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By Mills R, Shannon W. T, Finch J

As an extension to investigations into methods of upgrading the Iitania content of ilmenite concentrate from beach sands using 100 g/day, a small pilot plant treating 23 kg/ day of ilmenite was used.In the pilot plant the iron oxide in the ilmenite was reduced to iron at 1200°C using carbon (coal/char) without melting the material, using a tunnel kiln heating cycle, the charges contained in saggars, The iron was then separated from the titania fraction by ball milling, wet magnetic separation, and screening. The resulting magnetic product was high in iron (about 80 per cent Fe) and the non-magnetic product high intitania (about 70 per cent TiO2).From this trial sufficient data were obtained to enable the preparation of a flow sheet for a plant producing 62,300 tonnes/year total products, and an estimate of costs to be made. This has shown that for an estimatedcapital expenditure of nearly $6,000,000 and annual production costs of about $4,000,000, the cost per tonne of high titania product (76 per cent TiO2) would be nearly $70.

Jan 1, 1977

Identifying Opportunities to Reduce the Consumption of Energy Across Mineral Processing Plants

Sep 13, 2010

By C Roche, G M. Mudd

The Morobe Province of central Papua New Guinea (PNG) has been mined for gold for nearly a century, although it is only in the past decade that large-scale modern mining commenced. The Hidden Valley gold-silver project began construction in mid-2006 and production by August 2009, and is located in the mountains above Wau in the headwaters of the Watut River. The mine is owned and operated by the Morobe Mining Joint Venture (MMJV), which also owns the Wafi-Golpu project, comprising the Wafi gold deposit and Golpu copper-gold deposit, situated in the Watut River Valley. Together they represent a potential mine of the scale of Ok Tedi or Bougainville or bigger. The MMJV is owned in equal shares by Newcrest Mining from Australia and Harmony Gold from South Africa. Although Hidden Valley was the first large-scale mine in PNG to engineer and build a tailings storage facility, poor environmental management during construction and early operations led to significant erosion of waste rock and sedimentation impacts throughout the ~200 km length of the Watut River. Since then, substantial efforts have been made to improve environmental management, especially waste rock placement and storage and water quality management. While the impacts from the Hidden Valley project appear to be reducing, the saga has heightened concerns by many along the Watut River and across PNG about ongoing impacts from mining.This paper presents the results of an ongoing project in the Morobe Province conducted by the Mineral Policy Institute examining the historical, current and future impacts of mining, including community views, social and environmental impacts and the monitoring and regulation of mining. Overall, there is a clear need to more fully integrate social and environmental issues into life-of-mine planning and go above and beyond regulatory requirements. In this way, some of the lessons learnt – by the community, MMJV and government – can be incorporated before, during and long after mining.CITATION:Mudd, G M and Roche, C, ?2014. Mining in Morobe, Papua New Guinea – impacts, assurance and self-determination, in Proceedings Life-of-Mine 2014 , pp 313–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By King R. L

Low-enthalpy geothermal groundwater resources occur at relatively shallow depths in the Upper Cretaceous/1'ertiary sedimentary sequence in the on-shore Gippsland Basin. The main stratigraphic unit containing hot groundwater is the Latrobe Group. Groundwater temperatures in the range 30 to 70¦C have been recorded from depths between 500 and 1000 m. The hottest groundwater is in the Latrobe Valley and Lake Wellington depressions. Geothermal gradients in these areas range from less than 2¦C/100 m to over 10¦C/100 m (compared to a world average of about 3¦C/100 m). A number of theories have been advanced to explain the geothermal anomalies including exothermic reaction such as oxidation of coal, mixing with deeper, hotter groundwater and high geothermal fluxes along fault zones. Variations in geothermal gradients can also result from type and thickness (and hence thermal conductivities) of the sedimentary pile, depth to consolidated basement rocks, and influence of groundwater flow patterns including proximity to recharge zones. The hot groundwater in the Gippsland Basin has substantial potential as a source of energy for direct heat applications such as process heating, space and water heating for buildings, and agricultural and aquaculture. Geothermal energy has a number of environmental advantages over traditional sources of energy. It is clean, safe, causes minimal land disturbances and in most cases is naturally renewable.

