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By R Cox, S Pandey

The coal seam gas (CSG) industry is expanding rapidly in the Surat and Bowen basins. CSG production involves pumping water from the coal seams to release the gas adsorbed to coal particles. The reduction in water pressure in the coal seams will cause some reductions in water pressure in overlying and underlying aquifers because there will always be some interconnectivity between the formations. The Surat Basin is a sub-basin of the Great Artesian Basin, which contains aquifers of high economic, environmental and cultural value. The Condamine Alluvium is also an important water resource, which overlies parts of the eastern margin of the Surat Basin.Under the Queensland (Qld) regulatory framework, an area of intensive CSG development involving multiple CSG operators can be declared to be a cumulative management area. For such areas the Office of Groundwater Impact Assessment develops assessments of future impacts on aquifer water pressures and develops and manages arrangements. The results are published in underground water impact reports.The Surat underground water impact report (QWC, 2012) was approved in December 2012. This paper summarises the place of the report in the Queensland regulatory framework, the content of the report and progress in its implementation.CITATION:Cox, R and Pandey, S, 2013. Managing groundwater impacts in the Surat Basin, in Proceedings Water in Mining 2013 , pp 169-174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By L N. Loganathan

Risk exposure in tunnel projects is extremely high due to various factors such as variability of subsurface conditions, selection of inappropriate design and tunnelling methods, improper risk assessment on adjacent surface and subsurface structures and utilities, and inadequate contractual practices. The risks in tunnelling must be borne by the contractor, designer and the owner of a tunnelling project. There have been a number of improvements in the last ten to 15 years in the manner in which tunnel projects are developed and implemented in terms of their design, construction, financing and operations. One significant improvement has been the manner in which underground conditions and their risks are being managed. Owners are less willing to transfer the full responsibility to the contractor for managing the underground conditions, although this is a familiar manner in which underground major urban projects have been previously contracted and managed. The owners of tunnel projects in Singapore have advanced the risk management process for their projects through geotechnical interpretative baseline reports (GIBRs), geotechnical data reports (GDRs) and project specifications (PSs). This paper discusses industry practice and its development as well as the application during the preparation and use in Singapore on the Deep Tunnel Sewerage System (DTSS) and the Marina Coastal Expressway (MCE) project in Singapore. The DTSS trunk sewer is 48 km and ranges from 3.3 m to 6 m finished diameter up to 50 m below the ground. The underground conditions ranged from Old Alluvium, strengths of about 1 MPa to competent Bukit Tima granite, with strengths of over 230 MPa. The total route length of the MCE is about 5 km. About 3.6 km will be constructed underground, consisting of dual five-lane carriageways. The underground construction will be cut-and-cover, and 2.6 km will be constructed about 13 m underground, and 1 km of tunnel will range from 13 m to 24 m as the tunnel passes under a 420 m wide reach of Marina Bay, whose crossing will be constructed as a two-phase cofferdam.

