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THE Broken Hill mining field, approximately 31 miles in length, is at present being exploited by seven companies, viz. : North Broken Hill Limited, Junction North Broken Hill No Liability, Broken Hill Proprietary Block 14 Company, Broken Hill ProprietaryCompany Limited, Sulphide Corporation Limited, Broken Hill South Limited, and Zinc Corporation Limited.The variation in size and shape of the ore-bodies in the mines of these companies, together with the many alterations in pitch and dip, necessitates differences in methods of mining, each company working out its problem in its own particular way.In the matter of chute construction for the handling of the ore broken in the stopes, each mine belonging to the above companies has adopted a style particularly its own, though it may be said that one or two of the types approximate very closely to each other, slight minor differences only being noticed in the design. It is the purpose of this paper to give a brief description of the principal types of chutes now in use in th,e various mines on the field, and in doing so they may roughly be classified into three groups, viz:1. Bulk Chutes, 2. Circular Chutes, 3. Square-set Chutes.The Bulk type of chute is used in the North and British mines of the North Broken Hill Limited, the Central and Junction mines of the Sulphide Corporation, the South Blocks mine of the Zinc Corporation, and the Block 14 mine.The Circular type of chute is used by the Broken Hill South mine and the South Blocks mine.The Square-set chute is used in the Proprietary mine, the Junction North mine, and occasionally in other mines where the square set method of mining is a necessity, and more particularly as mullock passes.

Jan 1, 1925

The interaction of flotation collectors with sulfide minerals takes place at the solid - solution interface. The electrochemistry of the processes which affect this interface are discussed. The interaction of xanthates with sulfides is an electrochemical process, xanthates being electro-oxidised to chemisorbed xanthate and dixanthogen. The role of oxygen is to provide a cathodic process to allow the anodic oxidation to occur. The hydrophobic condition of the mineral surface is brought about by the presence of the oxidised xanthate species. The action of reagents which can activate or depress the flotation of sulfides is discussed briefly.

Jan 1, 1971

By B Nielsen, H Lehto, J Rohleder, C Robben

Sensor-based ore sorting is being increasingly used to reduce the amount of low-grade and waste material processed in mineral concentrators. This type of preconcentration provides bottom-line benefits to users by reducing the amount of energy, water and consumables, as well as reducing capital cost. Existing operations can increase metal production, while previously uneconomic deposits and low-grade stockpiles can also be exploited. The technology can also be used to separate ore types for selective processing. The path to implementing sensor-based sorting may include:• geometallurgical evaluation• first inspection testing to investigate sensor response• bench-scale testing where sensor selection is not obvious or for difficult applications• performance testing in full scale sensor-based sorting machines• larger scale site-based piloting with a temporary semi-mobile plant installation. Sorting requires material to be suitably prepared and presented to the machines and typically this consists of crushing and screening to limit top size and optimise liberation. However, where material streams are suitably sized and prepared, additional equipment may not be required (e.g. the sorting of semi-autogenous grinding (SAG) Mill pebble streams).This paper presents a case study of economic upgrading of gold ore, by preconcentrating with sensor-based ore sorting. The case study examines sorting amenability, test work, the feasibility study through to implementation, with associated flow sheet development. The development process is analysed and evaluated with a view to rationalising the process for development of future projects. In addition, limited financial modelling based on expected results is shown to illustrate the benefit to the operation.CITATION:Nielsen, B, Rohleder, J, Lehto, H and Robben, C, 2017. Sensor-based ore sorting to maximise profit in a gold operation, in Proceedings MetPlant 2017, pp 131–146 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By L Barrere, J P. Sykes, A Trench, R S. Davies

