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One of the major changes in the resource industry in the nineties has been the re- internationalisation of the industry. The history of the resource business has been one of companies from the developed world utilising the cash flows from their operations to explore and develop mines in less developed regions of the world. This resource development has progressively generated wealth and economic development, which in tum, has led to a new generation of exploration and mining projects.   InSouth America, Chile had led the way in a mining resurgence, now closely followed by Argentina, Brazil, Venezuela and Peru. Although Chile has long had a significant copper mining industry, the pre-nationalisation phase was driven by American capital; the current phase has been spearheaded by RTZ - BHP at Escondida with Canadian junior companies, in particular, providing major speculative impetus. The Australian junior companies have not been significant in South America.   Although Canadian and USA exploration appears to be in decline, the mining industry, particularly in gold, is buoyant in North America. Interestingly, a number of listed and unlisted Australian companies are active, particularly in United States exploration.   Australian-based companies have dominated the South-East Asian exploration scene, especially in the Vietnam region. To date, the combination of political and legislative uncertainties have failed to lead to significant resource developments in this region. The area remains one of great potential, as exemplified by the exciting developments in Indonesia.   The Philippines has a history of mining, and this has been dominated by both local and North American operators. Both large and small Australian resource companies have a presence in the Philippines, and the development of the copper-gold potential could be impressive over the next decade.   The tales of the undeveloped mineral potential of China are probably rivalled only by the supposed strings of virgin Russian orebodies! Many Australian companies appear to have looked but few have chosen to proceed with Chinese developments. There seems little likelihood that China will, in the foreseeable future, rival South America as a target for Australian and North American resource capital.   Papua New Guinea has had an active, albeit chequered history in mining, with Australia long being the predominant source of exploration and development funds. The developing nation status of PNG has generated extreme uncertainty, with the current exploration scene all but dead. Most recently, the international flotation of Lihir Gold has tested the international and Australian investment community's commitment to PNG resource development.   The Australian exploration scene continues buoyant, although dominated by gold. The base metals scene is generating, on average, one significant base metal mine developed every couple of years. This is probably the fastest rate of significant base metal development in Australia's history.   The gold scene has been one of incredible dynamics, and there is no evidence that this momentum is waning. The development of new exploration techniques, together with a number of the companies reaching a critical size, has added to the momentum in the industry.

Jan 1, 1995

By X Sun, L B. Zhou, H Yi, X Tang, P Ning

The rapid industrialisation in China has consumed large amounts of various industrial raw materials, which has left behind large quantities of industrial solid wastes produced from the processes of mining, mineral processing and smelting. The storage of huge quantities of industrial solid wastes is an obvious risk to the environment and human well-being. As the first step to fully appreciate the scale of this risk, it is necessary to carry out research for developing a pollution source environmental risk assessment system (PSERAS), especially for the typical staple industrial solid waste (TSISW). This paper aims to discuss the frame of the PSERAS for TSISW for large scale production. This system consists of two aspects: predicted factors and accidental ones, which involve physical, chemical and biological risk assessments, on-site and during transportation process. Two analysis methods, the analytic hierarchy process (AHP) and fuzzy logic assessment (FLA) were used to handle the complexity of environment and non-quantitative data. The risk assessment system for such a complex objective is difficult and the assessment of relative factors is problematic through the usual quantitative analysis. With the proposed PSERAS, it is possible to define the risk class of pollution sources. Furthermore, the risk assessment results will be helpful to the decision-maker, especially when facing unknown risks in the environmental management of industrial solid wastes. In addition, by means of the PSERAS, risk factors can be ranked against their contributions to environmental risk, in order to calculate their relative priorities in decision-making.CITATION:Sun, X, Ning, P, Tang, X, Yi, H and Zhou, L B, 2012. Environmental risk assessment system for typical staple industrial solid wastes, in Proceedings Life-of-Mine 2012 , pp 301-304 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By O Ishiyama, L Lu

