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Average annual growth in consumption of primary energy in Australia over the past 10 years has been 5·5 per cent compared to a world average of 4·1 per cent.Over the next 10 years growth rate is expected to increase to 6 per cent per annum due largely to the rapid development in the mineral processing industry.By the end of the 19705 natural gas is expected to supply more than 9 per cent of Australia's primary energy market. Coal will supply 40 per cent and petroleum products 47 per cent. Nuclear energy will make its appearance but will make only a small contribution in the period.Australia has adequate reserves of natural gas and coal to supply its needs in the 1970s and beyond. However the newly developed reserves of crude oil, while supplying 60-70 per cent of requirements in the initialyears, will need regular and sizable additions if they are to keep pace with the expanding consumption. For Australia to become self sufficient in the period 1970-1990 it is estimated that new discoveries will need to approximate ten times the volume of recoverable reserves found in Australia to date.

Jan 1, 1971

By C Fearon

This paper discusses the implementation of an underground rail haulage system during a major expansion of the Olympic Dam mine in 1998. The factors affecting the selection of rail haulage are discussed and details are provided on the rail system, which is designed to transport more than 10.5 million tonnes per annum (Mtpa). The reliability of the system during commissioning is discussed, including the decision to manufacture a ædummyÆ locomotive in order to keep the system operational. Finally, reliability improvements made both during and after commissioning are discussed with comments provided on the effectiveness of the system as it operates today.

Jan 1, 2005

By Middlebrook PD

The problems of education and research in the extractive metallurgy area are being tackled by the University of Melbourne through activities centring on the Department of Chemical Engineering. The establishment of the G.K. Williams Laboratory and the enhance- ment of the teaching of material relevant to extractive metallurgy in the Chemical Engineering course aim-at providing graduates and experienced researchers for the industry and at providing a strong research group carrying out industrially significant research in the area of pyrometallurgy.

Jan 1, 1986

Over the past seven years, a combination of New Zealand-, Australian- and German-led research voyages using the research vessels Tangaroa, Southern Surveyor, and Sonne respectively, have revolutionised our understanding of the Kermadec-Tonga arc-backarc systems. This convergent margin is the most seismically-active subduction zone system on Earth with convergence rates steadily increasing northwards from the Hikurangi Trench to ~250 mm/year at northern Tonga. In combination with the intra-oceanic setting, factors potentially producing magmatic, tectonic, and hydrothermal variability in this system include an increase in potentially subductable sediment northwards along-strike, intersection of the Louisville Ridge (hot-spot chain) and Osbourn Trough (paleo-spreading centre) with the arc at ~25¦S, and the possibility of Samoan (hot-spot) plume ingression in the northern Lau Basin. The bulk of the magmatism is submarine; whereas only a few emergent (some transient) volcanic islands exist, about 80 submarine volcanic centres of significant size (>1000 m above surrounding sea floor) are present between White Island in the south to north of Tafahi in Tonga. About 35 per cent of these centres are hydrothermally active. Important petrogenetic features of the volcanic rocks along this arc system are the abundance of rhyolite (some quartz-amphibole-bearing), and the outcrop of primitive olivine-clinopyroxene-phyric basalts in satellite cones of the major edifices. Many of the edifices consist of complex caldera systems. Eruptions from and degradation of these edifices were probably tsunamigenic. Many of the hydrothermal systems developed within the edifices are likely destroyed during the sector collapses which are the characteristic edifice degradation mode. There are three backarc spreading systems along this margin: the Havre Trough, Valu Fa-Eastern Lau Spreading Centre, and the nascent Fonualei Rifts. The latter are particularly notable in having captured the entire suprasubduction zone magmatic flux for a distance of about 150 km, shutting down the adjacent volcanic front arc volcanoes.

Jan 1, 2005

By S A. Prevec

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Traditional models employed to genetically link associated chromite and platinum-group elements have favoured crustal contamination as the primary process for inducing sulfide and oxide saturation. The association of chromite ores with crustal contamination is well established in the literature. However, in the 1970s (cf Irvine, 1973, 1975), Irvine demonstrated that crustal contamination was in fact problematic as a tool for inducing chromite precipitation in mafic to ultramafic magmas. His results are re-examined here, along with some attempts to reconcile them with the effects of adding Fe to the models. It is concluded that crustal contamination is indeed problematic based on phase relationships alone. However, the role of fluids as a compensating agent is evaluated, which may explain why crustal contamination may indeed facilitate oxide and sulfide precipitation.CITATION:Prevec, S A, 2015. Chromite and platinum-group elements coprecipitation by crustal contamination or magma mixing revisited – genetic and exploration implications, in Proceedings PACRIM 2015 Congress, pp 311–316 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By C R. Stanley, D Lawie