Western Australia (WA), alongside Brazil, has remained at the forefront of the global seaborne traded iron ore market for over 40 years. Despite this apparent stability and strong market position, WA continues to face strong external international supply-side competition, mainly from Brazil, but also periodically from often marginal, non-traditional sources of iron ore. Additionally, WA iron ore supply has undergone significant decadal change internally, both of an evolutionary (brownfields expansion) and revolutionary nature (major new greenfields projects). Since 2006, a new generation of WA-focused iron ore explorers, developers and producers have emerged.The majors, BHP Billiton and Rio Tinto, have expanded mine production to record levels and the Roy Hill project is now approaching nameplate capacity. Fortescue Metals Group (FMG) is, however, the largest new market entrant of the last decade, delivering upon their vision of becoming the ‘new force in iron ore’. Unlike most of the other new WA market entrants, FMG’s operations are substantive. Most of the other smaller, new WA iron ore miners have struggled during the period of falling prices, though it is worth noting that collectively they have made a material supply-side impact during the price boom – typical of marginal supply. Finally there have been some contributions from new magnetite projects, however, the delivery and economics of these projects have not met expectations.In this paper, we touch briefly upon the key global market changes of the last decade, namely China-driven demand growth and the changes to the pricing mechanisms for iron ores – before reviewing the rise in WA iron ore supply in response to these markets. We finish by focusing on the most significant WA-focused supply-side development of the last decade, the rise of FMG as a major new supplier and the strategic situation that facilitated its rise. The unprecedented China-led rise in iron ore prices felled many traditional barriers to market entry into an oligopolistic industry, allowing many new market entrants (in WA and around the world). However, the downturn in iron ore prices resurrected these barriers to entry, with only FMG (thus far) breaking the entry barrier with significant scale. Difficult corporate decisions have been forced upon the smaller WA iron ore miners who, in some cases, will now struggle to further expand, or indeed continue to operate in the longer run.The changes that have taken place over the last decade of WA iron ore production hold insights for other emergent mineral commodity exports from the state. Successful market entry, even when industry barriers are high, does not always require an immediate low-cost production assumption alongside a strong balance sheet. FMG could see a new market, within an established commodity market, target an appropriate and new product at it, overcome temporarily-felled barriers to entry in infrastructure and finance, then innovate and aggressively cut costs ensuring it was behind the barriers to entry when they rose again after the price boom.CITATION:Barrere, L, Trench, A, Sykes, J P and Davies, R S, 2017. New generation Western Australian iron ore – strategic insights far beyond the Pilbara?, in Proceedings Iron Ore 2017, pp 375–386 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By N J. Welham

This paper reports on an innovative professional development program for school science teachers run collaboratively between the Centre for Sustainable Resource Processing and Murdoch University. Ultimately the initiative aims at increasing the pool of school students with strong science and mathematics backgrounds while highlighting the challenging careers available in the mineral resource sector including the gold industry. The program is unique in that it seeks to develop a network of science teachers who may participate in a series of workshops, short courses and tours over several years. The objective is to raise secondary school studentsÆ awareness of potential careers within the minerals sector by exposing teachers to a real life, hands-on look into the mining and minerals resource industry. Though the program includes the breadth of the resource processing sector, the potential value to gold processing is in developing a greater pool of potential employees. The initiative allows teachers to develop a better insight into the practical applications of the theoretical sciences they are required to teach. The evolution of the program from the first trials with Western Australian teachers to the introduction of the initiative to Queensland teachers are reported on. Additionally, the results of a pilot study involving 40 participating teachers are described. This study used a questionnaire and follow-up interviews to gain quantitative and qualitative feedback from teachers. There is evidence that the professional development program has resulted in teachers acquiring a new found appreciation for the application of the fundamental chemistry and physics they teach within the school curriculum. Also reported are associations between teacher participation in this professional development program and changing attitudes towards the industry in a positive way. Finally, there is some indication that these positive teacher attitudes may result in their students developing a better understanding of the diversity and availability of career paths within this industry.

Jan 1, 2007

The nature of the specialty glass and ceramic business magnifies the dependency of the ultimate product on the unique properties of their raw materials used to make them. This dependency has implications in the management of risk in the supply process which requires a special procurement organization and program commitment to be successful. The Coming system of managing critical materials and factors in development of alternate new suppliers and products is discussed.

