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By N A. Sikwa, L M. van Niekerk, G N. Ndlovu

In June 2012, Lucara Diamond Corporation officially commissioned its Karowe Diamond Mine in Letlhakane, Botswana. The processing plant circuit incorporates variable speed autogeneous milling, a first for African diamond processing - only previously practiced in Russia. The paper discusses the basis for the selection of milling against the more traditional circuits incorporating crushing and scrubbing. It covers early commissioning challenges of operating a mill in an æalien environmentÆ with no immediate reference plant to look up to for bench-marking.The paper describes how these challenges were overcome and learnings quickly incorporated into the mill operating philosophy for maximum diamond liberation and minimum product damage. The plant was commissioned in three months and by August 2012 the production ramp up had reached name-plate capacity. The feed to the mill has varied from highly weathered material to extremely hard kimberlite and the operating philosophy had to be optimised for the full range of ore types. While more work is required to stretch the mill operating envelope coupled with other circuit additions to improve liberation of fine diamonds at minimum capital expenditure, the mill has, to date, performed to its billing.CITATION:van Niekerk, L M, Ndlovu, G N and Sikwa, N A, 2013. Commissioning and operating an autogeneous mill at Karowe Diamond Mine, in Proceedings MetPlant 2013 , pp 215-228 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By I Swane, R Rait, A Robertson

Geochemical assessment of mine waste materials prior to commencement of a proposed mining operation is a fundamental component of mine feasibility studies and the regulatory approvals process. Static and kinetic geochemical test methodologies are widely used to predict the geochemical nature of mine waste materials and to develop strategies for managing potentially æhostileÆ materials. These data can also be integrated with data from other fundamental studies such as hydrogeology to predict specific environmental outcomes and potential impacts at mine closure and post-closure.A case study is presented for a proposed open pit gold mine in Mongolia, which illustrates how geochemical, hydrogeological and groundwater quality data can be used as part of a geochemical modelling process to predict the final pit lake water quality over time. A series of static and kinetic test geochemical test programs were completed and acquired data integrated with hydrogeological and groundwater quality data provided by the proponent. A widely used geochemical modelling program (PHREEQC) was used to develop the geochemical model and predict water chemistry in the pit void after mine closure. Sensitivity analyses were completed to explore the effects on the model output of groundwater to leachate water ratio, pit wall rock type and climate.Modelling has indicated that pit void water should be pH circum-neutral at mine closure and should remain within Mongolian and World Bank water quality guideline limits under the modelled simulation most likely to occur in the field. Final void water salinity is expected to increase eight fold over 14 years after end of mine life due to a continuous flux of salts (particularly sulfate salts) into the pit lake whilst the pit lake volume will remain relatively constant due to evaporation and a slow recharge rate. Dissolved metal and sulfate salt concentrations in pit water are also predicted to increase over time and could be moderately elevated compared to applied water quality guideline values. Some of the metal concentrations, however, may be lower as these would be expected to precipitate at circum-neutral pH and greater. Recommended additional assessment work on the project when mining commences includes determining the magnitude of adsorption and co-precipitation of metals occurring in the pit void water/sludge system.CITATION:Robertson, A, Rait, R and Swane, I, 2013. Geochemical assessment of mine waste materials and prediction of final pit lake water quality at a proposed gold mine in Mongolia, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 165-170 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By D Brett

