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By A Parbhakar-Fox, B G. Lottermoser

Management of solid mine wastes, particularly waste rock, requires careful planning to reduce the likelihood of sulfide oxidation, and generation of acid rock drainage (ARD). Waste management strategies must focus on obtaining a thorough understanding of the environmental characteristics of future waste rock materials. In this study, a waste management strategy for characterising underground waste rock was developed at a polymetallic underground mine in western Tasmania to determine which materials were appropriate for surficial placement. The criteria for surficial placement set by the regulator were that materials had to be non-acid forming and non-metalliferous. A range of cost-effective field-based tools, mineralogical assessments and mineral chemistry techniques were used on a suite of representative drill core material to determine an appropriate waste management strategy. Ultimately, a modified geochemistry–mineralogy–texture–geometallurgy (GMTG) approach was designed, whereby geoenvironmental focused logging and simple prescreening tools such as paste pH and sulfur analyses were used at stage-one; routine acid base accounting and leachate tests at stage-two; and validation tools including X-ray diffractometry and laser ablation inductively coupled plasma-mass spectrometry (ICPMS) at stage-three. This approach should be considered for other mine sites at early and operational life-of-mine stages with similar deposit characteristics, to ensure correct screening and placement of potentially hazardous waste materials in suitable above-ground waste repositories or mined-out mine sections.CITATION:Parbhakar-Fox, A and Lottermoser, B G, 2017. Effectively linking mining geology with waste management – a case study from western Tasmania, in Proceedings Tenth International Mining Geology Conference 2017, pp 117–126 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By R Harding, T Hunt

For the past 120 years, Portland cement manufacture has been undertaken on the shores of the Whangarei Harbour in northern New Zealand. Through a serendipitous conjunction of geo-chemistry, the argillaceous marl found on Limestone Island in the harbour and Tikorangi Hill provides a perfect mix of the various elements required for strong and durable cement. Golden Bay Cement, and its predecessors, have been the guardians and managers of the use of these minerals. As the demands of the concrete industry have increased, so have the needs of the manufacturing process. Careful mapping of the resource at both Portland and Wilsonville Quarries has been undertaken. This has allowed the Company to change the Quarry operation from a purely volume basis to one of selection and blending of constituent minerals. Within the manufacturing process, change has also been introduced. Analytical techniques, using x-ray fluorescence spectrometry, microscopy and the application of modem data collation, has allowed fine tuning of the process. The Company now produces an increasing diverse range of products for both the domestic New Zealand market and exports to various South Pacific countries. This paper discusses the processing of limestone and æcement rockÆ into cement clinker, an intermediate synthetic mineral ground into cement. It examines control and blending regimes, and some methods used in determining process efficiency. An important technique ærediscoveredÆ has been the application of microscopy to clinker.  Examination of the major silicate minerals enables interpretation of the kiln processing and feedback to process operators. It also enables a prediction of indicated performance when ground into cement. Examples this paper give an insight into the use of minerals from Northland in some of the more important construction projects in modem New Zealand.

Jan 1, 1999

By C MacDonald

There are many technologies available today in terms of fire and life safety in road tunnels. So many in fact that it is becoming more and more difficult for clients and contractors alike to determine what they want and what they need. From a clientÆs perspective, fire and life safety is about protection to its infrastructure and to the public at large. Conversely, the contractor is looking to meet its æfit for purposeÆ or ædeem to complyÆ requirements in the most economic and practicable way. Practices regarding fire and life safety in road tunnels have undergone a degree of transformation during the last decade or more throughout the world. This transformation has largely been driven by a series of catastrophic accidents such as the major fires in Europe including the Mont Blanc Tunnel, Tauern Tunnel, Saint-Gothard Tunnel, and now most recently in the CityLink Tunnels in Melbourne. International guidelines produced by organisations such as the Permanent International Association of Road Congresses (PIARC), the European Union, the International Tunnelling Association (ITA) and the US National Fire Protection Authority (NFPA) now provide clients, owners and designers with the tools required to define and specify the required fire and life safety systems in road tunnels. The majority of these tools are based on risk assessment and risk management. Recent road tunnel projects within Australia, however, have not referred solely to such guidelines. Clients have opted to prescribe different or additional fire and life safety requirements within the projectÆs technical specification documentation (project requirements), leaving designers and contractors with little room to implement alternatives or substitutions. Further, these project requirements are largely dictated by practice established on previous road tunnel projects within Australia. This paper looks at the current international guidelines and practices and undertakes a comparison with the EastLink tunnels in Melbourne and other road tunnels within Australia and makes assessment on whether Australian methods are the most appropriate for clients and contractors alike. Focus is directed to the key elements of fire and life safety such as:traffic envelope, barrier arrangements and emergency walkway provisions;deluge systems;drainage systems;fire rating requirements;tunnel ventilation systems;cross passage provisions;fire safety assessment;critical intelligence systems including help phones, CCTV, incident detection, tunnel signage, etc; andexternal tunnel control systems.