Jan 1, 1992

The objectives of mining grade control are presented and examples of the techniques used in various open pit and underground mines are used to define the attributes of good grade control. Reasons are discussed for the success of various improved practices. The progressive development of grade control is presented and the balance between quantitative and qualitative data is analysed. The skills and resources required for grade control on mine sites that are using best practice are also presented. A number of problems in grade control have been solved recently however there are still issues that need to be addressed. Examination of the grade control process frequently stops after sample quality has been examined. There is much more beyond this that can now be optimised using conditional simulation models. Other future directions of mining grade control are also suggested. An extensive bibliography of published papers on grade control is included that will be maintained and updated on a website.

Jan 1, 2000

Lead isotope measurements indicate that lead from the A.B.H. Consols mine and two transgressive veins in Browne's shaft is "Thackaringa" type and not "Broken Hill" type.

Jan 1, 1970

By J Lapwood, S Pal, M Pascoe

The devastating failure of Dam I at the Corrego do Feijao iron ore mine near Brumadinho in Brazil on 25th January 2019 left at least 270 people dead or missing. In the immediate aftermath of this event, many mining companies commenced reviews of their tailings and water storage facilities (T&WSFs), and Rio Tinto was no exception. Rio Tinto has an interest in over 250 T&WSFs across 47 sites in 13 countries as owner-operator, as managing JV partner, and through non-managed partnerships and other ownership arrangements; T&WSF experts from Rio Tinto’s Surface Mining Centre of Excellence visited the sites in order to complete Technical Risk Reviews of each facility. These reviews looked beyond the day-to-day operational aspects of T&WSF management, and the site’s compliance with local regulations and Rio Tinto’s internal D5 Standard – Management of tailings and water storage facilities, in order to provide a strategic, second line of assurance perspective. The reviews focused on design and construction; operational controls; risk control framework; and competencies and capabilities of personnel involved in the design, operation and closure of the facilities. Additional activities were carried out in parallel with these reviews, including the development of a consistent approach to dam break studies; the public disclosure of information on Rio Tinto’s tailings storage facilities and their management; and contribution to external programs such as the initiatives being co-ordinated by the International Committee on Mining and Metals. This paper provides an overview of the tailings and water storage assurance work undertaken by Rio Tinto’s Surface Mining Centre of Excellence Tailings Validation Taskforce to date; work that will continue to improve governance and assurance for all of Rio Tinto’s T&WSF.

Jul 1, 2021

The mineralogy of nickel slags from the flash smelter of Western Mining Corporation Ltd. at Kalgoorlie was studied. Residual magnesium silicates in the sulphide concentrates raise the melting point of the slag and result in the formation of magnesium-rich olivines. Addition of lime lowered the melting point, and, in slowly cooled slags, resulted in the formation of a pyroxene.Magnetite and sulphides were also present in all slags.The converter slags contained an olivine near fayalite in composition, together with wiistite, magnetite, and a little sulphide.Accretions from the hearth of the flash furnace were largely composed of magnetite with subsidiary olivine similar in composition to those of the flash furnace slags.Wall deposits, however, were largely composed of nickel ferrite and nickel-iron olivines.

Jan 1, 1976

By Patterson B. G

The small party of mining men who formed the original Mount Morgan Syndicate in 1882, commenced operations on the top of the mountain with what were practically nothing more than small hillside quarries, It was not until 1891 that underground stoping began, and open-cut mining therefore commenced with the commencement of operations. This hillside quarrying, however, seems to have been quite haphazard and unsystematic ; there is no trace or sign of any properly devised mining scheme. This can be seen plainly enough from an examination of old mine plans; for in less than five years after stoping was; adopted, the open-cut was down into the stoped-out ground. The following table, prepared from these old plans, shows the downward trend of the excavation in the past fiftyseven years:-