Sintering is the most economic and widely used agglomeration process to prepare iron ore fines for blast furnace use. Due to the depleting reserves of traditional high-grade iron ore, there have been considerable changes in iron ore resources available throughout the world, especially in steel mills in East Asia. Corresponding to the changes in the availability of iron ore resources, the amount of impurities in iron ore has been slowly increasing. Some of these impurities have been found to have deleterious impacts on sinter quality and sintering performance. In the meantime, an increasing number of large blast furnaces with inner volumes of more than 5000 m3 have been built that require more sinter and are often more demanding in terms of the quality requirements of the ferrous materials. Finally, sinter plants are facing increasing pressure due to more stringent regulations regarding their environmental impact. This paper gives an overall review of a variety of technologies developed worldwide to tackle the changing raw material characteristics and mitigate emissions from sintering operations.CITATION:Lu, L and Ishiyama, O, 2015. Recent advances in iron ore sintering, in Proceedings Iron Ore 2015, pp 61–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By H W. Wu

Occupational exposure limits for diesel particular matter (DPM) are progressively being adopted in a number of countries. Many of these follow the lead of the US Mine Safety and Health Administration initiated in 2008. In line with adoption of best practice it is accepted that all exposures should be reduced to as low as reasonably achievable. The management of diesel emissions and occupational exposures to those emissions requires an integrated strategy incorporating efforts from all key departments on a mine, including management, production, maintenance, supply and occupational health and safety.Australian coalmine longwall moves rely on the use of high-powered diesel equipment such as chariots and other machines that produce exhaust pollutants of gases and DPM. To reduce mine personnel’s exposure levels to DPM a hierarchy of controls can be followed. Minimising the use of diesel equipment, better operator positioning in relation to exposure source, using efficient engineering methods and adopting better ventilation to reduce concentrations through dilution are some of the controls that can eliminate exposures. Approaches generally adopted in Australian longwall mines currently rely on a combination of strategies such as optimisation of ventilation, use of diesel particulate filters and use of diesel tag boards that minimise the number of vehicles through recording entry and exit into working panels.A study has been undertaken into the mine ventilation systems currently in use during longwall moves within Australian modern longwall extraction mines. This paper reviews current longwall section ventilation systems and discusses evolving changes being adopted to address the more complex problems in dealing with section DPM during phases of the operational moves. The effects of DPM on crew members as well as the diesel equipment operators within a longwall section are examined. Issues that should be considered in designing the longwall section ventilation during the moves are discussed.CITATION:Wu, H W and Gillies, A D S, 2015. Review of ventilation optimisation strategies during longwall moves, in Proceedings The Australian Mine Ventilation Conference, pp 133–140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

Many block caving operations experience difficulties during undercutting, resulting in draw horizon damage, production loss and extensive drift repairs for the life of the block cave. This paper deals specifically with block cave undercut aims strategies, methodologies and management to avoid the problems indicated above.

Jan 1, 2000

By S Bluhm, R Funnell

Creative mine-designs are constantly being applied in the deep platinum mining industry in South Africa. Recently, this has resulted in deep hot mine-designs including room and pillar, bord and pillar or stall and pillar layouts and the use of in-stope trackless mechanisation. In these mines, the ventilation systems use refrigerated air and high fan pressures and as a result ventilation leakage can have a huge impact. Leakage is a serious impediment to cost-effective operation and potential leakage in future projects is a major factor in judging project viability. This paper describes certain mine layouts and quantifies the extent of the leakage. Based on typical field data, a range of seals from ævery poorÆ to ævery goodÆ was defined and used to estimate overall leakage. Within these mine networks the ventilation pressure, temperature and density all vary significantly and with the multiplicity of leakage paths it was necessary to make use of the VUMA-network simulation package. For the examples examined, the leakage was found to be up to 85 per cent for æpoorÆ category seals and up to 50 per cent for ægoodÆ category seals. The total air flow (and refrigeration) requirements grow exponentially with strike distance due to the compounding effects of higher pressure and more leakage paths. It is shown that beyond certain depths and strike distances the leakage will become so great that it will be impossible to operate cost-effectively û even with ægoodÆ seals. Indeed, in these examples the projects were not considered viable in their original format because of the high ventilation-cooling costs and the mine-designs were modified to include footwall drive systems û the cost of which was justified by the reduced strategic risk to operating ineffectiveness due to leakage.