Jan 1, 2008

A New Technology of Applying SLon-2500 Magnetic Separator to Recover Iron Concentrate from Abandoned Tails

Sep 13, 2010

Development of Grindability Tests Based on Direct Measurement of Energy Nowadays, for the characterisation of the grindability different grindability indices - Bond-work index (Wi), Hardgrove Grindability Index (HGI) or Zeisel specific grindability (Wt) - are used. Generally, the grindability tests are carried out under relatively simplified circumstances, in a special dry batch mill with defined feed size material until prescribed conditions are reached at room temperature. However, in the fine- and ultra fine grinding, which is a frequent task (fly ash, tailings, alumina, etc), a fine material (<50 - 200 ¦m) is usually ground down to the few micrometers. The conventional grindability testing methods and apparatuses (Bond-, Hardgrove-, Zeisel-processes) for their determination, although, are not suitable directly to measure the grindability of such fine materials, since the maximal particle size of the feed material (0.5 - 3 mm) to be tested is much higher. One of the important goals of the research carried out in our Institute was to develop the novel grindability testing methods, which are suitable for the fine and ultra fine grinding, and additionally provide the possibility for the fast determination of the grindability. In order to realise the above aim the conventional Bond- and Hardgrove- mills were modified in order to directly measure the grinding work. In particular, the Hardgrove-mill was equipped with a simple torque-meter (load cell). The Bond-mill was rigged with a digital electric power measurer. The systematic experiments were carried out parallel in both mills using the conventional and the developed methods. Finally the results of both were compared. The measuring results have proved that the Bond-work index can be determined based on the developed methods. The new grindability testing methods were applied successfully in several industrial research tasks for the determination of the specific grinding energy and the Bond-work index. These methods can be also used in the industrial practice for the control of the grinding process.

Sep 13, 2010

Consents Required for Overseas Persons Overseas Investment Regulations 1974 Foreign investment proposals must be reviewed by the Overseas Investment Commission to ensure that these are in accord with national interests. Consent must be obtained from the Commission for: 1. New investment proposals which include: a. An overseas person acquiring 25 per cent or more of any class of share in a company. b. A New Zealand company issuing shares to an overseas person where this will result in that person owning 25 per cent or more of the company. c. An overseas person acquiring business assets for consideration in excess of $100 000. d. An overseas person commencing business in New Zealand. 2. Borrowing in New Zealand: An overseas person must obtain consent to raise funds in excess of $300 000 in New Zealand. 3. Borrowing Overseas: New Zealand incorporated companies must obtain consent to borrow overseas. Current policy is borrowing will be approved where the loan is for a specified fixed term of one year or more.

Jan 1, 1982

By B Hiebl, J Martens, L Petzold

A research team at the Iron and Steelmaking department at Primetals Technologies has established new upgrading measures for improving the efficiency of the beneficiation process in ironmaking plants, relying largely on pre-existing equipment. After the upgrade, the iron content in the final iron ore concentrate was shown to be significantly higher. Remarkably, the costs for employing the respective measures are surprisingly low.This case study is based on a Kazakh iron and steel producer, whose beneficiation process is currently generating a magnetite concentrate with a final iron content of 65.65 per cent. The study shows that the implementation of Primetals Technologies’ intelligent modification measures to the current beneficiation process, the realisation of more effective dewatering, and the utilisation of an innovative binder lead to an increased iron content in the resulting pellets, reaching a concentration of 69.17 per cent (iron ore concentrate) and 66.5 per cent (pellets).The current operation consists of three closed circuit grinding stages, four stages of low intensity magnetic separation, vacuum disc filters and straight-grate pelletising. By dividing the slurry after the second stage of grinding and the third stage of low intensity magnetic separation, it is possible to divert the more iron-rich fines before they would enter the third grinding stage and the fourth stage of magnetic separation. This then reduces the load on the existing third stage ball mill. Afterwards, the ground material is treated in an additional low intensity magnetic separator and mixed with the previously diverted fraction of the fines. An improved filtration procedure, combined with the application of a highly sophisticated binder, further reduces the amount of additives needed, so that a genuine direct reduced (DR)-grade iron concentrate is produced as a result.All laboratory, pilot and pelletising test work was executed at Primetals Technologies’ laboratories in Austria.CITATION:Martens, J, Petzold, L and Hiebl, B, 2017. Enabling iron ore concentrate for the production of direct reduced iron with pre-existing beneficiation lines, in Proceedings Iron Ore 2017, pp 227–232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By S Speed, N Corlis, A Goldstone, G N. Browne, M Fitzpatrick

