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The attachment of a spherical particle to a bubble is theoretically investigated under the condition of a mixed sorption coating of a collector. It is shown that the attachment is determined primarily by the hydrodynamic factor involving the displacement of liquid from the gap between a bubble and a particle. The dependence of the attachment on the state of the surface of particle (sorption coating) is due to a change in the boundary conditions on the interface with water both in the case of surfactant chemical sorption and in that of the physical adsorption of oil. It is demonstrated that at large distances the thinning of a interlayer is facilitated by a physically sorbed collector, while near the bubble this is done by a chemically sorbed one.

Jan 1, 1993

By D Giurco

This paper presents the results from research undertaken in the CSIRO-funded Mineral Futures Collaboration Cluster on developing a future vision for the mining and minerals industry – Vision 2040 – in which the industry proactively contributes to long-term benefit for communities and the nation. Our research finds that Australia is currently experiencing mining-led prosperity due to high commodity prices, yet underlying this are challenges for maintaining market share due to lower productivity from extracting lower grade, more remote and complex ores. Whilst much focus has been on developing new technologies for finding and processing such ores, this paper assesses these activities, together with policy and market innovations in the context of needing to strengthen social, environmental and financial capital for long-term benefit. Vision 2010 sees mining activities linked to systems that are net providers of clean water, energy and ecosystem services, rather than minimising negative impacts alone; sovereign wealth funds are used to harness current prosperity for future innovation. Using a case study in lithium and comparisons to iron/steel, coal and copper – we illustrate the opportunities for new technology, policy and market innovations to link the mining and minerals sector in Australia to more sustainable patterns of production, consumption and prosperity.

Nov 22, 2011

By X Yang

White phosphorus (P4) is a critical element in industry, but its current production from phosphate rock using the carbothermal reduction method raises significant environmental and health concerns. This pressing issue necessitates the development of new technologies that facilitate the sustainable production of P4. In response, my team is actively developing an innovative, coke-free approach for white phosphorus production. This method involves the dissolution of phosphate rock in molten CaCl2, followed by the extraction of P4 through electrochemistry at relatively low temperatures. Moreover, this approach has the potential to utilise phosphate-bearing solid wastes as raw materials, further enhancing its environmental benefits. By employing this cutting-edge technique, we aim to revolutionise the phosphorus chemical industry towards greener and more sustainable practices. This paper provides evidence of the feasibility and effectiveness of our proposed approach.

Aug 21, 2024

The Filblast Cyanidation Process incorporating intense high shear mixing, high gas mass transfer efficiency and high oxygen concentrations under conditions of elevated pressure has now been been successfully applied in gold cyanidation mills since May 1993. The first commercial unit had a slurry capacity of 110 cubic metres per hour. Since then 230 and 450 cubic metre per hour units have been installed and a 1000 cubic metre per hour unit has been designed. Laboratory and pilot plant Filblasts have also been built.The reactor is a robust, compact in-line or end-of-line device and may be constructed out of a wide range of materials including wear and corrosion resistant alloys and ceramics. The Filblast Process may be applied to high temperature leaching of refractory gold ores and base metal concentrates.

Jan 1, 1997

Magneto flotation is a recently developed method aimed at simultaneous utilisation of the magnetic and flotation properties of minerals in separation processes. In this method, magnetic minerals are prevented from reporting to the froth product while non-magnetic minerals are being floated. With suitable ores, this makes it possible to reduce or entirely eliminate the cleaning and scavenging operations that are otherwise necessary in conventional flotation and magnetic separation systems. This paper describes the testing of magneto flotation on a Canadian magnetite ore. The ore sample used in the experimental work contained a total of 32.89 per cent Fe of which 87.60 per cent was magnetic in the form of magnetite. Magnetoflotation yielded, in a single step, a final concentrate assaying 69.10 per cent Fe and with an overall recovery of 84.84 per cent representing a magnetic iron recovery of 96.39 per cent. Comprehensive comparisons were made with conventional magnetic separation and flotation, and it was found that with these methods at least four processing steps were required to achieve results similar to those obtained with single-stage Magnetoflotation.