Jan 1, 2005

By T A. J Hopper, S Mukkisa, K-O Ott, D Palmer

RIG Technologies has developed new technology that can successfully acquire high quality natural gamma ray (GR) and hole deviations, downhole while drilling, on reverse circulation drills. This technology survives the hostile downhole environment with shocks of between 400–2500 g for 7– 10 days at a time. The Logging While Drilling (LWD) service eliminates the need to run in-rod surveys, either by the driller or by wireline trucks and crews. This time saving is in the middle of the drilling process, thus enabling drills to keep drilling and increase their productivity. Additional to the natural GR and directional survey, the downhole tool is equipped with sensors to measure the downhole dynamic response of the drilling system providing insights into rock hardness, density and potentially clay types. These parameters have never been acquired behind the hammer before and coupled with surface measurements from the drills themselves, form a rich data set for trainable machine learning algorithms shortening the time to receive advanced geophysical answer products from sometimes months, to live feeds directly from drills (Hopper, 2019). Alive, high speed, two-way data link between surface data acquisition systems and downhole geophysics tools has been established and incorporates calibrated surface measurements of dynamic forces directly on the drill string to match up with those measured downhole. Receiving live streams of natural GR and hole deviation surveys as the drill is drilling allows true remote decisionmaking with live data available anywhere in the world. The combined data from surface and downhole dynamics builds a data set that could begin to enable true optimisation of autonomous drilling processes.

Nov 8, 2021

The National Economic Viewpoint? Any substantial project undertaken by private enterprise would normally be subjected to a Discounted Cash Flow analysis of its commercial viability, and would proceed only if the rate of return was judged satisfactory. A 'national viewpoint' analysis attempts to do the same but from the viewpoint of the community as a whole. The objective is to ensure that those projects are undertaken which yield the best return, economic and social, to the nation as a whole.

Jan 1, 1984

By M Simanjuntak, A M. Supomo

PT Freeport IndonesiaÆs copper/gold operation disposes of approximately 222 000 dry metric tonnes of tailings per day via two thickeners. Reduction of the flocculant dosage rates in each of the tailing thickeners has been achieved with the installation of Clarometers«, modifications to the existing operating DCS control strategy and a change in plant flocculant. This has reduced the flocculant consumption rate in the last twelve months by approximately 20 per cent. It has also highlighted the disparity in the settling rates of the two thickeners. Collaborative efforts between Cytec technical site engineers and Freeport operational personnel have made possible the overall gains achieved in the tailings thickener optimisation.

Jan 1, 2003

By S J. Kim, S W. Kim, L Tomas da Rocha, S Jung

Al2O3 has been regarded as a harmful gangue component in iron ore, especially causing reduction degradation in industrial sintering of iron ore. The current study aimed to utilise low-grade iron ore containing high Al2O3 content in sintering process. In order to counteract the adverse effect of Al2O3 on reduction behaviour of iron ore sinter, mill-scale and calcined dolomite were chosen as FeO- and MgO-bearing materials. Firstly, mill-scale was added to high Al2O3 sinter and addition was optimised as 10 wt per cent, then calcined dolomite was added further. Magnetite and magnesio-ferrite were identified as the major phases in iron ore sinter when adding mill-scale and calcined dolomite. As the dosage of calcined dolomite increased beyond 4 wt per cent of in sinter mix, unreacted MgO particles were observed, which is ascribed to the limitation of MgO dissolution into magnetite matrix. Both mill-scale and calcined dolomite were effective in improving compressive load and Reduction Disintegration Index (RDI) of iron ore sinter although its reduction degree was highly decreased. The addition of both FeO and MgO-bearing materials to high Al2O3 sinter has a potential to improve the sinter quality, also contribute to the recycling of industrial by-product. However, the amount should be optimised in views of phase development and deterioration of reducibility.

