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By M Salu

Ventilation control devices (VCD’s) and bulkheads are critical controls used for managing risk in underground coalmines. Following the Moura No. 2 mine explosion in 1994, the Queensland Mines Department required that the design of VCDs be based on live testing (such as in a mine testing explosion gallery) and more recently on numerical modelling using measured seal material properties. While the stipulated methods represent an idealistic solution, they are not practical to implement as solutions to daily challenges presented in underground coalmines.Not all VCD’s and bulkheads are placed in areas which have been mined to standard roadway dimensions. Operationally, VCD’s may be required to be placed close to intersections or require large dimensionally different areas (eg overcasts and pre-driven recovery road shutters) compared to the live testing or numerical modelling originally undertaken.This paper describes the various structural engineering methods utilised to account for the design of VCD’s where the operational requirements are non-standard. Siting and construction of VCD’s near the entry of cut throughs and geological structures requires additional design considerations. While VCDs constructed from a single material (eg sprayed mining plaster) are relatively straightforward to design, the addition of multiple openings (doors) or large pipes will complicate the structuralanalysis significantly.Temporary bulkheads used for the containment of grout such as for the construction of pre-driven recovery roads in coal mining have a significantly different risk profile to VCDs and should be designed accordingly. Recent failures and near-misses in such bulkheads have highlighted this issuefor the authors.The existence of an Australian Standard for Underground Mine VCDs and Bulkheads would go a long way to addressing many of the issues raised in this paper. Without a single, industry-accepted reference for VCD design, individual mines will have to continueto exercise their best judgements using whatever local expertise is available to them.

Oct 12, 2022

The Cadia Valley Operations currently hosts a large operational open pit, a large operational sublevel caving underground mine and two other underground projects at the study stage. This scenario creates an unusual situation for the evaluation and planning of a fifth major open pit project. The Cadia East Open Pit is a large gold-copper development located adjacent to the operational open pit and above one of the underground projects. A study team is conducting a comprehensive and robust analysis of the target orebody. Two key factors for this project include the existing and planned projects within the valley and the wide range of available mining methods. The aim for the study team is to present an optimal and practical case which suits the entire Cadia Valley Operation. A rigorous and robust analysis of the situation requires that each factor be properly evaluated. A modular system has been developed which allows the wide range of scenarios to be quickly and meaningfully considered. Sensitivities for each module drive the further development of that particular module. As each scenario progresses, an assessment is made evaluating its value, strategic value and practicality. In such a way, the number of scenarios is gradually reduced at each stage to produce a final short list of feasible cases. Each scenario on the shortlist is then assessed with regard to the existing operations and other projects. A qualitative and quantitative analysis is made. This ranking is used to provide the recommended case.

Jan 1, 2007

By S Meffre, S Golding, K Zaw, J McPhie, R James, S Suphananthi

The Chatree deposit is located in the central portion of Loei Fold Belt, which extends from Lao PDR in the north through centralThailand to Cambodia in the south. Epithermal gold-silver mineralisation at Chatree occurs as veins/veinlets and stockworks with minor breccia in volcaniclastic and volcano-sedimentary rocks of andesitic to basaltic andesite composition and Permo-Triassic age. This preliminary oxygen isotope study mainly focuses on vein quartz of Au-Ag bearing mineralization (Stage 2) and a few samples of late Stage 4 quartz ¦ calcite veins. Quartz from Au-Ag bearing mineralisation has oxygen isotope values ranging from 8.1 to 12.3ë with the lowest values generally occurring at the deeper level (140 m below the surface). The late barren quartz ¦ calcite veins (Stage 4) tend to have higher oxygen isotope values ranging from 11.9 to 12.0ë. The oxygen isotope composition of the Chatree ore fluids were calculated at 250¦C, 300¦C and 350¦C based on homogenisation temperatures of fluid inclusions. The calculated oxygen isotopic composition of the Chatree ore fluid ranges between -1 and 6ë that overlaps with both meteoric and magmatic compositions. This shift in oxygen isotope compositions may relate to processes such as water rock-interaction and/or mixing of meteoric and magmatic fluids. It is interesting to note that the lowest quartz oxygen isotope values are spatially more or less confined to the prominent structures in the centre of the major ore zones. These structures may have been acted as conduits for higher temperature magmatic fluids. The quartz oxygen isotope values increase outwards from the centre of the main ore zones to the margin of the pits possibly due to mixing of magmatic fluids with lower temperature meteoric water. Whole rock oxygen and hydrogen isotope studies are in progress to investigate isotopic trends in the wall rock away from the ore zone. The systematic variation of oxygen isotopes in quartz from the mineralised veins and adjacent wall rocks could potentially be used as a vector to ore. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Whitham M