"Mine waste storages including tailings dams and waste rock dumps represent arguably the biggest risk on a mine site from both physical and geochemical viewpoints, related firstly to structural stability and the consequences of failure and secondly from potential on-going seepage or run-off of acid and metalliferous drainage (AMD). The risks are most likely to increase during operations and continue through the closure and post-closure phases, with the waste storages likely to be the most difficult features to resolve in the mine closure process. Contaminated water quality from tailings dams and waste rock dumps can require treatment "in perpetuity" at a cost of hundreds of millions of dollars. The problem is increasing with ever larger mine operations and waste generation volumes. This paper identifies leading practice methodologies in planning and operating mines and process plants to minimise the risks from tailings storages and how this might also affect waste rock management and even the design of mine excavations. These methodologies require a "big-picture" approach to develop an understanding of the overall issues and identify synergies between the different operational areas on a mine site that can reduce overall risk. With a conservative approach and realistic allowance for future costs it is possible to facilitate decisions at the mine planning stage that can reduce risk and save cost over the long term. This is in contrast to the common approach where each operational area is looking to minimise its own costs with a short-term view. Incorrect mine methodologies can be developed by allowing net present value (NPV) accounting methods to trivialise future closure issues.Methodologies discussed include: Integrated Waste Management - Significant structural improvements to tailings dams can be achieved if the structures can be incorporated into the waste rock dumps. Risk of AMD can also be reduced by utilising the tailings and waste rock effectively. This could go even further to consider the placement of wastes to limit mine void environmental issues; Process Optimisation - Water quality and the nature of potential tailings dam structures can be highly influenced by the geo-chemistry of the tailings. This can be modified by processing, where simple changes such as maintaining separate streams of geo-chemically different tailings rather than recombining them or by initiating further processing to remove problematic minerals such as sulphides; Enhancing Geophysical Properties - The geochemical performance of waste repositories can be greatly influenced by the geophysical properties of the stored materials, particularly the air-water characteristics, which are influenced by particle size, density and permeability. The geotechnical properties can be enhanced by strategic paddock dumping, blending and compaction.These methodologies are demonstrated by case histories.CITATION:Brett, D, 2013. Mine waste risk minimisation by integrated waste management and process optimisation, in Proceedings MetPlant 2013, pp 247-258 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

Effect of Anionic Surfactant on Silica Particle Attachment at the Oil-Water Interface Controlling particle attachment is crucial where powdered solids come into contact with oil and water. Particles are trapped in a deep energy well at the oil-water interface, stabilising emulsions. Here it is shown that adding anionic surfactant causes dramatic changes to the bulk and interfacial structure of silica particle-stabilised oil-in-water emulsions. Exposing particle-stabilised drops to surfactant concentrations above the critical micelle concentration enhances the rate and extent of creaming and flocculation. Mixing particle-stabilised emulsions with surfactant solutions causes drop fragmentation. As the surfactant concentration increases, the average drop size decreases and particles are displaced from the interface during the mixing process.

Sep 13, 2010

By C Rule

In 2003, Anglo Platinum, in a joint development with Xstrata Technology, installed the world’s first 10 000 litre IsaMillTM in a concentrate regrind duty at the Western Limb Tailings Re-treatment Plant. The success of that installation was the enabling event for Anglo Platinum to proceed with a substantial investment in horizontal stirred milling technology. Since 2006 an additional three IsaMillsTM in concentrate regrind duties and a further 18 IsaMillsTM in the more technically challenging coarse grinding mainstream applications, have been commissioned in group Concentrator operations - bringing the total number of IsaMillsTM installed in Anglo Platinum plants to 22.A collaborative approach between Anglo Platinum and Xstrata Technology towards improving milling efficiency and reducing operating costs, through internal mill component wear optimization and operating recipe development, has resulted in further improvements in the overall success of IsaMillsTM in the flow sheets of many Anglo Platinum operations. The addition of IsaMillsTM in the Anglo Platinum flow sheets has improved plant PGM recoveries by as much as 5%.This paper explores the improvements made to the IsaMillsTM flow sheet and mill internal design and shares some of the operating experience with IsaMillsTM technology in Anglo Platinum

