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By Manca PP, Lassandro R, Caranassios A, Massacci G, Ciccu R

The paper discusses the state of the progress reached in the development of the diamond wire tool for cutting hard rocks. To the advances of this relatively new technology a substantial contribution has been provided by the research being carried out at the University of Cagliari on samples of granite rocks from different Sardinian stone quarries. On the basis of field experiments and laboratory test data, the mechanism of diamond wire cutting has been assessed. In particular the influence of the rock features and operational variables on tool performance (cutting rate and bead wear) has been Elucidated.

Jan 1, 1992

The control system of a mine winder or other variable speed drive has many component parts that must work together to provide the required functional performance of the machine, together with comprehensive safety features, reliability, maintainability, user-friendliness and efficiency. Modern winders use digital control technology extensively and hence software design is a major part of the overall system. It is not practical to simulate an entire mine winder in a single computer model because of the sheer mathematical complexity of the behaviour of many of the components. However, most component parts can be simulated quite easily, and related parts of the control system software can be simulated. Such simulations allow control software algorithms to be developed and tested in isolation from the real plant. Tests can be performed on the model without fear of injury to personnel or damage to the valuable plant. For example, speed regulator control algorithms and stability settings can be adjusted to and beyond the limits of stable operation, and near optimum settings can be found. This is particularly important, for example, when designing closed loop controls for emergency brake systems. Obviously, care must be taken to ensure that the computer model of the plant is realistic and takes into account as many non-linear features of the real plant as possible. Pure mathematical analysis of some systems is very difficult to perform when non-linear plant behaviour is involved. This paper shares a number of practical simulation experiences performed using commercially available software such as Matlab and Simulink to simulate various parts of the control system of a mine winder or other variable speed drive. Demonstrations of the operation of several different computer models are shown during the presentation of the paper.

Jan 1, 2005

By A K. Bhatnagar, S Saha, P Dixit, A K. Mukherjee, P Patra

TATA Steel’s R&D Division at Jamshedpur has developed a slime beneficiation process to recover iron values from iron ore slime. This process recovers iron ore concentrate containing 2.2 per cent alumina from a feed containing 7–10 per cent alumina. The reject generated from beneficiation of iron ore slime is treated as waste as the iron content in the reject is below 45 per cent. Effective utilisation of this waste is required for making the iron ore slime beneficiation process a zero-waste technology. In this connection several studies were made towards utilisation of slime waste. One of these studies revealed that slime waste can be used as a soil conditioner. Slime waste contains particles of size less than 10 micron and when these particles are mixed with soil in definite proportions, the porosity and the permeability of the mixture goes down. As a result, the water holding capacity (WHC) improves. This concept was evaluated through a series of tests at greenhouse level to optimise the soil to slime ratio. Finally, a pilot scale field trial was carried out over a period of three months using paddy rice as the crop. Three separate plots with compositions of: soil + organic matter comprising Farmyard Manure (FYM), (ii) soil and slime waste (2:1) + organic matter (FYM), and (iii) soil and slime waste (2:1) + organic matter (FYM) + Nitrogen, Phosphorus and Potassium (NPK) fertiliser were used for the pilot trial. The results showed a 20 per cent increase in the productivity of paddy rice for plot (ii) as compared to plot (i). This was due to the beneficial effect of slime waste in the soil. The addition of inorganic fertiliser such as NPK in the ratio of (4:2:1) further enhanced the productivity of paddy rice.

Sep 18, 2023

The words ""Uncertainty"" and ""Risk"" pervade every discussion about mining exploration and investment. Perhaps these terms are subjectively understood by industry professionals, but objective portrayal of these concepts outside the industry is a woefully undeveloped science. This paper addresses current industry understanding and practice regarding quantitative risk assessment techniques, and provides examples of the application of three of these techniques. Probabilistic techniques for financial risk assessment are valuable adjuncts to conventional financial analysis, and address a range of issues not assessable by any other means. The value of whole-of-project probabilistic risk assessment is currently debatable for decision-making purposes, but is seen as important as a mechanism to focus attention to the critical issues that ultimately impact on project success. The dissection of project capital into risk and non-risk components provides valuable insights into risk characteristics not readily quantifiable in any other way. This technique also provides a framework for more objective ""what if?"" scenario evaluation and for the capital structure of resource projects. Finally, mechanisms for the valuation of undeveloped reserves are examined, and guidelines suggested. The importance of reliability in production cost estimates is highlighted and the impact of early development on reserve valuations is discussed. The importance of economics throughout all stages of the evaluation process is fundamental.

