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By J Johansson, E Lund, J Lööw, A Pekkari

Technological development is accelerating in the mining industry (Abrahamsson and Johansson, 2021) and in large parts of the world there is an increased environmental awareness (United Nations, 2015). This can mean both challenges and opportunities. The mining industry has long been criticized for its adverse environmental effects. However, there is now a lively discourse about the role of mining in facilitating the green transition towards sustainable development. Mining is increasingly recognised as a prerequisite for the green transition, by supplying key raw materials to enable, for example, digitisation and batteries for electric vehicles. The green transition not only amplifies the demand for metals and minerals but also intensifies pressure on the mining sector to assume greater responsibility for environmental and societal welfare (Dehaine et al, 2020). New technology, such as digitisation, automation, and remote control, play a crucial role in advancing towards more sustainable mining practices. Despite the expanding role of advanced technology, human involvement will remain important in the extraction process (Rogers et al, 2019), but new technology will change how miners do their work, which in turn will lead to changed competence requirements for miners (Herbert and Hidalgo, 2021) and increased need for further education. Given the significant shift towards sustainable mining, it is important to study how these changes may affect the work, competences, further education and skills of miners as human expertise will continue to be critical in the extraction process. Consequently, there is a need for proactive research to prepare for the inevitable changes and implement measures to support miners through this changeable period to ensure a smooth transition that protects miners’ safety and working environment. This extended abstract explores how new technology will affect the need for further education of miners in the future.

Sep 1, 2024

By C J. Stanley

Reflected light optical microscopy, or epimicroscopy, is one of the oldest techniques of modern mineralogy. At a relatively low capital cost, it is also very resourceful, and the analytical choice for the identification of most ore minerals. In ore mineralogy, reflected light optical images have the potential to overcome the main limitation of backscattered electron images from scanning electron microscopes, namely contrast of mean atomic number  below the spectral resolution of the backscattered electrons detector. This is the case for relevant ores, like iron (haematite-magnetite) and copper-zinc ores (sphalerite-bornite), but for both cases the pairs of minerals are easily discriminated in reflected light. The improvements in optics and electronics also made microscopy a powerful source of digital images, suitable for automated analysis for minerals processing, as the determination of liberation spectra. The drawback, however, has always been the impossibility to recognise the transparent minerals, which account for most of the gangue phases in ores, from the embedding resin, usually epoxy. In order to determine if there was any possibility to separate quartz from epoxy resins, reflectance spectra have been acquired for quartz and some commercial epoxy resins (Araldite, BuehlerÆs Epothin and Epocolor, Araldite spiked with fluorochrome from Struers), from 380 to 720 nm in 5 nm intervals. Reflectance of quartz and epoxy is very similar over the whole visible light range, and varies from 4.5 to five per cent. Epocolor, a red-dyed epoxy, reflects slightly more above 560 nm, as does Araldite spiked with the fluorochrome from 460 to 570, but for both the reflectance is still very close to that of quartz, under 5.1 per cent. This data set is final, and precludes the application of reflectance in light optical image analysis for assessment of liberation, phase quantification, or any other signal that requires separation of resin from transparent minerals.

Jan 1, 2008

A significant resource of uranium has been discovered within a buried palaeochannel located in the south western corner of the Officer Basin of Western Australia by PNC Exploration (Australia) Pty. Ltd. The mineral- isation is redox controlled and is hosted by Eocene organic rich paludal sediments. Prob- able insitu reserves are 13,000 t of contained uranium with an average ore grade of 0.12% at a cutoff grade of 0.03% U. The Mulga Rock palaeochannel has been traced for at least 100 km beneath the Quaternary surficial cover. The main channel is horseshoe shaped with the channel arms vary- ing from 5 to 15 km in width. The western arm connects to the Lake Raeside-Ponton Creek drainage system, whilst the eastern arm'is open to the south. The headwaters of the palaeo- channel are thought to have been the Lake Minigwal drainage system, prior to its capture by the Lake Rason system. Differential.erosion of the basement rocks during the Late Cretac- eous to Early Tertiary strongly influenced channel shape and resulted in the main channel being confined to a Permian,mudstone filled valley. Upwards of 100 m of fluviatile sediments accumulated within the palaeovalley during a period of subsidence in the Early Tertiary. Three broad stratigraphic units have been re- cognised within the channel: 1. An upper unit of fluviatile sands with interbedded lacustrine sediments, which have subsequently been wholly oxidised and variably silicified and ferruginised. 2. A middle unit of lacustrine to paludal sediments, which host the main mineral- isation. 3. A basal unit of fluviatile gravels and sand. The presence of excellently preserved Nothofagidites in organic rich paludal sediments from the middle unit, suggest that unit was laid down in a non-marine, fluviatile, humid environ- ment during the Middle Eocene.

