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By A F. Cropp, D J. Bradshaw, W R. Goodall

Mineralogy and critically the texture of both the ore and gangue phases are of paramount importance in the flotation recovery of copper from porphyry ores. Mineralogy and texture will define the theoretical grade recovery curve for a feed ore. Actual grade-recovery falling below this may be due to texture and gangue influences, whilst desired grade-recovery above this line will not be possible unless the characteristics of the feed are altered.This review discusses examples of porphyry copper deposits where process mineralogy has been used to characterise these textural and gangue influences on recovery by flotation. More specifically, the influence exerted by grain size, liberation, association and elemental distribution is explored. The implications of these on overall plant philosophy and operation are highlighted, along with the subsequent potential impact on recovery.CITATION:Cropp, A F, Goodall, W R and Bradshaw, D J, 2013. The influence of textural variation and gangue mineralogy on recovery of copper by flotation from porphyry ore - a review, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 279-292 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By T J. Beardsmore, N Wyche, D Flint, T J. Griffin

Western Australia (WA) is currently the world’s largest iron ore producer, and mining of its huge reserves and resources of iron ore has become a critical part of the state’s economy and regional development. Iron ore exports from WA have reached 760 Mt/a, corresponding to shipping more than one Mt per turn-of-the-tide from the state’s ports. The iron ore sector dominates all commodities produced in WA, and in 2016 accounted for 77 per cent of the state’s royalty receipts, 56 per cent of mineral and petroleum exports (by value) and 50 per cent of mining industry employment. Expenditure on exploration for iron ore (including that for resource estimation and conversion to ore reserves) has declined markedly, from its record peak of $1100 M in 2012 to $280 M in 2016, placing it second after gold. Foreign investment has been a key element underpinning development of the iron ore industry from the 1960s until today, and will likely continue to be so into the future.CITATION:Flint, D, Wyche, N, Beardsmore, T J and Griffin, T J, 2017. The importance of iron ore to Western Australia’s economy, in Proceedings Iron Ore 2017, pp 7–12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Kepplinger W

The KR Process is a joint development by VOEST-ALPINE, Austria and its subsidiary company KORF ENGINEERING, Germany. This new technology allows production of hot metal on the basis of non-coking coal. The KR Process is based on the idea of separating the process steps realized in the blast furnace (generation of reduction gas, reduction of iron oxide and melting of the reduced iron) and including coking of coal. These reactions are carried out in two reactors: - the melter gasifier, where non- coking coal is coked and gasified into a high quality reduction gas and hot prereduced iron is melted. - the reduction furnace, where iron oxide is reduced by the reduction gas generated in the melter gasifier and discharged in a hot state. In order to prove the process a pilot plant has been set up in Kehl/ Rhine in 1981 with a nominal capacity of 60.000 tpy.

Jan 1, 1986

Large deposits present computational challenges to todayÆs commercial orebody modelling systems that are based on conventional block models. We describe a system that is specifically engineered to model and visualise large deposits. Central to the system is linear octree encoding of conventional block models and real-time conversion of three-dimensional (3D) meshes to linear octrees. We provide both methodological treatment and practical experience in implementing such a system. A commercial implementation is also presented to demonstrate the validity of the approach.

Sep 26, 2011

By I Gipps

A vision of what the future mine involves all aspects of mining, ie orebody access, ore stoping, material transport, processing and waste material disposal. This paper examines one aspect of the future mine: rock extraction, stoping, automated for remote operation, high productivity and low cost. Concepts for the future require a re-think of the mining process and ROES® re-examines how bulk stoping of ore can be undertaken and how this should be redesigned to accommodate the possibilities that exists with remote control and automated operations.ROES® is a new mining system for underground mines and quarries utilising a shaft located close to or within the stope for the ore breakage process. The system is designed to exclude personnel from contact with production drilling, explosive placement and detonation so all of these tasks are remotely controlled or automated. Survey of the shaft, stope back and broken rock within the stope will occur, following each blast, by remote control or automated techniques. The survey will include excavation geometry, rock fragmentation, geotechnical characterisation and estimation of ore grade. Blastholes will be surveyed before placement of explosives and, with the survey data, the optimal explosive placement and blast timing will be determined with the best available information.ROES® is designed for application in open stoping or sublevel caving in disseminated, geologically defined, thick tabular or narrow vein ore bodies. Technologies developed for ROES® will also have potential applications to caving operations, reducing the risk of frozen ore and poor fragmentation. In a typical sublevel open stope application, ROES® will reduce the stope associated development by half and will allow ore to be brought on-stream sooner and at lower cost. Other savings will flow with the centralisation of mining activities and operational data, reduction in mining fleet, reduction in ventilation requirements, improved occupational safety and reduced mine complexity.