The measurement of error in assays collected as part of a mineral exploration program or mining operation, including errors introduced during sampling, sample preparation, or geochemical analysis, historically has been undertaken in a variety of ways. Different parameters have been used to describe the magnitude of relative error and each of these parameters is related to the standard measure of relative error, the coefficient of variation. Calculation of the coefficient of variation can be undertaken in a variety of ways; however, only one produces unbiased estimates of measurement error: the root mean square coefficient of variation calculated from the individual coefficients of variation. CITATION:Lawie, D and Stanley, C R, 2012. Average relative error in geochemical determinations - Clarification, calculation and a plea for consistency, in Proceedings Sampling 2012 , pp 181-184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By S La Brooy, C Fountain

Throughout its history the mining industry has focused on the highest-grade deposits sited in the most convenient locations. The burgeoning global population and higher standards of living not only increase the demand for mineral products but also make it harder to mine and process them. The future will include the development of lower-grade, more complex orebodies, and orebodies in difficult locations. The industry will be expected to provide for humanityÆs needs while reducing its environmental footprint and maintaining profitability. This paper reviews some of the likely adaptations in mineral processing that will occur over the next 20 years. The challenges inherent in adapting to lower grade and more complex materials might be exacerbated by such factors as the availability of water and low-cost energy. In underground mining, higher energy costs are likely to foster further developments in underground preconcentration, especially for ores that can be upgraded at relatively coarse sizes. The adoption of underground crushing could also render material amenable to semi-dry preconcentration options such as might be achieved by the rotary classifier developed by CSIRO and being commercialised by RCR Tomlinson, or more modern versions of the hand-sorting of ore that use sensors based on colour or other suitable rock properties. The cement industry and some gold roasters have used the alternative of dry grinding and classification, which might also have a part to play in dry processing. There is also likely to be increased interest in options such as in situ leaching that further minimise the surface disturbance. Underground operations will have to balance the energy savings from reducing the amount of material brought to the surface and reduced surface disturbance against the practical limitations of installing and maintaining processing equipment underground. On the other hand, surface disturbance and energy issues in open cut operations will be balanced by potentially lower mining costs and higher overall recovery from the deposit.

Jan 1, 2008

By Newell RB

Grinding circuits are used in most mineral processing plants. Their widespread application makes the efficient running of the circuits essential to almost all resource projects. This paper will show that, with the application of modern multivariable control techniques, improved plant performance can be obtained when compared with conventional single loop control strategies. Results are presented for a simulated closed-circuit ball mill.The grinding circuit was controlled using the rod-mill water and primary and secondary sump dilution flowrates as the manipulated variables. Variables controlled were the primary cyclone feed flowrate, the primary cyclone feed density and the particle-size measurement (percentage smaller than 75 um).

Jan 1, 1985

By P Gleeson, J Coombes, P Suresh, T McLennan

The last 20 years have seen a dramatic rise in the use of 3D visualisation and modelling for geological data, but there has been relatively little effort to do the same for the variogram models that underpin the standard estimation algorithms used by the mining industry.For kriging, one of the most used geostatistical estimation methods, specifying a variogram model is a critical part of the modelling process. Experimental variography is the primary method for approximating the theoretical variogram function from the available sample data, and then determining an appropriate variogram model from the approximations.The traditional tools used for experimental variography are limited to looking at subsets of the data and are often presented without reference to geographic space and geology. It can be difficult to know what input data is being used for a particular experimental variogram, and whether there is enough support in the experimental variograms to propose an appropriate model.To overcome these limitations, an innovative approach called situational variography has been proposed that visualises variograms in 3D alongside contextual geological and geometric data. Presenting variograms in this manner aids understanding of how the spatial variance relates to the underlying data.A 3D extension of the 2D radial variogram maps will be investigated which allows for dynamic exploration of the full experimental variogram cloud. These 3D experimental variograms are much easier to visualise situationally.A workflow for situational variography will be outlined and the advantages of the situational approach will be illustrated using a porphyry copper deposit.CITATION:Gleeson, P, McLennan, T, Suresh, P and Coombes, J, 2017. Situational 3D variography – determining the variogram in the context of geology, in Proceedings Tenth International Mining Geology Conference 2017, pp 191–198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By N Madani, Y Abildin, E Topal