Jan 1, 1988

By Toffeg A. N, Abdul-Hameed I

More than 1000 Ian of seismic reflection data correlated to ten exploration wells along with geological, gravity and magnetic data are used to construct the subsurface structure, in particular the crystalline basement, along a corridor approximately 100 Ian wide that traverses central Iraq in SE-NW direction for a distance of about 500 km from Baghdad in the central part of Iraq to Dohuk near the Turkish border. This transect is one of few such transects that represents the Iraqi contribution to the Global Geoscience Transects (GGT) project. The transect crosses two out of three major tectonic elements of Iraq: the unfolded zone and the folded zone.

Jan 1, 1990

A universal grinding circuit model suitable for an arbitrary structure of flowsheet has been suggested. In this model classifiers and mills are described in a most general form. What puts the model in a class by itself is the automatic mass balancing in all streams of the circuit. In order to provide this a special classifier model is adopted. A previously published continuous steady state process model is used as a grinding model. Non-linearity of classifier model leads to a resultant circuit model which is equivalent to a non-linear integral equation. It complicates somewhat calculation algorithm in comparison to that of linear model, but provides a physically meaningful solution.

Jan 1, 1993

In-seam drilling is conducted mainly to drain coal of gas and/or water prior to development or extraction. The requirements of inseam drilling for gas drainage have mainly surpassed the technical limits of rotary drilling and are mainly being addressed by guided down hole motor drilling, albeit at a higher cost. There is an increasing application of in-seam drilling to detect geological structures or other hazards or their absence in advance of mining to reduce the risks of underground mining. Close collaboration between miners, drillers, geologists, researchers and suppliers over the last four years has seen many advances made to improve the accuracy and reliability of inseam drilling. With such developments will come closer control over the ventilation and safety of future mining under deep gassy conditions, but not without costs. The paper summarises the current applications of inseam drilling, recent technological advances and the next generation survey and geophysical sensing tools which are currently being developed

Jan 1, 1998

The energy crisis and the general increase in fuel prices have changed the position of coal in the world. Countries need to review their policies on coal, depending on available reserves and their accessibility. On the demand side, a distinction should be made between the steel industry's specific demand for coking coal and the needs of power stations where coal is used in competition with other sources of energy. Coal consumption in these two sectors is expected to increase considerably over the foreseable future. Some countries have sufficient coal of their own to meet this increased demand but others will have to rely on imports. As a result, the tonnage of coal transported by sea may double by 1985. The coal industry lacks flexibility. The opening of new mines and the construction of a transport system to ship the coal takes time. This time-lag, coupled with the enormous expenditure involved, makes long-term contracts between producers and consumers essential.

Jan 1, 1975

Owing to the 'creeps' and consequent movements in the mines, followed by the recent fire in the southern workings, the whole of the orebody above the 800 ft. level is now very much crushed and broken. The same applies to the hanging wall or overwall coutrny, which has subsided towards the workings, so that for some years past all development work within the lode has had to be carried out with extreme care.The continual but slow subsidence of the overburden into the stopes necessitates a periodical renewal of all gangways in the lode, and, as the subsidence amounts to as much as 60 ft. in places, these new gangways must necessarily pass through the mullock-filling of old stopes in addition to broken ore. They at times pass into the broken ground of the hanging-wall for some distance, where the orebody has widened underneath by the original folding and puckering.