Jan 1, 1994

By A P. Wibowo

Indonesia holds a significant role in the utilisation of coal resources in the world. Although the number of Indonesian coal resources and reserves do not fall into the world’s top ten, according to 2009 statistics, Indonesia is the seventh largest producer of coal with a production of 256 Mt. More than 80 per cent of this amount is sold in the export market, making Indonesia the world’s second largest coal exporter. Most of the exported coal from Indonesia is used to fulfil the needs of the Pacific market, such as Japan, Taiwan, China, among others. It is also possible to reach the Atlantic market.Along with Indonesia’s development program, until 2025 the Indonesian government has adopted a National Energy Policy that aims to reduce the role of petroleum in electricity generation and replacing it with coal. As a follow-up of the policy, since 2009 PT PLN, the state electricity company has built steam power plants throughout Indonesia as an implementation of the first stage of the Electrical Acceleration Project with a capacity of 10 000 MW. Moving forward, in 2011 PT PLN will also build the second stage of the project with a capacity of 10 000 MW. As a result of the program, the domestic need for coal is expected to increase as much as 44.8 Mt.With the increase in domestic need and decrease in the number of reserves, the Indonesian government has adopted policies to secure the domestic coal supply. A policy that may potentially be adopted by the government is the limiting of coal production, seeing the high rate of increase in Indonesian coal production. The adoption of such a policy will change the distribution map of coal in the Pacific market. Thus, this paper will evaluate the change of coal distribution patterns in the Pacific market along with the increase in Indonesian domestic needs and Indonesian adoption of policies regarding the securing of coal supplies.

Nov 22, 2011

By F Butler, G E. Batley, A C. Hogan, A R. Butler

The ANZECC/ARMCANZ (2000) Water Quality Guidelines (the Guidelines) are the primary reference used in Australia and New Zealand for managing and regulating water quality. For most mining operations in Queensland, the environmental authority (EA – licence) incorporates the national default guideline values (GVs) for ecosystem protection as trigger levels (TLs). Exceedances of TLs ‘trigger’ further investigation and reporting. A review of the surface water compliance history at a metalliferous mine in North West Queensland identified minor exceedances of the cobalt GV as a common trigger for investigation and compliance reporting.The reliability of GVs is dependent on the availability and quality of ecotoxicology data for the relevant contaminant. The current national default GV for cobalt of 1.4 µg/L is classified as a low reliability GV due to the lack of available data at the time it was derived (ANZECC/ARMCANZ, 2000).The Guidelines are presently being revised and the toxicant GVs will be available as a set of web-based values and associated technical briefs. The new platform will enable the timely revision of existing GVs and inclusion of GVs for additional toxicants. Cobalt was considered a priority toxicant for the Guidelines’ revision, but was not included in the revision process.A preliminary review of the international literature indicated that at least 15 additional chronic cobalt toxicity studies had been published since 2000, sufficient to derive a high reliability cobalt GV using the protocols developed for the revision of the Guidelines (Batley et al, 2014; Warne et al, 2015). This presented an opportunity to improve environmental management by increasing the reliability of the performance measure.CITATION:Hogan, A C, Butler, A R, Butler, F and Batley, G E, 2016. Derivation of high reliability water quality guideline values for cobalt in freshwaters – improving water quality guidelines for better water quality compliance management in mining, in Proceedings Life-of-Mine 2016 Conference , pp 205–208 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Hocking G

