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By H Aral, L Malishev

The carbothermic chlorination of titaniferous materials such as rutile, synthetic rutile (SR), upgraded slag and ilmenite in a fluidised bed is an established commercial process. In this work, ilmenite sourced from the Murray Basin area of South Eastern Australia was chlorinated and an assessment of the chlorination characteristics of the ilmenite, in terms of pre-treatment, type of reductant and reaction time was made. Selective chlorination of Murray Basin ilmenite to remove Fe and Mn was achieved in this work. A synthetic rutile sample containing around 93 per cent TiO2, one per cent Fe2O3 and 0.5 per cent MgO was produced at a chlorination temperature of 1000¦C with around 25 per cent loss of Ti as TiCl4. Raising the reductant to ilmenite ratio in the chlorination reactions increased the amount of Ti chlorinated. However, complete chlorination of Murray Basin ilmenite to produce FeCl3 and TiCl4, was not achieved under the conditions used in this work. Pre-oxidation of Murray Basin ilmenite before chlorination had little affect on its reactivity, compared with æas receivedÆ ilmenite. In contrast weathered West Coast ilmenite chlorinated appreciably better than West Coast primary ilmenite, in terms of bed residues remaining and amounts of elements removed. The presence of large amounts of Mg and chrome spinel grains in the Murray Basin ilmenite used in this study are likely to make it difficult to chlorinate directly in a commercial chlorinator. However, this is not to say these ilmenites will be unsuitable for chlorination applications. Further work is needed in the separation of Mg and chrome spinel grains from Murray Basin ilmenites and the products resulting from these tests could then be assessed in terms of chlorination performance, so that further processing options can be explored.

Jan 1, 2000

By Z Li, Z Yan, M Yang

Recycled cement paste (RCP) is a kind of CaO-rich recourse, which is separated and recycled from waste concrete. Due to its chemical composition, RCP could partially replace lime as a flux and be loaded into electric arc furnace (EAF) steelmaking process. Rapid RCP assimilation and liquid slag formation have significant effects on EAF steelmaking process. In this study, the dissolution behaviours of RCP and lime at temperatures of 1400°C to 1500°C were investigated using static dissolution experiment. The dissolution rate, interfacial microstructure, as well as dissolution mechanisms were discussed. It was found that the dissolution rate of RCP was much higher than that of lime. RCP could be completely dissolved into slag in 60 secs at 1500°C. The dissolution rate of lime was in range of 3.910-4 g/(cm2ꞏs) to 2.610-3 g/(cm2ꞏs), while that for RCP was in range of 1.510-3 g/(cm2ꞏs) to 4.910-3 g/(cm2ꞏs). As for lime dissolution, a dense layer of dicalcium silicate (C2S) generated at the dissolution interface, and the diffusion of Ca2+ in C2S layer was the limited step for lime dissolution. Some of calcium ferrite could be observed at the interface between lime and C2S layer. As for the RCP dissolution, there is no obvious product layer of C2S formed at the dissolution interface, Fe2+ continuously diffused into RCP layer during the dissolution, and small amount of FeOꞏMgO solid solution generated and gathered at the dissolution interface. The dissolution rate of RCP in EAF slag was quite higher than that of lime, partially add RCP as flux in EAF could accelerate the slag formation process.

Aug 21, 2024

In this year marking the centennial of the Geological survey of Western Australia, it is appropriate that we should review the value of the contribution of the Survey, and Australian Geological Surveys in general, to the exploration industry. Most geological surveys in Europe and North America had their origins in the first half of the 19th Century when the burgeoning Industrial Revolution was demanding the identification of new sources of coal and iron ore. Australia, as a young nation, essentially dependent on an agricultural and pastoral industry, and with already discovered vast coal resources in Eastern Australia, had, no great need to explore for new mineral resources. However, with the discovery of gold in 1851, the mineral potential of the country became apparent to the whole world and the first Geological Survey in Australia was set up in 1852 in Victoria under A.R.C. Selwyn. After a number of false starts all Australian States had an established Geological Survey by 1900. It is hard to assess the contemporary value of the early work of the Geological Surveys with respect to exploration, almost all major mineral discoveries were made by prospectors and most mining companies had little time for geologists - although the Chamber of Mines in Western Australia in 1910, did recommend that the Geological survey be granted an additional ten thousand pounds over two years to map all existing goldfields and the country between them, and produce a reconnaissance map of the area east of a line between Wiluna and Edjudina as far as the South Australian border!