Jan 1, 1989

Inhibition of Bubble Coalescence by Salts and Sugars

Sep 13, 2010

By R J. Holmes

An accurate knowledge of the chemical, mineralogical and physical characteristics of ores and mineral products that are mined, processed and traded is crucial to effective resource utilisation, plant design, process optimisation and finally quality control to ensure that contract specifications are met. However, all too often the responsibility for sampling is entrusted to managers and personnel who do not fully appreciate the significance and importance of collecting representative samples for analysis, and everyone seems satisfied as long as some material is collected and returned to the laboratory for analysis. Furthermore, sample stations incorporated into the design of new plants are often the first casualties when cost cutting exercises commence. This needs to change, because there is little point in accurately analysing samples if they are not representative in the first place. The resultant analyses can be next to meaningless and the effort taken to analyse such samples is to a large extent a waste of time and resources.Ultimately, a poor knowledge of the characteristics of ores and mineral products limits the ability of mining companies to optimise the life of ore resources and plant performance, and failure to meet final product specifications can have disastrous consequences, including price penalties and more seriously loss of sales contracts. It is high time that sampling is given the attention it deserves as the first critical step in the quality measurement chain.CITATION:Holmes, R J, 2013. The importance of sampling in the mineral industry, in Proceedings MetPlant 2013 , pp 34-49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By S Thomson, M Lovitt, T Purvis, C te Kloot, T Nguyen, Z Liu

Ernest Henry Mine (EHM), located in north-western Queensland, is an underground copper/gold sublevel caving operation currently producing over 6 Mt/a of ore. The mass mining method of sublevel caving (SLC) used at EHM involves systematically blasting a series of uphole rings in parallel ore drives and drawing the broken ore using a top-down approach. Each ore drive contains multiple precharged rings to prevent having to charge in close proximity to the brow of the previously fired ring; however, the current initiation system still involves ‘hooking up’ all detonator lead cords of the first precharged ring. The unstable nature of a rill and working close to a brow presents hazards to personnel completing the hook-up process. There is also a business risk of ore loss when damaged ground support completely prevents access to the next precharged ring. If the hook-up step could be eliminated, the risk to personnel and the business would be significantly reduced.EHM engaged Orica Mining Services in 2016 to trial their WebGenTM 100 – wireless electronic blasting system (WEBSTM) for the first time in an underground mining environment. Having successfully signal-tested the equipment, two test holes were initiated, followed by a single production ring and then multiple production rings. In total, 30 production rings were successfully fired underground at EHM in 2017. To do this, WEBSTM was successfully integrated into EHM’s current charging and firing process, resulting in no business delays or loss to production. None of the 30 rings required hooking up and all were initiated from the surface with no personnel underground. A high level of ownership from all personnel involved ensured the trial was a success, and provided scope for wireless detonators to be used successfully on a large scale – both at EHM and other sublevel caving operations. WEBSTM is now a proven example of technology that can be used to improve safety in the mining industry, through eliminating the need for personnel to work in hazardous areas.CITATION:te Kloot, C, Liu, Z, Purvis, T, Thomson, S, Lovitt, M and Nguyen, T, 2017. Improving safety through technology – Orica wireless electronic blasting system trials at Ernest Henry Mine, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 39–50 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

The Porgera gold deposit is an epithermal gold base-metal deposit located in the Enga Province of Papua New Guinea. Gold-silver-sphalerite-galena-pyrite mineralisation is related to stocks and dykes of dioritic composition which have intruded a series of folded marine sediments, mainly shales and siltstones, often with calcareous and carbonaceous horizons, of middle Jurassic to middle Eocene age. The most intensely mineralised zone is at Waruwari Hill, where the mineralisation occurs predominantly as massive mixed sulphide veins, and less frequently as quartz-chlorite veins and as disseminations. Mineralisation occurs in all rock types and several phases of mineralisation have been recognised.

Jan 1, 1980

Implementation of Fine-Screening in Preparation of KGHM PM SA Sandstone-Carbonate Copper Ore for Flotation

Sep 13, 2010

A paper presenting an overview of legislative and best practice approaches to the management of OHS&E and business risk for Australian tunnelling operations. Best practice can be achieved in Australian tunnelling through ærisk awarenessÆ by decision-makers and line personnel. This will identify problems before they occur and lead to implementing controls appropriate to avoiding loss throughout the life cycle of the underground opening. The author draws on legislative approaches from all Australian states together with practical experience from risk management and risk engineering work from six recent tunnelling projects. This describes a process that:commences with concept risk assessment,involves quantification of major hazards,conducts assessments of operating risks, andleads to implementation of an integrated management system that keeps construction activities connected with the controls identified in the design and planning phases and minimises the losses sustained as a result. Key points addressed include:where the industry is going with respect to risk û methods and considerations,how tunnelling risks are perceived by the industry and legislation,how tunnel constructors and owners can minimise exposure by using proper risk engineering ætoolsÆ, andreflections on best practice methods for transferring knowledge from designers to contractors/operators.