For some underground structures, the use of the plane strain assumption in stress analyses may not be justified. The finite element method and photoelasticity have been used to obtain complete 3-D solutions, but, for various reasons, neither method has found universal use. The boundary integral equation method (B.I.E.M.) can be more efficient and economical than the finite element method for 3-D problems involving large volume to surface area ratios. A B.I.E.M. program developed for calculating stresses and deformations in infinite elastic media has been used to determine the 3-D distributions of stress around T- and Y- junctions of circular tunnels in stress fields in which the ratios of horizontal to vertical stress are 0, 0.33, 1.0 and 2.0. For the T- junction considered,stress concentrations at the intersection are approximately twice the plane strain values. Except where horizontal field stresses are high, the stresses in both tunnels approximate the plane strain values at about two tunnel diameters from the point of intersection of the tunnel centre lines. The stresses in the two branches reach those for the corresponding plane strain, two parallel tunnel case two diameters from the point of intersection of thq inner tunnel walls. Very high stress concentra- tions occur in the pillar of rock between the inner tunnel walls near the point of intersection.

Jan 1, 1976

By P J. Sack, L V Danyushevsky

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Regional-scale exploration for sediment-hosted gold deposits is hampered by the challenge of evaluating the fertility of ancient sedimentary sequences that host these deposits. Recent developments in laser ablation inductively coupled plasma mass spectrometry allow for the evaluation of the gold fertility of sedimentary sequences using chemistry of early-formed sedimentary pyrite. We present a case study from the Selwyn basin area of Yukon, Canada, where significant sediment-hosted gold exploration has been ongoing for the last five years. Data from sedimentary pyrite in some Neoproterozoic shales are anomalous in Au and As compared to a global data set of unmineralised sedimentary pyrite. If at least some of the gold and associated trace elements in sediment-hosted gold deposits are derived from recrystallisation of early sedimentary pyrite, it follows that strata containing anomalous sedimentary pyrite should be more prospective. Based on this premise, our data clearly show that Yusezyu Formation Neoproterozoic shales in the Selwyn basin area of Yukon are a fertile source rock for sediment-hosted gold deposits, while pyrite from Nadaleen formation shales are strongly anomalous in Hg and Tl, but not Au. We suggest that the area warrants continued exploration for sediment-hosted gold.CITATION:Sack, P J, Gregory, D D, Large, R R and Danyushevsky, L V, 2015. Using sedimentary pyrite chemistry to inform regional exploration for sediment-hosted gold deposits – a gold fertility case study from the Selwyn basin area, Yukon , in Proceedings PACRIM 2015 Congress, pp 69–76 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

With the theme of û æUnderground Ore Handling SystemÆ, Kopanang Mine completed an extensive project on a specific system with technologies for the handling of ore from a dedicated drawpoint to the shaft system. The intended rail haulage tramming system had to be capable of handling the shaft design and Life of Mine (LOM) requirements. Kopanang is an AngloGold Ashanti gold mine situated in the province of the Free State in South Africa. In the Sotho language the name æKopanangÆ means to come together as a team. ItÆs an appropriate name given that 25 companies worked on this project. The future focus at Kopanang is to establish four mining levels between 3 to 4 km south-west of the shaft and two mining levels to the west. The mine has an expected life of almost 20 years and capital was approved in order to access this reserve to establish the infrastructure to handle the ore, hence this exclusive rail haulage tramming system of close to R40 million (SA rands), which took three years to construct. Apart from the fact that this system had to be capable of handling 6500 t per shift at a depth of over 2 km over a length of 3.2 km, some of the major considering factors were: safety, economic factors with improved labour productivity, efficiency and reliability, risk termination, and ergonomics. The system comprises two 20 t locomotives operating in a double header configuration from a dedicated draw point to a dedicated tip area for the reef and waste ore. With the objective of handling high speed and high capacity, this 200 t payload train is capable of running at 35 km/h powered from a 500 volt ac overhead line. Each loco consists of two 90 kW dc motors with ac/dc power conversion on the locomotive. For the system to operate at this speed, the rail system is constructed with Class 1 rails over the entire hauling distance. The tipping mechanism is unique and the span of 11 hoppers each with a load of close to 20 t is capable of tipping the pay load of 200 t in about 20 seconds hands free.

