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Truck fires in a tunnel can create heat release rates (HRR) significantly higher than 100 MW. Because of a fast spread of smoke and heat the self-rescuing period is shortened significantly. Furthermore, it was experienced that firefighters are not able to approach the fire because of enormous heat and radiation. As consequence, the fire may spread to adjacent vehicles, which is reported for distances of more than 50 m. Tunnels can be damaged severely by fires and the repair works causes long closing time of tunnels. In addition to direct costs for the refurbishment of the tunnel, further economic losses will occur due to the closure time. Conventional deluge systems in Japanese and Australian road tunnels have been known since the 1960s. During the last years the research work was concentrated in the development of more effective and cost-effective solutions based on water mist technology. Orientating fire tests as well as specifications of minimum requirements were carried out within the European research project UPTUN. This basic work was extended by the safety of life in tunnels (SOLIT) research project, funded by the German government. The scope of SOLIT was not only to study the effects of water mist fire suppression systems in tunnels, but also the interactions with other safety systems, such as fire detection, passive fire protection or ventilation. Furthermore, the integration of active fire suppression systems into a holistic tunnel safety system was part of the work program. Within this research project a large-scale fire test program with more than 50 fire tests, including 25 truck fires with a potential HRR of almost 200 MW, was carried out in the test tunnel of San Pedro des Anes (Spain). Furthermore, a two-week testing and training period with the Madrid Fire Brigade was carried out after the SOLIT program. Two fundamental results were achieved during the fire tests:Primarily, water mist systems are able to control the HRR of fires in tunnels, so the atmosphere will be improved significantly. Hazardous effects of toxic smoke on people will be reduced and due to the reduction of temperatures and radiation, a firefighterÆs approach is improved significantly. Furthermore, the fire spread will be hampered and the thermal load on the building structure also be reduced. Secondarily, due to positive interactions with the ventilation system, the effectiveness of a tunnel ventilation system, longitudinal as well as semi-transversal, is increased significantly. Based on the results of the SOLIT research project, a water mist system was applied into several parts of the M30 tunnels in Madrid. As a basic principle the technical equipment and the methodology of implementation comply with the UPTUN 251 guidance, recommending minimum standards for water-based fire suppression systems in tunnels.

Jan 1, 2008

By K J. Thompson

This paper describes the work which has been undertaken at the Ohai coalfields in Southland to restore overburden heaps during past opencast mining operations, and procedures which have been adopted to ensure that restoration is achieved concurrent with present opencast mining activities. The system implemented for the treatment of wastewater from opencast mining operati6ns is also described.

Jan 1, 1981

By Black PM, Itaya T

Arc-type volcanic activity has been a major feature of the late Cenozoic geological evolution of the Pacific-Australian plate boundary in the northern New Zealand region. The timelspace distribution patterns of arc-type rocks reflect changes in the nature of the plate boundary as it has evolved. Inception of volcanism began in the north during earliest Miocene times (26 Ma) following ophiolite emplacement and during the next 10 Ma developed into a volcanic arc segment extending south to the present position of the central North Island. The northern part of the arc became extinct about 15 Ma ago, but activity continued in the central (Coromandel) part of the arc until about 5 Ma ago. In late Pliocene and Quaternary times volcanic activity has become concentrated in a northeast trending zone which is collinear with the Tonga-Kermadec Arc.

Jan 1, 1995

Acid soluble calcium is depleted in drainage sediments from hydrothermal alteration centres in the Coromandel Peninsula. The routine analysis of acid-soluble calcium on drainage samples is an economical and effective technique for outlining hydrothermal alteration centres in volcanic terrains.

Jan 1, 1979

The selection of the mining fleet can have as much of an effect on the efficiency and effectiveness of an operation as the mining method. This is not to say that inefficiencies are only attributable to inappropriate equipment selections, these aspects have many factors but are not the subject of this paper.This paper will give an overview of equipment selection processes that have been utilised to date. It will also look at the increase in application of study programs/simulations from an aspect of accuracy, as well as the importance of enabling the analysis of multiple sensitivity scenario planning. An aspect that is increasingly important in project planning with commodity market movements.Another aspect that is increasing in popularity is that of automation, what effect does this have on equipment selection? What additional aspects need to be taken into consideration when assessing Automation of equipment from the beginning of a project as well as introduction into an operating mine?Once the selection process has been finalised and equipment implemented, how do we, as an industry, 'close the loop' through analysis of estimated versus actual equipment application?