Jan 1, 2008

By C Simpson, J M. F Clout, G Plummer

Detrital iron deposits (‘DID’) in the Hamersley Province of Western Australia have been successfully mined and processed as small quantities of saleable standalone or blended lump and fine ore products over many decades. Despite their past, present, and potential future exploitation, they have received far less geological attention than the economically more significant higher grade bedded iron deposits (BID) or channel iron deposits (CID). DID are composed of Pliocene to Quaternary unconsolidated colluvial/alluvial hematite gravels with minor sand, silt, and ferruginous clay, as well as minor iron rich hematite clast conglomerates. DID mineralisation at Solomon has been subdivided into six distinct stratigraphic units, DID-5 (lowermost) to DID-0 (uppermost) based on differences in clast and matrix textures and mineralogy, degree of consolidation/lithification, particle size distribution and replacement textures. The most significant accumulations of DID-1 to DID-5 are in tributary valleys that have been cut through the Joffre Member of the Brockman Iron Formation on either side of the main Kings-Queens valley which contains the CID. DID-5 and DID-4 are ferruginous conglomerate, referred to as canga, with four subtypes recognised. DID-4 is composed of BID hematite clasts cemented by hematite or goethite. DID-5 is characterised by partial to complete replacement of BID hematite clasts and matrix by the yellow ochreous and brown to black vitreous forms of goethite. DID-3 to DID-0 are unconsolidated hematite detritals composed of largely (>80 weight per cent) fine to coarse gravel, minor sand and little silt or clay. The gravel clasts are largely composed of hematite and hydrohematite that replace BID, micro-nanoplaty hematite-martite-ochreous goethite (m-nplH-M-oG) BID, reworked canga, hematite pisoids, siliceous hematite BID (micro-nanoplaty hematite-martite-quartz, m-nplH-M-quartz), chert (~10–20 per cent) and minor (<5 per cent) Banded Iron Formation (BIF). Hematite abundance decreases from DID-3 to DID-0 whilst siliceous hematite BID is highest in abundance in DID-0 and lowest in DID-3. A key finding of the study is that >90 per cent of mineralised detrital clasts are derived from hypogene altered BID micro-nanoplaty hematite-martite with subsequent later supergene ochreous goethite mineralisation hosted by the Joffre Member. The DID genesis model entails interpreted Palaeoproterozoic siliceous hematite hypogene microplaty BID mineralisation of the Joffre Member undergoing Cenozoic supergene leaching of quartz and replacement by ochreous goethite to form low phosphorous BID micro-nanoplaty hematite-martite-ochreous goethite clasts. BID martitenanoplaty hematite-martite-ochreous goethite clasts and detritus eroded from hill slopes were deposited in the valleys as an initial single DID-5-DID-4 unit over a weathered pre-CID basal conglomerate. DID-5 and DID-4 underwent goethite cementation of the matrix followed by replacement by hydrohematite, hematite, and maghemite. DID-3 formed during subsequent periods of erosion of largely DID-4 hematite clasts and pisoids. Groundwater flow-through hematite canga resulted in partial to complete hydration replacement of DID-4 hematite clasts and matrix by ochreous and vitreous goethite to form DID-5. Deposition of DID-2 to DID-0 was via reworking and deposition of DID-5 to DID-4 canga and DID-3 as clasts and pisoids/ooids, as well as siliceous hematite and BIF sourced from the Joffre Member in the hill slopes.

Nov 8, 2021

Ilmenite (FeTiO3) is the primary global source of titaniumdioxide which is commonly used as a whitening agent in papermanufacture and a pigment in paint manufacture. In WesternAustralia ilmenite is processed by the Becher process (Becher,1963, Becher et al, 1965) where ilmenite particles are feddirectly into the furnace with coal and heated to form acomposite of elemental iron and TiO2. The mechanism of thecarbothermic reduction of ilmenite has been extensively studied(Grey, Jones and Reid, 1973; Jones, 1973; Grey and Reid, 1974;El-Tawil, Morse and Francis, 1993) and is reasonably wellaccepted.

Jan 1, 1997

Xstrata CopperÆs Mount Isa Copper Operations is located in mineral rich north-west Queensland and is one of the largest sources of copper in the world. This world-class underground operation is planned to produce over 6.6 million tonnes of copper ore in 2007 from the X41 and Enterprise Mines. With an underground mining history of over 50 years and underground reserves of over 83 million tonnes at 2.6 per cent copper, mine planning for the future becomes an exciting challenge for the technical team due to the older nature of certain areas. The 1100 Orebody of the X41 mine was one of the first places that copper mining occurred, with its discovery in 1953 - 1954 and mining commencing in the 1960s. Sublevel open stoping mining methods have been employed since that time as the means of extraction, using a primary-secondary sequence to maximise stope turnaround time. Large Transverse Pillars within the 1100 orebody were not mined out in order to provide access for ventilation, power, orepasses and other services. The Panel Pillar, 4180XC and 4010XC pillars are three such Transverse Pillars in the 1100 orebody that will be mined as a final retreat. This paper discusses the technical challenges and issues associated with the extraction of Q390 stope, one of the stopes located in the Panel Pillar, and the design solutions to overcome these issues. Managing the exposure of backfilled stopes of variable fill strength, ensuring the stability of the crown, stope walls and drawpoints, managing vertical openings, re-establishing service networks, and stope filling are the critical issues given consideration for the final design of Q390 stope and other such stopes within a Transverse Pillar. Communication and coordination between the different departments in the mine are essential for the necessary work to be completed in a timely manner to bring pillar stopes into production.