Mine planning is a crucial part of all mining industry projects, and nowadays, geometallurgical mapping through advanced computer technologies provides an opportunity to involve metallurgical responses of a deposit into 3D block model in order to optimise mine planning activities, especially for production forecasting. Including these metallurgical parameters apart from traditional geology and grade-based attributes into resource modelling leads to an extensive approximation for the economic maximisation of mine production due to better forecasting, planning and increasing certainty and the reliability of the resource model (Macfarlane and Williams, 2014). Commonly, geostatistical techniques and algorithms are used to produce models with the high resolution (Brissette et al. 2014; Deutsch et al. 2014; Tolosana-Delgado et al. 2015). The accuracy of the modelling procedure deeply depends on a reliable block model, produced by spatial analysis of corresponding variables that define the geological, metallurgical, mineralogical and chemical behaviour of the deposit. However, there are special cases, where the application of enhanced geostatistical methods is required, to solve the occurred difficulties between variables with multivariate complexities. For example, in oxide copper deposits, the soluble copper grade is a percentage of total copper grade and recoverable by heap leaching processes (Emery, 2012; Hosseini and Asghari, 2015). Hence, the joint spatial modelling of these variables has two difficulties.CITATION:Abildin, Y, Madani, N and Topal, E, 2018. Forecast the mineral processing destinations based on spatial interpolation of geometallurgical variables, in Proceedings Complex Orebodies Conference 2018, pp 2–5 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

A study of the bacterial oxidation of naturally occurring high-purity sulphide minerals (FeS2, Fel_xS, CuFeS2, Cu2S) has been conducted using a mesophilic strain of T. 6ejtAooLcdcth4. As well as metal analyses and solution pH, partitioning of sulphide sulphur into elemental sulphur and sulphate ion has been monitored. Partially oxidised sulphide substrates have been characterised at regular time intervals by X-ray diffraction methods and extra-cellular organic compounds reporting into leach solution have been identified by'thin layer chromatography. The results indicate that the S¦/SO4 2 partitioning of the sulphide substrates is independent of cell inoculum size and initial pulp density and varies with solution pH, Eh, leaching time and mineralogical properties of the individual sulphide minerals. The signifi- cance of results for applications in selective flotation, coal desulphurisation and agglomera- tion has been outlined.

Jan 1, 1984

By T P. Tafirenyika, K C. Corin, C T. O’Connor

There is a growing demand for copper driven by its applications in renewable energy and electric vehicles. Sulfide ores are an important source of copper. Flotation is a critical front-end process used to remove gangue minerals and concentrate the copper minerals. The electrochemical activity of sulfide minerals contributes to their overall activity in the flotation pulp. The mineral rest potential dictates how collectors interact with the mineral surface, and hence ultimately on the flotation response. Dissolved oxygen, (DO), pH, redox potential (Eh) and water composition and ionic strength are also significant in controlling flotation performance. The aim of this investigation was to determine the influence of the electrochemical environment both during milling and flotation on the flotation behaviour of bornite and chalcocite. For this investigation, the interactions of collector with bornite and chalcocite were studied using synthetic plant water (SPW1) and deionised water (DIW) at 5 different pH levels. Sodium isobutyl xanthate (SIBX) was used both in microflotation, collector adsorption and zeta potential tests.

Aug 24, 2022

By Waldram JT

The Kelsey Centrifugal Jig incorpo- rates the principles of operation of a conventional mineral jig, at the same time utilising high centrifugal forces to extend concentration to very fine heavy minerals. The main operating variables which are adjusted to control processing of different types of material are centrifugal force, ragging material and size distribution. Pilot plant trials have been under- taken to examine concentration of a mineral sand in which the heavy mineral particles occur mainly in the minus 0.075 plus 0.032 mm size range. Stage recoveries of greater than 90% were achieved at concentration factors of up to 2, although lower recoveries were obtained with higher concentration factors. A final concentrate containing 65% heavy minerals was obtained.