Prior to exploitation, the feasibility of mining and recovering ore can usually be determined to a satisfactory level of uncertainty by the consideration of conceptual scenarios, using a range of reasonable parameter values. Such values are selected on experience, knowledge of other mining operations, and the characteristics of the particular deposit being considered. Having established such feasibility, it is usually considerably more demanding to determine what the optimum set of parameters might be. Yet many decisions taken at the feasibility stage represent commitments extending at least into the medium term.

Jan 1, 1991

By T Raynlyn, R J. Holmes, J R. Manuel, A Poliakov, L Lu

The prediction of sintering performance of iron ore fines and the possibility of targeted optimisation of specific sinter properties are very important for both the iron ore industry and related research organisations. Physical pilot-scale sinter runs require large amounts of raw materials and are expensive, so it is critical to target large test work programs with many different sintering parameters effectively. To predict values for sintering performance parameters such as tumble index (TI), low temperature reduction disintegration index (RDI) and productivity, a comprehensive database of pilot-scale sintering experimental results has been established and empirical modeling conducted. Similarly to earlier work, physical, chemical and mineralogical characteristics of the iron ores have been considered. However, in contrast to the previous work where only one textural parameter was taken into account, namely the proportion of dense haematite ore texture, the current model includes the abundances of several different textures which were combined into different textural factors corresponding to different sinter properties. Coefficients for the variables within specific regression equations can provide a better understanding of the effect of the variables on the corresponding sintering performance. The modelling results have also been used for predicting the sintering performance of mixtures that were not part of the database used for establishing the models. Comparison of experimental and modeling results for the verification test data is also reported in this paper.

Jan 1, 2009

By Guerney P. J

A suspension of finely powdered ferrosilicon in water is the dense medium used in the gravity upgrading of iron ore, diamonds and other minerals. Ferrosilicon can he lost in the plant through corrosion. The greatest corrosion losses occur when

Jan 1, 1997

Mining is an intensive resource development industry, where operations are often of relatively short duration and can result in dramatic impacts on the natural environment during the operational period and for many years post mining. An integral component of all mining operations is water û through exploration, resource definition, mine development and operation, rehabilitation and the long-term post-mining land use. Water is a basic requirement in the provision of worker amenities, in drilling, as a means of dust suppression, as a medium for washing or processing the mine product, and as an aid in establishing vegetation on post-mining landforms. Water also plays an important role in mobilising environmental contaminants and is the primary medium for the transport of contaminants off the mine or processing site into the wider environment. It is for this second reason that the mining industry considers water management as a key component of mine management. Cost-effective water management relies on planning that incorporates a total mine system approach commencing prior to exploration and continuing through to rehabilitation and decommissioning. One of the primary considerations that will provide confidence to both government and community at the time of mine closure and lease relinquishment, will be the evidence that any water originating from, or passing through, the mine site is of a quality that will not have any negative impact on the surrounding environs into the future. The role of vegetation in stabilising disturbances to a landscape is well known, as is the recognition of vegetation being a fundamental component of the water cycle through the physiological processes resulting in the transfer of water back to the atmosphere through transpiration. In terms of water management at a mine site, the two crucial issues are the æquantityÆ and æqualityÆ of water that enters a receiving æoff-leaseÆ catchment. In terms of tolerances of the receiving environment, the total load of potential contaminants becomes critical, a reduction in which can be achieved through reduced volumes of water discharged, reduced chemical and physical concentrations of contaminants in that water, and ideally, both. This paper examines the potential role of vegetation in reducing the quantity of water released from a site, and secondly considers vegetation in the role of influencing the quality of that water.