In 2005, Solid Energy New Zealand Limited obtained non-notified consent for the disposal of 1Mt of coal ash at the Rotowaro minesite, forming part of a coal supply agreement with the Huntly Power Station. A non-notified resource consent was sought which necessitated that environmental effects be shown to be æless than minorÆ, and resulted from robust science and a pragmatic approach to design. As part of the assessment of environmental effects, there was a need to understand the effects of boron concentrations on aquatic organisms (ie algae, plankton, plants and invertebrates) in the receiving environment. Boron is a naturally occurring element that is found in the form of borates in the oceans, sedimentary rocks, coal, shale, and in some soils but Waikato coals and ashes have particularly high boron content. Boron is an essential micronutrient for higher plants with interspecies differences in the levels required for optimum growth. As aspects of the ANZECC (2000) derived boron limits are based on toxicity of aquatic algae and plants to boron it was important to assess these components in the environment. The effects on the receiving environment of the Awaroa Stream were assessed using predicted water chemistry and comparing actual boron concentrations in a comprehensive and multifaceted reference-condition approach of catchment ecological indicators. In addition a toxicological-based assessment of boron and a re-calculation of the ANZECC trigger levels were undertaken and applied to the ecological indicators. The reference-condition approach revealed that habitat and overall water quality attributes at and between sites was more influential in determining the aquatic biotic communities than boron concentrations alone. There was no evidence of any gradient of changes in ecological indicators with changing boron concentrations, nor evidence of any residual effect of high historic boron concentrations on the aquatic biota.

Jan 1, 2006

As part or a programme to raise lead smelter capacity from 65.000 to 140.000 tons bullion per annum. one new 1000 sq. ft. updraught area sintering machine replaced eight small downdraught machines.The metallurgical specifications were based on and laboratory tests at Mount Isa. Existing practice filtering concentrate as part of the charge preparation system and discharging wet filter cake to mixing was retained. This dictated a hot return fines circuit to maintain the required feed moisture content at low return sinter ratios.The engineering specifications provided for cenlralized control of plant and process, minimum operating labour, high plant availabi;lity and highest standardsof hygeine. Crushing and conveying capacity was set to cater for the most optimistic level of sintering capacity.On start-up a number of major engineering and hygiene problems became apparent, in addition to normal teething troubles. These problems have largely been overcome and reliable operation. at less than optimum production rate is now being achieved.

Jan 1, 1968

By J Mauk, J Rowland, S Rabone

Most epithermal Au-Ag deposits in the Hauraki Goldfield are hosted in late Miocene andesites. Broken Hills is an exception, being one of the few economic deposits hosted in rhyolite. Investigation of Broken Hills provides the opportunity to collate structural data that may be compared with that collected from andesite-hosted deposits in order to evaluate the importance of rock type on vein development. The rhyolite host rock at Broken Hills is strongly flow-banded, but this anisotropy does not appear to affect the orientation of mineralised structures. There is a range of structures at Broken Hills: veins, faults, fractures, and large breccia pipes. Veins generally strike north-south, with localised changes in strike and thickness. Slip vectors determined from striations indicate near pure dipslip on the main lode, indicating an extensional tectonic setting. The orientations of vein deflections are parallel to slip vectors. This correlation is common in modern extensional fault arrays where fault growth and linkage produces subvertical deflections in fault orientation (eg TVZ). There are three main types of breccias: 1. Primary breccias related to rhyolite emplacement. 2. Jigsaw type secondary breccias that are that developed during the life of the hydrothermal system. 3. Breccia pipes. Broken Hills was a dynamic epithermal mineralising system.

Jan 1, 2003

By R G. Richards

The Australian glass sand industry produces some 2.8 million tonnes per annum of silica sand, of which about 2.0 million tonnes are exported and the rest is for the domestic market. Approximate production rates for each Australian state are listed. The variety of processing methods used in the currently exploited deposits reflects the size, location, and characteristics of the various deposits and the requirement of the end market/s. The industry uses to a large extent equipment developed for the separation of mineral sands, particularly as it applies to low grade heavy mineral deposits, where low cost, high capacity and metallurgically efficient equipment has proved eminently suitable for the production of the low value glass sands. The requirements of the domestic market, as well as those of the present and potential export markets are discussed covering quality requirements, distribution channels and other factors critical to success.