Jan 1, 1986

By Plyley WF

Kidston Gold Mine is a 3.5 million tonnes per year operation located 280 kilometres west of Townsville, Queensland. Kidston's ore body consists of 44.3 million tonnes graded at 1.79 grams per tonne gold and 2.22 grams per tonne silver. Full production commenced in March, 1985. During the remainder of 1985, Kidston milled 3.77 million tonnes of ore and produced 213,614 ounces of gold.The ore is comprised of granodiorite, polymictic and volcanic breccias. The degree of oxidation of the rock influences the milling capacity and therefore determines the cut-off grade; ore is categorised as oxide, transition and fresh. The milling rates are 15,400, 12,000 and 9,600 tonnes per day for oxide, transition and fresh ore respectively.The ore is treated in a conventional cyanidation/ carbon-in-pulp plant (CIP). The plant consists of a primary crusher, semi-autogenous grinding (SAG) and ball mills, leach circuit and carbon-in-pulp circuit. Carbon stripping and dore smelting are done on site. The major difference between the Kidston plant and other Australian CIP plants is that a cyclone separation and washing circuit rejects half of the dry tonnage as a sand tail prior to CIP treatment. This difference allows the CIP circuit at Ki.dston to be smaller and makes the CIP less sensitive to the grind circuit product size.

Jan 1, 1986

By B Crompton, A Berghorst, G Knox

Laboratory-based dynamic testing provides an invaluable tool in the development of rock bolts for use in highly stressed, burst prone rock masses. While in most cases the laboratory-based test method is not a direct comparison to an in-situ installation due to the purely axial loading and variations in boundary conditions, it does provide an indication of the performance of the tendon system under dynamic loading. The aim of the research described in this paper is to provide an understanding of the effect of the impact velocity of the impact mass during a laboratory-based dynamic test. Understanding the effect of boundary conditions of laboratory testing will improve Geotechnical Engineers understanding of the performance in an in-situ installation. In addition, due to the limited number of dynamic test facilities, an understanding of the effects of the boundary conditions will aid in the comparison of test results for different products from different test facilities. The research was conducted using an impact tester, whereby a known mass is raised to a known height defining the kinetic energy and velocity of the mass at the point of impact with the test sample after release. The impact velocity was varied between 2.7 m/s and 5.4 m/s, while the kinetic energy of the mass was maintained at 11.5 kJ. While a correlation between the impact velocity and strain rate of the system tested was established, due to the properties of the system tested, the range of impact velocity on which dynamic tests were conducted was insufficient to result in a considerable change in the average impact load, the cumulative proximal displacement and the cumulative maximum energy absorbed over multiple impulse. However, due to the reduction in the momentum of the impact mass the impact duration and displacement during each impulse in the series of impulses reduced. CITATION:Knox, G, Berghorst, A and Crompton, B, 2018. The relationship between the magnitude of impact velocity per impulse and cumulative absorbed energy capacity of a rock bolt, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 160–169 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

At many locations in Australia the decommissioning of mining operations will require the disposal of excess water. If the water is contaminated its disposal may be restricted by government guidelines. The timing of water disposal may be critical to the schedule of close-out. The uncertainty of the annual rainfall input to the water storage and disposal system may determine the success or failure of close-out. The uncertainty associated with any outcome can be used to determine the reliability of the system, or inversely its risk. The technique of Monte Carlo simulation, using the uncertainty in annual rainfall, is applied to quantify the risks associated with water disposal as part of the requirements for close-out in two case studies. In both case studies it is assumed that water disposal is via evaporation only. The first case study is the Nabarlek operation, located about 270 km east of Darwin. This project is required to complete the engineering work associated with its close-out by December 1995. The second study investigates the situation of close-out for the Ranger Uranium Mine, about 250 km east of Darwin. It should be noted that the Ranger mine was examined as part of the annual update of its contingency rehabilitation plan and the probability of implementing the plan is extremely small. The probability of success for the Nabarlek case varied from less than ten per cent to greater than 95 per cent depending on the management strategy. Four possible strategies were investigated for the Ranger mine with the chance of success varying between 20 and 95 per cent. The estimation of the evaporation rate and the area allocated to evaporation was critical in both cases. By applying seasonally based evaporation pan coefficients determined on site, rather than an average monthly value of 0.75, the chance of success was improved by up to 35 per cent for Ranger. Simulation modelling is able to provide information on the likely response of mine water management systems and the level of risk. This information is required to efficiently plan and manage the disposal of water for close-out.

