It became responsible for administration of those matters that fell within the functions set out in section 31 of the RMA in respect to existing authorisations. Mineral development needed to be considered in the development of the District Plan that the Council is required to prepare. Implementation of the Act has been a challenge for not only local government but for many industries and resource users since it came into force in 1991. There have been, and are, differing views on both the way it is administered and its intent. The Hauraki District Council has been at the forefront of some of the challenges that are a consequence of the Act. Its reactions to these challenges have been consistent. It treats mining in the same why it treats any other industry. At times this approach has not been understood and without challenge from sections of the community.

Jan 1, 2000

By G M. Volkmann

Pipe umbrella systems have effectively been used as an additional support system in the working area in weak ground conditions during the last decades. Thus, a considerable number of applications accounts in urban tunnelling with shallow overburden. However, this support system is also successfully used when a tunnel alignment crosses fault zones, sediments, moraines or talus with overburdens from shallow to deep. The pipe umbrella support system itself is termed differently worldwide – synonyms are canopy tube umbrella method, umbrella arch method, or long fore-poling method.One main reason for the increase in application is that this support system closes cost-effectively the gap between reasonable, normal supported tunnels and tunnels supported with more expensive special techniques like horizontal jet-grouting or ground freezing. By using this system, many projects can be built more cost effective without decreasing the common level of safety.The pipe umbrella construction method is pretty young, so the knowledge about this system has been intensely researched in the last decade. This led to an enormous increase in understanding the interaction between support system and surrounding ground, the mode of action, and the important details for construction.Pipe umbrella support systems are applied in difficult ground conditions, so a special developed measurement arrangement was used to observe deformations ahead of the working face during tunnelling. The evaluation of collected data sets identifi ed that cased-drilling systems have clear advantages compared to predrilling systems during the installation process in weak ground conditions. This may become important depending on project requirements, so this difference must be considered in design as well as in the tender document specifications.

Mar 8, 2011

By C D. Strickland

Western Australia (WA) has been a significant world producer of titanium minerals (rutile, ilmenite and leucoxene) and zircon for over 55 years. In 2010, despite global difficulties, WA accounted for 12 per cent of world production for zircon, ten per cent for ilmenite, and eight per cent for rutile. With downstream processing, titanium minerals (ilmenite, rutile, leucoxene) and zircon exports for 2010 were valued at $511 M (Department of Mines and Petroleum, 2010).Production is dominated by two areas of the Perth Basin, namely the Eneabba and the Bunbury-Capel regions, which are located 240 km north and 200 km south of Perth respectively. Mineralisation is within Cenozoic beach or near shore dune deposits at three broad altitudes related to the present coastline, and two older higher sea-level still-stands. The titanium-zircon minerals presumably were derived from the underlying Mesozoic sediments of the Perth Basin. Contrary to expectations, age dating suggests that the ultimate source of most of this mineralisation was not the adjacent Yilgarn Craton. With the cooperation of industry, the Geological Survey of Western Australia has mapped all known significant titanium-zircon mineralisation within the Perth Basin. This mapping has identified ‘strategic mineral resource protection areas’ that should be set aside for future mining, ‘sterilised’ and ‘mined’ areas that generally do not restrict land use options, and ‘possible strategic resource areas’ which have exploration potential for hosting titanium-zircon mineral deposits.The Perth Basin is currently undergoing rapid residential and industrial development. By informing all stakeholders of the locations of potential mining areas, the titanium-zircon mapping has the ability to reduce future land use conflicts, and facilitate sequential land use planning. Appropriate planning measures are being implemented to ensure that the Western Australia’s titanium-zircon minerals industry remains strong and viable in the future.

Oct 5, 2011

By Saghafi A, Kelly M, Williams R. J

A two year program of research into the feasibility of long-hole drilling for improved gas emission control has been undertaken at Appin Colliery. State of the art equipment was employed involving cableless electronic surveying and down-hole motor drilling. The project involved the drilling of 1000 m long, in-seam boreholes in the Bulli seam and boreholes of similar length drilled cross measure and then in-seam along the underlying Balgownie seam. A new concept for gas drainage was defined, employing long-holes for both predrainage and post drainage.