Jan 1, 1993

The development of paraprofessional courses in metallurgy and related disciplines, by the Department of Technical and Further Education in New South Wales, is outlined in this paper. The changing nature of metall- urgical educational requirements is summarised, and various attendance patterns discussed. The potential advantages of the sandwich system of College attendance, to the more distant sectors of the mineral processing and metallurgical industry is outlined. Some of the likely future trends in technician education are presented. These include the need to respond to the changing expectations of technician employers, as shown by industrial surveys, the role of experiential learning, the need to integrate courses so that students can build on prev- iously completed courses, the possibility that future technicians will require a multi- disciplinary background and the provision of easier access to technical college facilities by potential students and industries.

Jan 1, 1978

By W J. Bruckard, M J. Vaisey

Ashton Mining Ltd (Ashton) and Lynas Corporation Ltd (Lynas) have established a joint venture partnership to develop and process rare earth oxides (REOÆs) from the Mt Weld deposit in Western Australia. The deposit is located in a deeply weathered volcanic carbonatite structure that contains approximately two million tonnes of rare earth oxides at an average grade of 20 per cent REO. As part of the 1999/2000 feasibility study currently being undertaken by Ashton and Lynas, an extensive laboratory beneficiation test program was undertaken by CSIRO Minerals on diamond drill core samples from the Mt Weld orebody. The aim was to develop a flowsheet, based primarily on flotation that could be confirmed at pilot plant scale. The target concentrate grade was 52 per cent REO with a REO recovery of at least 35 per cent. Two main ore types, nominated as CZ (limonitic siltstone) and LI (nodular limonitic ironstone) were identified for separate laboratory evaluation. The lower grade LI-type ore overlies the higher grade and more extensive CZ-type ore. The majority of the work was conducted on the CZ ore; only limited testing of the LI ore was undertaken. The latter contains a clay component that will present difficulties in processing due to its poor filtering and settling characteristics. Two processing options for treatment of CZ ore were presented for pilot plant consideration. One (Option 1) includes gravity concentration prior to flotation while the other (Option 2) includes finer grinding and four stages of open circuit cleaning. The benefits of each scheme are discussed in detail. Neither has been fully optimised and the definitive flowsheet is most likely to be a hybrid of the two schemes, incorporating the best features of each. Typical metallurgical results from each scheme were final concentrate grades of 49 per cent REO, 10-16 per cent Fe2O3 and 3.2-4.8 per cent CaO. REO recoveries were above 35 per cent in both cases. Features of the processes developed by CSIRO were the inclusion of a gravity concentration stage prior to flotation, a modified flotation reagent scheme, a change in the method of feed preparation, and incorporation of magnetic separation to upgrade final flotation concentrates. Metallurgical results obtained from flotation tests on LI ore were much poorer than those obtained for CZ ore. The best rougher/scavenger result, with the limited amount of testing so far completed, was an REO grade of 32 per cent with a recovery of 28 per cent. Further work is needed to develop a viable processing route for this ore type.

Jan 1, 2000

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

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

Nov 24, 2014

By D Williams

Recent advances in global positioning systems (GPS), machine guidance technology and telemetry allow an unprecedented level of control of surface mining operations. GPS technology can now locate the bucket of a shovel or the blade of a dozer within 50 mm. Some of the outcomes possible are: precise selective mining û even when the ore is visually indistinguishable from waste; tracking grade and tonnage of every ore parcel through the mine; real time productivity monitoring; detailed post accident safety analysis; and tracking the movements of every piece of equipment. This paper will consider the contribution that GPS based machine control systems can make to ensuring that surface mining projects deliver the outcomes promised in the feasibility studies. Case studies of installations are presented.