Nov 22, 2011

By K Rau

The overall success of a mining operation is directly impacted by the reliability and availability of mining equipment. Heavy-duty vehicles such as excavators and haul trucks are used for conveying of bulk material and improving such assets’ availability helps reduce costs, increase throughputs and improve safety (Ravande, 2022). If a mining operation’s key performance indicators (KPIs) are tied to operational performance, then overall equipment effectiveness (OEE) is an essential metric to track progress and to identify areas of improvement.

Sep 1, 2024

By J Player, P Evans, G Sweby

Achieving quick underground access after the completion of an open pit mine can be critical to maintaining project value and ensuring regular ore feed to the mill. This paper outlines the design and construction for two portals in an active open pit to commence underground development quickly whilst installing appropriate ground control to maintain long term access in an uncertain setting. Implementation of the portal designs was complicated by the change in underground design from hangingwall access to footwall access late in the life of the open pit due to preferable ground conditions. The portal locations did not have easy access for ground support installation integrated into the pit design due to the timing of the underground design changes. Practical implementation of the ground support systems subsequently became a key part of the project. Intact rock strength, rock mass characteristics, gradational weathering / alteration profile and structural information were modelled against pit displacement monitoring as the basis from which the portals were located and ground support schemes designed. Conditions around one of the portals necessitated numerical modelling to estimate the appropriate level of ground control for long term stability. The design was completed whilst the open pit was actively on-going and the portal areas not entirely exposed. The rock mass assessment and analysis for the two portals indicated different ground support scheme capacities would be required. The expected level of control for one of the portals also necessitated the use of monitoring with extensometers and load cells to ensure the rock mass response and ground support scheme performed as planned. Construction of the portals demonstrates the benefit of a considered design process, a plan which allows practical installation of ground support schemes where access is limited, the benefit of ongoing monitoring to ensure performance remains within design limits and the challenges involved working within an active pit with limited floor space.

Mar 15, 2021

Routine, in-pit geological mapping of highwall at Central Queensland Coal Associates (C.O.C.A.) deep strip mines has proved too slow for the increasingly greater highwall lengths which require mapping. This realiz- ation has encouraged the search for faster mapping methods and after trial of ground photographic methods has resulted in the adoption of interpretive mapping off stereo cover, oblique -- aerial photography. This entails using a Cessna 182 light aircraft flying at its slowest speed, the aerial meth- od finally employed consisting of two Vinten, air reconnaissance cameras mounted in parallel and simultaneously taking both colour and black and white photographs of the mine high- wall. The respective 1:500 scale enlargements produced from the 70mm format films combine to present the sharpest resolution attainable under the field conditions pertaining and such information on weathered material as only colour photography can fully render. Total costs for the aerial photography method are estimated to be about the same as those for conventional in-pit mapping. Whilst total costs are comparable, geo- logist's time for mapping a 10 km. length is reduced to less than half that for in-pit mapping (for Stage 1, fully accurate mapping) and accuracy and detail are greatly improved. A permanent, accurate record of overburden

Jan 1, 1981

By Henderson J

Iron ore samples selected from the Deepdale, Iron Prince and Mt. Newman ore bodies have been pelletised on a pilot scale plant and subsequently reduced under laboratory conditions by hydrogen or carbon monoxide. Pellets approximately 1 cm in diameter have been reduced by hydrogen over the temperature range 5000- 900¦C and the results examined by thermogravimetric, microscopic, electron probe and x-ray techniques. After an initial time delay it was found that up to 95% reduction the rate of reduction could be described by a transport con- trolled porous model, in which the effective diffusivities of hydrogen in theòpr¦duct layer and the reaction zone are filar. Independent measurements of effective diffusivity supported the values obtained from the reduction data. ve 95% reduction the rate decreased markedly due to the formation_of retained wustite or fayalite. Comparison with reduction by carbon monoxide over the temperature range 7500 - 900¦C showed that the rate eduction by carbon monoxide was approximately five times slower than the rate by hydrogen. The rate of reduction was found to be a function of the properties of the pellets, which may account for the ely conflicting results that have been obtained in previous investigation on porous pellets.