Jan 1, 2007

The æMountain Camp reefÆ at Alford&apos;s mine, Wakamarina,Marlborough, had no recorded gold production although assays of 5 - 26 g/t were reported, but it did produce c. l000 kg of scheelite. The lode consists of a lower massive quartz layer, and upper, cm-banded, ribboned quartz layers, and has a very low sulphide content. Within the massive layer, relict early fine-grained mosaic quartz with idioblastic scheelite is surrounded by recrystallised granoblastic coarse-grained quartz with calcite and plagioclase, in which an original ribbon banding texture is mimiced by strings of tiny inclusions. In both the banded and massive layers, rounded quartz grains, created by cataclastic milling of grain margins and along syn-vein fractures, have been partially annealed within later quartz overgrowths. Late fibrous quartz and calcite fill brittle cross fractures. &nbsp; Deformation events D1 and D2 are associated with mid-late Jurassic metamorphism of the Pelorus Group, D2 producing the main regional schistosity (S2, and the earliest scheelite. D3 is an extensional mylonitic shear event that formed the dominant schistosity in Alford&apos;s mine (S3). The quartz lode was emplaced within the mylonite by a series of individual dilation pulses (D4). The D5 event caused crenulation of the S3 mylonite, kink banding and chevron folding of the S2 schist and S3 mylonite, and reverse faulting, rodding and cross-fracturing with late fibrous quartz-calcite veining of the D4 quartz lode. &nbsp; Fluid influxes during successive dilations of D4 fractures progressively caused recrystallisation of earlier quartz bands on the footwall, annealing and recrystallisation of quartz along milled crystal margins and fractures, and deposition of minor sulphides. There was thus a dynamic interplay between fault dilation, lode fracture, fluid influx, lode band deposition, and lode recrystallisation. Illite-Kfeldspar al ¦ 2 Ma (K/Ar), c.30 Ma after metamorphism.

Jan 1, 1996

By N Guresin, A Cooper, L Lorenzen, H Muller, S C. Dominy

Sampling and metallurgical test work during various phases of engineering?studies?is of?paramount importance for a robust processing plant design. When developing a process flow sheet, risks in achieving desirable financial outcomes are minimised by ensuring appropriate sampling and adequate metallurgical test work supports the engineering and cost estimation at each phase of project development.The quality and type of samples used for metallurgical test work are just as important as the metallurgical test work itself. The key characteristic required of any sample is that it represents some defined portion of a mineral deposit. Representivity should take into account the spatial orientation, lithology, alteration, degree of oxidation, mineralogy and competency of the ore such as hardness and abrasiveness. Statistically representative sampling procedures and an appropriate metallurgical test work program should be designed to bring metallurgical understanding up to feasibility study standard and to give a basis for process plant design.Snowden has observed that the quality of sampling and quantity of metallurgical test work carried out during the various phases of engineering studies are often insufficient to truly support a robust plant design. Some designs are often the result of the plant design based on benchmarks of apparently similar orebodies or buoyant metal prices supporting cash flows until rectifications can be implemented.The paper will discuss important aspects of sampling and test work required for engineering studies in designing process plants based on industrial case studies.CITATION:Guresin, N, Lorenzen, L, Dominy, S C, Muller, H and Cooper, A, 2012. Importance of effective sampling and test work protocols for process plant design, in Proceedings Sampling 2012 , pp 95-108 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By Rowe J

The case study is based on the largest ore deposit at Mt. Lyell; the Prince Lyell deposit, comprising a regular lensoid mass of dissemina- ted and vein pyrite-chalcopyrite mineralisation. Reserve estimation employs conventional techniques, based on diamond drill hole and relevant development sampling data. Probable ore reserves are estimated using the contouring (isoline) method an longitudinal projections for ore thickness and accumulation (m %Cu) at a &apos;0.8% Cu&apos; cutoff. Final stope and pillar res- erve estimates (proved ore) are derived from designed ring tonnages and contoured accumula- tion for individual mining units, following more intensive sampling. Systematic grade control procedures have been adopted and individual stopes and pillars reconciled against mill production. The proved ore estimates have been found to com- pare favourably with the reconciled production.