Jan 1, 2003

By Nickson NM, Lancucki CJ

X-ray diffraction and differential thermal methodshave been used to determine the mineralogy of some clays used by the heavy clay industry in the Adelaide area. A detailed analysis has been made of the mineralogy and. particle size distribution of eighteen samples from beds' in two pits in~the Recent seaiinents in the Adelaide plains, of six white clays.: developed from the weathering of the Adelaide series of `sediments and, of ,four -Recent alluvial clays from a pit in the Mount Lofty ranges south of Adelaide. Structural clay products 'in the Adelaide area are manufactured from mixtures of these clays:, so the mineralogy and particle size distribution have been determined of eighteen clay mixtures used to make red bricks, cream bricks,. facing bricks, pipes and tiles. Knowledge of this mineralogy is important in understanding the ceramic behaviour of the clays.

Jan 1, 1963

By D Kent, R Paine

"Automated mining systems are increasingly being seen as a key requirement for a productive mining operation in the future. The importance of an integrated communication network infrastructure to support such systems is growing.This paper outlines the introduction of automated mining systems in large conventional mines as well as their growing role in block cave mines currently operating or being developed. The paper will then focus on a case study of how the communication infrastructure is fundamental to the operation of such systems and explain why the resultant communication networks require much more than just increased bandwidth (data capacity) to properly support the automation system within the overall mine operation.Mining operations already embarking down this road are discovering that the required network must be based on a true enterprise level architecture to not only enable the mine’s current plans for remote and automated mining, but also provide a scalable and integrated platform for future developments and requirements. The emerging issues for the communication network to truly support automation systems include: increased complexities of operating and maintaining multiple networks integration issues with disparate systems problems with reporting particularly as demands for corporate reporting and compatibility with enterprise systems become the norm ongoing management challenges, which will only increase with the proliferation of new technologies.The paper will explore how certain mining operations are addressing this by adopting a long-term strategy for automation deployment, which includes laying the necessary foundation architecture to meet their current requirements, while supporting their future visions for the fully automated mine.CITATION:Paine, R and Kent, D, 2014. Developing the foundation communication infrastructure to support remote and automated mining initiatives in underground mines, in Proceedings 12th AusIMM Underground Operators’ Conference 2014, pp 151–158 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 24, 2014

By D Maldonado

BlueScope Steel’s Port Kembla sinter machine underwent a major upgrade during mid-2009. The mixing and rolling drum (MRD) was thoroughly cleaned during the upgrade. Space factor measurements taken in October 2009 showed that the drum was operating in the cataract regime in the dry mixing section and the cascading regime in the rolling section, which is optimal for granulation. Sampling carried out during an entry into the MRD showed that both the Sauter mean diameter and the predicted bed voidage increase rapidly during wetting, and then decrease in the wet mixing section. In the rolling section, the granule properties remained constant untilthe drum discharge. Frozen particle analysis, using liquid nitrogen as the quenching agent, were carried out on material collected from the MRD discharge. The results, expressed as a Granulation Index, showed there had been a significant improvement in the granulating performance of the MRD following the upgrade. The plant studies were also complemented with laboratory scale experiments which aimed to optimise the granulation process. The effect of burnt lime on green feed permeability was quantifi ed using the laboratory scale drum at different moisture contents. A significant increase in permeability was apparent once the burnt lime dosing rates doubled from 1.1 - 2.2 per cent w/w (feed basis). The capacity of the burnt lime system at the sinter machine will be increased in order to benefi t from the expected higher permeability, permeability, which will enable the machine to sinter at deeper bed heights.