Jan 1, 1988

By J Mavrogenes, C J. Spandler, S M. Eggins, K Worden

Major occurrences of platinum group minerals (PGM) are in crustally-contaminated, huge, layered igneous complexes (Bushveld and Stillwater) and gabbroic intrusions (Norilsk); relatively minor occurrences include arc-related æzoned Alaskan ultramaficsÆ. In terms of arc-related provenances, the recognition of alluvial PGM in river and beach deposits of southern South Island (Mitchell, 1995), in situ in the Longwoods (Cowden et al, 1990), and the ultramafic-mafic layered Greenhills Complex at Bluff (Spandler et al, 2000) raise the possibility that some economically-significant PGM deposits may exist in New Zealand. The Longwoods and Greenhills are in the Brook Street Terrane which is a remnant of a primitive intra-oceanic arc system of Late Permian-Early Triassic age. The Terrane comprises volcanogenic sequences containing plagioclase- and clinopyroxenephyric basalts, high-MgO ankaramite and dolerite dikes, trondhjemite plutons, and basaltic to andesitic volcaniclastic and sedimentary rocks. The cumulate complexes contain early-formed olivine- and clinopyroxene-rich ultramafic cumulates overlain by anorthite and hornblende-bearing gabbros. Primary (isoferroplatinum) and secondary (sperrylite) platinum group minerals are preserved in chrome-rich spinel pods in basal dunite of the Greenhills Complex. Saturation during early fractionation of primitive high-MgO magmas rather than magma mixing seems likely for the primary PGM. Together with correlative terranes in Queensland and New Caledonia, the Brooks Street Terrane is an exposed cross-section of an extensive Permo-Triassic island-arc system. Most parental magmas were primitive island-arc tholeiites, but other primary magma-types include high-MgO ankaramites and trondhjemites û the latter formed by partial melting of lower crustal clinopyroxene-rich cumulates and gabbros, respectively. The parental ankaramites fractionated to form mafic-ultramafic cumulates and primitive to evolved melts of high-Al basalt to andesite compositions (Takitimus). The Brook Street Terrane is an analogue for modern intra-oceanic islandarc systems and allows detailed study of subvolcanic arc processes.

Jan 1, 2005

By Y Xu, J Hacker, D J. Williams

Shear strength parameters of compacted clay liners are needed to analyse the stability of mine waste dumps containing compacted clay liners as sealing layers for potentially acid forming waste rock. A representative clay sample was supplied by McArthur River Mine from the mine site in the Northern Territory, Australia, with an average as-supplied gravimetric moisture content of about 13.6%. The clay was compacted in a 100 mm by 100 mm direct shear box at the as-supplied moisture content to a dry density of 1.85 t/m3, representing the field compaction specification adopted by the mine. To determine the peak and ultimate shear strengths of the compacted clay, single-stage direct shear testing was carried out at nominal initial normal stresses of 50 kPa, 100 kPa and 200 kPa, representing shallow depths of burial in the North Overburden Emplacement Facility of about 2.8 m, 5.6 m and 11.1 m, respectively (assuming a waste rock wet unit weight of 18 kN/m3). Three shearing rates of 1 mm/min (rapid), 0.1 mm/min (intermediate) and 0.01 mm/min (slow) were applied to study the influence of shearing rate on shear strength. In addition, the development of a residual shear plane was tested by reversal and re-shearing in the direct shear box. In the first shearing, the peak and ultimate shear strengths are determined. The normal load was then removed and the box rewound to its starting position. The normal load was then re-applied and the specimen re-sheared. Two reversals were applied to each specimen, and it was found that there was no significant reduction in shear strength. Finally, based on a range of shear strengths obtained in the laboratory for McArthur River Mine clay and other materials by various laboratories over time, shear strength parameters for the compacted clay were recommended for use by the mine.CITATION:Xu, Y, Williams, D J and Hacker, J, 2018. Shear strength of compacted clay liner at McArthur River Mine, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 208–219 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By S M. W Rajaratnam, P Varma, T L. Sletten