Jan 1, 1990

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

A search for the keyword nano reveals that it has not made a significant entry into the mineral processing research literature. In contrast, the terms micelle, colloid, interface, and monolayer are well established there. By considering nanoscience as colloid and interface science at the nanoscale, it is claimed that several previous and current investigations in the broad field of mineral processing fall under the umbrella of nanoscience. Several examples from hydrometallurgical processing systems (invisible gold and activated carbon in gold extraction; monolayers, reverse micelles, and microemulsions in solvent extraction; nanobiofilms and nanoparticles in biohydrometallurgy) are highlighted in support of this view.

Sep 13, 2010

By D Garcés, M Meléndez, R Castro, E Viera

Enhancing the understanding of gravity flow in caving operations is a key factor in the design, operation and success of caving methods. Consequently, much research has been performed to increase knowledge about gravity flow. Many valuable theories have been gained from different research approaches, which include physical modelling, numerical modelling and a limited number of full-scale tests. Recent advances in technology have allowed Codelco Chile to carry out trials using Smart Markers technology. This technology was used in Esmeralda mine’s Block-2 at El Teniente mine from August 2012 to January 2015. This paper aims to determine the characteristics of the extraction zone and obtain the data that will allow greater understanding of gravity flow for design and draw control purposes.The collected data from recovered markers were analysed using a linear interpolation of both the initial position of the markers and drawbell accumulated drawn tonnage. For each drawpoint in the trial, the regularity or irregularity of flow was analysed based on the recovered markers and the drawn tonnage. Correspondingly, the relationship between flow characteristics and observed fragmentation in drawpoints was analysed. The gravity flow of the Smart Markers revealed that current drawpoint spacing provides the interaction conditions of adjacent flow zones. However, it is possible to increase the drawpoint spacing while allowing caved rock to be extracted from the major and minor apexes.The results of this research also verified that full-scale test data are the predominant factor in the production level design and production control at El Teniente mine.CITATION:Garcés, D, Viera, E, Castro, R and Meléndez, M, 2016. Gravity flow full-scale tests at Esmeralda Mine’s Block-2, El Teniente, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 349–358 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

I would take this, opportunity of thanking you for the high honour you have conferred on me in electing me to the responsible position of President. You may rest assured I will use my best endeavours to promote the interests of the Institute in every way that lies in my power. In reviewing the work of the past year, it is a matter for congratulation to find the Institute in a position at once so healthy and robust, and that notwithstanding the acute depression which has prevailed in the mining industry.Owing to deaths or departures from the colony, the names of six members have disappeared from the roll of membership, but you will be pleaed to learn that several new members have been elected, the register now, showing 56 Members, 25Associates and 2 Students. A complete record of the papers read and the discussions that took place will be found embodied in the splendid volume of Transactions which has just been issued, and which I am sure will be welcomed by mining engineers in all parts of the world.

Jan 1, 1901

Python Underground Processing Plant Critical Design The use of continuous gravity recovery in combination with a controlled breakage fine crushing and screening system followed by flash flotation has been incorporated into the Python processing plant. This provides miners with a flexible, robust, low cost, low energy pre-concentration process for the recovery of gold and/or heavy minerals. The Python plant incorporates fine crushing utilizing either High Pressure Grinding Rolls or Vertical Shaft Impactors in combination with the InLine Pressure Jig and Flash Flotation to continuously liberate and recover the valuable minerals. The use of these technologies has enabled a narrow, transportable pre-concentration plant to be produced which can easily be installed and operated in underground drifts and tunnels.