Jan 1, 1988

By S Bluhm, R Funnell

Creative mine-designs are constantly being applied in the deep platinum mining industry in South Africa. Recently, this has resulted in deep hot mine-designs including room and pillar, bord and pillar or stall and pillar layouts and the use of in-stope trackless mechanisation. In these mines, the ventilation systems use refrigerated air and high fan pressures and as a result ventilation leakage can have a huge impact. Leakage is a serious impediment to cost-effective operation and potential leakage in future projects is a major factor in judging project viability. This paper describes certain mine layouts and quantifies the extent of the leakage. Based on typical field data, a range of seals from ævery poorÆ to ævery goodÆ was defined and used to estimate overall leakage. Within these mine networks the ventilation pressure, temperature and density all vary significantly and with the multiplicity of leakage paths it was necessary to make use of the VUMA-network simulation package. For the examples examined, the leakage was found to be up to 85 per cent for æpoorÆ category seals and up to 50 per cent for ægoodÆ category seals. The total air flow (and refrigeration) requirements grow exponentially with strike distance due to the compounding effects of higher pressure and more leakage paths. It is shown that beyond certain depths and strike distances the leakage will become so great that it will be impossible to operate cost-effectively û even with ægoodÆ seals. Indeed, in these examples the projects were not considered viable in their original format because of the high ventilation-cooling costs and the mine-designs were modified to include footwall drive systems û the cost of which was justified by the reduced strategic risk to operating ineffectiveness due to leakage.

Jan 1, 2005

By H G. Poulos

Prediction of ground deformation caused by soft ground tunnelling is an important problem facing design engineers. The ground deformations are caused by the closure of the gap formed around the tunnel due to the tunnelling procedure and soil intrusion via the tunnel face into the tunnel. There are three different approaches that are commonly used in practice to estimate the ground deformations due to tunnelling, namely, empirical methods, analytical methods and finite element methods. One of the important issues of tunnelling in urban areas is the assessment of the likely impact on adjacent pile foundations of ground movements arising from tunnel construction. The main objectives of this paper are two-fold: first, to assess the available methods to estimate the tunnelling-induced ground deformations, and second, to examine the effect of such ground deformations on adjacent piles. Analytical solutions to predict the tunnelling-induced ground deformation developed by the authors are used in this study. These estimated ground deformations are imposed on the pile in simplified boundary element analyses to compute pile responses. The influence of various factors such as tunnel geometry, ground loss ratio, pile diameter and ratio of pile length to tunnel depth are examined in this study.

Jan 1, 1999

By F Minz, P Lamberg, A Mwanga, C Lund, C Wanhainen, M Amiri Parian, J Rosenkranz

A geometallurgical model is currently built in two different ways. The first and the most common way relies on geometallurgical testing, where a large number of samples are analysed for metallurgical response using small-scale laboratory tests, eg Davis tube testing. The second, mineralogical approach focuses on collecting mineralogical information over the orebody and building the metallurgical model based on mineralogy. At Lules University of Technology, Sweden, the latter method has been adopted and taken further in four ongoing PhD studies. The geological model gives modal composition by the help of element-to-mineral conversion and Rietveld X-ray diffraction. Texturally, the orebody is divided into different archetypes, and liberation measurements for each of them are carried out in processing fineness using IncaMineral, a SEM-based technique. The grindability and liberation spectrum of any given geological unit (sample, ore block, domain) are extrapolated from the archetypes. The process model is taken into a liberation level by mass balancing selected metallurgical tests using the particle tracking technique. The approach is general and can be applied to any type of ores. Examples of ongoing studies on iron and massive sulfide ores are given.CITATION:Lamberg, P, Rosenkranz, J, Wanhainen, C, Lund, C, Minz, F, Mwanga, A and Amiri Parian, M, 2013. Building a geometallurgical model in iron ores using a mineralogical approach with liberation data, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 317-324 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013