Jan 1, 1994

Existing production facilities are constantly looking at ways to increase capacity. Many recent solutions have focused on the implementation of capital and infrastructure projects. It is accepted that capital expansions are frequently necessary for production gains; however, in many cases existing assets have the potential to deliver substantially better throughput than they are currently achieving. By focusing on automation of production control systems, production reporting and business processes substantial gains can be achieved utilising existing assets. This potential can be realised quickly and has been proven across several sites and industries. In the Pilbara region of Western Australia throughput gains of between two per cent and 25 per cent (translating to millions of tonnes per annum) have been achieved from existing assets using the methodologies discussed. The improvement process involves evaluating the entire production chain from the time the ore arrives at the plant to the time it is dispatched. A technical evaluation of the performance of the control system and plant automation interfaces to upstream and downstream processes is conducted. The relationship of these processes to the business systems and the human interface to the systems is reviewed to ensure a complete picture of the system is understood. Technical evaluation targets include: individual equipment operation, the engineering level of control systems, feed controls, etc; managing recirculating loads, surge capacities, dynamic inventories as well as management of in-feed systems and integration into yard and out-feed systems; and communication flow between control and other systems, data alignment between rail and shipping schedules, yard systems, sales systems and maintenance systems including such fundamentals as truck dispatch links to plant control. In parallel with the technical evaluation, business system evaluation takes place, including analysis of the operational systems, methods and personnel.

Jan 1, 2007

Modelling of Synergistic Effect of Cyanex 302 and D2EHPA in Zinc Solvent Extraction A comprehensive model is presented to predict the synergistic effect of D2EHPA and Cyanex 302 on co-extraction of zinc and manganese. The experimental results indicated that pH, temperature and the extractants ratio have strong effects on the extraction process. Correlations were proposed to predict the distribution coefficient of zinc and manganese between two phases at different conditions by multiple linear regression. The correlations were simplified by eliminating less important terms by analysis of variance. Optimum conditions (ie pH, temperature, extractants ratio and aqueous to oil phase volumetric ratio) for obtaining maximum separation of zinc from manganese at different zinc concentrations and number of extraction stages were determined. For finding the optimum condition genetic algorithm was used. Comparison the model estimations and the experimental data show that the presented model has good ability to predict the behaviours of zinc extraction system over Cyanex 302 and D2EHPA.

Sep 13, 2010

By D Connelly

The Iron Road Limited Central Eyre Iron Project (CEIP) area, located on the Eyre Peninsula of South Australia, covers extensive Archaean iron formations that occur as coarse-grained magnetite bearing gneiss. The cumulative strike length, estimated from aeromagnetic data, is at least 95 km.The project is located in a grain growing area 185 km west of the existing iron ore and steel making operations of OneSteel at Whyalla. A narrow gauge railway built to transport agricultural products to the deep-water port of Port Lincoln, 175 km to the south, traverses the project area. A number of well-serviced rural townships are located nearby. Current activities include resource expansion drilling, extensive metallurgical test work, community consultation and a Prefeasibility Study (PFS) that commenced in April 2010.The PFS has encompassed the Central Eyre Iron Project, comprising the three significant iron occurrences (Warramboo, Kopi and Hambidge) and was completed in early 2011. Extensive test work programs and metallurgical modelling confirmed viable process options for the project, using simple off the shelf processing technology.Preconcentration by coarse cobbing yielded promising results, and is the key to reducing not only the capital expenditure but also the operating cost, in particular the power cost, which is the highest operating cost component of a magnetite benefi ciation plant. The ore is also amendable to high pressure grinding rolls (HPGR) processing. This offers a potential for further reduction of the energy requirements.Test work also confirmed that a high grade blast furnace quality concentrate (~68 per cent Fe) can be produced at a relatively coarse grind (P80 106 µm).

Jul 11, 2011

Copper was first produced in Australia in 1844, at the Kapunda Mine in South Australia, and, by 18i>0, production exceeded 2,000 tons of copper a year. Output increased ,steadily, reaching a peak of 14,00Qo tons a year in 1867 and 1868, when the Burra Burra and Kapunda Mines in South Australia and the Peak Downs Moine at Clermont, Queensland, were at the height of their production. At this period, Australian copper formed a considerable percentage of the world's supply, its output equalling, for a short time, that of the United States. Production declined to between 3,000 and 4,000 tons a year after the closing of' these three mines between 18717 and 1879, and, at this stage, the Australian output came chiefly from the Wallatoo and Moonta mines in South Australia. About 19000, it began to rise again, with the extension of the railway to the copper fields of Chillagoe and Cloncurry, and, between 1905 and 1912, was at its greatest, with a maximum of 47,774 tons of copper in 1912. During this period, Australia contributed 4,7 per cent. of the world's annual production, and ranked among the six major copper-producing countries of the world (Table 1).

Jan 1, 1943