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By Y Chen, G Xu, B Albijanic

High concentrations of airborne coal particles is the main reason leading to health and safety hazards in underground coalmines. Water spray is one of the effective methods to suppress coal particles in mine sites, but the use of plain water is not effective enough to capture coal particles. By adding surfactants, coal wettability can be improved which will increase the coal dust suppression efficiency. In this study, a modified sink test was employed to evaluate coal wettability in the presence of two anionic surfactants: sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS). Sink rates were calculated by measuring sink weight over test time. Different surfactant concentrations (0.01 per cent, 0.05 per cent, 0.1 per cent, 0.2 per cent and 0.4 per cent) and two types of water (tap water and deionised water) were selected to investigate coal wettability over three size ranges (0–38, 53–75 and 75–90 µm). The results show that both SDS and SDBS surfactants can lower the water surface tension and improve coal wetting performance. Sink rates increased as the surfactant concentration increased, and surfactant solutions prepared by tap water performed better than deionised water in enhancing coal wettability. Also, coal wettability varied for different coal particle sizes; the smaller coal particles were, the worse the wettability they possessed.CITATION:Chen, Y, Xu, G, Wang, R and Albijanic, B, 2017. Study on coal wettability for dust suppression in the presence of surfactants by sink test, in Proceedings Australian Mine Vent Conference 2017, pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Lawrie D. C

Finely ground beryl was decomposed by mixing with ground limestone and soda ash and heating at 900°C for 4-6 hr. The sintered mater:al was then crushed and leached by boiling under reflux with 5N sulphuric acid for up to 4 hr. The liquor containing Be, AI, Fe and other elements as sulphates, was separated from the residue which consisted mainly of silica and gypsum, either by filtration or bydecantation washing.The clarified leach liquor was first treated to remove Fe+++ by contacting with a primary amine-kerosene solution in 2 countercurrent stages. The iron free liquor was then passed to a 4-stage counter-current extraction unit where it was contacted with O·5M di- (2 ethyl hexyl) phosphoric acid (EHPA) in kerosene. Under the operating conditions, 99 per cent of the Be and 7 per cent of the Al was extracted.The Be and Al were stripped from the organic phase by sodium hydroxide solution of suitable concentration to form soluble "beryllate" and "aluminate" respectively. Most of the Be was subsequently precipitatedas Be(OH)2 by heating the alkaline solution to 90°C, the Al remaining in solution. After filtration and washing, the Be(OH)2 could be ignited directly to BeO at about 1000°C or used as a feed to further purification stages if required.A small counter-current extraction unit was operated continuously using liquor derived from the sintering and leaching stages. Dataobtained in batch laboratory tests were confirmed. A product obtained by ignition of the washed "beryllate" precipitate contained more than 99 per cent BeO.INTRODUCTIONIn 1958 an investigation was commenced into the recovery of beryllium oxide from beryl, as part of a programme to utilize mineral resources of South Australia. A survey of the literature indicated that little work had been done on direct solvent extraction of beryllium from aqueous liquors, so it was decided to apply the experience gained in this field in uranium processing to the current problem.Preliminary extraction tests on solutions of beryllium...

Jan 1, 1965

Grinding Mill Operation and Maintenance - Central to Asset Management Since 2005, RME has pursued a vision for a new grinding plant operational paradigm, made possible by RME's latest Mill Relining Systems. At some sites, new liners degrade SAG mill performance. The variables include mill volume loss, rotational speed limitations (ball strike) and liner designs developed for longer and longer life but without a backward glance at metallurgical consequences of whole plant performance. Freshly relined mills can initially deliver as little as 80 per cent of their maximum throughput, that maximum occurring toward the end of the liners' wear life. RME's proposition is to see new liners designed for maximum commercial performance. This may mean more frequent mill relines but with liners designed to yield optimum grinding, metallurgical and profitability performance, not maximum life. In other words, mill liner profiles and relining speed become key profitability contributors and not simply 'must do' maintenance functions and costs. This paper includes a short history of RME's Mill Relining System development (Appendix A). These are the enabling technologies which permit more frequent liner exchange without incurring additional downtime imposts. The body of this paper outlines RME's vision of a 'liner profile vs. profitability' commercial model, underpinned by the rigour of PAS 55-1:2008 Asset Management Part 1: Specification for the optimised management of physical assets. The technical elements can be developed either intuitively (based on plant experience) or by using a combination of new measurement and modelling technologies. These new measurement and modelling tools provide the opportunity to predict the optimum technical solution for the maximum commercial outcome. Much of this can be modelled off-line, in the virtual world, before asking senior management to commit to an expensive liner experiment. The potential benefits are compelling.