Jan 1, 1932

Investment decisions in the Australian mining industry are often made without awareness of the impact of risk on project outcomes. A fundamental change in thinking is required to move away from the traditional attitude of æcushioning the blowÆ towards a measured approach to project risk. Such an approach involves quantifying and understanding project uncertainty so that investments may be shielded from downside risk while at the same time exposed to upside potential. Communication and collaboration between study teams and corporate financial managers must be improved before the industry can improve its project investment record. Monte-Carlo simulation provides a way to quantify and understand investment risk, but its accuracy depends on how well the variability of input parameters is estimated. Research in this area is currently centred on quantifying uncertainty in mineral resource estimation using new conditional simulation techniques, but a less-rigorous method can be applied in practice to begin the education process and develop the required awareness at board level.

Jan 1, 2003

By Pollard D. M

The removal of nickel from lead by sulfur drossing was investigated using a technique which models industrial batch decoppering practice. Successful denickeling to 0.005% (Ni)pb was consistently obtained in the absence of silver, well below the experimental equilibrium value of 0.015% but still above levels obtained in industrial practice. Silver appeared to have little effect upon denickeling. The final nickel content was dependent upon the initial nickel content, the total sulfur addition and the stirring time. The presence of nickel was found to give no assistance to successful decoppering. Simul- taneous removal of nickel and copper was observed at silver contents in excess of 0.02%. Extended stirring resulted in a further lowering of the nickel content but reversion of copper to the bullion was observed. Experimental work has shown that nickel can be removed by a standard decoppering operation; a procedure which is used in secondary lead re- fining. Alternatively nickel can be removed during initial decoppering in primary lead re- fining operations.

Jan 1, 1987

By Doyle J

The direct method of gas content determin ation developed by McCulloch and Diamond of the U.S.B.M. has been adapted to estimate the gas content of coal seams from slim exploration borecores in the Southern Coalfield. Emphasis has been placed on the measurement of this parameter without the physical destruction of the core which is required for subsequent chemical analysis. In field and laboratory equipment is simple and inexpensive. It enables the determination of lost and desorbed gas from a fresh geological core. Residual gas is not measured but is considered to be relatively low and of no consequence in ventilation considerations. Results to date show good correlation with those obtained from underground face samples. Gas contents from the mined seams varying from 2 m3/tonne to 14 m3/tonne have been measur- ed with this apparatus. Gas desorption characteristics of South Coast coals have been found to closely follow exponential mathematical Models.

Jan 1, 1983

In attempting to vegetate pnob!em sites some basic pn.i,ne%ptes, namely the phys.ica.e and chemi.ca2 pnope/ti;es og the problem mateni.al and the selection oU hu.itab.2e p!antts {cor pnopagati.on, have to be considered. Pnobtem sites such as tai ing dams, mined-out atteas, and areas which have been genehaUy advehse2y a46eeted by mining activities, are not only o~ten located in a divehs.ity o4 climatic regions, but they also usuaUy dL64en substantially in theAjt .int' Lns c phys.ica2 and chem.i cat pnopen t i.es . To estabP.ish vegetation on such sites 6requent2y requites: .%) The ame Lonaton oU adverse {yaetors in onde t to exeate a hoot env.utonment suitable Uon "satis1actony" plant growth. .%i) These.2eationo4 plant species suited to the improved Hoot env.utonment, and eompat%b&e with the e2imate o{y the site, and the ultimate Land use o4 the site. iii) The estabL shment o{y a Laboratory and p-LLot scale testing programme to aeeomptizh the above.

Jan 1, 1976

By B Ascott, J Kennedy, A White

At mines with low tonnes per vertical metre, like the Jundee Mine in Western Australia, operated by Newmont Asia Pacific, high development rates across multiple mining areas are critical to achieving the delivery outlined, or promised, in the annual business plan. The challenge is to deliver the short-term requirements while keeping in balance with the long-term strategic direction. Newmont Jundee has developed a system called æMine Planning by QuartersÆ that integrates the planning process with the business process in one end-to-end continuum. Short-, medium- and long-term schedules are reviewed and updated by applying four integrated subprocesses, which capture new information as it becomes available. The four subprocesses are: resource development planning û evaluating mineral resource,reserve development planning û preliminary design for new reserves,mine operating planning û final mine design for reserves, andmine production planning û detailed plans for stoping a proved reserve. Commercial mine planning software is used in these subprocesses to facilitate the flow of information into a central storage æhubÆ for uploading into the rolling business plan. A regular and consistent quarterly review helps to identify and qualify areas of business risk at an early stage, allowing time to plan for contingency and minimise the impact of the risk.