Jul 11, 2011

Since its commercial in Australia at Broken Hill in the early part of the 20th century, the flotation process has grown to become the single most important minerals separation method available to mineral processing engineers. Statistics on flotation are impressive both in terms of growth of tonnages treated and in terms of the variety of separations accomplished. Because of the steady decline in the grade of ores and because many of the ores remaining are finely disseminated mixtures of minerals (many of them in a highly oxidized state) mineral processing scientists and engineers are now con- fronted with the problem of improving and modifying conventional flotation techniques so as to be able to effic- iently process these more refractory types of-ores. The flotation process did not come into being as the result of an intensive fundamental research effort but, in a similar way to so many other methods used in the processing of raw materials, it was developed over the years by the continued application of empirical methods. As a result, most of the basic research in this field has long been concerned with the problem of explaining why the existing process works so well. We are now at the stage where any further substan- tial extension of the flotation process will demand a more profound understanding of its fundamental principles. Current knowledge of flotation fundamentals is still far from the stage where processes can be designed, optimized, and controlled from first principles. The extensive

Jan 1, 1984

By A van As

This paper serves to outline the circumstances and causes of the air-blast that occurred at Northparkes Mines in November 1999. It describes the design of the mine, the geotechnical issues surrounding cave propagation and the cave monitoring systems that were in place prior to the event. A short description of the air-blast that followed a sudden collapse is given. Details of the risk assessment process that evolved during the rectification process are provided with their subsequent modification to form the core of a major hazard monitoring process. The system is in line with the recommendations given by the Coroner resulting from the inquest into the deaths of the four people who lost their lives during the air-blast.

Jan 1, 2005

By C P. C David, J P. T Domingo

Addressing nutrient deficiency, among other factors, is vital to the growth and establishment of plants in mine spoils and tailings ponds. Although several organic amendments are available for this purpose, it is important to determine the appropriate ameliorant for the selected plant species. This research examined the effect of different amendments on the growth and ground cover of Centrosema molle, Calopogonium mucunoides and Sorghum spp. in copper/gold tailings. Plant growth and ground cover drastically increased with the application of organic ameliorants, especially manure. Among the three plants, Calopogonium exhibited the best growth and has shown its capability to establish a dense ground cover even in unamended tailings. Results suggest that the plant species and the ameliorants used in this study could be effective in a low-input approach to mine rehabilitation.CITATION:Domingo, J P T and David, C P C, 2014. Legume and grass revegetation of mine tailings, in Proceedings Life-of-Mine 2014 , pp 525–534 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

This paper outlines the thermodynamic and mass balance principles which affect the distribution of cobalt between matte and slag during the pyrometallurgical treatment of nickel - copper sulphides and considers the implications with regard to maximising the recovery of cobalt from the smelting and converting circuit.

Jan 1, 1992

The Quiruvilca district, located 80 km east of Trujillo in north central Peru (Fig. 1), has produced over eight million tons of Cu-Pb- Zn-Ag ore from approximately 60 veins since 1789. "Quiruvilca means "sacred tooth" in Quechua, the lingua franca of the Incas. The expression refers to a prominent volcanic neck exposed several kilometers northeast of the district. The district covers an area of approx- imately 24 km2. The mines occupy the eastern quarter; workings underlie 6.7 km2 with a developed vertical range of 280 m. All pres- ently operating workings are owned by Corpora- cion Minera Nor Peru S.A., a subsidiary of ASARCO Incorporated. The oldest rocks in the area are Lower Cretaceous clastic sedimentary rocks exposed 7 km to the east. Lithologies include sand- stone, siltstone, shale, coal seams, and carbonates (Cossio, 1964). These rocks were folded and affected by regional low-grade metamorphism during the early Tertiary, 40-65 m.y. (Hollister, 1977).