Jan 1, 2003

By Mark C. J

Since the commissioning of the BHAS Copper Plant in 1984 the copper electrowinning operations have not fully met expectations. During 1988, a laboratory scale electrowinning unit was constructed to enable an investigation of the effects of process parameters on copper cathode deposition and quality. The process parameters investigated were copper concentration, acid concentration, current density, electrolyte temperature, electrolyte flow, electrolyte impurities and electrolyte additives. The findings of this research program indicate that there is an optimum cathode deposition morphology which results in good quality copper deposits which have improved stripping characteristics. All of the process variables investigated influenced the copper deposition and therefore it was necessary to delineate a suitable operating envelope for the copper electrowinning. As a result new standard operating parameters in electrowinning have been implemented which has enabled the production of higher quality copper cathodes with improved stripping characteristics.

Jan 1, 1989

By Y S. M Tabatabaei, R Hosseini Tabata

Application of Acidithiobacillus ferrooxidans bacteria to flotation of Sarcheshmeh low-grade copper sulfide ore was studied. Sarcheshmeh low-grade ore contains pyrite, which causes some problems in the flotation of copper minerals. In this study, A ferrooxidans was used to change the surface chemistry of pyrite and copper sulfide ores and consequently, their flotation behaviour. In the presence of A ferrooxidans and xanthate as a collector, pyrite was depressed whereas chalcopyrite and other sulfide minerals were unaffected. In addition, the pulp pH remained unchanged. It was shown that the surface chemical properties of the bacteria could be manipulated successfully to achieve the desired effects in a flotation process. The results showed that the recovery of pyrite in the presence of the bio-depressant is 50 per cent lower than when no bacteria were present. At the same time the recovery of chalcopyrite remained unchanged.

Jan 1, 2004

This paper reviews hydrometallurgical processing technology for refractory gold ores, which form an increasing resource stock for gold. The reasons fQr ore refractoriness and pressure, chemical and biooxidation process options are briefly listed. Electrochemical technology, suitable for processing refractory ore is reviewed and some preliminary results for the electrochemical oxidation of slurried arsenopyrite are given.

Jan 1, 1992

By Torrance AC

A joint research programme conducted by BHP Central Research Laboratories and Du Pont Wesfarmers Pty Ltd examined the effect of the size of cast primers on the run up and steady state detonation veloci- ties of ammonium nitrate based explosives as a function of blasthole diameter. Both continuous and point to point velocity of detonation meas- urement techniques were used. The field trials examined a number of the Du Pont HDP series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the run up velocity of 187mm diameter ANFO charges is negligible using cast primers as small as 150g. owever, emulsion and watergel explosives did exhibit run up in both 187 and 311mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blasthole diameters.

Jan 1, 1988

By B Tessier

Checking the quality of a blast may be considered as subjective. Checking this quality will require measuring objective parameters. One of them is the resulting fragmentation of the blasted product. Numerous fragmentation æmeasuringÆ systems have been developed and marketed, based on image-processing. This presentation of FragScan will illustrate advantages and difficulties when using such a system. FragScan is essentially defending a policy of large and representative sampling. The purpose is to show how fragmentation is discriminating both productivity and profit of quarry operations on a blast-by blast basis. The next step will then be to ædriveÆ the blasting process to reach a æbetterÆ fragmentation. Other applications require the fragmentation as an essential result: this is the case for large boulders used in structure-reinforcement. Several case-studies have shown that FragScan can be used for quality-control, checking size-distribution of the product according to the requirements of the end-user. Only clear thinking about the precise use of such a æmeasurementÆ will further the success of this task.

Jan 1, 2001

Every year my consultancy business reviews over 100 mines worldwide, primarily focusing on property and business interruption risk. What we have found is that the most successful mines have: identified their principal risks and determined what controls are required to manage or eliminate these risks; and managements systems that underpin these risks and the business in general.