Jun 19, 2024

The subject of the present paper will be combustion of fuel and as the combustion of fuel requires a certain amouut of air to effect combustion the question might be asked what is air?Air is composed, we will say, principally of two gases, oxygen and, nitrogen, but our business is with the former gas, and its leading feature as a supporter' of combustion. In point of fact no fire will burn without its presence, nor can animal life be sustained when this gas ls absent, because it is the life-sustaining element. For example, if we take a piece of charcoal, which is pure carbon, and burn it in the open air combustion takes place in the union of the carbon of the charcoal with the oxygen of the air, forming the compound known as carbonic acid (0.0.)The rust we see on iron and other metals is a kind of slow combustion, which is termed oxydation. When oxygen unites with any other element heat is given off in the process, and it may be here stated that the most intense heat is produced, by burning the two gases-oxygen and hydrogen in precisely the same proportions as that forming water.

By S Wan, F Zhang, J You, K Tang, X Tang, C Bessada, A Canizarès, Q Zhang, L Lu

Microstructure of CaO-SiO2-based glassy samples with various Al2O3 contents were examined quantitatively by Raman spectroscopy and 27Al MAS NMR (magic-angle spinning nuclear magnetic resonance). Sequence of multiple cluster models of aluminosilicate system modified with Ca2+ and Na+ cations have been designed, and Raman spectra simulation were carried out after geometric optimisation by quantum chemistry (QC) ab initio calculation. The functional relationship between Raman scattering cross-section (RSCS) and stress index of silicon-oxygen tetrahedron (SIT) for aluminosilicates was established, which was applied to the calibration of experimental Raman spectra. Some five-fold coordinated aluminium (AlV, around 5 per cent) and less than 2 per cent sixfold coordinated aluminium (AlVI) were detected by 27Al MAS NMR, while most of aluminium remained in tetrahedral sites (AlIV). The hyperfine quantitative results of Raman spectroscopy and NMR showed a gradually production of AlIV with addition of Al2O3, along with the significant adjustment of Qi species distribution, in which Q1, Q2 reduced and fully polymerised Q4 increased while Q3 showed a non-monotonic variation and obtained the maximum at Al2O3 = 18 mol per cent. Furthermore, the effects of aluminium to bridging oxygen bond types (T-Ob, T = Si, Al) and the degree of polymerisation were also discussed in detail. The evolution of microstructure and its correlation with the viscosity of CaO-SiO2 based melts, incorporating various Al2O3 additives, have been investigated by employing in situ high temperature Raman spectroscopy at 1823 K and viscosity model. These structural features related to composition are essential theoretic foundation to understand their properties. The average Qi evolution culminates in an overall enhancement of the degree of polymerisation. Viscosity was determined utilising a rigorously selected viscosity model, elucidating a consistent upward trajectory as Al2O3 content is incrementally added. Furthermore, a quantitative analysis of the relationship between viscosity and structure was conducted based on the average number of non-bridging oxygen per network-forming tetrahedron (NBO/T). It provides valuable insights for examining and predicting viscosity behaviour of aluminosilicate systems.

Aug 21, 2024

By M Tessier, M Pahkala, L Sletmoe

The Red Lake mine is one of the richest gold mines in the world. The primary mining methods are overhand and underhand cut and fill. Starting in 2003, Goldcorp initiated an expansion program at the mine. The expansion includes a new 6.55 m diameter hoisting shaft currently under construction. The shaft will be driven to a length of over 2180 m. The shaft will be used as a primary ventilation intake to the mine. In addition to the new hoisting shaft, a return air raise is being driven approximately 1690 m from surface. This raise will be a parallel return to the existing mine infrastructure. This paper describes the ventilation and climatic analyses performed in support of the expansion project. The study included a full mine ventilation survey, in situ rock mass measurements, analysing options related to mine layout, airway sizing calculations, air heating options, and climatic simulations. Specifications were prepared for an air heating system and main and booster fans. Analyses were also performed related to heat in the stoping areas namely caused by auxiliary fans and backfill with high cement content.