Aug 8, 2011

The transition from low stress to high stress conditions is a challenge eventually faced by most mines in Australia that extend to depths greater than (generally) about 1000 m. In areas with strongly adverse 'stress versus depth' gradients, such as some parts of Western Australia, significant stress-related problems have occurred at depths as shallow as 300 m below surface. The actual depth at which the 'transition' occurs is a function of the local pre-mining stress field, the strengths of the various rock types hosting the deposit and the layout and sequencing adopted in the mine. Stress-related damage can result in increased support costs, and delays associated with rehabilitation and disruption to production. In the worst case, where strong seismicity and associated damage occurs in active mining areas, 'exclusion' zones and 're-entry' protocols may be required. These can severely disrupt production. A key aspect of managing the transition is the recognition of the onset of stress-related ground behaviour. Damage mapping can be used to develop understanding of the relationships between mining activities and the local and regional response to them. Carefully documented case histories provide a basis for calibrating numerical models. This paper discusses some of the typical styles of ground behaviour observed in higher stress conditions in underground mines. A simple damage classification scheme is described to assist in 'damage mapping' of mine tunnels. An example of damage mapping is presented to illustrate an approach commonly used for recording stress-related damage.

Nov 25, 2010

By P Klaric

Drive stability is critical in block/panel cave mining. The production levels of these mines are required to remain operational for the entire life-of-mine which can be in excess of 30 years. It is therefore necessary to produce high-quality drives to ensure sustainable mine productivity. In order to improve the quality of drives and pillars, this gold mine instigated a project to optimise their development blasting. The initial aim was to reduce the level of overbreak in development mining, which was averaging approximately 18 per cent. The benefits of controlling overbreak not only included an increase in the integrity of the drives but also a decrease in load and haul and ground support costs. Through focusing on the optimal blasting of the perimeter holes, overbreak was reduced to 4.5 per cent. The project’s focus then moved to drill and charge designs for development faces. In optimising these designs, it was anticipated that improvements in the development mining cycle would be achievable.CITATION:Klaric, P, 2015. Improving drive stability through efficient development blasting design and practices, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 327–332 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By J Samosir, L A. Snyman

Northparkes is located 27 km north of the township of Parkes in central New South Wales, Australia. The operations consist of underground block cave mines and an ore processing plant that produces high-grade copper and gold concentrate. Production is currently sourced from the E48 Lift 1 block cave mine and open cut stockpiles. Mining commenced at Northparkes in 1994 as an open cut operation. Underground block cave mining began in 1997. Northparkes was the first mine in Australia to use the highly efficient block cave mining method, which relies on gravity and natural rock stresses to fragment the ore.An issue affecting production in 2011 was the stability of the E48 mine. A small portion of the drives on the extraction level began to deteriorate as the ground support system failed. The problem was temporarily fixed by stopping production in three extraction drives and tight filling selected areas within these drives (and drawpoints) with low-strength concrete. This action provided immediate support and stability whilst allowing time to investigate potential ground support remedies. From these investigations it was decided to use resin injection technology and additional ground support to stabilise the rock in the aforementioned extraction drives as the concrete plug was excavated in a controlled advance and sequence. This made the area safe and ensured the ongoing safe operation of the E48 mine. The redevelopment of one of these drives began late in 2011, with the remainder being progressively redeveloped over the next two years in order to maintain the extraction level stability.This paper looks at the strategies employed to safely re-open previously converged drawpoints and associated extraction drives that were subject to high abutment loading that was possibly associated with premature cave breakthrough.CITATION:Samosir, J and Snyman, L A, 2014. Redevelopment at Northparkes following significant drive closure, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 87–92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By G J. Harbort, V Lawson, L Reemeyer