Mining employees undertaking shift work are at considerable risk of experiencing sleep disturbances and circadian rhythm disruptions. In the complex, high-risk environment of mining, these sleep and circadian disruptions lead to adverse impacts on employee health, alertness and safety. Evidence-based tools that effectively target improvements in sleep health amongst shift workers are needed. Variability in work hours and individual differences in the response to shift work mean that a ‘one-size-fits-all’ solution is often insufficient in complex work environments. Currently no interventions provide tailored support for shift workers based on their rosters, personal commitments and sleep habits. Existing technologies, such as smartphone applications and watches, allow sleep monitoring, but their strategies are targeted towards night sleepers, which does not translate to shift work contexts. To address this, our team has developed an innovative digital tool that implements biomathematical models to provide automated, personalised sleep and circadian intervention strategies to optimise sleep, alertness and performance during shift work. The tool uses mathematical models of sleep and alertness regulation that provide physiologically optimal times for an individual to sleep when experiencing circadian disruption. This program of work included co-designed development of a world-first app with shift workers and the examination of the preliminary efficacy of the intervention for improving sleep, alertness and performance.

Apr 16, 2024

Design of cemented fill in mining is often carried out without any consideration of the structure of the fill. The composition of cemented fills varies in the stopes due to the placement method, and the strength of the fill in the laboratory depends on the density, orient- ation, moisture content and drainage conditions. Within each stope there are definite zones and the structure of both cemented rockfill and cemented hydraulic fill has to be defined for each zone and the field conditions simulated in the laboratory. Structure also affects fill permeability and compressibility. From a study of the cemented fill in place, the effect of changes in the placement methods can be seen and then controlled to improve fill performance and economy. These features of cemented hydraulic fill and cemented rockfill behaviour are discus- sed and illustrated through reference to field and laboratory work undertaken at Mount Isa.

Jan 1, 1973

By R Robinson

Modem occupational health practice can be described as the fitting of work to the individual and each individual to his job; perhaps a non-traditional way to view occupational health. This two-component description is achieved through the development of programs to implement and monitor specific job procedures, from the monitoring of unwanted exposures to contaminants to the auditing of mine sites. This paper is about such programs. Some attempt must be made to evaluate the effectiveness of the program and several performance indicators which are intended to measure the effectiveness of such a program are offered.

Jan 1, 1994

By Abdulhadi H. M, Soliman S. A

The Western Desert of Egypt is a part of the arid Great Sahara of Africa which extends from the Nile Valley in the east to the Atlantic Ocean in the west. It is covered by a sedimentary sequence of Mezozoic and Teriary rocks. Recently this part of the country (about 65% of its surface area) has attracted an increasing attention in the plan of finding new agricultural and industrial communities outside the crowded Nile Valley. The plan aims to reduce the high population density in the narrow Nile Valley and to cover a considerable part of the increasing food demands in the country of Egypt. Accordingly, the groundwater exploration work in the Western Desert has been remarkably increased in the last decade, however it is still limited compared with the vast area of the Desert. The present work is a part of the groundwater exploration in the 6th October City, a new community located at 40kms west of Cairo. The rock exposures belong to a sedimentary stratigraphic section starting from the Cretaceous in the east to the Pliocene in the west. The Cretaceous outcrops due east are attributed to an almost N-S uplift and forms a thick massive limestone plateau which separates the present area from the Nile Valley. The Teriary section in the west have alternations of different porous formations such as the sands and sandstones which may acquire a good potentiality of groundwater resources. The previous groundwater exploration work included combined geological and geophysical investigations followed by exploration drilling. Although the area lies directly to the west of the Nile Valley, the discovered groundwater is saline and located at deeper reserviores compared with the groundwater in the Nile Valley. This groundwater was described as marine fossile water by the oil companies working in the Western Desert. From the geological point of view, it is believed that the Cretacious massive limestone plateau, in the east, roots to a depth which far exceeds the groundwater levels in the Nile Valley and acts as an impervious barrier between the aquifers in the Nile Valley and the area under investigations.