Jan 1, 2005

By Munive L

As a result of commissioning No.5 B F, 2670m3 inner volume, in March 1972, the largest B F in Australia; new expertise in maintenance, furnace operating practices and design have been obtained. This experience has also been extended to the other furnaces. A series of operating problems were con- fronted; all parts of the furnace, including the hearth side walls and bottom,were adversely affected. In December 1977, serious hearth wall wear was detected at No.5 B F, and a potential hearth breakout was averted. Hearth wear in No.4 B F was discovered in March 1979, and emer- gency underhearth cooling was installed to reverse an extremely advanced hearth bottom erosion. Hearth behaviour of No.5 B F oampaign 1972-1978 and`No.4 B F campaign commencing 1972, has been studied and discussions on the causes, effects and measures undertaken to protect the hearths are presented in this paper.

Jan 1, 1981

By T Purvis, J Calverd, A-K Greve

The Ernest Henry Mining (EHM) underground mine is situated adjacent to the Great Artesian Basin in North Queensland and within a fracture zone. Underground development commenced in February 2008 and has extended to approximately 1000 vertical metres below the surface.Groundwater has been encountered in numerous locations throughout the mine, predominantly on the eastern side of the orebody and often related to fault structures. Most of the groundwater encountered has been managed with conventional pumping systems; however, on occasions large water inflows have been encountered, which have had a significant impact on the planned development of the mine. Some of the intersections encountered had the potential to compromise the mine from a combination of high temperature (over 45°C), high pressure (3500 kPa) and high flows (50–100 L/s).This paper describes three case studies where significant water inflows were encountered and then controlled by the injection of cementitious grout into the rock mass. The case studies are the 1650 mid-shaft heading, the 1325 shaft access decline and the 1625 to 1475 fresh air rise (FAR) raise bore. Each case study includes a brief description of the event that occurred and the grouting equipment and techniques developed to enable mining to continue.The paper also describes the development of a hydrogeological map of the mine, the probe-hole regime used for high-risk headings and the required processes and systems to inject both cementitious grouts and polyurethane resin into the rock mass.CITATION:Purvis, T, Calverd, J and Greve, A-K, 2014. Management of high-pressure groundwater in underground development at Ernest Henry Mine, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 217–226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By G H. Park, Y J. Jun, J H. Park

The carbon solubility of the CaO-Al2O3-FeO-SiO2-MgO slag, the main system formed in the Ruhrstahl-Heraeus (RH) vacuum degasser, was measured at 1873 K to understand the effect of slag compositions on the carbon contamination in the ultra-low carbon (ULC) steels. The stable form of carbon was demonstrated to be carbonate by plotting the log [(wt%C)/aC] ratio against the log p(O2) which ranged -11 < log p(O2,atm) < -9. The carbon solubility of the CaO-Al2O3-FeO-SiO2-MgO slag can be estimated using thermodynamic model. The distribution ratio of carbon increased with increasing concentration of FeO due to the FeO reduction reaction and increased basicity of slag. The carbonate capacity of the CaO-Al2O3-FeO-SiO2-MgO slag can be expressed as a linear function of the activity of lime and the optical basicity.

Jun 19, 2024

By N Donnellan

The Palaeoproterozoic Warramunga Formation is notable as the host to the enigmatic, so-called &apos;Tennant Creek style&apos; mineralisation. These polymetallic (but mainly Au-Cu-Bi) ore deposits typically have a close spatial association with massive ironstone bodies, and frequently also with banded ironstone, known locally as &apos;haematite shale&apos;. The Warramunga Formation is a polydeformed, turbiditic succession. Partial, or complete Bouma sequences variously comprising lithic arenite, wacke, siltstone, and mudstone constitute a classic flysch sequence deposited as a proximal (sandstone lithofacies) to distal (siltstone lithofacies) fan association. The Warramunga Formation has a substantial component of volcanic detritus and has generally been attributed to an essentially contemporaneous volcanic provenance. However, lithostratigraphic revision (Donnellan, Hussey and Morrison, in press) apparently precludes outcropping volcanic rocks of the Tennant Creek Block, or indeed Inlier, as the source of detritus. Warramunga Formation geochemistry indicates rapid derivation from a fractionated, predominately felsic igneous source (Palaeoproterozoic upper crust) with a minimum of chemical weathering; together with an admixture of mafic material. Warramunga Formation geochemistry cannot, however, be reconciled with that of the Bemborough Formation, which is here taken to be representative of Flynn Subgroup felsic volcanic rocks. Similarly, the Warramunga Formation is geochemically distinct from Flynn Subgroup sedimentary rocks. Geochemistry of the banded ironstone is consistent with its interpretation as Dine-grained turbidites.