Jan 1, 2008

By B B. Beamish, J Theiler

Current spontaneous combustion index parameters such as SHT, CPT/RIT and R70 self-heating rate all have deficiencies that need clarifying from a risk management perspective. In some instances they can produce a false negative evaluation and in others they can produce a false positive evaluation. These tests all use a relative rating scheme that does not provide any indication of the time it takes for a spontaneous combustion event to develop, nor do they consider the moderating influence of moisture present in the coal on self-heating rate in the low temperature oxidation region. This is viewed as a major deficiency since the true self-heating behaviour of broken coal is primarily a function of time that is governed by the interaction of the initial boundary conditions (initial ambient temperature and moisture state) with the reactivity of the coal (both intrinsic coal reactivity and accelerated self-heating from reactive pyrite if present). The current index tests are also not appropriate for assessment of coalmine immediate roof and floor rocks.CITATION:Beamish, B B and Theiler, J, 2017. Recognising the deficiencies of current spontaneous combustion propensity index parameters, in Proceedings Australian Mine Vent Conference 2017, pp 113–118 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By A Rojc, J Ronaszeki, C Smith

Nuclear logging was tested for the in situ determination of Fe, Si, and Al in iron ore blastholes with field tests at the BHP Billiton Iron Ore, Mount Waleback Mine. Prompt gamma neutron activation analysis (PGNAA) was used to determine percentages of Fe and Si while natural gamma logging was employed for the determination of Al. The accuracy given by nuclear logging is comparable to the accuracy provided by the laboratory analysis which was determined by taking the average of four samples collected from the cuttings deposited on the surface around the perimeter of a drill hole. The work also indicated that there is a chance of determining Al by PGNAA.

Jan 1, 2002

By T S. Giraudo

The Macraes Gold Project, operated by GRD Macraes Limited, engaged GRD Minproc Limited to assist with the evaluation of a pressure oxidation circuit, this being the key component of a recovery enhancement project. The initial study gave sufficient confidence in the process to enter into project execution. GRD Macraes Limited was the first company to license Newmont Mining Corporation's pressure oxidation technology, which aims to improve gold recovery from the carbonaceous sulfidic flotation concentrate. This paper outlines the fundamental chemistry of the process followed by a description of the plant that was ultimately installed. A summary of the commissioning is given together with an overview of the production results to date. The project ramp-up was rapid, with design temperature and throughput being achieved within days of hot commissioning. Gold recoveries have exceeded expectations, improving from around 70% prior to the installation of pressure oxidation to above 84%. The project has increased the nominal gold output at Macraes from 120,000 oz/y to 170,000 oz/y. On-going plant optimisation for process parameters is discussed, giving rise to flexibility in gold production, with key controlling parameters exceeding design.

Jan 1, 2000

The Rosebery and Hercules mines, situated in the Rosebery-Williamsford district in western Tasmania, have a history of production dating back to 1896-7, although full scale production did not commence until 1936, following the development of a satisfactory process of selective flotation (Hall, Cottle, Rosenhain and McGhie, 1953). The mineral composition of the Rosebery zinc-lead ores was first described in detail by Stillwell (1934). The Hercules ore is generally similar, but as yet no descriptions of it have beenpublished.Since Dr. Stillwell's paper appeared, the management of the Rosebery and Hercules mines has from time to time submitted a number of interesting mineral specimens to C.S.I.R.O. Mineragraphie Investigations. Examination of these specimens brought to light eight minerals, some relatively uncommon, not previously recognized in these ores.They are cassiterite, molybdenite, stannite, electrum, meneghinite, boulangerite, pyrargyrite and pyrrhotite. Some of the specimens are also rich in tetrahedrite and gold. In addition each of the other ore minerals described by Stillwell, viz. pyrite, sphalerite, galena, bournonite, chaleopyrite and arsenopyrite, was detected in one or more of the specimens examined during the present study. The principal gangue minerals were found to be quartz, manganiferous carbonate, sericite and barite, agreeing closely with the observations of Stillwell.The present study was based on the examination of the following eight specimens.