Jan 1, 2008

In an industry that is data-hungry and increasingly international in its outlook, the role of the New Zealand Government in facilitating exploration and mining activity here presents unique challenges. All things being equal, the Regime itself should result in æefficient outcomesÆ, however central to this rational economic tenet are the assumptions that the regime is in keeping with the times, other legislation works in tandem with it, and that those who administer the regime have the knowledge and experience to apply the rules wisely. Following the Crown Minerals review in late 2003, a shift in emphasis from Crown Minerals æmanaging the ActÆ towards proactively æmanaging the mineral estateÆ for greater benefit for all New Zealanders means that these assumptions are being increasingly challenged and addressed through a variety of initiatives. These include improved access to relevant data sets, minimisation of red tape and compliance costs, increasing emphasis on permit holder compliance with work programme obligations, changes to the Minerals Programme and regulations, closer collaboration with and representation to other government departments and councils, and additional recruitment of industry-experienced staff. This presentation will highlight aspects of these initiatives, and examine how they will collectively contribute to facilitating future exploration and mining activity in New Zealand.

Jan 1, 2004

By C A. Fleming, C J. Ferron, P T. OÆ

A new process is described which allows for direct recovery of base and precious metals (Au and PGMÆs) from sulphide concentrates or other feedstocks. The process was developed initially for application to ores or concentrates that are too low-grade for economic treatment by the conventional smelting and matte leaching process (for PGMÆs). It is now believed that the process may be widely applicable to a variety of materials including PGM concentrates containing high amounts of chromium or magnesium. Operating conditions have been identified under which gold, the PGMÆs and the base metals dissolve simultaneously in a pressure leaching autoclave. The product of this leaching process can then be treated by one of several flowsheets, of which the preferred will likely involve solid/liquid separation, followed by precipitation (or adsorption on activated carbon) of gold and the PGMÆs, followed by copper solvent extraction/electrowinning. Depending on the concentrations of nickel and cobalt, the copper raffinate would either be partially recycled to the autoclave to allow Ni/Co concentrations to build up, or it would proceed directly to a Ni/Co refinery. This paper deals with the pressure leaching process and the recovery of gold and the PGMÆs from the pressure leach product.

Jan 1, 2000

Trucks are the primary means of bulk material transport in Open Pit hard rock mines worldwide. They are considered to be the most- flexible system available. The large number of trucks used in some mines provides flexibility. Spare units allow for the reduced availability of the single units. Trucks have however very poor energy efficiency. Only 40% of the consumed energy is for transport of the payload, the remaining energy is required to move the dead load of the trucks. With the increase in cost, pressure, mine operators are now looking for alternative methods to make their operation more economical. Energy conservation and increasing haulage distances and uphill haulage are major factors in many well established operations. New methods have already proven themselves as more economical alternatives. Belt conveyors are an alternative means of transport with much higher energy efficiency. They use up to 80% of the consumed energy for transportation of the payload. Energy costs for conveyors are 30% of the energy costs for trucks on level transport and as little as 15% for elevating payloads. Belt conveyors require much fear spare parts and wear components than trucks. A factor of one to two times applies for level transport and ten to twenty times for uphill transport.