Jan 1, 1979

By W Kendall

Ore sorting has the potential to reduce the feed to wet plants and in the case of complex orebodies that can significantly reduce the water, energy and reagent consumptions and resulting operating costs for the project. The application of ore sorters has sparked renewed interest and application in the precious and base metals mining industry in recent years as a result of the continuing development of new sensing technology and very fast information processing that is making ore sorters applicable to a much wider range of ores and larger scale operations. The application of ore sorters involves a range of trade-off decisions that have economic impact upon the benefits of ores sorting to the project under consideration. This paper will present some typical trade offs to be considered and their impact in a particular project setting. CITATION: Kendall, W, 2018. How economics drive the application of ore sorting, in Proceedings Complex Orebodies Conference 2018, pp 24–27 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The Kwademen Au deposit was discovered in 1977- 1978 following a regional geochemical survey carried out as part of a UNDP (United Nations Development Programme) and BUMIGEB (Bureau des Mines et de la Geologie du Burkina) mineral exploration programme. The climate in Burkina Faso is rather dry, with markedly seasonal rainfall averaging 800 mm pa in the Kwademen project area. The relief is low and the drainage poorly developed, so that soil sampling was preferred to stream sediment sampling. Rocks have been subjected to deep lateritic weathering, so that they are transformed into a mixture of Fe-oxides and kaolinite over depths varying between 30 and 40 m. At the regional stage, soil samples (30-40 cm depth) were collected a a 300 x 500 m grid. The Kwademen deposit was indicated by Cu, Zn, Mo and Au anomalies. Subsequently, an area of 9.2 km2 was covered by a detailed geochemical survey by soil (100 x 50 m) and auger sampling. The regional anomaly was fully confirmed, and subsequent drilling intersected mineralized ore shoots, justifying the establishment of an evaluation project led by the U.N.R.F. (United Nations Revolving Fund) in 1983- 1985.

Jan 1, 1988

Research cruises dedicated to seafloor hydrothermal activity along the Kermadec arc first began with the Sonne-135 expedition in 1998. This was followed by the worldÆs first systematic survey for venting along an arc during the 1999 NZAPLUME I expedition. Since then, cruises dedicated to mapping plumes along the Kermadec arc include NZAPLUME II (2002), NZAPLUME III (2004) and ROVARK (2007). In addition, the manned submersible cruises SWEEP Vents (2004) and NZASRoF (2005) utilised the Shinaki 6500 and Pisces V, respectively, to sample in detail select hydrothermalsystems for mineralised samples, rocks and vent fluids. The ROVARK (2007) cruise was the first to deploy an autonomous underwater vehicle (ABE) along the arc which surveyed Brothers volcano at a far greater resolution than had been done previously by ships on the sea surface. While these expeditions have largely been led by GNS Science, together with its collaborators from National Oceanic and Atmospheric Administration, Pacific Marine Environmental Laboratory (NOAA/PMEL), significant contributions have been made by other groups from various nations, exemplifying the global interest in seafloor hydrothermal activity associated with intraoceanic arcs. This is an&nbsp;ASTRACT&nbsp;only.&nbsp;A full-length paper was not&nbsp;prepared for this presentation.

Jan 1, 2008

By A Krishnan, C Garcia, I Luna-Berbesi

The discovery and exploration of deposits are progressively shifting to extremely remote regions and greater depths. As a result, exploration costs and the economic risk of a bad investment increase. Current megatrends in the exploration and mining sector indicate a growing demand for the implementation of automation, digitalisation, and machine learning techniques. The implementation of a multi-sensor-based core logging device (DMT, 2024) was done on 400 m of drill cores to optimise interdisciplinary processes in terms of time and quality, by using interlinked and consistent data in real-time, to obtain reliable predictions that support and speed up decision-making. The results are consistent with the laboratory data previously obtained by the mining company, highlighting the benefits of introducing ANCORELOG into their core logging procedures.

Sep 1, 2024

By W P. Breytenbach

"The phased application of statistical process control (SPC) infers that processes are classifiable as pre-SPC (or phase zero), phase I and phase II processes, with different objectives being pursued in the different phases. Phase zero processes, defined as processes affected by assignable causes of variation, are characterised as follows: out-of-control with unknown autocorrelation structure having an unknown statistical distribution not performing consistently on target with minimum variability potentially incapable of conforming to the product specifications. The objectives of phase I SPC is to obtain estimates of the mean (µ), variance (s2), probability density function (f(X)) and the autocorrelation structure, as well as transforming the process into a phase II process (defined as a process conforming to specifications and performing on target with minimum variability). As in any other type of research or pragmatic improvement intervention, sampling is required is to achieve these objectives. The challenge of deciding a phase I sampling plan is multifarious since it has to cope with the aforementioned effects of assignable causes and provide for rigour estimates of the unknown parameters. Furthermore, deciding sampling plans in phase I invariably presents a classical catch-22 situation: appropriate sampling is required to determine the autocorrelation structure of a variable, but knowledge of the autocorrelation structure is required to formulate an appropriate sampling plan. This paper suggests, for random variables, guidelines to formulate sampling plans, and presents a methodology to estimate the inherent process parameters of process variables and an approach to identify assignable causes in phase I.&nbsp;CITATION:Breytenbach, W P, 2014. Rational sampling and standard deviations for random variables in phase i application of statistical process control, in Proceedings Sampling 2014, pp 141–154 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 29, 2014