The Jameson Cell is a high intensity flotation device, which utilises induced air from the atmosphere. It was developed jointly by Mount Isa Mines and Professor Graeme Jameson of the University of Newcastle in the 1980s. It is proven to generate fine bubbles, in the order of 300 to 500 ¦m, in a high intensity, high shear and compact zone contained in the downcomer. This aerated mixture exits the downcomer into the pulp zone, which is the quiescent mineral and gangue separation zone. A number of Australian base metal flotation circuits feature a reverse flotation stage at the head of the circuit. Testwork and plant operating data has shown that the use of a Jameson Cell in the prefloat cleaner application has further improved prefloat gangue recovery and selectivity. Operation of a Jameson Cell in a carbonaceous/pyrite prefloat cleaner duty at the Mt Isa copper concentrator increased copper recovery and reduced pyrite in the copper concentrate. Testwork at Zinifex Century Zinc Mine showed a decrease in zinc losses by the utilisation of Jameson Cell prefloat cleaner. Appraisal of a Jameson Cell in a scalping role within the Mt Isa Copper Concentrator indicated significant benefits could be achieved.

Jan 1, 2005

By L Thorburn

In 2009, the Queensland Government developed a series of amendments to environmental authorities (EAs) for mines throughout the Fitzroy Basin in response to studies that assessed the cumulative impacts of mine water discharges in the basin. One of the key amendments was the requirement for all mines in the Fitzroy Basin to develop and implement a receiving environment monitoring program (REMP). The intent of the REMPs was to provide baseline information on the condition of the receiving environments of the mines and any impacts resulting from release of mine-affected water. Since this time, the requirement to complete a REMP has been incorporated into new or revised EAs for mines (including metalliferous mines) in other regions, as well as for other industries that discharge to natural watercourses (such as coal seam gas). This paper discusses the approaches that can be used to incorporate biological monitoring and direct toxicity assessments into REMPs. It highlights the importance of collecting biological data using sound experimental design principles to investigate whether releases resulted in environmental harm; and the use of monitoring data, coupled with direct toxicity assessments, for setting more realistic, site-specific trigger values and release limits (compared to the default guidelines such as Australian and New Zealand Environment and Conservation Council (ANZECC), which may not be appropriate to the region). Implementation of a robust REMP can maximise outcomes for both the proponents and the environment.CITATION:Thorburn, L, 2013. Receiving environment monitoring programs - making the most out of biological indicators and direct toxicity assessments for monitoring of aquatic ecosystems, in Proceedings Water in Mining 2013 , pp 143-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By D Carroll

Mining of the zinc, lead and silver deposit at the Broken Hill Southern Operations site has been occurring for over 100 years. As a result of this, a significant amount of high-grade ore is now taken from narrow remnant pillars left between old stopes and zones of previously mined ground. Stopes have been filled with either hydraulic fill (also known as ‘sandfill’), cemented hydraulic fill (cemented sandfill), waste rock backfill or a mixture of these fill types.In the last ten years, there has been considerable success mining through narrow pillars where sandfill is exposed in the development face and/or walls using a ‘shell’ support regime, wherein a layer of bolted mesh is sandwiched between two layers of sprayed fibrecrete (25 mm fibrecrete, then mesh and bolt, followed by a final 50 mm layer of fibrecrete). Shell support is also used in very poor, broken, relaxed ground conditions and in areas filled with cemented fill (sandfill with a minimum four per cent cement content).The next stage of innovation has been to develop a technique for mining through old stope voids filled with uncemented sandfill, known locally as ‘contours’ (old cut-and-fill working), an activity where unconsolidated sandfill can run at the face and from the backs. The challenge is to prevent exposed sandfill in the face and the backs from failing before it can be supported.To achieve this, the Southern Operations mine has implemented a technique in which 6 m long spiling bars are used to strengthen and stabilise the sandfill in front of the face. The hollow steel bars are driven in around the heading perimeter in a closely spaced pattern then pumped full of grout. The bars and the grout stabilise the sandfill in front of the face, preventing it from failing into the drive during excavation and prior to further support being installed.A final support system consisting of shotcrete, mesh, bolts and steel girders is installed as excavation progresses. Both the initial and final support systems are essentially passive support systems designed for a low-stress environment (as the stress originates mostly from the mass of unconsolidated sandfill).This process is slow and labour intensive. Fifteen separate cycles of people/machinery are needed to progress one equivalent heading cut (compared to six for a standard fibrecrete- and bolt pattern-supported rock face heading). This slow pace introduces scheduling challenges, but the process opens up parts of the orebody that were previously uneconomical to mine.CITATION:Carroll, D, 2014. Mining through sandfill using spiling bars, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 95–100 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By Nixon J. C, Reynolds C