Jan 1, 1970

By M Haest, S Sandler, R Botha, H Lang, K Hume

Benchmark practices in the mining industry include the establishment of Quality Programs — Quality Assurance and Quality Control (QAQC) — to monitor the correct execution of sampling protocols and control each stage of the ‘Sample Cycle’: Sample Collection, Preparation (comminution) and Analysis. QAQC reports commonly include statistical-numerical results that quantify performance of QAQC controls (field duplicates, preparation duplicates, blanks, standards etc). Graphics such as scatter plots, QQ plots, histograms and cumulative frequencies are used to represent the results. Statistical values including relative difference, absolute difference, relative variance, averages, T-test, and Zscores are used to quantitatively express the relationship between duplicate pairs ... but is an effective quality program just a statistical exercise? This paper aims to highlight the concept of ‘Quality Management’ (QM) as the precursor of continuous monitoring (ideally in real time) of QAQC results on Exploration, Production, Processing and Port samples, determined by trend analysis performed on a time and/or grades basis. Currently, there is a paradigm in the process of quality assurance that if individual data points fall within a predetermined acceptance limit then they are ‘acceptable’ and therefore suitable for informing operational and investment decisions. However, what is stated with respect to QM is that sometimes results found within the acceptance limits can indeed be internally biased, or show material deviations over a period of time, thereby impacting reconciliation results and/or potentially creating discrepancies with the final buyers. QM refers to the proactive detection of these ‘anomalous tendencies’, the approach and communication with the source of the information, the understanding of the reasons that cause the deficiencies, and the generation of agreed action plans to remediate the situation and ensure the consistency of results, in other words: continuous improvement on proactive manners.

Mar 22, 2022

By R Buerger, D Barrett, P Hodkiewicz

The Emily Ann nickel mine is owned and operated by LionOre Mining International Ltd. The deposit was discovered during 1997 and is blind, concealed beneath 25 m of transported cover and a further 100 m of unmineralised Archaean felsic rocks. Nickel sulfide mineralisation is hosted predominantly in strongly deformed, altered and metamorphosed Archaean komatiitic ultramafic rocks. Subordinate felsic-hosted, remobilised mineralisation is also present. Mining of ore commenced during late-2001. Since the early days of exploration drilling, through feasibility delineation drilling and subsequent mining, a geological model involving thrusting and folding of a komatiitic-hosted nickel sulfide deposit has been an evolving theme. Development of appropriate mine geology procedures, including detailed mapping, significantly increased the confidence of mine-site geology and engineering staff in the geological model and improved operational efficiencies during start-up. This also allowed the engineering and mining team to develop a tolerance for the large fluctuations in daily production grade, with an understanding that budgeted production targets, on a level-by-level basis, were achievable. This paper describes the development of the current interpretation of the deposit and emphasises the importance of a sound understanding of deposit geology. The direct benefits at Emily Ann included improvements in drill targeting, resource estimation and mine planning.

Jan 1, 2003

Location & Permit Status Three major Mesozoic Tertiary basins exist along the continental shelf area of southeastern Australia, known as the Bass Strait area. They are the Gippsland (east of the longitude of Melbourne) Otway (west of Melbourne) and the Bass (underlying central Bass Strait between Victoria and Tasmania). The total area, both onshore and offshore, is approximately 100,000 square miles. In March 1960, the Broken Hill Pty. Co. Ltd. acquired exploration title to the continental shelf areas of the Gippsland, Bass and Otway basins from the States of Victoria and Tasmania. The title to that part of the Otway Basin in South Australian waters was granted in July, 1961. Other exploration permits, being 8 miles wide in Gippsland, held by Woodside :E.) Oil Co. N.L., and 15 miles wide along the southwest coast of Victoria, held by Mobil-BP-Interstate Oil (Frome-Broken Hill Co. Pty. Ltd.), were in existence prior to granting the B.H.P. title. Subsequently, Shell, B.H.P., Esso and Magellan have been granted title to the remaining areas of the continental shelf in the basins under discussion. In three separate agreeme negotiated between 1964 and-1966, Esso obtained farm-in rights to B.H.P.'s Gippsland, Bass and Ott' Permits.