Jan 1, 1939

By OÆBrien R. T

A small static bed was used to study the thermal cycles required for the heat hardening of pellets based on synthetic magnetite concentrates and a naturally fine hematite. This apparatus can be employed to yield broad process data for the design of a recuperative strand system operating on the magnetite concentrates.Various alternatives are given for a process to heat harden the hematite ore but a preference is given to the production of a self fluxing pellet. Bond types and general mineralogical structures are interpreted against the optimum firing cycle necessary to produce a defined quality of pellet.INTRODUCTIONThe work reported in this paper extends that on the "Heat Hardening of Artificial Magnetite Pellets", which was described at the International Symposium on Agglomeration, sponsored by the American Institute of Mining, Metallurgical and Petroleum Engineers at Philadelphia, U.S.A. in April 1961. Whereas that work was of a more basic nature, serving to illustrate the suitability of artificial magnetites with various admixtures, to the application of heat hardened pellets, on this occasion the aim is to illustrate the procedures which were used to establish the dimensions of commercial recuperative strands for Australian raw materials.The nature of the pellet feed, Le. relatively uniform spheres of + i in.-Yi6 in. diameter, makes it possible to use small scale static pots for test work. By the use of a closed system and the measurement of suctions, gas flows...

Jan 1, 1963

By P B. Card

"The website www.economicevaluation.com.au, which had its origins at the Project Evaluation Conference 2009, provides a free way for industry professionals to teach themselves economic evaluation. At its core is a set of fast-moving modules and three worked examples.The website recognises that economic evaluation is a discipline with a hierarchy of three levels:decision-makingevaluating the project/businesshands-on modelling.There are a set of modules for each level that describe the concepts and activities in detail. These emphasise that the most important and rewarding work is the evaluation of Level 2. The economic model created in Level 3 is merely a working tool and should not become a sophisticated ‘trophy’ in Excel that only one or two people can comfortably use.Hands-on modelling contains three sets of practices designed to make any model rigorous and intuitive so that it can be easily understood and used by others in the project team. Even if the model develops into a long, detailed and complex workbook, it should remain easy to follow and be intuitive. The website advocates freedom to devise any architecture that best suits the project under study, but promotes rigour through the following practices:four cash streams and graphsthree architectures – concept, prefeasibility and feasibilitysix principles.The modules in the Level 2 evaluation use conversational language to describe in detail the broad range of activities needed to properly understand and characterise a project/business. It stresses that net present value is nothing more than the mathematical treatment of a whole set of opinions, is not an absolute truth and is only a fraction of the evaluation process. The modules describe in detail the range of economic metrics that should be computed and the full spectrum of equally important characterisations required to make the decision in Level 3.CITATION:Card, P B, 2016. Teach yourself economic evaluation, in Proceedings Project Evaluation 2016, pp 160–171 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By Madgwick J. C

A novel, microaerobic, heterotrophic microbial leaching system for manganese dioxide is described. Mixed natural microflora were enriched by addition of sugars and crude plant nutrItIOnal supplements. Between 84 and 104 mg MnH was solubilized per gram sugar at I per cent (w/v) concentrations for fructose and galactose in the presence of 0.03 per cent w/v dried microalgae (a Chlamydomonas species). Some 42 per cent soluble manganese was dissolved by microbial action on MnO, (3 per cent (w/v) pulp density) using a 10 per cent (w/v) molasses growth substrate.

Jan 1, 1983

By J B. Gemmell, D R. Cooke

Recent mapping at the Kelian epithermal gold deposit in East Kalimantan, Indonesia has delineated intrusive and extrusive-phreatomagmatic breccias, their magmatic roots, and late-stage endogenous domes of a maar-diatreme complex. The Kelian epithermal system is characterised by a wide variety of mineralised and unmineralised breccias, which include tectonic, hydrothermal, phreatic and phreatomagmatic varieties. Phreatomagmatic breccias and associated igneous rocks post-date early stage alteration and mineralisation, and pre-date main stage precious and base-metal mineralisation. This study emphasises the spatial, temporal and genetic links that have been drawn between diatremes and both epithermal and porphyry systems in volcano-plutonic arcs.