By E T. Baker, J A. Resing, S L. Walker, V Ferrini, F Martinez, R Haymon

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Enumerating active sea floor hydrothermal sites has been a challenge since their discovery almost 40 years ago. High-temperature hydrothermal sites are readily discoverable, primarily by detecting mineral-laden plumes, but working at these sites poses severe environmental and operational difficulties. Low-temperature vent fields, which may represent waning of venting from high-temperature systems, may be more accessible but are more difficult to locate. Over the last decade, however, oxidation-reduction potential (ORP; aka Eh) sensors capable of detecting minute concentrations of reduced hydrothermal chemicals have been successfully used to pinpoint such fields. In this extended abstract, we use ORP anomalies observed during continuous (towed sensor) plume surveys to estimate site frequency along four intermediate- to fast-spreading ridge sections. From these data, we estimate site frequencies between five and 16/100 km for these ridge sections. Previous camera surveys on the fast-spreading East Pacific Rise support these frequencies. These rates are much greater than the frequency of ~0.5–5/100 km, generally increasing with spreading rate, derived from well-surveyed ridge sections in the InterRidge database (InterRidge, 2014). The higher frequencies arise because ORP sensors are able to distinguish between sites as close as ~1 km and identify sites with negligible or no optical plume signal.CITATION:Baker, E T, Resing, J A, Martinez, F, Haymon, R, Walker, S L and Ferrini, V, 2015. How leaky are oceanic ridge axes? A new assessment of the spatial density of submarine hydrothermal discharge, in Proceedings PACRIM 2015 Congress, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Bush P. R, Hale M, Dixon C. J, Wheatley M. R

Barium anomalies in drainage sediments can act as indicators of barite mineralization and path- finders for lead-zinc mineralization. Their detection in an arid climate has been investigated in two areas of Saudi Arabia. At Rabigh, 150 km north of Jeddah, barium anomalies found in wadi sediments reflect barite veins which occupy Tertiary faults in Precambrian metavolcanics and granodiorite. In the Wadi ad Dawasir area, 650 km east of Jeddah, the sediments of wadis draining the Jabal Tuwayq escarpment have been found to contain anomalous concentrations of barium derived from diagenetic barite in the Sudair formation siltstones and shales. Barium dispersion in these wadis is predominantly clastic. Near to the source rocks, barium occurs in relatively coarse grains of barite. Owing to the three well-developed cleavages of barite, its crystals readily break into cleavage flakes during fluvial transport in flash floods; as a result, the longest anomalous dispersion trains are found in the 250 to 600 um fraction. Wadi sediments finer than 250 um have relatively constant and low barium contents, being dominantly composed of windblown sand.

Jan 1, 1988

By A C. Edwards

The Mesozoides of North-Eastern Asia represent a collage of exotic terranes which were accreted to the margins of the Siberian continent. In the Late Precambrian and Phanerozoic, the passive margin of the Siberian continent (the current north-east) broke up into a number of discrete fragments as a result of rifting events in the Riphean, Early and Middle Paleozoic. Rift related mineralisation includes stratiform and stratabound copper and base metal mineralisation in the structures of the Omulevka, Okhotsk and Prikolyma basement terranes, as well as along the edge of the Siberian continent in the Paleozoic sediments of the Verkhoyansk passive margin. During the Late Mesozoic the terranes were reassembled in a series of accretionary events. At the end of the Jurassic, the velocity of the Kula plate increased, and the opening of the Canadian Basin in the Arctic commenced, changing the vectors along which the Siberian and North American plates moved. Island arcs terranes were pushed back onto the Omolon super-terrane which was in turn pushed onto the Siberian Craton in a series of massive collisional events that resulted in the restructuring of the whole region. Numerous granitoids characterised by collisional and island arc chemistries with Au and accompanying Sn, and W mineralisation were emplaced. Mesothermal gold-quartz mineralisation was emplaced in a series of narrow belts that adjoin major crustal sutures and that spatially overlap belts of granitoids and zones of subgreenschist metamorphism. Each of these gold-quartz vein belts corresponds with a specific collisional phase. In the middle Cretaceous, the Okhotsk-Chukotka volcanic belt developed along the paleo-Pacific margin of the Siberian continent. Epithermal Au-Ag developed in the volcanics and shallow mesothermal Au-Ag-quartz and Au-Sb mineralisation developed in the Mesozoides. Porphyry and skarn style mineralisation developed in both the island arcs and in the continental Okhotsk-Chukotka Volcanic Belt.