Jan 1, 1988

By A K. Ghosh

"Inrush of water is always an issue, especially for mines located in heavy rainfall areas. Nowadays, mining companies and research institutes have developed many advanced technologies for study and analysis of hydrological processes. In this paper, an advanced method is introduced, which uses the Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data in the Geographical Information System (GIS) platform to simulate the stream distributions around two specific mines: Super Pit and Griffin coalmine in Western Australia. The impact of this approach is important because it reduces the time and economic cost by creating a high spatial resolution hydrological map in the specific areas. The study identifies the flow path of the run-off water, which helps in adopting a suitable water management plan surrounding the case study mines. The results match with the ground reality. Based on the results, the stream structure around Griffin coalmine is more complicated than that of Super Pit. The bifurcation ratio and drainage density are computed to estimate the subsoil permeability characteristics of the two mines. Recommendations have been put forward to prevent and reduce the potential risks of water accumulation around the open pit mines.Citation:Ghosh, A K, 2016. Application of Shuttle Radar Topography Mission Data in Hydrological Analyses of Super Pit and Griffin Coal Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 162–169 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By Medhurst TP, Trueman R

The aim of the paper was to model numerically some aspects of the extraction of coal pillars by split and fendering. A two-dimensional elasto-plastic plane strain model with strain softening and interface mod- elling was used. The model was able to simulate the improvement of conditions experienced in lifting from the fender, when the roof adjacent to the fender has caved. In contrast, when a stook was left, providing support to a span of uncaved roof, the model pre- dicted the fender would suffer considerably more de- formation and strain.

Jan 1, 1992

The paper describes the reasons for developing, specifically in South Africa, dense medium processes to allow baths to operate at low (about 1,35) and high (about 2,0) cut points. Low density processing was developed to meet the demand for low ash coals; high density processing was developed to enable heavily contaminated raw coals, destined to be burned in captive power stations, to be de-shaled without loss of combustibles. The anticipated and actual technical difficulties of operating baths at such density extremes are described, and the results from operating plants outlined.

Jan 1, 1987

By W G. Rowley

The Fortescue Metals Group story began in 2003 with a vision to establish an infrastructure project that would connect the stranded iron ore deposits of the Pilbara region of Western Australia with the steel mills of Asia. Following exploration successes in the Chichester Ranges using their new exploration model, Fortescue established significant iron ore resources at Cloudbreak and Christmas Creek during 2004 and 2005. By May 2006 the definitive feasibility study for mine, rail and port was completed, many of the key government approvals had been obtained, product development and market acceptance were complete and 1.07 Bt of total proved plus probable iron ore reserves were defined to support a 20 year mine life from the Cloudbreak and Christmas Creek deposits. Project construction commenced in September 2006 following a successful $3.2 billion capital raising. By April 2008, the mine and processing plant at Cloudbreak were completed along with the Herb Elliott port facility at Port Hedland and 256 km of heavy haul railroad linking the mine with the port. Mining of overburden commenced at Cloudbreak in late 2007 and by 15 May 2008 the first shipment of iron ore had departed for China. In the first 12 months of operation total shipments amounted to 24.6 M wet metric tonnes with weighted mean composition of 58.9 per cent Fe (64.4 per cent Fe calcined), 4.3 per cent SiO2, 2.0 per cent Al2O3 and 0.047 per cent P. Exactly 3.5 years between the Cloudbreak discovery hole and commercial production. The project success depended on many technical breakthroughs including a new exploration model, application of the surface miner as the main mining production unit, design of a new marketable fines product called æRocket FinesÆ, a highly efficient ædesandÆ flow sheet for upgrading of 2.4 per cent alumina run-of-mine to 1.9 per cent alumina Rocket Fines, 40 t axle loads for the heavy haul railway and a high capacity-highly automated port facility.

