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By Brien R. J, O&apos

Faster and more efficient methods of producing and refining iron and steel are imposing severe conditions on the refractory materials used to contain these metals in the molten state. In order to provide refractory linings which will give the desired service life and maintain unit availability at an economical level, it is necessary to appreciate the aggressive environment in which the refractories operate and determine the reaction mechanisms by which the refractories are destroyed. Only by such studies can the most suitable refractory or refractory combination for a particular unit be selected. Examples of refractories selection and reaction mechanisms are discussed for blast furnaces, BOS vessels, AOD vessels, steel ladles, vacuum degassing units and continuous casting.

Jan 1, 1976

Access roads for haulage, construction or maintenance purposes are discussed with particular attention being given to the un- sealed "all weather" form of construction for Off-Highway applications. The service conditions experienced by the surfaces used in these roads is examined. These conditions are discussed in terms of the conventional engineering properties used for natural gravel material selection. Experience gained during the construction of a pipeline access track is used to illustratE material selection guidelines based on geological input and an understanding of good construction practices. TMITDnIll IrTT Ohl In many Australian situations off-highway haulage by wheel or track supported vehicles is carried on unsealed, gravel roads. Although the unsealed gravel road is the back-bone of the rural road network in Australia, in general, traffic loadings are relatively low compared to the off-highway unsealed haulage road. The cost of the haulage/access road construction component is one important factor in project planning which needs careful consideration. It is no longer acceptable that the initial rough exploration track be gradually upgraded so that it will eventually carry construction and maintenance traffic safely and efficiently. Fatal accidents and

Jan 1, 1982

By Riley TW

This paper describes a Process Simulation Package for modelling the steady-state operation of a mineral processing plant. There are two levels of input allowed into the package. The first allows simple manipulation of the process models within a defined modular format which enables a wide range of process systems to be simulated. "The second level of input is via a Command file which allows plant models to be defined and changed without reference to the code or the requirement of any recompiling of the programme sources. The Command file interface was designed for use by metallurgists and assumes a sound knowledge of the system being modelled. As such it is an effective tool for metallurgists rather than a user friendly generalised package for the layman.

Jan 1, 1985

By Kabel J. G

While a per onnel location system is primarily used to check that nobody is left in the mine at firing time, it is also useful for contacting people, uch a foremen, shiftbosses and tradesmen, who travel over several mine levels during a shift. The system installed at The Zinc Corporation, Limited, Broken Hill, uses punched coded plastic identity tags, with "In" and "Out" tag readers on each level. When entering a level, the employee inserts his tag in the "In" reader, and when leaving, in the "Out" reader. Each reader is connected to a central computer which shows who is still in the mine and their location.The system has been used on 3 levels by 21 men for a trial period of 4 months. It ha proved reliable in an underground mining environment, and employee acceptance has been good.

Jan 1, 1984

By Dorricott M. G

Rock bolt installation is generally carried out in two steps. First the hole is drilled and the drill steel is extracted, then the bolt is inserted into the hole and tightened or grouted. With single pass bolting (SPB), however, these two steps can be carried out at the same time. This kind of bolting system has at least three advantages, (1) the time used for the bolt installation could be reduced, (2) the condition of safety for the operators could be improved, and (3) the degree of automation of the rock bolting practice could be increased. The study presented in this paper is concerned with the development of the SPB system. The current state of the system is discussed, and further improvement of the technique is explored.

Jan 1, 1992

The prime requirement is market, which for NZ inevitably means overseas markets. In order to be internationally competitive, the economies of scale and mechanical handling are essential. Since significant markets have not been sought, the full extent of our industrial mineral potential is not known. In general the technology exists to impart the desired quality, but at a price. Price is the main constraint, which may confine truly competitive operations to coastal situations to avoid high internal freight charges. Some commercial deposits of construction materials are being sterilised by zoning, making the costs to the consumer and country unnecessarily high. Unless management is enlightened and marketing is forceful, it can restrict growth. There is a good case to mount a search for phosphate minerals. The main growth areas are likely to be direct shipping ores like limestone, silica sand, and olivine, but in particular pumice.

Jan 1, 1978

By R J. Everett

The mining industry is beginning to adopt quality systems based on the requirements of International Standards for quality assurance, such as the ISO 9000 series. Indications from similar industries are that considerable benefits are to be had from their adoption. This paper describes the use of the International Standard ISO 9001 for quality assurance within BUKA Minerals Limited. This provided guidance for the development of a clear statement providing agreement on the processes to be followed and the outputs required when dealing with outside service providers. Discussion focuses on the interaction with BUKAÆs consultants and contractors during the specification stage, resulting from the application of quality assurance techniques. Risk analysis was used to identify and manage the risks associated with the companyÆs contract for geotechnical and mine design services and the tender for a mine development program of work during the feasibility stage of the project. Setting acceptance controls for the deliverables from such contracts is traditionally fraught with difficulty. BUKA used Failure Mode and Effect Analysis for exposing underlying risks that were not effectively being countered. The briefs were reviewed and additional controls were developed to manage the risk. These controls have provided clearer instructions to the consultants and contractors, indicated audit points for the company and defined the deliverables. There exists within the company, and among its outside service providers, a clearer understanding of what is to be achieved and how it will be measured. The process has imparted considerable confidence to both parties on how the work will proceed and what outputs are to be provided. Some discussion is provided on how quality principles are being applied throughout industry and commerce, generally, and how they may apply to the mining industry. The paper argues that, far from being an appendix to the tendering process, Risk Management should be a mandatory step integrated into the definitions of the work.