Jan 1, 2005

A pilot plant was constructed for the low temperature carbonization of Wallarah (N.S.W.) coal at the rate of 300 lb/hr. The design was based on an entrained state carbonizer developed by Parry and D.S. Bureau of Mines co-workers. Prior to delivery to the client, the plant was successfully operated over periods of several days duration.INTRODUCTIONIn September 1961, the Australian Mineral Development Laboratories (A.M.D.L.) was engaged by the Broken Hill Pty. Co. Ltd. (B.H.P.) to design, construct and test an entrained state coal carbonizer with a capacity of 300 lb/hr of Wallarah (N.S.W.) coal. Char product was required within the specification 15·5 -I- 1 per cent volatile matter. The design was to be based on a pilot plant developed by Parry and others in the D.S. Bureau of Mines Coal Research Laboratory at Denver, D.S.A. The method involved the carbonization of fine coal by entrainment with air in an externally heated reactor. The heat required for the carbonization of the coal was to be supplied to the bed both through the reactor walls, and also by internal combustion of products in the bed. Several D.S. Bureau of Mines Reports of Investigations weFe used as the main guide to the physical layout and proportions of the plant. However, the individual units required detailed designing, before engineering drawings could be prepared and fabrication begun.A 10 ton sample of crushed Wallarah coal was used for preliminary testing of the plant. The first test run on the pilot plant was carried out in February, 1962. After some modification a second test of longer duration was conducted in August, 1962. These operations aimed at running in the plant and also at determining the operating temperature to produce specification char and the maximum capacity of the...

Jan 1, 1963

By A Dal-Corobbo, R Zick

The coal mining industry is now faced with new regulatory requirements that limit the discharge of chlorides into receiving streams. To meet these new regulatory standards for treated mine water, a zero liquid waste approach was developed using advanced treatment technologies. The approach described in this paper will generate clean water for reuse in various energy endeavours or discharge to the environment, with no substantial liquid or solid waste from the treatment process leaving the site.CITATION:Dal-Corobbo, A and Zick, R, 2013. Zero liquid discharge in coal mining operations, in Proceedings Water in Mining 2013 , pp 221-226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

This paper discusses equipment replacement strategies and specifically addresses the upgrading of technologically superseded equipment. The process of equipment replacement evaluations is reviewed, and areas have been highlighted where currently accepted practice results in a bias towards retaining existing equipment longer than otherwise justified. The Discounted Average Cost Method is described and the advantages of the technique for this style of decision making discussed. Several key issues influencing the replacement evaluation are also presented together with examples from recent consulting work.

Jan 1, 1992

By S Maritsa, E K. Chiw, S M. Masuka, ika, T Chisahwira

The challenges facing the iron and steel industry on a global scale include depletion of resources, excessive energy consumption and CO2 emissions. The demand for iron products in Zimbabwe is increasing due to massive infrastructural development like the expansion and improvement of mines, transportation systems and water reticulation systems. In Zimbabwe, cast iron is mainly produced from recycling scrap metals. However, there is currently a shortage of scrap, which has resulted in the vandalism of state-owned properties such as bus terminals and railway wagons and lines. Nevertheless, Zimbabwe is rich in limonite ores, which are idle, and it is the aim of this research that this ore be effectively used to produce feed for the blast furnace. The Blast furnace is still the dominant route for producing cast iron where sintering and coking processes are the main routes for preparing the Blast furnace feed. Sintering limonite ore fines produce a product of poor grade because of the high value of loss on ignition that has a negative impact on Blast furnace efficiency. Furthermore, the sinter plant and the coke making plant are a source of huge environmental pollutants. Since low-grade Zimbabwean coal fines are also available in abundance, they were used in the preparation of the composite materials ensuring maximum utilisation of this resource. Results showed that the limonite ore-carbon composite pellets sample with the binary basicity ratio (CaO/SiO2) of about 0.27 and coal addition of 2.5 wt per cent achieved above the minimum physical quality requirements for pellet of drop number of at least 4, a dry compression strength greater than 2.2 kg/pellet and an indurated compression strength greater than 250 kg/pellet. Limestone was used as the binder avoiding the addition of more impurities from bentonite since the limonite ore has a high SiO2 content of about 8.78 wt per cent.