Jan 1, 2003

Coal exports are forecast to grow strongly, so that coal is likely to remain very important to Australia for the foreseeable future. However there is no sign that prices or profitability will rise of their own accord. Therefore the intense squeeze on costs will continue for the foreseeable future. This will mean lower manning, more outsourcing and probably an increasing rate of company attrition. As well, the political pressure from the greenhouse debate is only going to intensify and the pressure on the Federal Government after Kyoto is likely to be irresistible.

Jan 1, 1998

By J, J M. Young, P T. Nielsen, R Zhu

Improved understanding of the variables that influence hydrocyclone performance is of increasing interest to the iron ore industry, where hydorcyclones are widely used to deslime fine ore. In many cases, the impact of particular variables is not quantified sufficiently well experimentally to ensure that industrial performance will match expectations. The current work focused on developing and implementing a systematic methodology to evaluate and compare the performance of four different hydrocyclones in a desliming application. A critical component of the project was the design and construction of a pilot-scale hydrocyclone rig using state of the art monitoring and sampling methods. A wide ranging test programme was conducted to quantify the effect on metallurgical performance of the key hydrocyclone variables such as pressure, feed density, vortex finder size, spigot size and hydrocyclone make/overall design. Details of the experimental approach are presented, along with a discussion of the sizing analysis methods used. Performance criteria were established to assess the four hydrocyclones. The effects of each major variable were quantified over a wide range of conditions. The results show that clear performance differentiation was achieved, enabling the selection of the optimum configuration. The results from this work demonstrate the benefit of objectively assessing the performance of nominally equivalent units in selecting an optimum configuration that best satisfies the performance criteria.

Jan 1, 2002

The following is a brief summary of the Bulli Colliery and its method of operation when Australian Iron and Steel Ltd. took control.Bulli Colliery is situated about a mile west of the village of Bulli and is some 10 mUes north of the Australian Iron and Steel Company's Steelworks at Port Kembla.The mine is owned by Australian Iron and Steel Limited, who purchased it in 1936 from the liquidators of Bulli Colliery and Coke Works.It is one of the oldest working coal mines in Australia, having been opened about 1858 and has worked more or less continuously since that date.The seam worked is the No. 1, or Bulli, Seam, which outcrops along the escarpment of the Illawarra Range and is generally operated by tunnels, the portal at Bulli being some 440ft. above sea level.The colliery holding is fairly extensive, but the coal seam over a large portion of the area within two miles of the outcrop has been more or less destroyed by an intrusion of basalt.At present there is no coal being worked within a distance of about 21 miles from the surface, the farthest workings being about four miles from the tunnel mouth.The existing main haulage road, for the first two miles from the portal, is not straight; it is very narrow over fairly long stretches and has many changes of grade varying from 3% in favour of the load to 13% against the load.The dumping station and screens are situated close to the portal of the haulage tunnel, and at this point the coal is loaded into railway hopper waggons, which are then hauled by rope to the top of a self-acting incline. The waggons are lowered down the incline, a distance of approximately! mile, the ruling grade being about 18 %.From the bottom of the incline, waggons are hauled by Company's steam locomotive to exchange sidings from whence they are taken by New South Wales Government Railway engine to the Company's Steelworks at Port Kembla.

Jan 1, 1947

Thank you for asking me to address you. The topic may sound formidable. Those of you with determination to go somewhere in your careers will understand that by taking geoscience, mining and metallurgy courses as students, you are declaring your intere

Jan 1, 1994

Seven papers included in Session 8 of the Third International Mine Water Congress under the heading "Achievements in Mine Water Management & Research" have been reviewed. Only one paper, a case study by Masters on biological treatment of inorganically polluted effluent, has any connection with research in the sense of seeking new, generally applicable knowledge which would advance the frontiers of mine water management. The remainder deal with various aspects of the management of mine water ranging from investigation of the geology of a specific aquifer system through operating dewatering systems to the management of specific effluent disposal problems.

Jan 1, 1988