Jan 1, 1994

By Dudgeon RN, Houston ML

When the original Mount Gunson joint venture,between CSR Limited and United Uranium N.L. ceased operations in December 1971, an intensive exploration campaign was launched to prospect for more ore in the Mount Gunson region. This campaign resulted in the dis- covery&apos;of the Cattle Grid copper deposit. A comprehensive sampling pro- gramme including the sinking of over 200 diamond drill holes and two vertical shafts,proved the existence of 4.6 million tonnes of ore, at a mean grade of 2.4% Cu,calculated at 1.00% Cu cutoff.

Jan 1, 1975

The procedure used for Truck Maintenance is described systematically in this paper. Emphasis is given to manpower required, work facilities, daily maintenance and oil sampling procedure. Scheduled Preventative Maintenance Service, Electrical Service, Component Change, Truck Overhaul and Outside Contractors are also discussed. The system used, achieves the required results with an average haul truck availability in 1981 of 87.9 per cent. INTRODUCTION Situated on the Island of Bougainville, in Papua New Guinea, the Bougainville Copper mine nestles in a valley near the crest of the Crown Prince Range, between 600 m and 980 m above sea level. The mine is serviced by two towns, Arawa - an open town on the Coast and Panguna at the Mine Site. Currently Bougainville Copper operates an open pit mine removing an average of 198 000 dry metric tonnes of material per day (115 000 tonnes ore and 83 000 tonnes of waste) with a fleet of electric shovels and 154 tonne electric haul trucks.

Jan 1, 1982

By R M. Stephenson

Large diameter raise boring is a common raise excavation method in the Australian mining industry. Geotechnical investigations were conducted on several large diameter raise bore projects at Gwalia Mine to assess the potential for instability and potential back-reaming problems. A thorough geotechnical analysis and subsequent back-analysis was conducted on a vent raise excavated at 5.5 m diameter and 810 m length.The geotechnical investigation for the vent raise included collection of data from an acoustic televiewer survey that was conducted on the pilot hole. The survey results provided structural data and an insight into the effects of stress on the pilot hole. Structural analysis was conducted using a combination of information obtained from the acoustic televiewer survey and geotechnical logs of the diamond drill core drilled close to the site.Further information was collected from drillers’ plods from pilot hole drilling and back-reaming to conduct a back-analysis of the completed shaft, and this was compared with the structural analysis.The key finding from this review was that the acoustic televiewer survey of the pilot hole accurately identified locations with blocky conditions. This is an important supplement to the information available from the main geotechnical investigation hole, as this was offset from the shaft location over most of its path.CITATION:Stephenson, R M and Sandy, M P, 2014. Structural analysis of acoustic televiewer logs for large diameter raise bored shafts, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 89–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

The brown coal deposits of the Latrobe Valley are ideal for open cut mining and this method has been used since the start of coal winning in 1894. Operations at the main Yall9urn open cut commenced in 1922, but after a few years the main excavators were replaced by German continuous excavators and subsequent developments of Yallourn and the newer Morwell open cut have been based on this type of plant. The reasons for preferring continuous to intermittent excavators in the Latrobe Valley are indicated in this paper.Under the pressure of post-war conditions, and from their long experience and ability, German engineers have recently made substantial improvements in their continuous excavators and these developments have been enhanced by some American innovations. These changes have extended the economic limits of open cut mining and also serve to emphasize the close inter-relation between the nature of coal and overburden deposits, excavator design and methods of operation.As an aid to descriRing recent excavator developments, this interdependence is demonstrated by means of diagrams which show typical methods of operations, together with examples of actual machines using these methods. The types of excavator dealt with are mainly those in use at, or destined for Yallourn or Morwell open cuts, together with additional types used in U.S.A. and Western Europe. For completeness, and also because they will continue in service at Yallourn and Morwell for some years, rail-mounted dredgers have been included in this paper even though in Europe they are now regarded as obsolescent.Explanations are given of how the intrinsic qualities of Latrobe Valley brown coal and overburden have sometimes prevented overseas plants from operating with the full efficiencies and/or in the methods visualized by the manufacturer, and references are made to the modifications and investigations being undertaken to overcome these problems.A compresensive bibliography is given. Dates shown on illustrations are not commissioning dates of the plant concerned, but the year when photographed.