Sep 13, 2010

Mineral Processing Engineering Education in China - Bringing up the Engineering Diathesis and Design Competence of the College Students

Sep 13, 2010

The metallogenic map of New Zealand shows the distribution of metallic mineral deposits, according to type and size, in relation to their geological setting. The major purpose of the map and accompanying 200-page monograph is to summarise the distribution, modes of occurrence and origins of the metallic mineral deposits of New Zealand. The map demonstrates the prospectivity of New Zealand for metallic minerals, particularly gold, silver, iron, and titanium. Information on each deposit is summarised in index tables based on major geotectonic units or deposit/commodity type. The mineral deposits are arranged and discussed in relation to tectonostratigraphic and tectonomagmatic units or terranes, under broad geotectonic divisions of the Paleozoic to Mesozoic Western Province, the late Paleozoic to Mesozoic Eastern Province, the mid Cretaceous to early Tertiary rifting phase, and the late Cenozoic Kaikoura Orogen. Regions or areas of marked concentration of mineralisation are recognised as metallogenic subprovinces or districts, namely: eastern Northland (Hg), the Hauraki Goldfield (epithermal Au-Ag-Pb-Zn-Cu), the west coast of the North Island (shoreline placer Fe), east Nelson (podiform Cr), west Nelson (porphyry Mo), the West Coast of the South Island (shoreline placer Ti), west Nelson-Westland (placer Au), Reefton (mesothermal Au-quartz veins), and Otago (placer Au and mesothermal Au-W quartz veins).

Jan 1, 1993

By W E. Vance, B H. Ashton

The emission of seam gases into underground workings in coal mines is acknowledged as a major hazard, particularly methane due to its possible ignition. Acknowledge of seam gas parameters is important for the prediction of gas emission rates into the ventilating air current. They are also important as the basis for the evaluation of the likely contained gas as a possible energy source.   Gas content determinations for the Kupakupa seam have been made at the Huntly West Mine.  Applying the method of Creedy (1986) to face samples, gas contents of 1.80 and 1.66 have been determined. Using desorbed and residual gas content data a content of 1.92 m3/t has been derived. These are on an ash included basis. Calculations using the adsorption equation of Kim (1977) and coal quality have given a gas content of 2.19 m3 t. Long-hole exploration drilling at Huntly West Mine has provided information on gas pressure. A pressure rise test has given a reading of 500 kPa (absolute); this is low compared with the pressure given for the determined gas content from theoretical adsorption isotherms.

Jan 1, 1991

By Segnit E. R

Results are reported of a study of the reactions occurringin the combustion of chaIcopyrite particles underconditions simulating those in the shaft of a flashsmelter.The reactions were studied using kinetic and mineralogicaltechniques. Reactions. rates above 500°C wererapid, most of the reaction taking place in less than 50ms. Final products were copper-iron ferrites with spineltype structures. Probable reaction mechanisms are discussed.

Jan 1, 1977

Authors have been conducting research on autonomous loading operation by wheel loader. Autonomous loading cycles has been demonstrated with real size experimental model. In V shape loading operation, travelling between scooping point and dumping point is dominant factor for cycle time of the operation. The positions of scooping point and dumping point changes with advancing the operation. In the developed system, path planning is performed at the beginning of every cycle. The path is formed by combination of curve and straight path elements. During travelling on the planned path, path following control is applied on the loader to keep position error in narrow range. Positioning of the loader is based on dead reckoning with correction by global positioning system (GPS) data. In a process of path following control, control value for steering angle is determined based on position error in lateral direction. Proposed method of path planning and position control is installed and tested in the real size experimental model. The detail and results will be described in the paper.