Dec 6, 2010

By P Hayes, D Fadhlurrahman

Molten slags, fluxes and salts play key roles in a wide range of the high temperature industrial process applications, including metals production, refining and recycling, metal manufacturing processes, electrochemical metal production cells, batteries, and efficient heat transfer media. Recognising the importance and significance of fundamental scientific knowledge of these systems, the International MOLTEN Conference series was established to provide a forum to bring together leading academic researchers and industrial engineers to present and discuss the latest scientific ideas and findings, and their application in their respective fields. This article presents an analysis of the research carried out in this field over time in terms of the number of journal articles, fields and slag systems studied and geographical origin of the research.

Jun 19, 2024

The Chamber of Minerals and Energy of Western Australia Inc (CME) is the peak resources sector representative body in Western Australia. The paper gives a summary of the role and objectives of the CME, including its history, structure and key program areas. Particular attention is given to the role of the CME in the Eastern Goldfields of Western Australia. The paper details the types of CME membership that are currently in existence. The paper argues that a strong and vibrant CME is vital to secure the resources sectorÆs growth and development in future years.

Jan 1, 2006

By P Hanna

Following the Busang fiasco, more detailed guidelines were appended to the latest revision of the JORC Code released in September 1999 (JORC, 1999). Although the definitions and terminology essentially remained unchanged, the additional information in the guidelines has highlighted a number of issues for consideration by geologists undertaking computer-based resource estimations. The three main issues are:Data Integrity û details such as drilling and logging techniques, sampling procedures, assay tests, site visits, data recording and aggregation methods need to be considered. Geological Interpretation û is the Competent Person applying the appropriate software interpretation to the deposit in accordance with the regional setting. Are the correct computer-based tools being applied and are they producing the desired result (without compromise) to the satisfaction of the Competent Person? Modelling Technique û the importance of the relevant experience of the Competent Person not only in regard to the geology, but also with respect to the modelling algorithms and resource calculation methods of the computer software system involved. At the end of the day, it is essential that the Competent Person undertake a reality check on the resource estimation itself. They should also check that the borehole spacing is in accordance with the level of continuity for each critical parameter (such as structure, grade, impurities, etc) for which the resources are categorised.

Jan 1, 2000

By S Reid, W Chen, T J. Donohue, A Katterfeld

The use of discrete element modelling (DEM) is widespread in the materials handling field, and is used for many applications. One of the important limitations in using DEM is the number of particles that can be modelled, with this limitation often resulting in increasing the minimum particle size in the simulation. This restriction on minimum particle size is usually accommodated in the calibration process where the parameters in the simulation are chosen in such a way as to reflect the presence of smaller sized particles, and in typical applications such as transfer chutes this is standard practice. However, in the application of vibrating screens the inclusion of the ‘fines’ is critically important due to their influence on the screening efficiency. In reality, the presence of fines reduces the screening efficiency for a number of reasons; however, the main mechanism that will be addressed in this study is the effect of adhering fines. This is where the fines adhere to the larger particles and are carried over into the lump stream. The approach for this study will be to firstly consider the relatively simple mechanical sieving process used in the determination of particle size distribution, and then this will be expanded to consider the application of vibrating screens.CITATION:Donohue, T J, Chen, W, Katterfeld, A and Reid, S, 2017. Addressing the challenges associated with the modelling of iron ore in vibrating screens, in Proceedings Iron Ore 2017, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