Jan 1, 1986

By Braham B

The Australian mining industry isstill labouring under the impression. created by the Fitzgerald Report that it does not pay suffic- ient tax. This would appear to be the raison d'etre of the resource rent tax debate. The authors quantitatively compare the cash flows to the mine and government resulting from a large strip coal mine in central Queensland under a number of Australian and international taxation policies. The Liberal government policies are found to be internationally competitive while the Labor 1975 policy is excessively punitive. The present value of the returns to the public from the Liberal 1977 policy vary between three and six times the net present value to the mine, which belies the necessity for the imposition of a super tax. The levelling of a special royalty, excess rail freight, by Queensland could severely re- strict the development of new mines in the Bowen Basin. The impact of excessive freight rates is analysed on a combined strip-deep mine typical of the new projects nearing development in the region. Otherwise economic mines can be made marginal or even sub economic by this tax. Even with moderate rail freights, the mining tax laws of New South Wales are more favourable to the industry than are Queensland's.

Jan 1, 1978

By Han Kook-Nam, Lawson F

The recoveries of the three cobalt minerals in the Mount Cobalt deposit, cobaltite CoAsS, erythrite CO3(AS04)8H20, and new cobalt mineral with a composition approximating 2CoO.CaO.Fe203.2As205.11H2O were investigated using physical and surface-chemical processes.Over 80 per cent cobalt recovery was achieved by tabling a cobaltite-mineralized sample, while about 76 per cent cobalt recovery was obtained by dry feed magnetic separation of a sample containing erythrite and the new cobalt mineral. The resultant primary magnetic concentrate with a cobalt grade of 5.5 per cent, was able to be upgraded to 14.4 per cent cobalt by regrinding .and a further magnetic separation.Electrophoretic mobility - pH responses for each of the three cobalt minerals were found to be similar. Each mineral remained negative over the pH range 3 to 11 and was most negative at mildly alkaline pH values.Cobaltite was floated effectively with amyl and ethyl xanthate collectors under acidic conditions at collector concentrations of 10-2M to 10-5M. Erythrite showed a similar flotation response using 10-sM amyl xanthate. The practical application of these laboratory separations to an industrial process is suggested.

Jan 1, 1976

By J P. R de Villiers

The Vanderbijl Park sinter plant in South Africa was investigated to determine the reason for the production of very fine sinter not acceptable as feedstock for the blast furnace. A procedure was designed to generate representative samples and to prepare the samples for chemical and mineralogical analyses. Results from a mineral analyser showed that the samples are extremely heterogeneous and therefore the sampling and sample preparation methods had to be tested in order to produce representative samples. The high production capacity at the sinter plant could also give rise to sampling errors. The method designed involved sampling of the conveyor belt at the sinter plant every four hours for the duration of three days. The samples were then milled and split into smaller sections appropriate for analysis. X-Ray diffraction (XRD) and X-Ray fluorescence (XRF) analyses were conducted on the samples. The results showed a standard deviation of less then one per cent, which indicates that the samples were representative and that the method used was therefore adequate. Systematic differences in the phase proportions between normal and fine sinter samples were detected, with the fine sinter containing more haematite than the normal sinter. The sampling method employed gives added confidence that the differences are real.

Jan 1, 2008

By C Sennersten, A Hellicar, C Lindley

Traditional methods of resource modelling and mine planning rely upon geostatistical methods applied to exploration drill core data to derive a three dimensional model of the distribution of metal grades, quantised into rectangular prisms or blocks. The resulting block model is a primary input into short, medium and long term mine planning. However, block attributes are averaged or interpolated over a complete block, meaning that information at smaller scales is lost to the mine planning process. Grade engineering for new mining methods, such as the development of more accurately controlled blast designs, continuous miners for hard rock and sensors for rock properties that can be distributed along the operations process and value chain, allows excavation to be much more selective than traditional blasting, and provides data for driving earlier separation of waste from ore. This selectivity can be optimised if the resolution of resource models can match or exceed the spatial resolution of selective mining technologies. Opportunities for selective mining increase as a deposit becomes more heterogeneous. This leads to an interest in methods for estimating the distribution and characteristics of mineral heterogeneity within the ore-body. The objective of this work is to present some definitions of mineral heterogeneity, and to explore how heterogeneity as defined can be measured and inferred within ore-bodies.CITATION: Hellicar, A, Sennersten, C, Lindley, C and Evans, B, 2018. Heterogeneity assessment for grade engineering in complex ore bodies, in Proceedings Complex Orebodies Conference 2018, pp 11–13 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018