Sep 13, 2010

The drill steel' sharpening shop, which stands adjacent to the Chaffers shaft, is built to the dimensions of 110 ft. 9 in. by 58 ft. wide, and is air conditioned in order to maintain reasonable working conditions during the summer months.Figure 1 is a plan of the shop, showing the disposition of the machines and equipment.LIST OF STEEL SHOP EQUIPMENTAir Conditioning Plant comprising:-1 Spray and Eliminator Type Air Cooler, 6' ft. x 7 ft. x 6 ft. with 80 fine sprays.1 No. 36 Keith type ER. Ball Bearing upcast multivane centrifugal fan.20,000 cfm. a in. WG. at 450 r.p.m.Fan motor, A.G.E. S.C. 10 h.p. 1,160 r.p.m.1 Water Pump. 2?!-3-in. Thompson Class G. Single Stage Centrifugal Pump.1 Pump Motor, A.G.E. S.C. 70 h.p. 1,160 r.p.m.Drill Steel Sharpening Equipment:-2 Holman Sharpening Machines, No. 11.1 Ingersoll Rand Sharpening Machine, No. 54.5 Ingersoll Rand Sharpening Machines, No. 50.2 Holman Hot Millers, Type DM. Double Spindle Machines.2 Morgan Hot Millers, Type 1.6 Reamers consisting of motors with Ingersoll Rand Chuck fitted to the shaft and carrying a reamer of i-in. square Ultra Capital Steel Motors, A.G.E. S.C. 1 h.p. 1,160 r.p.m.4 Double-sided Drill Sharpening Furnaces, oil fired with L.P. "Major" 2-in. non-rotary whirl type burners.Combustion Chamber, 2 ft. 4 in. x 6 in. x 12 in. Oil consumption, 3·3 to 3·8 gallons per hour.Furnace Lining, Standard Kyanite.Firebricks, 9 in. x 3 in. x 4 in.2 Moving Frame type double-sided tip hardening furnaces, oil fired using High Pressure Air reduced to 3 lb. per square inch.Combustion Chamber, 3 ft. 5 in. x 5 in. x 16 in.Burners, "Major" L.P. 2-in. non-rotary whirl type.Oil consumption, 3·3 to 3'8 gallons per hour.Furnace lining-bottom and sides, 60 only 9 in. x 3 in. x 4 in. Kyanite bricks.

Jan 1, 1941

By A Watson

We tend to overestimate the volume of water used to process ore and the evaporation from tailings and heap leach stockpiles. During mine operation, a significant portion of the water collected from onsite water management systems is consumed and recycled by ore processing and lesser portion discharged to the environment. When mining and processing cease, however, the mine site water balance is altered and the real effort and cost associated with managing and disposing of excess mine-influenced water becomes evident. As these flows can no longer be recycled and may not be suitable for discharge to the environment, the cost of dealing with them can comprise a significant portion of the post-mining liability. The problem of dealing with large volumes of mine affected water has the potential to become worse in the future due to the established trend of lower grades which require more water per unit of mineral processing. As a result, future mines may be expected to have greater water needs and problems than we experience today.This paper discusses various aspects about how water usage changes when a mine transitions from operation to closure based on observations and numerical simulations of made with site-wide water balance models. The intention is to provide general considerations for mine operations in planning for end of mine life and post-mining care and maintenance.

Jan 1, 2009

By L Forrester

The tube bundle system is an integral part of an underground coalmine’s gas monitoring system. The maintenance of these systems is vital to ensure the quality of the data produced. Integrity testing of the tube bundle lines is required monthly, as specified in Standards Australia AS/NZ 2290.3 (1990). The various forms of integrity testing are reviewed, including pressure testing and introduction of a known gas. This paper provides a recommended and standardised methodology for those techniques where none currently exists. A strengths, weaknesses, opportunities, threats (SWOT) analysis is performed. The parameters considered for the SWOT analysis include resourcing required by the mines, time for the testing to be performed, and quality of the results produced. The suitability of such integrity testing protocols to be used in a mine emergency situation is also evaluated.CITATION:Forrester, L, 2017. Tube bundle integrity testing methodologies, in Proceedings Australian Mine Vent Conference 2017, pp 129–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By A B. Christie, F P. Bierlein

Lode gold deposits of the Western and Eastern provinces, South Island, New Zealand , formed as a part of the Cordilleran-style tectonism during Tasman/Tahua and Rangitata orogenesis along the Paleozoic-middle Mesozoic southern Gondwanan margin. These deposits, hosted by lower grade greenschist facies sedimentary rock sequences of the Buller, Takaka, Torlesse, and Caples terranes, universally show geological features that are consistent with the orogenic gold deposit model, and genetic features are generally suggestive of a metamorphic origin, with the possible exception of a magmatic fluid source for the mineralisation at Sams Creek. However, ore fluid chemistry in Mesozoic deposits of the Eastern province, particularly the low concentration of non-aqueous volatiles and the very dilute nature of the fluids, is uncharacteristic of most orogenic gold deposits; this must be explained by either a unique fluid source or fluid type, which we believe unlikely, or an unrecognised significance of relatively rare gas-rich fluid inclusions in the deposits. Absolute age data for gold deposits in both provinces remain equivocal, thus hindering definition of the exact temporal relationship between ore formation and terrane accretion, regional metamorphism, and magmatic arc emplacement. Mercury and antimony occurrences in subgreenschist grade parts of the Haast Schist may target the upper levels of unrecognised orogenic gold deposits. If low-grade, high-tonnage intrusion-related gold systems occur on the South Island, then they are most likely to be discovered in association with the small molybdenite-, scheelite-, or cassiterite-bearing quartz stockworks spatially related to the Karamea and Median batholiths.

Jan 1, 2005