Dec 6, 2010

By C A. Heinrich, J L. Walshe, V J. Wall

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

Separation of Nickel and Cobalt from Manganese, Magnesium and Calcium by Synergistic Solvent Extraction - From Batch Tests to Pilot Plant Operation The synergistic solvent extraction system consisting of Versatic 10/LIX63/TBP was used for the separation and purification of nickel and cobalt from synthetic laterite leach solution after iron removal. Very encouraging results were obtained for separating nickel and cobalt from manganese, magnesium and calcium. In batch tests, the organic composition of the synergistic system was optimised and very large synergistic shifts for nickel and cobalt were observed. The ?pH50(Mn-Co) and ?pH50(Mn-Ni) values were as large as 1.65 and 2.40, respectively. The extraction and stripping kinetics of nickel and cobalt was fast. Semi continuous extraction tests were conducted with a pH profile of 5.5/6.1/6.5 in three stages at 40¦C. The nickel and cobalt extractions reached 99.9 per cent with only 5 mg/L Ni and <1 mg/L Co left in the raffinate. With two stages of scrubbing, only 2 mg/L Mn and less than 1 mg/L Mg and Ca were left in the scrubbed organic solution. With two stripping stages, the stripping efficiencies of Ni and Co reached over 95 per cent. A fully continuous pilot plant operation was conducted successfully for 280 hours. With an O/A ratio of about 2 and a pH profile of 5.5/5.8/6.0/6.3 for the four stages EX1/EX2/Ex3/EX4, both nickel and cobalt were almost completely extracted. Using a pH profile of 5.4/5.0 for SC1/SC2, the manganese scrubbing efficiency was over 96 per cent. Using three strip stages, over 98 per cent Ni and 99 per cent Co were stripped with only 64 mg/L Ni in the stripped organic solution. The nickel concentration in the loaded strip liquor reached 83 g/L, resulting in a ?Ni of over 28 g/L. The chemical stability of the system was also assessed over 12 weeks under proposed industrial operating conditions. Operation exclusively under strip conditions at 50¦C and 40¦C resulted in LIX63 oxime half lives of 1.1 and 2.1 years, respectively. Operation exclusively under extract conditions at 50¦C and 40¦C resulted in oxime half lives of 0.26 and 0.82 years, respectively. Losses of Versatic 10 were less than four per cent.

Sep 13, 2010

By G Eastwood, C Joyce, P Ryan, G M. Johnston

Over the years, predictive techniques for Acid Mine Drainage (AMD) and the natural processes affecting acid generation have received considerable attention. Less emphasis has been placed on the sampling strategy and the integration of testwork results with the geological data base. The sampling strategy employed and the development of a geological model to determine the spatial distribution and volume of acid producing material are often crucial for developing cost-effective containment and mitigation measures. The geological model provides a link between the occurrence, timing, destination and placement of mined waste rock. Careful and accurate interrogation of a comprehensive geological database provides this linkage. The AMD testwork program at Cadia in NSW has been designed to identify the temporal selective handling requirements that will be required during operation. Sampling involved collection of representative combinations of all waste rock types identified within an extensive geological database. These samples were subjected to static, kinetic and accelerated weathering predictive tests. Preliminary results have been used to construct a waste block model for the deposit that identifies the quantity and distribution of acid producing material. Integration of the block model with the mine scheduling determines when the material will be mined.