For years traditional optical microscopic techniques have been used successfully to carry out mineralogical studies on processing products. Essential information could be obtained by supplementing microscopic data with X-ray powder diffraction data, chemical analyses, etc. However, most of the time the mineralogists working on plant related issues, would supply qualitative information to the metallurgists, due to quantification not being possible in the available time. Since the late-80s, the use of semi-automated to automated techniques for mineral quantification has impacted positively on the use of mineralogy for optimising processing plants. Rustenburg Platinum Mines (now Anglo Platinum) were the first mining company to purchase a Qem*Sem in 1987. With the success achieved in quantifying the minerals in the concentrator streams of the Rustenburg Platinum operations, a second instrument was purchased soon after. These instruments have proven invaluable tools in understanding the flotation behaviour of the sulfide and gangue minerals in the various reefs of the Bushveld. Restrictions in the resolution of these earlier instruments, as well as the time involved in searching for and correctly identifying the fine-grained platinum-group minerals (PGM), meant that these investigations focused on the deportment of the more abundant base metal sulfides, rather than on the actual PGM. The Mineral Liberation Analyser (MLA), which became available in the late 1990s, was well suited to detect and analyse minerals occurring in trace amounts such as the PGM. Anglo Platinum was the first mining company to purchase such an instrument and now has fourteen systems operating at the AR Crown Mines site. One of the applications of these systems involves the study of feeds, concentrates and tailings from the various concentrators on a monthly basis. These routine investigations provide information on a variety of mineralogical parameters, including liberation, association, and grain size. Results are used to emphasise areas for improvement, and specifically underline those areas where improvements will have the most impact on recovery. After new or different technologies have been implemented, mineralogical characterisation of the different process streams is an essential component in the assessment of the impact of these changes on flotation performance. In addition, the knowledge is databased for future reference to draw trends across the various concentrators around the Bushveld complex, and is also used for comparative studies when plants experience high losses to tailings. Due to the success of these investigations the question was posed whether it was possible to obtain data on a daily basis, as compositing samples could hide the impact of daily events. Although the instruments currently used are suitable for a research environment, these are not ideal for mine-site implementation. For that reason Anglo Platinum, together with FEI embarked on a development program to develop a system that can be implemented on-site to measure the important mineralogical characteristics on a daily basis. Important requirements for such a system include time-to-data, ease of use and regular quality control. Highlighting some results from concentrator studies, the presentation will review the progress on the development of automated mineralogical techniques for fast, automated mineral measurements. This is an abstract only. No full paper was prepared for this abstract.

Sep 13, 2010

Old Copper Flotation Tailings Waste Reprocessing

Sep 13, 2010

Recent legislation in the environmental field gives the mining industry an opportunity to take timely action to address its image. Shifting the focus away from mining (the activity) to minerals (the resource) will enable the mining industry to stand on equal footing with other industries and will help minimise the vulnerability to political and interest groupsÆ interference.

Jan 1, 1993

The dissolution of the naturally occurring mineral zircon (ZrSiO4) is examined after ball milling it with magnesium oxide for up to 100 hours in a laboratory mill. There was little effect on the solubility for the initial two hours where size reduction of the zircon was considered to be the dominant effect. Beyond two hours the dissolution increased as a function of the square root of milling time. X-ray diffraction of the powders did not reveal the identity of the soluble phase. However, a nanocrystalline phase was present after milling and this is thought to be the soluble phase.

Jan 1, 2000

By G R. Howard, G Back

Management of information systems for data collection is essential to maintain data integrity and continuity, and manage loss control on a large world-class mine such as Telfer Gold Mine. This paper aims to describe the individual systems and protocols of geological data capture at Telfer, then focus on Quality Assurance Quality Control data as an example of loss control in practice. Loss control systems are required to provide capacity, flexibility, structure and management tools to enhance data interrogation. The data that have been collected can then provide geological, financial, environmental, and contractual information to optimise management of business best practice. Telfer Gold Mine is a wholly owned and operated subsidiary of Newcrest Mining Limited. The mine is located in a remote area of NW Western Australia, and has been operating for 20 years. Geological data have been collected at Telfer since 1973. The data include drilling, assay, geological, survey, structural and geophysical data. Data management has evolved through many systems with data stored on many different hardware and software platforms. Commencing in 1995, collation, standardisation and validation of the historic data was completed. This has resulted in the first Access based drill hole database incorporating all available drilling data. This drill hole database, now hosted in SQL Server, is the hub for all geology related data management systems. The Telfer Gold Mine Geology Department has developed a series of inter-related database systems in order to manage the core geology business issues. Databases relating to drill hole planning, drill contract management, geological logging, accounting (standard costing, forecasting, invoice reconciliation), quality control (QAQC), and environment rehabilitation have all been developed to manage loss control. Management effort to provide adequate data systems and protocols has driven the system from concept to utilisation. The improved productivity, data integrity and data analysis capabilities provided by the new database systems at Telfer have allowed for greater confidence in decision making. Systems such as the drill hole and QAQC databases, when utilised in the proper manner provide up-to-date data analysis for resource audits and contract negotiations. The loss control systems are essential to maintain confidence in data integrity and hence directly effect the future of mining at Telfer.

