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One distinctive feature of the global mining industry approaching the twenty-first century is the worldwide commitment of mining houses to large-scale projects in developing countries. One good example is BHP's development of the Escondida copper project in Chile. The Escondida orebody was discovered in 1981 and construction began in July 1988. Mining began in December 1990 at a design capacity of 320 000 tonnes of copper contained in concentrate. Out put has grown significantly and shortly Escondida will become the largest single copper mine in the world producing copper at the rate of 800 000 tonnes per annum, including 80 000 tonnes of copper metal. Escondida provides a case study of the development and growth of a large-scale mining operation in a developing country. Key elements have been innovative financing, the management of country risk, the recruitment of an excellent workforce, the use of advanced technologies and best practice in environmental management and community relations. Escondida is one of the global mining industry's success stories in the 1990s.

Jan 1, 1996

By N L. Turner, K Ehrig, V Liebezeit, D J. Robinson, L L. Kuhar, N Francis

Conventional industry tests used to determine leach recoveries are often fully monitored and may be time-consuming and expensive. Such tests may be limiting in geometallurgical applications where large numbers of samples are required to be processed for characterisation of an ore deposit. BHP Billiton currently use a fully instrumented leach test for characterisation of Olympic Dam uranium-rich samples. Researchers at the Commonwealth Scientific Research and Industrial Organisation (CSIRO) were approached to develop an alternative to these full-scale leach tests that could allow for the ranking of samples in terms of their leachability. The novel geometallurgical test was required to use samples of small mass and be affordable and rapid.Three leach test protocols were pursued in developing the small-scale tests. Kinetic leach tests were performed using mild conditions at higher pH, low temperature and low oxidation reduction potential, moderate conditions at intermediate pH, temperature and oxidation reduction potential and aggressive conditions at lower pH, higher temperature and higher reduction potential.This paper presents results from 44 leach tests on 11 samples with varying uranium mineralogy. The developed small-scale tests correlate well with data from the more costly conventional industry laboratory tests, indicating the possibility of using this alternative test as a geometallurgical leach proxy. Simple regression analysis confirmed the importance of pH, reduction potential and temperature on uranium extraction. Experimental data were fitted to published leach models to predict uranium leach extraction for a range of operating conditions.The ultimate aim of the test work is to combine a limited number of large-scale calibration tests, a large number of small-scale geometallurgical tests and leach models for geometallurgical sample characterisation and evaluation of a wide range of scenarios or processing options.CITATION:Turner, N L, Kuhar, L L, Francis, N, Liebezeit, V, Ehrig, K and Robinson, D J, 2013. Development and testing of a small-scale uranium leach for geometallurgical applications, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 345-350 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

Development and Validation of Ore Characterisation Test and its Use in Variability Campaigns of Comminution Circuits Impact testing was developed by assessing the fragmentation characteristics of ore samples after controlled impact. Standard methods are, however, limited to relatively large and coarse samples, which thus precludes their use in early stages of projects, as well as where only drill cores are available. The method described in this paper is based on the same concepts of controlled ore breakage, but using relatively smaller samples. It is particularly useful in assessing the variability of ore characteristics in early stages of greenfield projects, as well as in predicting the performance of existing grinding circuits. A validation program was carried out in which a good adherence to the original test results was obtained. The results were used for (a) simulation of a copper comminution circuit as a function of the ore characteristics, and (b) evaluation of sampling protocols used for assessing fragmentation characteristics.

Sep 13, 2010

Permitting, engineering and evaluation, detailed design and construction aspects of the Golden Cross goldmining project in New Zealand are briefly reviewed. The extremely lengthy and complicated governmental approval process together with the delaying tactics of opponents of the project are outlined and comment is made on aspects of the draft legislation proposed as part of the overhaul of New Zealand's resource management laws.

Jan 1, 1990

By F A. Rosyid

Mineral resources are national assets which must be capitalised for national development. Those assets should be transferred into real economic capital and then into social capital to achieve national/regional prosperity. Successful development in the mining industry will depend on the correctness in determining the role of mining industries for regional development. Using the context of sustainable development, this paper will analyse the concept and process of mining industry development as an accelerator to achieve regional sustainable development, using the mining operations of PT Newmont Nusa Tenggara (PT NNT) in Batuhijau, Sumbawa Barat Regency as a case study. In the premining activity phase, Sumbawa Barat was dependent on the agricultural sector. Agriculture contributed around 40 per cent of the regional gross domestic product (GDP). Meanwhile, in the activity phase, mining became the sector with the biggest contribution to regional economy. From its operation in Batuhijau, PT NNT contributed around 70 per cent of the regional GDP per year since 2001. In year 2000, the GDP had increased 170 per cent from its figure in 1999. However, due to its depleting reserve, PT NNT will finish its activity in Batuhijau by year 2015. Consequently, the Government of Sumbawa Barat Regency must develop other sectors in the post-mining phase to sustain economic development. Based on location quotient (LQ) and input-output analyses, Sumbawa Barat should develop its priority sectors, ie agriculture, trading and hotel, services and construction to achieve sustainability after mining life. Development of these non-mineral sectors is expected to sustain economic growth in the region.