Jan 1, 1996

By D O’Dea, B Godel, T Honeyands, B Ellis, T Harvey

X-ray computed tomography (XCT) is a non-destructive technique that allows the exploration of the internal structure of solid objects in 3D. Over the past ten years, the combination of XCT with more conventional 2D techniques and quantitative 3D image processing and analysis (commonly referred to as digital rocks) has allowed us to address some of the most challenging problems in ore deposit studies. The range of X-ray energies used in XCT allows the X-rays to be transmitted through complex and dense materials including iron ores (eg sinters, lumps, granules). Recent high-resolution XCT scanners have the ability to generate multiscale (25 down to 0.3 µm voxel size) imaging of a given sample enabling the characterisation of 3D textures across a range of scales. This paper will focus on the application of digital rocks to iron ore sinter particles (using filtered polychromatic X-ray beam). The paper is divided into three parts and includes: i) details on the methodologies including their benefits and limitations and the effect of spatial resolution; (ii) the quantification of pore network topology and pore characteristics (eg open versus closed pores, pore size distribution and pore morphologies; degree of connectivity of the pore network and its tortuosity); and (iii) the evaluation of the technique to characterise various phases within the material and quantify 3D mineral textures.CITATION:Godel, B, Ellis, B, O’Dea, D, Honeyands, T and Harvey, T, 2017. Digital rocks for iron ore sinters – towards a D quantification of sinter textures, in Proceedings Iron Ore 2017, pp 529–534 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

In order to appreciate fully the place of palaeontology within the general framework of the geological sciences, consideration must be given to the time, about 150 years ago, just before the study of fossils was beginning to be applied to geological problems. At theend of the eighteenth century, almost all geologists recognised that fossils were the remains of animals and plants that had lived at the time when the rocks in which they occur were formed. It was also realized that many-some geologists thought all-rocks hadbeen formed under water, but as regards the order of succession in which these rocks had originated, and the relative ages of rocks found in different parts of the world or even of one country, only the haziest and most contradictory ideas existed.Around the turn from the eighteenth to the nineteenth century, a widely taught system of theories was that of the German professor, Abraham Gottlob Werner, who believed that the surface of the earth had once been covered by a universal ocean at whose bottom all rocks had been deposited. As the level of this ocean gradually subsided, older rocks-so Werner taught-are now generally found in the mountains or at great depth below the younger rocks; this was his "Primitive Division" which included granite, gneiss, schists, slates, basalt, porphyry and other igneous and metamorphic rocks, all of which he believed to be of sedimentary origin. Younger rocks, according to Werner, were formed at successively lower levels as the water receded. Next in age he placed a "Transition System" of limestones and greywackes; still younger the so-called "Floetz Division," which included sandstone, limestone, gypsum, salt, coal, but also some basalt, porphyry and other rocks; youngest were the alluvial deposits of recent clays, loams, sands and gravel. Thus, in the Wernerian system the age of a rock was determined on the basis of its petrographic properties and the height of its occurrence relative to sea-level.Here and there these ideas survived well into the nineteenth century. As late as 1825, Charles Darwin listened to lectures by Professor Jamieson, one of the last proponents of Wernerian theories in England. The fact that entirely different kinds of fossils occurredin rocks which were regarded as contemporaneous did not worry the theoreticians.It is, therefore, noteworthy and significant that the value of fossils for the interpretation of geological events was demonstrated to the geologists by an engineer and surveyor, WiIIiam Smith, who, although no professional geologist, has often been called the "Father of English Geology." His professional work, which was mainly concerned with drainage and irrigation projects, took Smith to all parts of England, where he sometimes journeyed as much as 10,000 miles in 11 year. Smith was a keen observer and, unhampered by theoretical speculations, he noted the occurrence of fossils and collected specimens wherever he went. Before long he realized that the same kind of fossils followed each other in successive layers of rocks in much the same way in different parts of England, and soon he was able, by looking at fossils collected by other people, to tell from what...