Jan 1, 1999

By G W. Wilson, M Aubertin

A desulfurised tailings cover was installed at the Detour Lake Mine in Ontario, Canada, to reduce oxygen penetration into the underlying sulfidic tailings. The cover ranges from one to 1.5 m in thickness and was intended to maintain high water saturation to reduce oxygen diffusion and consume oxygen by oxidation of the residual sulfide minerals. The tailings impoundment was instrumented to measure climatic parameters, water levels and water content profiles within the tailings and single-layer cover. One year of monitoring data was collected. Additional tailings samples were obtained for geotechnical and geochemical characterisation. The average grain size of the cover material was found to be coarser than the underlying tailings. Monitoring also indicated that air entry values of the cover material were lower than the tailings. Numerical modelling was conducted on the cover to predict water content profiles under varying climate conditions together with the depth of oxygen penetration and diffusive oxygen fluxes. Estimates of the diffusion coefficient and kinetic oxidation rates from field data compared well with values obtained by laboratory measurements. Numerical simulations indicate water saturations of less than 85 per cent can be expected under varying climate conditions. Predicted oxygen flux rates through the desulfurised cover over tailings with high acid potential indicate low flux rates reaching these tailings due to either consumption of oxygen by residual sulfur within the cover or saturation of the underlying tailings.

Jan 1, 2003

The achievement of high availability of the Grey River Gold Mining Limited's alluvial gold dredge is a tortuous task which will rely upon the dedication of all staff employed at Grey River Gold Mining Limited (GRGML). The persistent adoption of new technology and better operating procedures, combined with a strong commitment to preventative and predictive maintenance, is necessary. The Grey River Gold Mining Limited alluvial gold dredge is operating in a relatively low grade alluvial gold deposit and hence relies on a high throughput of ore to be profitable. To achieve the required high material throughput the dredge incorporates an overburden removal system which operates simultaneously with a conventional bucketline system.   The overburden system incorporates a cutter wheel and suction pump configuration which is dedicated to removing the low grade (5 mg gold/m3 gravel) overburden. The bucketline conveys the richer grade payzone gravels (up to 890 mg/m3 gravel) to the recovery plant mounted onboard the dredge. The horizon for the overburden system approximates 15 m and the payzone terminates at the interface of the old man rock and the alluvial gravels at a variable depth averaging 22 m.   From a mechanical engineering perspective the dredge is a machine comprised of two materials handling systems which are controlled by Operations Staff and electronic process control systems.   The availability of such a materials handling system is a function of four variables: 1. The environment that the machine operates in. 2. The ability of the people operating the machine. 3. The design of the mechanisms, the configuration that they are grouped in and the effectiveness of the process control systems which control the mechanisms. 4. The procedures utilised to predict the performance of the machines and the skill of staff to analyse that data and carry out effective maintenance.

Jan 1, 1989

The Chamber of Minerals and Energy of Western Australia Inc (CME) is the peak resources sector representative body in Western Australia. The paper gives a summary of the role and objectives of the CME, including its history, structure and key program areas. Particular attention is given to the role of the CME in the Eastern Goldfields of Western Australia. The paper details the types of CME membership that are currently in existence. The paper argues that a strong and vibrant CME is vital to secure the resources sectorÆs growth and development in future years.

Jan 1, 2006

The solvent extraction section of an old Uranium Plant in the Vaal River region (North West Province in South Africa) produced a substance called CRUD (Chalk River Unidentified Deposit) that formed within the aqueous/organic interface of the settler of the solvent extraction circuit. The CRUD was deposited together with gold tailings to the tailings dam many years ago. Previous research done on the CRUD confirmed that exposed CRUD leaches Mn and Ni at concentrations that are well above their acceptable risk limits as well as Zn that leaches at concentrations that are slightly lower than its acceptable risk limit. Soil washing and bioremediation technologies were employed to treat the contaminated soil.   Various laboratory test work and the pilot scale studies were conducted in parallel with each other and the results of the laboratory studies were used to determine critical parameters. Four lixiviants, ie sulfuric acid, acetic acid, oxalic acid and ethylene diamine acetic acid were tested at three concentration levels ie 0.001 M, 0.0001 M and 0.00001 M, respectively. Column tests showed that the leaching of the heavy metals increases as the soil porosity increases. Silica sand was added to increase porosity of the contaminated soil. Highest Mn removal was achieved mainly by sulfuric and oxalic acid at 0.001M at all soil levels. EDTA was significantly efficient in the removal of Ni and Zn. The recovery of heavy metals, particularly Mn, decreased as the depth of sampling increased.   Heterogeneous bacteria and filamentous organism plate counts were conducted to evaluate the growth of the bacteria and filamentous organisms in the soil. Results showed that more organism growth took place in the bioremediated soil with a fertilizer added to it. The leaching of metals from the soil that was bioremediated in the pilot study was generally higher than the extraction of the metals from the soil that was leached with no bioremediation carried out. The results from this study suggest that the leaching of heavy metals from the contaminated soil is to a large extent dependant on the pH of the leaching solution. By increasing the soil's porosity and bioremediating the soil, higher extractions of metals were achieved.