Jan 1, 1999

During 1979 the writer had the privilege of interviewing about 50 people with varying degrees of involvement in the industrial arena and all of them in one way and another, had a part to play in the huge and intricate saga of Australian employee relations. They fell into the following&apos; categories Industrial Relations Officers/Managers Academics Politicians Union Officials Representatives of Employer Associations Senior Industrialists Commission Members (State and Federal) Sundry (Journalists, Government Officials). This paper seeks to give an account of their views on various aspects of industrial relations. The interviews conducted were all on a personal and confidential basis so it can be expected that sources will not be identified. Suffice it to say that this account represents, albeit in "potted" form, the opinions of some of the most experienced individuals in the country. It will be seen that in most of the vital areas there is a remarkable lack of consensus. It should be noted that this lack of consensus existed within each of the groups mentioned.

Jan 1, 1980

By S Sims, A Stradl, G Hope, B Lacouture

Column flotation cells have been installed in numerous base metal operations around the world. The majority of these cells utilise conventional air-only spargers to introduce air into the bottom of the column. The recent development of instruments to measure the bubble characteristics in these columns has provided a renewed understanding of column behaviour. These new tools provided insight into why the columns at Red Dog Mine had never performed up to expectations. After efforts to optimise the spargers failed to substantially change the bubble size and air efficiency, alternate sparger systems were investigated. The Metso Minerals CISA Microcel sparger system appeared promising and was selected for a full-scale plant trial. The Microcel sparger system was originally developed for the coal industry at the Virginia Centre for Coal and Minerals Processing. In October 2003, a Microcel was retrofitted into one of two 3.66 m diameter flotation columns in the zinc retreat circuit at Red Dog Mine. The operation of the two different sparger systems in parallel allowed a detailed comparison. This paper discusses the performance of the Microcel based on the data collected during several detailed surveys. Bubble size measurements carried out in the pulp zone using the McGill University bubble viewer showed a significant difference in bubble size. The mean Sauter diameter of the bubbles decreased from 3.4 mm for the jetting-type sparger to 1.9 mm for the Microcel sparger. The overall recovery and the recovery by size fraction for both valuable and gangue minerals were compared. Paired t-tests demonstrated that the Microcel column produced a higher concentrate grade (0.6 per cent zinc absolute) and a higher unit recovery (2.8 per cent zinc absolute) than the existing Canadian Process Technologies Inc (CPT) SlamJet column. These improvements provided a payback period of 1.5 months for the $109 000 investment.

Jan 1, 2005

By P W. Cleary, G K. Robinson, M D. Sinnott

Discrete element modelling (DEM) is a research tool that involves numerically solving the equations of motion of large numbers of particles. It can be very useful for investigating mechanisms that can lead to bias when extracting samples from material as it is carried on a conveyor belt or as it falls from the end of a conveyor belt. DEM is more realistic than conceptual models and mathematical models; but it is not as realistic as physical experimentation. Its primary advantages over physical experimentation are that it is cheaper and that it allows many factors to be varied while keeping other factors unchanged.This paper reviews our investigations of the performance of sampling systems by using DEM. The sampling systems investigated include falling-stream cutters, cross-belt cutters, Vezins and a device called a ætrue-beltÆ cutter, which is being developed. The purpose of the review is to explain what DEM has contributed to the theory and practice of sampling, and to indicate what it is likely to be able to contribute in the future.CITATION:Robinson, G K, Cleary, P W and Sinnott, M D, 2012. How discrete element modelling is influencing the theory and practice of sampling, in Proceedings Sampling 2012 , pp 15-20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

This paper describes the technical development of the Newman beneficiation plant over its 23 years of operation and how this development relates to the mine ore reserves of high-grade and low-grade ore. It also discusses the importance of the beneficiation product grades in the overall blending of shippable products from a range of mines to optimise overall ore resource utilisation. Also discussed is the importance of the ore reserve reconciliations in resource utilisation. Data is provided on the capacity and quality improvement results of the plant upgrade, carried out in 1999. This shows how the original capacity upgrade targets have been exceeded and the additional quality benefits that have been obtained from this capacity.

Jan 1, 2002