Jan 1, 1950

By I Thomson, L D. Black, R G. Boutilier

The social license to operate (SLO) began as a metaphor for the ability of communities to stop mining projects. Soon people began to speak of levels of social license and the ability of communities to raise costs without completely stopping exploration or mining activities. Today the concept has spread to other industries and is evolving towards becoming a general management perspective on the socio-political rights and responsibilities of the corporation. The business case underpinning the SLO perspective on management is the need to assess and manage socio-political risk. For mining companies, socio-political risk has been steadily rising for several reasons, including the efforts of non-government organisations (NGOs) to pre-empt government policy options; the entry of mining companies into jurisdictions weak in the rule of law; and the weakness of global economic and financial regulation. In this perilous world beyond the comfort zone of effective government, mining companies must build their own socio-political stability by engaging directly with stakeholders to develop a strong SLO. In order to become a practical management perspective, the SLO needs to be measurable, which amounts to measuring the socio-political risks and opportunities presented by stakeholders. We present the results of efforts since 2009 to develop a globally reliable and valid measurement tool at the project and industry levels, validated in studies in Australia, Bolivia, Mexico and the USA. A factor analysis suggested four factors that mine management can address to raise their SLO level. The most chronically neglected factor involves the political right of the corporation to foster more equitable social contracts locally and regionally in both developed and developing countries. We conclude with recommended steps to earn and maintain the social license at the project and industry levels.CITATION:Boutilier, R G, Black, L D and Thomson, I, 2012. From metaphor to management tool - How the social license to operate can stabilise the socio-political environment for business, in Proceedings International Mine Management 2012, pp 227-238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By C Placzek, E Beattie, K Blake

Channel iron deposits (CID) consist of ferruginous chemical sediments, and are an unusual subset of Phanerozoic ooidal ironstone deposits almost unique to the Pilbara, where they constitute around 19 per cent of the Pilbara’s iron ore exports. These deposits occupy many of the ancestral river channels of the Pilbara region, especially the Robe River palaeochannels, incising and meandering through the Precambrian banded iron formations (BIF) of the Hamersley Group and the underlying Fortescue Volcanics.This paper explores the factors underlying geochemical variation in CID, particularly the chemical properties of goethite. The selected deposits in the western Robe palaeochannel and its tributaries show little or no secondary reworking by later water tables. There is a total absence of aluminosilicate clays with all the deleterious elements such as aluminium and silica. Instead, these are associated with the goethite mineral lattice, either within or adsorbed to the cortices of pelletoids.A thickly vegetated environment, and the presence of the Maddina Volcanics as potential source rocks for these western Robe CID is offered as an explanation for relatively high aluminium in the deposits studied, and, in turn, as the reason most parts of the palaeochannel are preserved as inverted topography.CITATION:Beattie, E, Placzek, C and Blake, K, 2017. Dirty goethite – a geochemical characterisation of some western Robe River channel iron deposits, in Proceedings Iron Ore 2017, pp 489–502 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By C A. Fleming

Gold extraction is largely driven by mineralogical factors, which often cause gold losses to various tailings. Mineralogical factors affecting gold recovery include grain size and shape, surface coating or rimming on gold particles, the presence of cyanide or oxygen-consuming minerals or preg-robbers, the presence of slow-dissolving gold minerals and the refractory nature of submicroscopic gold. Among these factors, locking of fine gold particles in sulfide, silicate and other minerals, either as visible, fine-grained gold inclusions and/or as invisible submicroscopic gold, is by far the most common factor leading to poor gold recovery in gold ore processing. This paper discusses the mineralogical characterisation of gold lost in tailings and its metallurgical implications. The techniques used in characterising the un-recovered gold are also briefly introduced.

Jan 1, 2007

By T Albinson

Mexican epithermal deposits can be broadly grouped into two types based on their contained metals, distribution, associated igneous rocks and fluid inclusion compositions. Silver-gold deposits (eg Tayoltita) mostly occur in the western part of northernMexico where host rocks consist of Eocene, intermediate composition volcanic and intrusive rocks; fluid inclusion studies indicate that mineralising fluids were <300¦C and dilute (=3 eq. wt. % NaCl). In contrast, silver-lead-zinc deposits (eg Fresnillo) mostly occur in the central part of northern Mexico where they are temporally associated with Oligocene-Miocene volcanic rocks and intrusions of felsic composition, but commonly hosted within underlying Paleozoic-Mesozoic sedimentary rocks; fluid inclusion studies indicate that mineralizing fluids ranged from 200 to 400 ¦C and were saline (=10 eq. wt. % NaCl). The distribution of these two deposit types, crosscutting major crustal sutures, and the close spatial-temporal relationships between mineralisation and magmatism, together suggest that magmatic processes were more important in the formation of mineralising solutions, as a source of both ligands and metals, than the segments of crust hosting deposits.