Jan 1, 1960

By Browner R, Kyle J

The adsorption of gold cyanide by the weak base ion exchange resins, PAZ-4¦ and Duolite A-7C, the neutral polymeric adsorbent, Amberlite XAD7¦, and the strong base resins, PAZ-8~a and IRA-400 have been studied in both low and high salinity waters, and their performance compared with activated carbon. A systematic study has also been made of the effect of different ions (Na+, Cat+, Mgt+, Cl&apos;, SO4) ) on the gold adsorption capacity and kinetics of these resins. The results indicate that, contrary to popular belief, the ion exchange resin, can perform effectively in highly saline environments. The performance of the neutral polymeric adsorbent im- proves with increasing salinity but cannot match the performance of the ion-exchange resins.

Jan 1, 1991

South Africa is the world&apos;s largest producer of gold. The survival of its gold mining industry is dependent, to a large extent, on the successful implementation of new mining technology which reduces the operating costs. Gold mines of the country have a record of a high operational cost per tonne of rock excavated. The geology of the gold-bearing rock, in addition to the mining depth and the gold recoverable grade, profoundly affect the profitability of the industry. Among the other mining operations, drilling and blasting take a fair share of the mining cost. It is therefore proper to implement a dynamic approach of technological review aimed at combating the escalation of mining costs. Over the years, the industry has moved away from labour intensive activities. Mechanised operations are introduced where possible. Management techniques are oriented more towards better utilisation of human resources and machinery so as to enhance productivity in the stopes. This paper addresses the issue with particular reference to blasting operations in the stopes of deep gold mines. It reviews the conventional drilling and blasting techniques. It outlines some innovative changes brought about in the course of recent years with the aim of optimising productivity and the stope efficiency in particular. It focusses on the peculiarities of the blasting technology in deep mines. It discusses the issue of interaction between the high stress fields underground and the blasting generated stresses on rock fragmentation, as well as their impact on the remaining excavations. It anticipates the concept of the new technology of selective blasting in stoping. Finally it puts forward the crucial role played by management of the human factor underground.

Jan 1, 1995

Author Biography William Poole was born in Sydney, NSW in August 1868. He was educated at Sydney Grammar School. William spent two and a half years as a cadet in the Railway Construction Branch of the NSW Department of Public Works doing office and field work. He then undertook a civil engineering course at Sydney University. Following this he was employed for six years as assistant and resident engineer at the Water Conservation Branch, NSW and was in responsible charge of various field operations, surveys, river gaugings and works of constructions including a large timber weir and also a concrete weir on the Macquarie River, NSW. He then undertook a mining and metallurgical course at Sydney University and became a graduate (BE) with honours in civil engineering, mining engineering and metallurgy. He then spent four and a half years with BHP Co, one and a half years at Broken Hill in the mining and concentration works and three years at the smelting works in Port Pirie, SA, in the latter case he was metallurgist and night superintendent and during that time had responsibility and control at night of the blast furnaces and, during the last 15 months, of the whole of these large works. The author left the Port Pirie, SA works to assume the position of Director of the State School of Mines at Charters Towers and had responsible control of the establishment and also lectured in mining, surveying and structure. William Poole was honoured to hold membership in the following organisations: Assoc M Inst C E, L S of NSW, M Aus Inst M M, Assoc Inst M & M (London).

Jan 1, 2006