Three principal features of the ore at Captain's Flat, New South Wales, tend to complicate concentration of the valuable minerals, these being:1. The ore occurs in three more or less separate bodies which vary in texture and mineral ratios. Mining of constant proportions of the three sections, or adequate blending of the ore, is not fully effective, and consequently the flotation section is subjected to feedof varying texture.2. The mineral association in the heavily pyritic ore is extremely intimate. Composite particles exist even at 20 micron sizeI, and probably finer.3. The copper content of the ore averages_about 0,6%, which is high enough to justify recovery of the chalcopyrite in a separate concentrate. A review of the metallurgical history of the mine shows that this feature has been the cause of the several major changes in flowsheet of the flotation section since the commencement of milling.METALLURGICAL HISTORYThe mine started production in January 1939, at the rate of 250 tons per day of sulphide ore, assaying 0·68% Cu, 6·52% Pb, 10·8% Zn, and about 1 dwt. Au and 2 oz. Ag per ton.

Jan 1, 1952

By I C. Carrasco, V G. Mirada, J F. D Domingo, F S. Leite

This paper investigates ore loss and dilution produced by rock movement in bench blasting. A total of four blasts, in which electronic detonators have been used, were monitored in Cobre Las Cruces Open Pit Mine (FQM Ltd) in Gerena (Sevilla, Spain). Rock motion has been obtained in 137 points of the free face and 6 points inside the block. Multiple liner regression has been applied to predict rock motion and estimate ore dilution as a function of hole coordinates, rock contacts, powder factor/hole, amount of explosive per blasthole, burden, spacing, hole length, stemming length, explosive energy, hole row, subdrilling, blast sequence, stiffness ratio, blasthole distance to free face, rock density and Young’s modulus. The model is statistically significant with a determination coefficient over 0.8. Rock motion measurements in 31 more points have been used to validate the model and to show a reduction in ore dilution.CITATION:Domingo, J F D, Leite, F S, Mirada, V G and Carrasco, I C, 2015. Dilution, ore grade and blast movement calculation model, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 71–78 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By R C. Morris

Two major types of economic secondary iron ores occur in the banded iron formation (BIF)-rich Hamersley Province of the Pilbara, Western Australia:dominant BIF-hosted bedded iron deposits (BID)detrital ore deposits (DID sensu lato), which are mainly hosted in the three province-wide Cenozoic sequences that include coeval non-ore sediments and comprise:a. the major Miocene, fluvial channel iron deposits (CID)b. the lesser Eocene and Pliocene detrital iron deposits (DID sensu stricto).Striking differences exist between the massive CID resources and the much smaller underlying and overlying DID. CID are essentially riverine alluvial ooidal rocks with abundant small fossil wood fragments and variable iron peloids, but with only extremely rare recognisable lithic remnants. The original matrix is typically ramifying layered goethite. Eocene DID are mainly alluvial with minor pisoids, whereas Pliocene–Quaternary DID are dominantly coarse colluvial gravels, both derived from and largely retaining the original textures of BID, hard cap or variably ferruginised surface BIF. The colluvial DID matrix is typically ferroan-aluminous soil, resulting in canga where replaced by goethite, which may be dehydrated to hematite by exposure. The Cenozoic deposits occur in two dominant geomorphological environments: the southern Marra Mamba to Brockman Iron Formation strike valleys containing all three Cenozoic sequences and the much later northern Brockman Iron Formation plateau valleys that include only the Miocene and Pliocene sequences. The Cenozoic detritals formed in different climatic regimes, with an extended dry period forming a prominent province-wide dehydrated carapace on the Eocene DID. The Miocene ‘optimum’ followed with its thick scrub-covered deep regolith that produced the fossil wood-rich CID and was succeeded by the arid cool period of the Oakover limestone/calcrete. A major renewal of exposure and erosion in the Pliocene resulted in the extensive iron gravels of the Pliocene–Quaternary.CITATION:Morris, R C, 2015. The Cenozoic detrital iron deposits of the Hamersley Province of Western Australia – a tribute to Mal Kneeshaw, in Proceedings Iron Ore 2015, pp 319–326 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By R Butler