Jan 1, 1970

By N Harries

The management of risks associated with slope instability is an essential process in the safe and economic operation of open cut mines. The æslope stability radarÆ (SSR) has been developed to better manage those risks. The SSR can remotely scan a rock slope to continuously measure any movement of the face. The system can detect and alert users of wall movements with submillimetre precision. The high level of movement precision and broad area coverage of the rock face can allow for a better understanding of the geomechanics of slope deformation, including magnitude of potential failures and additional warning time of impending instability. Additionally, radar waves adequately penetrate through rain, dust and smoke to give reliable measurements, 24 hours a day. SSR systems have been deployed in many mines in Australia, Indonesia, Africa, Chile and the United States. Greater than 100 rock falls and waste dump failures (from several tonnes to millions of tonnes) have been monitored, and on every occasion precursor æwarningÆ movements were recorded by the SSR. This technology enables a radical change in the management of risks in open cut mining. This paper presents recent case studies of how the SSR technology has provided safety and productivity benefits to large open cut metalliferous mines.

Jan 1, 2007

By Oversby B, Wellman P, Wyborn D, McPhie J, MacKenzie D

The Bureau of Mineral Resources (BMR) and the Queensland Mines Department are engaged in integrated regional- and deposit-scale studies in the Burdekin Falls-"Conway" area, about 100km southeast of Charters Towers (Fig. 1). The regional work augments recent mapping in the Mount Coolon area farther south (Hutton et al., in prep.). These studies are aimed at improving understanding of gold mineralisation and its geological setting in the Drurunond Basin and associated rocks. Knowledge of the regional stratigraphic- structural framework and setting of mineralisation has until now been based on investigations dating from the early to mid 1960's (mainly Bowen 1:250 000 Sheet; e.g. Paine et al., 1974; Wyatt et al., 1971), and on regional syntheses (Olgers, 1972; Levingston, 1981). Some recently explored epithermal gold occurrences in the region have been interpreted on the basis of this early work as being hosted by the Late Carboniferous Bulgonunna Volcanics. The objective of our field research was to refine the regional geology, paying particular attention to the Bulgonunna Volcanics. The results summarised here indicate that unnamed Devonian-Carboniferous volcanics (DCv) of the northern Drummond Basin and mid to late Palaeozoic granitoids are much more extensive, and the Bulgonunna Volcanics much less so, than was previously recognised.

Jan 1, 1989

The appearance of the Cornish miner in South Australia was, in the simplest terms, the result of resource development economics. In Cornwall in the middle of the 19th century tin and copper mining was declining, while in the new colony of South Australia copper mining was booming. Experienced hard rock miners in Cornwall there- fore escaped unemployment at home by accepting an assisted passage to South Australia. There, in a colony where they were needed, they made their skills available and received good wages. There are many testimonies which support this simple thesis. Take for example the following extracts from contemporary newspapers in Corn- wall: Persons of small capital will find this an excellent opportunity for emigrating to the young and thriving colony ... The miner will find a rich and unbroken field for his operations. The Colony abounds with minerals... (West Briton, 19 July 1844) Miners make a great deal of money here (South Australia). All of them earn ú2 to ú3 per week and in many cases when they have a portion of the mine on tribute one person has cleared ú100 in a couple of months or so. (Cornwall Royal Gazette, 21 July 1848)

Jan 1, 1987

Experimentation with new methods, materials and machines to improve primary drilling and blasting is a continuing practice in the hard rock quarry operations of the BMI Group. These experiments will continue in the remote hope that one day we may produce a perfect feed for the primary crusher. As this day is still a long way off, the necessity to break oversize boulders will be a problem to be faced for the foreseeable future. To gauge the efficiency of primary blasting from this point of view, BMI monitor the tonnes of material crushed in the primary crusher for each boulder requiring secondary breaking. Over a period of about 10 years, this figure has improved from 30 tonnes througi the primary crusher per boulder, to 100 tonnes per boulder at our largest operation, which produces in excess of 2 million tonnes per year. Evan with this improvement, 25,000 boulders require secondary breaking each year This paper does not provide the solution to this problem, as like primary blasting, it will have to be constantly reviewed as new products and techniques become available. The paper sets out all of the methods tested or considered for test by BMI and our nnnn1iicinnq nn Chair PffPr.tivPness . Economic