Jan 1, 1987

By T Peglas, A de Aboitiz

The Queensland Government, via the special purpose company vehicle û City North Infrastructure Pty Ltd û is currently developing BrisbaneÆs Airport Link underground toll road and Northern Busway (Windsor to Kedron).Airport Link is a predominantly underground toll road planned between BrisbaneÆs northern suburbs, the airport and the Brisbane Central Business District (CBD) frame. The Northern Busway forms part of BrisbaneÆs expanding busway network, sections of which will be jointly delivered with Airport Link. Airport Link will connect the North-South Bypass Tunnel, Inner City Bypass and local road network at Bowen Hills to the northern arterials of Gympie Road and Stafford Road at Kedron and Sandgate Road and the East-West Arterial in the cityÆs north-east. The Northern Busway is a two-lane, two-way bus-only roadway proposed to connect the existing Inner Northern Busway at Herston with Windsor, Lutwyche, Kedron, Chermside, Aspley and Bracken Ridge. Airport Link and Northern Busway (Windsor to Kedron) is one of the largest infrastructure projects planned in the first phase of the State GovernmentÆs South East Queensland Infrastructure Plan and Program. The paper will provide an overview of the projects, including a discussion on the technical and environmental aspects as well as the procurement of the Airport Link as a public private partnership.

Jan 1, 2008

By R Jones

OneSteel Whyalla’s grate-kiln-cooler pelletising plant was commissioned in 1968 processing haematite feed from the local South Middleback Ranges mining area. The existence of a magnetite resource beneath the haematite ore at Iron Duke had been known for some time. In 2004, a decision was made to covert the primary iron source for the Whyalla steelworks from haematite to magnetite – known as project magnet. The intent of the project was to convert the feed to the steelworks from haematite to magnetite and to free up the remaining haematite resource for export. The pelletising plant was cut over to a magnetite feed in 2007.The thermochemical differences of magnetite compared to haematite are threefold:1. the introduction of an exothermic reaction during conversion of magnetite to haematite,2. the absence of bound water which existed within the haematite, and3. lower gangue content requiring lower fluxing levels and therefore lower calcination energy demand.The combination of these differences results in a significantly different induration requirement for magnetite as compared to haematite. The change therefore required extensive research and test work to design modifications to the furnace and to ensure appropriate risk mitigation for the Whyalla steelworks.Preliminary pot-grate test work was performed to define the pellet chemistry and confirm the suitability of the magnetite to produce pellets suitable for the OneSteel blast furnace. A heating curve was developed by use of computer-based heat and mass balance modelling. Extensive pilot scale grate-kiln-cooler test work was then performed to confirm the heating curve and to verify and fine-tune the pellet properties. Computation fluid dynamics was used to design the physical changes to the furnace required to achieve the proposed heating curve.Following installation of an additional preheat zone, including a wall and dilution air fans, into the preheating furnace, and installation of an additional wall into the cooler, the modified furnace was commissioning in December 2007. The plant performed as expected during commissioning with the actual heating curve matching the proposed curve and the produced pellets within blast furnace specifications.

Jul 11, 2011

By B Chapman, R Nievergelt, J Hill

A major component of Sydney’s new South West Rail Link project is the Hume Highway Underpass (HHU), an 80 m long twin track mined tunnel excavated at a depth of just 5 m below the pavement of the Hume Highway; one of Australia’s busiest road corridors.In order to ensure a safe and efficient construction of the underpass without disruption to the Hume Highway traffic, design of the HHU required specific focus on the prediction and control of ground movements. This paper describes the design and construction solutions adopted in response to these challenging constraints. The paper also provides discussion on the observed behaviour of the underpass during construction and the results of a back analysis that was undertaken during construction.CITATION:Hill, J, Nievergelt, R and Chapman, B, 2014. Design and construction of Sydney’s South West Rail Link Hume Highway Underpass, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 375–386 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Morland R

In the course of an exploration program aimed at increasing Pasminco Mining's ore reserves, an electromagnetic survey down one of the underground drillholes at the North Mine, Broken Hill, recorded a broad and persistent response. This paper demonstrates that the anomaly was not due to any geological feature, but rather was caused by 'self-response' of the sensing probe. The observed results are due to the surveyed hole lying within a resistive environment and having distinct, but not unusual, changes in dip.This phenomenon has not been widely reported and we believe that there are likely to be similar cases in company records where very genuine looking responses are due to self-response rather than sulphides. These false anomalies can be recognised by correlating the observed data with the calculated down-hole component of the transmitting loop's primary field.

Jan 1, 1994

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