Jan 1, 2009

By R S. Sing, M D. Yadav, G Udaybhanu

This paper presents the results of the first part of a research project to study the effect of various inhibitors to reduce the spontaneous heating susceptibility of some highly susceptible Indian coal seams. In this investigation 11 inhibitors were chosen and applied at three, five and ten per cent of their concentrations in an aqueous solution for four coal samples collected from four different seams. The susceptibility of coal samples, before and after application of these inhibitors, was determined by carrying out crossing point temperature (CPT) analysis. The findings of this study have indicated that it is possible to retard the tendency of spontaneous heating of Indian coals to a considerable extent by the application of six of the inhibitors studied. Further, these inhibitors were tested in 1:1 combination to study their synergistic effect. Finally the economics of the application of these inhibitors has been analysed and four inhibitors are recommended for field use. These results have direct application to control fire and improve productivity and safety in coal mines.

Jan 1, 2005

By D Bradshaw, E Forbes, M Edraki, M Tayebi-Khorami, E Manlapig

There is an increasing trend in the extraction and development of copper resources from complex deposits. These deposits pose mineral processing challenges, as they often contain low grade disseminated copper ore with high levels of impurities particularly arsenic. Although arsenic is a naturally occurring element, the concentrations of arsenic can be magnified by mining and mineral processing activities. Therefore, while arsenic has no significant market value, its presence in the ore deposit will have production, environmental and human health implications. The mining industry’s approach to life-of-mine planning has improved significantly in recent decades and managing arsenic is not an exception.CITATION:Tayebi-Khorami, M, Edraki, M, Manlapig, E, Forbes, E and Bradshaw, D, 2018. Arsenic pathways in copper mining – sustainability issues and potential solutions, in Proceedings Life-of-Mine 2018, pp 60–63 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By A J. Burchell

The introduction reviews the tunnelling carried out in Singapore since the early 1980s. Between 1983 and 1990, Phases 1 and 2 of the mass rapid transit system were constructed. These included some 20 km of bored and cut and cover tunnels together with 18 underground stations. Some particular points of interest in this massive project are briefly commented upon. Reference is also made to other underground or underwater schemes undertaken during this period such as the proposed large caverns project and the submerged tunnel to Pulau Seraya. A description of the subsurface works, now under construction in Singapore, follows. This includes an all underground North-East railway line 20 km long with 16 stations. At a budget of US$ 3 billion, this is a major civil engineering undertaking. Another project is the extension of the railway to Changi Airport which involves 3.5 km of twin tube tunnelling together with a major underground station which is fully integrated into the airport terminals. An on-going program of further major railway extensions over the next 10 to 15 years is in place and an outline is given of some of the most important underground sectors. Other proposed projects such as the underground roads system and the deep level sewers are briefly described. Together they demonstrate the very significant volume of underground construction scheduled for the next century in Singapore.