Jan 1, 2008

By Jansen N

Production from the narrow, high grade silver-lead-zinc orebodies below 15 level commenced in mid 1985.Geological, mining research and recent mining experience determined that a mechanised drill, fire and muck cycle would be the most suitable method.Ground conditions are predicted to be worse than in other cut and fill (MICAF) areas at Isa Mine, owing to the increased depth, more variable dip of the orebodies and the increased effect of major geological structures.Mechanised ground support and tight filling techniques feature in controlling these expected adverse ground conditions.

Jan 1, 1985

By T Davis

The 500 orebody in the upper levels of Mt Isa Mines in north-west Queensland was mined by sublevel caving and block caving from 1962 to 1969. The hot and reactive rock mass of this orebody provided significant mining challenges including ground temperatures above those resulting from the geothermal gradient. Recently Xstrata Copper has been studying the potential to mine this orebody by modern caving techniques. Part of the study process has included re-accessing the ore zones for diamond drilling and trial development. A cross-cut trial drive, the first primary development into the orebody in more than 30 years, encountered a temperature increase in development holes from low sixties to almost 80¦C in less than 10 m advance. The issues associated with managing this risk include sourcing suitable quantities of reactive ground explosives for a single small heading and the temperature limitations of the explosives and detonators. Risk management outcomes included controls to mitigate the safety and reliability risks relating to misfires. The control that dealt directly with the challenge of continuing development in elevated temperature ground was to cool the holes before and during charging. The most effective and practical cooling medium proved to be water. Rapid rock temperature recharge time meant cooling had to continue as close to firing as possible. Reticulation systems were constructed to allow cooling to take place up until withdrawal for firing. No misfires occurred with the cooling system and additional controls in place. This proved that developing safely and effectively in the elevated ground temperatures of the 500 orebody is practicable.

Jan 1, 2008

By Thompson J

A programme of testing and evaluation has been in progress at Isa Mine for the last four years with the objectives of rationalising ground support practices, improving installation quality and increasing productivity of ground support functions.Numerous innovations have been successfully implemented. These include the introduction of swellex rockbolts as the major form of temporary support, the use of splitset rockbolts as the primary means of support for the hangingwalls of cut and fill stopes and the introduction of dowels with pumped cement for general long term support.The installation of swellex bolts has been successfully mechanised throughout the mine using Tamrock automatic rockbolters and Atlas Copco BUK 11R drilling rigs modified for this purpose.

Jan 1, 1985

A general outline of the significant features in the quality and manufacture of the more common refractories is given. Where possible, linkage between quality development and control and service applicationhas been shown and explained. INTRODUCTIONThe refractory industry is no stranger to change. New processes and revision of old processes in other industries are the harbinger of new and revised products in refractories.Few of the changes are dramatic; generally they are evolutionary rather than revolutionary. New developments are additional to, and inclusive of, established practice.Therefore in this paper it is necessary to repeat much of what is already known in order to show the development taking place.FIRECLAY REFRACTORIESGeneral technology Fireclay refractories are the most common, the most varied and the most versatile of all refractories. Virtually any composition of silica and alumina up to the composition of kaolin is possible. For purposes of comparison they may be classified in the Continental fashion in accordance with chemical composition or in the American way according to "duty". That the two methods are equivalent is shown by an inspection of the alumina-silica diagram of Bbwen and Greig (1924). 'Fireclay refractories are composed of a glassy and a crystalline component derived from the chemical and physical nature of the raw materials used in their manufacture.

Jan 1, 1961

The introduction of new technology into thegold-mining industry has been encouraged in recent years by increases in the price of gold andthe necessity for costs to be contained.At most new gold mines, run-of-mine millingis preferred over crushing and multistage milling, and this change at the head of the circuit leaves no place for the manual sorting of ore and for gravity concentration in the mill circuit.Flotation continues to hold its place in goldrecovery. However, a decline in the demand forsulphuric acid may limit the amount of pyrite thatcan be roasted before cyanidation.