Jan 1, 1995

By D Kavanagh, C Michaud

"A continuous improvement initiative was identified at Kalgoorlie Consolidated Gold Mine’s (KCGM) Fimiston open pit with the goal of reducing bench turnover time and increasing shovel digability by improving fragmentation around previously mined-out stopes. In the past, a higher number of blasts than normal would be required to get through a single excavation area where stopes were present. This is due to the limited reach capability of the drilling fleet from safe ground into restricted areas requiring the drilling of the shot to be done in a staged manner. In addition, the holes that were able to be drilled in the area did not remain open long enough to be loaded with explosives as a result of the poor ground conditions surrounding the stopes.Over the last 18 months, KCGM has trialled drill additives to improve blasthole stability, as well as introducing a remote drill rig allowing holes to be drilled in areas previously inaccessible by manned drill rigs. This has resulted in improved penetration rates in bad ground conditions, improved drill hole stability, better shovel digability, and an overall reduction in bench turnover of at least ten days on the benchmarked 126 days average per bench. KCGM is now in the final stages of the improvement project with the installation of a drill monitoring system on the fleet to allow live data transfer back to the office for analysis, as well as providing improved accuracy on drill holes in restricted areas.Citation:Michaud, C and Kavanagh, D, 2016. Reducing Bench Turnover Time and Improving Shovel Digability, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 19–27 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By C Jia, J Graindorge, L M. Olssen

Picking up abandoned mining tenements and looking to recover remnant resources around old operations is an opportunity that comes with its own challenges and risks. Reliance on information released to government departments (such as the Department of Mines and Petroleum (DMP) in Western Australia) by the previous owners, can compound the risk.This paper explores Alto Metals Ltd’s Lord Nelson and Lord Henry deposits and surrounds near the town of Sandstone in Western Australia. The Lord Nelson and Lord Henry open pits produced around 2 Mt of ore for over 250 koz of gold during production between 1999 and 2010. There has been no further work carried out in the area between 2010 and 2016. The deposits are open at depth and along strike.Alto Metals picked up the tenements in 2016 and has subsequently re-estimated remnant resources around Lord Nelson and Lord Henry, and publicly reported updated Mineral Resources in accordance with the JORC Code 2012.All of the information was manually compiled from data released to the DMP and annual reports. This paper highlights the challenges and risks arising from this data compilation, geological interpretation, re-estimation and classification process, together with future opportunities and challenges for further developing the area.CITATION:Olssen, L M, Graindorge, J and Jia, C, 2017. Starting from scratch – defining remnant resources from publicly available data: a case study from the Lord Nelson and Lord Henry gold deposits, in Proceedings Tenth International Mining Geology Conference 2017, pp 175–188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

Total mechanisation in the Western district of New South Wales is quite a recent addition to productive methods in that State, for it was only in 1940 that the first colliery was equipped for this method of winning coal. Now almost all mines either are totally mechanised or are planning to get their coal by these means.This marked change in recent years is explained by the salient features of the industry's history. Collieries in New South Wales had generally been subjected to low selling prices forced on them by over-production and severe competition. Little money was available out of profits to purchase machinery, and returns on capital were so poor that inducement to invest money in the industry was nonexistent.The second world war brought price fixing at the already low prices. It was not until the post-war period that there has been any inducement to mechanise.Much credit for mechanisation can be given to the Joint Coal Board, a government body formed in 1948. Pursuing a broad plan for the rejuvenation of the industry, this Board, purchased large quantities of machinery for use in, mines under hire-purchase agreement. These agreements encouraged machine mining, and this fact, together with the ensuing production economies, has improved the financial position of the industry.The Board has also been instrumental in the granting of increases in the fixed price of coal, so that the industry has been given an even greater boost in the direction of mechanisation.

Jan 1, 1954