Jan 1, 1999

The Electrolytic Refining and Smelting Company of Australia Limited (ER&S) operates a copper smelting and refining plant and is situated close to the heart of the highly industrialised area of Port Kembla. In March, 1982 the Company entered into an undertaking with the State Pollution Control Commission (SPCC) to monitor ambient levels of sulphur dioxide (S02) gases present in the atmosphere in the surrounding urban area. Despite the use of a 200 metre high stack for dispersal of the smelter waste gas stream at ER&S, two local suburbs, Warrawong and Primbee were experiencing on occasions high ambient concentrations of S02 resulting in discomfort to local residents. In late March 1982, ER&S installed a highly advanced S02 monitoring system to continuously monitor the levels at Warrawong. The system was extended to include S02 monitoring at Primbee in November 1982, and further extended in June 1983, to include an input of meteorological data. Initially the system was designed to monitor and react to high concentrations of S02 at either of the two monitoring stations. Currently however, refinement is taking place to allow a predictive nature to be built into the system such that it not only reacts to an adverse situation but can predict weather patterns likely to cause high concentrations and thus avoid these events. The entire system is still undergoing a growth and development period, however the results obtained to date are pleasing to both the Company and the SPCC.

Jan 1, 1984

By G R. Hancock, M J. Saynor, J B. C Lowry, T J. Coulthard

Landform evolution models (LEMs) can assess the effectiveness of landform designs applied to a rehabilitated landform by predicting where erosion may occur. Here, we compare erosion predictions produced by the CAESAR-Lisflood LEM with field observations from the rehabilitated Pit 1 landform of the Ranger uranium mine, based in the Northern Territory, Australia (Figure 1). The ability to predict long-term erosion at a catchment scale is important, as the final rehabilitated Ranger landform is required to physically isolate buried tailings material for at least 10 000 years. CAESAR-Lisflood has been extensively tested and calibrated using data collected from erosion plots (0.09 ha) on the Ranger trial landform (TLF) for multiple years (Lowry et al, 2020; Saynor, Lowry and Boyden, 2019). However, until recently, it was impossible to compare model predictions with field observations for areas larger than the TLF erosion plots. We can now compare model predictions of Life of Mine Conference 2023 | Brisbane, Australia | 2–4 August 2023 116 gully development with field observations from the newly rehabilitated, 40 ha surface of Pit 1 over two contiguous one-year periods: 2020–2021 and 2021–2022. The aim of this study was to assess whether the CAESAR-Lisflood model can successfully predict gully erosion at a larger spatial scale.

Aug 2, 2023

By H Hy÷tyniemi

In this paper multivariate data analysis performed on a new multi-camera system implemented to zinc flotation circuit of PyhSsalmi mine is presented. Image-analysis-based system was developed to take advantage of the commonly known fact that the changes in the flotation process are reflected to the visual appearance of the froth surface. Most often the changes are seen first in the froth and later in other process measurements. The image variables are already utilised in closed loop control and considerable savings are achieved with the current setting, but the results coming from the separate cells are used individually. This is clearly not the optimal way to take advantage of the many measurements coming from different locations of the process. A better approach would be for example to use the measurements coming from the early stages of the process to predict the behaviour (or improve the quality of measurements) in the later stages. The methods described in this paper are aimed to improving the situation in this sense.

Jan 1, 2005

The Research Centres Program initiated by the Federal Government and supported by the mining industry has had a major impact on geoscience research and education during the past five years. Eight major university based-Geoscience Research Centres are currently supported by the Government, including four Key Centres of Teaching and Research and a further four Cooperative Research Centres (CRCs). The Research Centres Program has led to a concentration of high quality research and teaching in areas of demand and strategic importance creating strong university - industry linkages and a source of well trained and motivated graduates. Over the last decade Australia's reputation as a leader in mineral exploration and ore deposit research has grown substantially, in part because of the development of the Research Centres Program, and to increased collaboration and interaction between research groups and exploration geoscientists across the industry. During a period when ore deposit research activity has been decreasing in other countries (eg USA, Canada, Japan and most European countries), equivalent research activities in Australia have been increasing, within a well co-ordinated national framework. The future challenge for universities and the mining industry will be to maintain the momentum of the successful research centres in order for the centres to become self-funding over a six- to nine-year period.

Jan 1, 1996