Jan 1, 1984

By Howlett P. F, Courtley S

A problem with secondary breaking at one of the mines of Pasminco Mining led to a study of new rock breaking technologies. Many of the techniques being developed had emerged from the thrust in the USA for continuous drill=break excavation. Such approaches to rock breaking highlighted the applicability of what would normally be classified as tunnelling techniques, to the secondary breaking sector - and possibly the reverse. As a direct result of the investigations for suitable technologies, Pasminco Mining supported the development of two improved rock breaking methods specifically targeting secondary breaking, one of which could be applied to continuous excavation.

Jan 1, 1993

By Whitworth NR, Fox MJ, Henley RG

The coal mass flow monitor was developed to measure the instantaneous mass flow rate of pulverised coal to the copper reverberatory furnace at Mount Isa. The instrument was calibrated with an isokinetic coal sampler which was installed immediately downstream from the coal mass flow monitor. Readings from the coal mass flow monitor were used to control the feedrate of coal to the furnace and this helped to stabilise the furnace operation.Coal samples obtained from the isokinetic coal sampler were also sized using a Leeds and Northrup Microtrac analyser. The coal size was critical to reverberatory furnace performance. These developments significantly improved the overall combustion control of the furnace and gains of ten percent were made in the furnace thermal efficiency. Testwork on an auxiliary arch coal burner is also reported.

Jan 1, 1985

By Just GD, Phillips R

The application of high pressure water jet technology to the drilling of longholes in coal has resulted in the development of a system currently capable of drilling to lengths greater than 200m. Field tests at the German Creek Mine have demonstrated directional control of the holes within a 0.5m section of the seam. Initial application of the technique at the German Creek operations is for drilling methane drainage holes. These developments, in three stages, result from support by the National Energy Research Development and Demonstration Council

Jan 1, 1991

By J Caron, M Athayde, F Lavoie, R Joyce

Decarbonisation has become a major challenge for the global steelmaking industry, turning towards new technologies aimed at carbon footprint reduction, which on its own accounts for approximately 9 per cent global emissions. The iron and steel industry represents a ‘hard to abate’ sector, where much of efforts are currently being deployed into initiatives aiming to decarbonise the ironmaking through the use of green hydrogen, carbon capture utilisation and storage and state-of-the-art operation of current technologies, while little efforts being deployed to find carbon-efficient solution to iron ore burden preparation, where high-grade iron concentrate will increase in importance to ironmaking regardless of the chosen reduction route. Quebec Iron Ore (QIO), a subsidiary of Champion Iron Limited (Champion), produces high-grade hematite concentrate with one of the lowest carbon global footprints. Still, QIO is partnering with its clients to the development of burden solutions to minimise CO2 emission, in the seek for a decarbonised steel. In a strong technological partnership, Binding Solutions Limited (BSL) has developed a novel, coldbinding technology to provide a cleaner, more cost-effective alternative to induration. The technology allows miners and steel producers to reduce Capex significantly and reduce energy consumption and CO2 emissions by 90 per cent. QIO and BSL have partnered to adapt the disruptive cold binding technology developed by BSL to QIO’s concentrate to produce a high-quality low emissions iron ore agglomerate. This paper describes the efforts taken to further develop BSL’s cold binding technology and its application to QIO’s high-grade iron ore concentrate to produce a hematite cold bonded briquette (hCBB) showing comparable performances with high quality seaborne fired pellets.

Nov 8, 2021

By Y L. Ma, Y Yang, M Chen, W Bruckard

To improve the understanding of the reactions and mechanisms occurring during the leaching of sulfide ores at high temperatures a range of advanced characterisation and sensing tools have been combined to provide a sophisticated and powerful methodology to examine sulfide leaching systems. These include advanced electrochemical methods, surface chemistry and materials characterisation techniques such as synchrotron X-Ray Absorption Spectroscopy (XAS), X-Ray Photoelectron Spectroscopy (XPS), Scanning Electrochemical Microscopy (SECM), and in situ X-ray diffraction (XRD), together with new robust solid state chemical sensors for in situ real time monitoring of key aqueous chemical parameters. The methodology was employed to investigate various sulfide mineral leaching processes. For example, oxidation of arsenopyrite at elevated temperature involves complicated multiple reactions and the process is strongly influenced by the solution conditions, component speciation and mineralogy. The methodology was used to study this system both ex situ and in situ to gain a detailed understanding of the complex chemical reaction mechanisms operating. These mechanisms are discussed in terms of the observed leaching efficiency. The application of this methodology enables complex sulfide leaching systems to be understood more fully such that process efficiency can be improved.

Aug 24, 2022

By Wiltshire PG

The process uses sodium hydroxide and sodium nitrate reagents as in conventional Harris refining plants, selectively removing the arsenic to the caustic phase at an operating temperature of 420-450¦C. A novel feature of the process concept is continuous treatment of loaded caustic slag for recovery of arsenic as a sandy crystal product suitable for further processing to arsenic trioxide. A large pilot plant was constructed and operated over a period of 3 years to develop materials handling techniques and equipment components and to prove the concept. Stable operations were achieved at equivalent capacities of 200 tonne/yr arsenic removal. The process is being considered in plans for expansion of bullion softening capacity at Port Pirie.