Jan 1, 1978

Elimination of zinc by the reduction of iron works dusts is examined. The process consists of blending, filtration, drying, balling, preheating and reduction in the rotary kiln. Dust slurries and dry dusts are mixed and stored in slurry basins and the blended slurry is filtered. In the balling process it is important to make green pellets which will withstand Thermal shock in the preheater and rotary kiln. Preheating to about 2000C is preferred to ensure effective use of coke fines in the blast furnace dust. The coke retained in the pellets accelerates the reduction rate. However, at the initial stage of the reduction the pellets become weakened and have to be heated slowly to prevent ring formation. In order to ensure zinc vaporization, pellets should be heated to a temperature of 1100-11500C in the kiln with injection of l ignite fines from the discharge end. Pellets having a degree of metallization of more than 90% and containing less than 0. 1% zinc have been obtained using a test kiln. The final pellet product is intended for use as blast furnace feed. A new plant with a capacity of 20, 000 tonne of dust per month is now under construct- ion and will be in operation next year.

Jan 1, 1974

The Australian Mining Industry Council (A.M.I.C.) was established in 1967 as a body to co-ordinate the interests of the mining industry on a nation-wide basis. Its member- ship now embraces the great majority of mining groups in Australia. One of A.M.I.C.'s major continuing functions since its formation has been to work with Governments towards the enactment of more effective and efficient mining legislation. Yet, over the period, the,overall position, if anything has deteriorated. The main reason for this was that because of the rapid succession of what appeared to be quite separate problems during the period there was never sufficient time for Govern- ments to take stock of a situation before it would be changed by a new set of circumstances. By early 1973, the Council was certain that most of the various questions raised were really part of the one overall land use problem and its work in this area thus took a new emphasis from that time. In discussing the Council's involvement with Australian mining legislation over the last six years, the paper helps to clarify the present situation. It then explains a land management system which the Council believes could pro- vide the basis for the type of enlighened

Jan 1, 1974

By D Alexander

For nearly 100 years, the flotation plant metallurgist has often wondered what is happening æbeneath the frothÆ. To assist in unravelling this mystery, new technology has been developed as part of the Australian Mineral Industries Research Association (AMIRA) P9 project, to measure gas dispersion characteristics (such as gas hold-up, superficial gas velocity and bubble size) in industrial flotation cells. These measurements have been conducted in a large number of cells of different types and sizes by researchers from the Julius Kruttschnitt Mineral Research Centre (JKMRC) and JKTech. A large database has been developed and the contents of this database are described in this paper. Typical cell characterisation measurements show a wide spread in values, even in the same cell types and sizes performing similar duties. In conventional flotation cells, the typical gas hold-up values range from 3 - 20 per cent, bubble sizes range between 1 and 2 mm, and superficial gas velocity ranges from 1 to 2.5 cm/s. The ranges of cell characterisation measurements given in this paper will enable plant personnel to compare their operation to other similar types of operations from around Australia and the rest of the world, giving opportunities for further improvement to flotation plant operations.

Jan 1, 2005

By Hopkins G. M F

Intensive exploration of the Archaean ultra mafic sequence bordering the Kambalda dome has resulted in the discovery of at least ten dis- tinct areas of nickel sulphide mineralisation subsequent to the initial drill intersection in January, 1966. Sulphide ore reserves to June 30, 1972 were 19.36 million tonnes at 3.3% nickel after mining of 3.0 million tonnes at 3:7%,nickel since production commenced in March, 1967. About 75% of contained nickel metal reserves occur in sulphide concentrations located at the base of the-ultramafic sequence, in contact with underlying meta-tholeiitic basalt. The remaining reserve occurs in concentrations of sulphides within the ultramafic sequence, usually within 100 metres of the underlying contact and typically in proximity to contact mineralisation. These hanging wall orebodies are smaller, contain significantly lower con- centrations of sulphide, and generally exhibit higher Ni:S ratios than underlying contact ore- bodies. The majority of contact sulphides concentr- ations form narrow, elongate, north north-west trending bodies, closely coincident with fault bounded depressions in the contact. Detailed study of the Lunnon Shoot ore environment in- dicates that it was a locus of crustal failure during, and subsequent to, emplacement of ultra- mafic rocks. Resultant structures parallel and

Jan 1, 1973