Jan 1, 1960

By Olliver J. G

Over 400,000 tonnes of kaolin, sillimanite, mica, kyanite, feldspar and rutile have been mined from the unique Williamstown orebodies since their discovery in the early 1900's. Numerous companies; both large and small were associated with the early development of these deposits but since the formation of Australian Industrial Minerals in 1947, this company has been the only significant producer. A combination of mining and management problems almost forced closure of the mine in the late 1970's but this was averted by a changed attitude towards mine planning. Mine development is now based on detailed geological and technical investigations, exploration for additional ore reserves is being conducted and laboratory and pilot scale studies are being undertaken to utilise both low grade ores and waste materials. The professional approach to mine and market development will ensure that Williamstown mineral products will continue to be available for many years.

Jan 1, 1989

Properties of coal which are significant in relation to preparation for carbonization and conversion are reviewed, and existing coal preparation technology which has been used for production of cleaned coal of suitable ash content and petrographic composition for carbonisation, pyrolysis, hydrogenation and similar processes is described. Possibilities for application of this technology to some Australian coal seams is examined briefly. It is concluded that further survey work is required related to the optimization of selective crushing and concentrating operations, with the aim of maximizing production of quality products for carbonisation, etc mainly from Australian seams with only moderate coking characteristics.

Jan 1, 1980

The Performance of Benzyl Arsonic Acid as a Collector in the Flotation of Wolframite and Cassiterite Slime

Sep 13, 2010

By B Watson

The ConSep ACACIA Reactor is a device, which utilises a high intensity cyanidation process to achieve very high, usually near total, recovery of gold from gravity concentrates. The process utilises a fluidised bed and a chemical oxidant to enhance the gold dissolution kinetics to the point where the bulk of the dissolution occurs in a few hours. For convenience and security, most plants operate a 24-hour turn around. The product from the process is in the form of cathode gold ready for smelting by traditional means. The ConSep ACACIA Reactor performs a two-fold role. Firstly it increases gravity gold production, leading to a decreased CIP feed grade. Secondly, it removes slow leaching components from the plant leaching circuit. This two fold benefit leads to the following efficiencies: enhancement of the dissolution kinetics; enhancement of the adsorption kinetics; reduction of the gold load reporting to the carbon; a significant reduction of the ægold in circuitÆ lockup; and removal of slow leaching entities which can also result in a lowering of the required cyanide concentrations in the leaching circuit and a subsequent reduction in overall cyanide consumption. The above benefits are discussed in this paper, with a particular focus on the ConSep ACACIA ReactorÆs role in removing slow leaching components, with data generated over a 21-month period. Improvement in overall plant recovery via removal of slow leaching gold species is achieved in two ways. Firstly, some of the slow leaching entities, successfully leached under intensive cyanidation, are not always fully leached under plant conditions. This results in a lowering of the solid tailing. Secondly, the faster leaching kinetics achieved in the plant as a result of the removal of slow leaching entities results in faster and more complete adsorption of the dissolved gold onto activated carbon. This results in a lowering of the solution tailings. The construction and operation of the ConSep ACACIA Reactor is simple. Apart from the reactor body, which is a proprietary design, all components of the system are æoff the shelfÆ or specific to the siteÆs requirements. In operation of the fully automated version, a PLC controls a series of valves and pumps but except for a daily changeover process the only operating component for the bulk of the time is a relatively small solution pump. The process can be totally automated giving the security of a æhands freeÆ concentrate handling process up to the point where the product is presented as cathode gold. The ConSep ACACIA Reactor was developed by Anglogold Australia (formerly Acacia Resources) for Union ReefÆs Gold Plant and has been in production since February 1999. It has proven to be a low cost, high recovery, mechanically reliable method for the processing of gold concentrates. Such has been the success of the plant, as of June 2003 there are eighteen full installations of the processing plant installed at mines owned and/or managed by Anglogold, Newmont, Placer Dome, Independence (formerly Lonrho), Sons of Gwalia and Harmony.

Jan 1, 2003