Jan 1, 2000

Mineralisation was identified at Gladstone Hill as far back as the late 1870's û early 1880's, shortly after the initial discovery of Martha Hill. Indeed, early recovery problems from the Martha Hill mineralisation led to the preferred development of are bodies within what is now the Union Hill Joint Venture tenement; ore bodies such as Silverton, Amaranth, Union to name a few. Work at Gladstone Hill is carried under the Union Hill Joint Venture, a 50:50 joint venture between Auag Resources Ltd - manager (a fully owned subsidiary of Otter Gold Mines Ltd) and Welcome Gold Mines Ltd (a fully owned subsidiary of the Normandy Group). The joint venture participants also operate the adjacent Martha Hill operation. Mineralisation of Gladstone Hill, as with mineralisation at the adjacent Martha Hill, has been interpreted as a low sulphidation epithermal Ag-Au system hosted within hydrothermally altered andesites of the lower Coromandel Group. Drilling in recent years has successfully identified extensive mineralisation associated with the Gladstone vein set and the more recently identified high grade Moonlight Lode. Veining ranges in character from thin stock works to broader lode-style banded chalcedonic to cherty quartz. Visible gold is rare, with mineralisation generally associated with very fine-grained pyrite, arsenopyrite and minor electrum. The potential for the Gladstone Hill area is yet to be clearly defined as drilling to date has yet to close off mineralisation both along strike and down dip. If further drilling is successful, the joint venture partners believe Gladstone Hill could contribute significantly to the economic future of current operations.

Jan 1, 1999

Mining companies in order to compete and succeed in being viable business propositions must look to the future and select mining methods which guarantee improved efficiency and productivity as well as lower costs. A mining company in adopting a method of mining must now select the equipment most compatible. To some mines compatible equipment may mean the use of drilling jumbos to replace hand held rock drills or the use of load haul dump units to replace scrapers. To other more mechanised mines compatible equipment may mean the use of raise borers and road heading machines. The right decision will be where equipment compliments method in such a way that the working environment is improved, productivity is maximised, cost if reduced and all profit opportunities are optimised. An example of such is where the use of improved mining techniques in underground operations may see cut off grades reduced. By selectively mining these lower grade orebodies, smaller operation's ore reserves improve and the capacity for continued growth is enhanced.

Jan 1, 1990

By D Frost, G Harbort, T Lipiec, N Deonarain

"The use of flotation columns has remained a contentious issue among mill operators. There are those who consider them an essential part of any mineral processing operation, while others consider them a necessary evil, which should only be installed if there is no alternative. Lastly, there are those who believe they should not be installed, no matter how great the perceived benefit.This paper provides an analysis of over 4000 installed flotation columns, contained in the Amec Foster Wheeler flotation database. Changing trends in column flotation use by type, commodity and geographical region are discussed. The effect of changing commodity prices and the China ‘phenomenon’ are reviewed. Special reference is made to the changing face of column flotation in Australia.Of note is the fact that after falling to a 20 year low in installed flotation column capacity in 2014, flotation columns during 2015 went through a resurgence in popularity. This resurgence was in direct contradiction to depressed metal prices and was driven by brownfield optimisations to reduce off-site costs, particularly in base metals. A case study is presented comparing the benefits of column flotation at high commodity prices with low commodity prices.Citation:Harbort, G, Deonarain, N, Frost, D, Lipiec, T and David, D, 2016. Changing Trends in Column Flotation Use - Their Impact for Australian Mill Operators, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 93–104 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

The role of government and the community has changed significantly over the last two decades in relation to environment protection, particularly in the mining sector. Increased community expectations have moved well ahead of regulatory requirements, and there is now a much greater appreciation generally of the concepts of ecologically sustainable development and intergenerational equity, and the gap between current practice and practices which would be in harmony with these concepts. Besides providing a `safety net' through regulations to ensure that basic environmental performance standards are met, government is now working proactively with the mining industry to encourage higher levels of environmental performance. This paper describes some initiatives between the Commonwealth government and the industry designed to achieve these higher levels of environmental performance, through programs aimed at the paradigms of best practice environmental management and continual improvement.