Contract m1n1ng in New Zealand developed in the coal industry and has become an element in the success of recently opened hard rock gold mines. At Martha Hill, the mining contractor is undertaking a wide range of activities from open pit mining, crushing, conveying, waste embankment construction and drainage.

Jan 1, 1991

By P D. Munro

On the occasion of the 14th Mill Operators’ Conference and marking 40 years since the first one was held in Mount Isa in 1978, it is fitting to review the history of the Conference and its development over that time.The first 10 Conferences were irregularly held at three to four year intervals, with 9 of these in regional centres of Australasia. It is only since 2012 that the Mill Operators’ Conference has become a regular biennial event, alternating with the MetPlant Conference.The number of people attending the Conference has more than doubled to 470 delegates at the 13th one in 2016. It has outgrown its regional beginnings.Papers presented to the previous Conferences have been analysed according to commodity, country of origin, technology and theme plus the affiliation of the authors to discern any trends that may assist in planning the future events.Suggestions are made as to how the AusIMM might wish to arrange its mineral processing/metallurgical conferences.Recent changes to the structure of the Conference providing a more meaningful experience for the delegates and increasing their interaction and involvement should be vigorously pursued.CITATION:Munro, P D, 2018. Mill Operators’ conferences – a 40-year retrospective and a vision for the future, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 5–14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By R Coleman

The flotation mechanism plays a key role in the flotation process. It is used to provide the contact between solid particles and bubbles and also the energy for these particles and bubbles to attach. The mechanism must therefore provide sufficient mixing to keep the solids in suspension so that they can be transported into the froth and recovered to the concentrate. The design of the mechanism is critical and over the past decade Outotec has developed and optimised a new mechanism design to improve metallurgical and energy performance. The FloatForce® mechanism consists of a rotor and stator arrangement and has been specifically designed to provide sustained mixing at higher air flows and lower power inputs.Over 500 FloatForce® mechanisms have been installed in existing and new operations. This paper outlines the technological aspects of the FloatForce® mechanism and provides metallurgical, operational and energy performance results from a number of flotation circuits in which these have been installed.

Aug 8, 2011

By J Herrmann, J Richards, B Hutchison

An extensive trial of laser-based survey and monitoring systems at Hillgrove Resources Kanmantoo Copper Mine in the Adelaide Hills, South Australia, has proved the capabilities of the system in monitoring rock movements on open pit walls. Initially, the trial involved deploying a Maptek I-Site 8820 laser scanner and the proof-of-concept Maptek Sentry software in the Nugent Pit to monitor ductile rock movements located up to 260 m away. The system was proven to be capable of monitoring various rock movements from 1.5 tonne rockfalls up to a 40 m high toppling wall failure. Data collected from smaller rockfalls was used to help build a database for Hillgrove’s rockfall management program. As part of the trial, the laser scanner was deployed to monitor a ramp movement event, as well as the toppling failure, adjacent to an IBIS slope stability radar. Both devices monitored the slump and the slowly developing toppling movements, with similar results. Although the radar was used as the successful ‘critical alarm’ device for the toppling failure, post-failure analysis showed the laser-based system to be capable of performing a similar role in the ductile rock regime; albeit over much shorter distances than the radar capability. A second laser scanner was deployed to monitor Kanmantoo’s Emily Pit in early December 2014, where it successfully provided critical alarm warnings for a block topple event. Sentry software, which takes advantage of Maptek I-Site 3D spatial imaging technology, was first released in November 2014 to meet industry demand for a cost effective, flexible system to detect movement. Sentry has now been re-launched as a fully transportable monitoring system. Deployed in a custom trailer, the system offers a power and communications module, cellular and Wi-Fi networking and a stable bollard for the I-Site laser scanner and Sentry software. This paper will present rock wall movement data from the Sentry trial and a subsequent two years of monitoring of the open pit walls at the Kanmantoo Copper Mine, at distances out to 750m. In addition, examples of remote geological mapping and small rockfall detection, using the laser scans, will be described. The Sentry system has proven to be beneficial for the continual improvement of slope monitoring and risk management at hard rock mines. CITATION:Hutchison, B, Richards, J, Richards, J and Herrmann, J, 2018. Mine rockfall and rock wall failures – proven digital laser-based approach for monitoring slopes at the Kanmantoo Copper Mine, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 463–472 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