Sep 18, 2023

By A Halim

The European Union (EU) have recently issued new Threshold Limit Value-Time Weighted Average (TLV-TWA) for diesel exhaust contaminants, which are CO, NO2 and DPM. The new limits for CO and NO2 were issued in 2017 whilst the one for DPM was issued in 2019. However, in order to allow EU mines to formulate strategies to comply with these new limits, the EU granted a transition period in which mines could use the old limits until the new limits are enforced. The new limit for CO and NO2 will be enforced from 21 August 2023 whilst the one for DPM will be enforced from 21 February 2026. The new limit for NO2 and DPM is very low, 0.5 ppm for NO2 and 0.05 mg/m3 of Elemental Carbon (EC) for DPM. Combination of these two limits would be the lowest among all mining jurisdictions worldwide. It poses a huge compliance challenge to EU mines if they keep using diesel machines. Therefore, a study and a field trial were carried out by the author in 2019–2021 to investigate whether replacing diesel machines with Battery Electric Vehicles (BEVs) would be the best answer to this challenge. This paper outlines results of this study and field trial.

Oct 12, 2022

By K Eglinton

The extractive industries response to community engagement due to social and political pressures in the 1980s and 1990s was the starting point of development leading to the modern function of corporate social responsibility.Challenged by communities who have greater access to information, demand greater transparency and responsibility of corporate organisations and who possess greater awareness of the communities they participate in, the mining sector faces another step change in how it approaches and integrates corporate social responsibility, transparency and engagement.Mining is seeking reserves of lower grades, in more sensitive environments and in countries with minimal transparency and governance. Not only are the locations changing but so to the stakeholders to engage with and issues to contend with. An increasingly savvy opposition, including not just the ‘green hippies’ but the Gen-Ys interested in the wider sustainability debate and Baby Boomers moving to life style environments, are now questioning mining’s behaviour and encroachment into ‘their space’. Issues including effect on lifestyle amenity, property value, energy efficiency, social provision; concepts such as ‘doing more with less’, participatory engagement, increasing transparency and balancing economic, environment, cultural and social aspects are becoming the norm.The traditional model of supporting local communities, communicating plans and providing employment, community investment and indigenous support programs is not enough. Our industry faces challenges on multiple fronts. It must now be able to address these from a personal/community perspective if it is to remain relevant within communities and play a role in addressing the global sustainability issues.This paper draws on corporate social responsibility trends, integrated functions and implementation approaches through the application of activities within Newmont operations across Asia Pacific.The approach presented works on the philosophy that communities do not necessarily have to like what we do, but should be able to identify and recognise the way in which we involve them in decision making, communicate our intentions and respond to issues.

Nov 22, 2011

Politicians and economists talk glibly about the so-called knowledge revolution. The reality is that knowledge is fundamental to economic progress. Consequently there have been many technological revolutions. The global impacts of the invention of the steam engine and the development of the frozen meat industry are well known. Another less publicised technological advance occurred in Central Otago late in the nineteenth century. This was the adaptation of the bucketladder dredge to the mining of placer deposits. A product of over 30 years experimentation and innovation, New Zealand dredging technology was taken to the Risdon Iron and Locomotive Works, San Francisco by R H Postlethwaite, a Dunedin based mining engineer. New Zealand-style dredges built by Risdon operated successfully in California, Alaska and the Yukon. Californian engineers assimilated the best features of the New Zealand dredges with American (Bucyrus) designs to produce a standard for the worldwide placer mining industry.

Jan 1, 2003