Jan 1, 1984

In recent years a large amount of work has been done at various plants overseas, and also at Broken Hill Associated Smelters, Port Pirie, South Australia, on the use of Dwight Lloyd sintering plant gases for sulphuric acid manufacture by the contact process.Several plants have modified their sintering machines and operating procedure, and some have adopted gas recirculation techniques, to obtain a relatively high proportion of the sintering plant gas at an S02 concentration acceptable to a contact acid plant 1.These adaptations were investigated at Port Pirie, and it was found that gases of suitable S02 concentration could be obtained. The results justified installation of a contact acid plant and a decision was accordingly made in 1949 to construct such a plant.However, the local conditions presented some difficulties not generally encountered at other plants, the chief differences being:a. For maintenance of production of 98% H2S04 , an unusually high S02 concentration is required, because of the prevailing high temperature 'of the purification train cooling water.b. The entire sintering operation is conducted on two large machines, 55ft. x 10ft., operating in series as "First" and "Second over" machines (a two-pass roast.) Any interruption" to either machine causes a complete interruption of plant operation and gas flow.

Jan 1, 1951

Cannington Mine is an underground, hard rock, metalliferous mine located in North-Western Queensland, Australia. Weld mesh is installed to prevent the failure of rock from between the installed reinforcement elements. Corrosion reduces the capacity and life expectancy of mesh and presents a real hazard to underground personnel and equipment as it reduces the effectiveness of the support system. Corrosion influences the economics of the mining operation through the need to conduct rehabilitation of the ground support which involves re-installing new mesh or shotcreting over the affected mesh to protect it from further corrosion. The requirement for rehabilitation is determined by the geotechnical engineer based on an individual visual assessment with little or no engineering input. It was identified that a more quantitative method was required that considered the safety and economic risks involved. A project was undertaken to develop a simple method to evaluate corroded mesh and to provide selection criteria for rehabilitation. A weld mesh corrosion classification has been developed that relates the average wire diameter of corroded mesh to the remaining capacity of the mesh. Accompanying selection criteria provides recommendations as to when rehabilitation may be required based on the estimated residual mesh capacity, the remaining development life, and the level of personnel exposure.

Nov 25, 2010

By M, C Silveira, C Ellice, D Christensen

Peak Gold Mines (PGM), a member of the Rio Tinto Group, is an underground and open cut gold mining operation located near Cobar, NSW. A multi-phase study was initiated in 2001 in support of developing a dry æmoisture store and releaseÆ cover system design for the PGM tailings dam, which contains potentially acid-forming tailings material. The first phase consisted of characterising the tailings and potential cover material (waste rock from an open cut operation) as well as soil-atmosphere cover design modelling. The second phase involved construction of two cover system field trials on the tailings dam and installation of a variety of field instruments to monitor the hydraulic performance of the test covers during all seasons of the year. Field performance monitoring commenced in April 2002 and will continue for a minimum of two wet-dry climate cycles (third phase), prior to using the field data for calibration and subsequent validation of numerical models developed for the cover system trials (fourth phase). This paper describes the work completed for the first two project phases and also discusses the initial performance of the cover system trials.

Jan 1, 2003

By A Mortazavi, M Akhmedya

Mining is recognised as being one of the most dangerous industries in the world due to the difficult working conditions. Working in such hazardous circumstances in an underground mine often results in a variety of accidents. The working conditions at Kazakhstan’s underground mines have deteriorated owing to a lack of a risk-reduction plan and methodology. This paper evaluates different underground mines in Kazakhstan and demonstrates the employed mining method and the observed failure modes. Risk assessment has long been recognised as a valuable technique for preventing accidents. In the underground mining sector, risk assessment tools play an important role in avoiding work-related accidents. However, geotechnical uncertainty is a significant source of severe incidents like stress-induced roof collapse, wedge failure, seismicity etc, which result in human and financial losses. A geotechnical risk assessment performed early in the mine design process might assist justify a different mine design component, such as different support systems for a dangerous location within the mine openings during mining. The goal of this research is to create a damage/failure database aiming at the development of a geomechanical risk assessment methodology. This work identifies a thematic structure linked to risk assessment and management for the examined Kazakhstan mining sector. As part of the developed database, the dominant modes of failure within the Kazakhstan underground mining conditions were investigated. The study will provide opportunities to establish future research objectives for Kazakhstan’s mining industry where there are significant gaps between state-of-the-art research and mining operations in practice.

Nov 29, 2022