I congratulate The Australasian Institute of Mining and Metallurgy on its decision to hold its Annual Conference here in Western Australia. Western Australia, with its abundant mineral and energy resources, plays a key role in the Australian mining industry... and Western Australia will continue to figure prominently in this vital industry for many years to come. The success of our gold, iron ore, bauxite, mineral sands and other primary industries has enabled Western Australia to contribute significantly to Australia's export revenue and, therefore, to the nation's economic strength. The State's mineral wealth has also provided the impetus for a recent surge in mining related activity, including a dramatic increase in downstream processing of our raw materials. Billions of dollars worth of new project investment is either committed or awaiting final approval - and most of this new investment is a direct result of a healthy and vibrant mining industry. The North West Shelf Project - which has been providing natural gas for homes and industry in Western Australia since 1984 - has also played a key role in stimulating industrial development. The availability of abundant, competitively-priced gas from the North West Shelf has - along with the availability of other raw materials - made Western Australia a more attractive proposition for industrial investment. The company I represent, Woodside Offshore Petroleum, is operator of the North West Shelf Project on behalf of the Project's six Joint Venture Participants - Woodside Petroleum Ltd, BHP Petroleum (North West Shelf) Pty Ltd, BP Developments Australia Ltd, Chevron Asiatic Limited, Japan Australia LNG (MIMI) Pty Ltd and Shell Development (Australia) Proprietary Limited. The theme for this Annual Conference: "Excellence - the key to the continued success of the Australasian mining industry" is appropriate to the North West Shelf Project. The pursuit of excellence has been a hallmark of the Project. The Joint Venture Participants have been conscious of the need for stringent quality control at all stages of development. Procurement and purchasing policies, for instance, have demanded strict adherence by contractors and suppliers to the highest standards and specifications.

Jan 1, 1989

By P A. Grossman, J H. Rubinstein, M Brazil

The installation of truck turntables at above-ground crushers has the potential to yield gains in efficiency and productivity by eliminating the need for the trucks to turn around and reverse up to the crusher to dump their loads. The benefits include savings in time, fuel consumption and tyre wear. In addition, having a smaller area near the crushers dedicated to manoeuvring the trucks can be a significant benefit at some sites. Safety is also enhanced using turntables.This paper describes a project with the Australian Turntable Company to develop software that generates near-optimal layouts for the paths taken by the trucks in the vicinity of the crushers when turntables are present or absent. The geometry of the paths is constrained by the turning radius of the trucks and by the boundary of the manoeuvring area. The software quantifies the benefit of installing turntables by generating a design for paths with turntables and comparing it with the layout in current or planned use by the mining company. Through the use of this software tool, a mining company can readily assess the benefits of using turntables at their site.CITATION:Brazil, M, Grossman, P A, Rubinstein, J H and Thomas, D A, 2014. Demonstrating efficiency gains from installing truck turntables at crushers, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 259–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014