Jun 1, 2010

By Elliott A, Kingsnorth D. J

The development of a large high grade spodumene orebody, in excess of 30M tonnes containing at least 7M tonnes at 4.0% Li20, by Lithium Australia Ltd at Greenbushes, Western Australia is significantly increasing the world consumption of lithium minerals. The availability of two low cost sources of lithium, spodumene concentrates (7.5% Li20) and glass grade spodumene (4.8% Li20) has been welcomed by the ceramic and glass industries as it assists them to lower their raw material costs at a time when they are facing severe competition from alternative materials. While there is no shortage of lithium reserves in the world, there has been a shortage of high quality lithium minerals. The Lithium Australia development has filled this need. The favourable factors of high grade, low impurities, open cut mining and existing infrastructure make this an ideal low cost source for a long term downstream lithium industry. The Lithium Australia mine development has filled the need for a reliable long term supply of lithium minerals. The long term viability of this resource is ensured by the unique combination of the following key attributes of the development : High grade reserves of 7.OM tonnes of 4.0% Li20 within 130 metres of the surface, contained within a total proven reserve of 30M tonnes of 2.8 % Li20. Open pit mining with stripping ratio of less than 2.5:1 waste:ore. Low impurities levels, particularly in those elements, that have a detrimental effect on the colour of glass/ceramics i.e. iron, manganese, titanium and chromium. An existing mine infrastructure that includes an adequate water supply for all foreseeable processing requirements. A sophisticated spodumene concentrator utilizing statistical process control to produce a consistently high grade product with minimal impurities. A technically qualified stable workforce fully acquainted with spodumene processing techniques. Greenbushes high grade concentrates have found ready acceptance in the specialty ceramic and glass industries during the past four years. The consistency and high grade/low impurity level of the product has enabled its use in the production of television tubes, oven to table ware, glass fibres, specialty glasses and ceramic glazes.

Jan 1, 1989

By McLennan T, Howells E, Zastawny H, Watt J. S

Nuclear techniques have been used to determine the solids weight fraction (W) and ash content of (fine) coal in slurries independent of voidage variations. The method is based on the correlation between W and the hydrogen concentration Hsl (wt/wt) of the slurry. Hsl is determined by combining measurements of neutron moderation and ?-ray transmission. Both Wand ash content are determined by combining the above measurements with the ash-sensitive measurement of X-ray backscatter compensated by a measurement of iron K X-ray intensity.The nuclear analysis system, called the SIRO coal slurry gauge, has been proved in a six-week plant trial at the BHP Steelworks washery at Newcastle, NSW. Several probes, each containing a radioisotope source and scintillation detector, were immersed directly into the coal slurry in the feed box upstream from the bank of flotation cells. For 140 samples W, ash and voidage varied in the ranges of 0 to 13 wt percent, 26 to 41 wt per cent and 0 to 4 vol. per cent, respectively. The r.m.s. difference in solids weight fraction, determined by probe measurements and conventional assay, was 0·52 wt per cent. Ash was determined with an r.m.s. difference of 2·0 wt percent in the coal. Better sampling techniques were used in the last half of the plant trial, and r.m.s. differences were 0.35 wt per cent solids and 1·5 wt per cent ash.

Jan 1, 1986

Laboratory electrical resistivity measurements of rocks are reviewed. Inductive and galvanic methods are discussed together with the ten important experimental factors which should be considered in an investigation.These experimental factors are electrodes, sample preparation, measurement errors, temporal current variations, current density, frequency, electrolyte composition, electrolyte saturation, pressure, and temperature.

Jan 1, 1969