Jan 1, 1997

By P Maillet, A J. Crawford, S M. Eggins

TheFiji Islands are remnants of a once continuous Solomon-Vanuatu-Fiji-Tonga volcanic arc (the Vitiaz arc), located at the boundary between the Indian-Australian and Pacific plates. They record a history of: (i)                  arc volcanism the late Eocene to late Miocene, (ii)                an extensive magmatic response to arc rifting (5.5 - 3.0 Ma) during which volcanism was dominated by shoshonitic to tholeiitic basalts, and as rifting continued, (iii)               a transition from arc to intraplate volcanism.   The Hunter Ridge-Hunter Fracture Zone separates the inactive South Fiji Basin from the actively spreading North Fiji Basin, and has been considered to be a transform zone, almost parallel to the motion vector of the Australian plate. However rocks dredged during the 1993 æAlizeÆ cruise, from along the northern part of the Hunter Ridge are typical arc tholeiites, and therefore demand that subduction has occurred beneath the Hunter Ridge sometime during the last ~5 Ma. The Kadavu Island group, south westernmost Fiji, lies at the north-eastern end of the Hunter Ridge-Hunter Fracture Zone, and possibly results from oblique subduction of South Fiji Basin oceanic crust, which may have accompanied the anticlockwise rotation of Fiji during opening of the North Fiji Basin. These islands consist dominantly of 3.4 - 0.5 Ma old medium-high K andesites and dacites, with many traits typical of subduction-related volcanics, ie predominance of intermediate members (55 - 65% SiO2) no Fe enrichment, TiO2<1%, and negative Nb-Ta anomalies. These features contrast strongly with volcanics from elsewhere in Fiji around this time, where volcanic centres produced Om-like intraplate olivine basalts. The Kadavu Islands become gradually younger to the southwest, and show a significant decrease in K2O with time. The north easternmost islands (Astrolabe islands) containing the oldest rocks (~3 Ma) have shoshonitic affinities and are considered to be of similar age and composition to the youngest shoshonites found elsewhere in Fiji.

Jan 1, 1995

By J Lapwood, S Pal, M Pascoe

The devastating failure of Dam I at the Corrego do Feijao iron ore mine near Brumadinho in Brazil on 25th January 2019 left at least 270 people dead or missing. In the immediate aftermath of this event, many mining companies commenced reviews of their tailings and water storage facilities (T&WSFs), and Rio Tinto was no exception. Rio Tinto has an interest in over 250 T&WSFs across 47 sites in 13 countries as owner-operator, as managing JV partner, and through non-managed partnerships and other ownership arrangements; T&WSF experts from Rio Tinto’s Surface Mining Centre of Excellence visited the sites in order to complete Technical Risk Reviews of each facility. These reviews looked beyond the day-to-day operational aspects of T&WSF management, and the site’s compliance with local regulations and Rio Tinto’s internal D5 Standard – Management of tailings and water storage facilities, in order to provide a strategic, second line of assurance perspective. The reviews focused on design and construction; operational controls; risk control framework; and competencies and capabilities of personnel involved in the design, operation and closure of the facilities. Additional activities were carried out in parallel with these reviews, including the development of a consistent approach to dam break studies; the public disclosure of information on Rio Tinto’s tailings storage facilities and their management; and contribution to external programs such as the initiatives being co-ordinated by the International Committee on Mining and Metals. This paper provides an overview of the tailings and water storage assurance work undertaken by Rio Tinto’s Surface Mining Centre of Excellence Tailings Validation Taskforce to date; work that will continue to improve governance and assurance for all of Rio Tinto’s T&WSF.

Jul 1, 2021