Jan 1, 1998

By J L. Merritt

Effective minesite water management requires that this issue be treated as a risk management exercise. The management process is generally far from simple and by necessity must involve a range of personnel covering a siteÆs commercial, operational and environmental interests and responsibilities. The challenge to be collectively faced by these stakeholders is to strike the correct balance between risk and cost. On the other hand, the challenge to be faced by technical services support personnel is to provide stakeholders with information in a format that they can use with confidence. This paper presents the application of continuous operational simulation (OPSIM) modelling techniques to establish appropriate risk profiles for minesite operations. It is necessary that the format of these risk profiles be generic and equally applicable for defining the risk of occurrence for a relatively comprehensive range of activities û eg from of a non-compliant discharge, to the risk of failure to meet production targets. What is more, the profiles need to be quantitatively based and capable of reflecting change in system response to varied operational or management strategies. The techniques presented in this paper are based around a key assumption that long-term records of the climate contain within them sets of sequences that are representative of what can be expected in the future û that is, the droughts, floods, cyclones, good years and bad, long or short, and everything in between. Therefore, if these historical records are run through an OPSIM model for a particular site, then the simulated operational characteristics can be taken as being representative of what can be expected in the future, in the long-term. This lends itself to statistical analysis and translation into the required risk based format. Water Solutions Pty Ltd have been working with Capricorn Coal Management to develop a relatively comprehensive OPSIM model of their operations at German Creek Mine, Central Queensland. Outcomes from the modelling have been used in recent times to provide mine management with risk-based guidelines for both securing and containing mine water inventories. One of the more interesting tasks has been to establish risk based inventory levels that, if reached, would trigger the immediate implementation of a contract for the desalination and re-use of mine water, at predefined rates. Also, lead-time warning of the occurrence of a possible trigger is of importance to operational and commercial planning. To service this requirement the OPSIM model is regularly used to produce lead-time estimates to defined levels of confidence. Case studies of these, and other, applications of the OPSIM model at German Creek Mine are presented in this paper and serve to demonstrate an effective methodology for practical risked based water management.

Jan 1, 2003

The establishment of vegetation onto open cut mine spoil is dependant on the nature of the soil and rock strata of the overburden. Experience has shown that in the Bowen Basin of Central Queensland the nature of the minespoil changes considerably as subsequent and deeper mining strips intercept changing rock strata. The different mixes of strata at the surface of reshaped spoilpiles can produce variable response in the sown vegetation cover. It is usual that land features of mine sites are known in detail and are depicted on mine or locality maps. Subsurface strata and lithology descriptions are available and are used for planning of open cut mining operations. Surface and subsurface data can also be used to estimate the intrinsic nature of overburden through the use of fence diagrams. Lithology at points along a mined strip can be obtained and used to describe overburden. Indications are that correlations exist between salinity of overburden components and the response of vegetation. The developed procedure thus becomes a useful tool for the prediction of revegetation Practices.

Jan 1, 1987

By B D. Sowerby, N G. Cutmore

Improved process control can be achieved through the accurate and reliable on-line measurement of critical process parameters in real time. Over the past few decades on-line analysis techniques have been developed and applied in the mineral and energy industries for the measurement of process stream composition, mineralogy, particle size and flow rates. This has led to increased throughput and product quality while reducing processing costs and minimising emissions. The support of a sustainable mineral processing industry will require the further development of on-line analysis and control technologies. The application of developments in instrumentation combined with improved control strategies will lead to improvements in process efficiency resulting in large economic benefits to the industry, reduced energy usage and lower process emissions. There is a clear convergence of interests in being able to better measure and control minerals processing in terms of the triple bottom line of economic, social and environmental impacts. Technology is increasingly becoming available enabling measurement across the entire spectrum of minerals processing from mining to hydrometallurgy and pyrometallurgy. CSIRO is developing a range of these new technologies. A number of these developments are discussed in the present paper, namely: on-line particle size analysis and acoustic emission methods to enhance the control and optimisation of grinding circuits; on-line mineralogy of dry powders and slurries; on-line bulk elemental analysers for application on conveyor belts and in smelters; and the development of new sensing technologies for sorting base metal ores.

Jan 1, 2002

The hazard posed by underground mine fires is illustrated in the first part of this paper by means of a review of experiences in four mining countries over the last three decades. This brief review indicates that while much progress has been made generally in preventing fires and providing means of protection to miners, the possibility of disasters occurring must continue to be regarded as very real. Based upon recent investigations by the South African mining industry, an integrated strategy for providing protection to personnel in the event of a fire is outlined in the second part of the paper. The main, complementary, elements in this strategy are the prevention of ignitions, the limitation of fires, provision of protection systems and equipment, training for emergencies, and effective implementation of safety measures. Some comments are made on important aspects of these elements and on possible further developments.

Jan 1, 1988

Recent operating experience from West Australian open pit gold mines has shown that geotechnical input into initial design is rare. As a result, ground stability is poor - almost half the pits designed in this way suffer major failure.West Australian experience shows that geotechnical studies for individual mines are site specific, and therefore empirical experience cannot be transported from site to site. Geotechnical studies performed prior to design have resulted in significantly improved pit stability.

Jan 1, 1990

This paper describes the principle of cut-and-break rock excavation, in which rock is first undercut, and the undercut material is subsequently broken free by a wedging action. The current work on cut-and-break using the large rock cutting test rig at the Centre for Mining Technology and Equipment (CMTE) is outlined, and suggestions are made as to the potential advantages of cut-and-break roadheading, particularly in excavating short tunnels in hard rock in an urban environment.

Jan 1, 1993

Predictive chemical models facilitate the selection, design and assessment of aqueous chemical processes. The development of expertise in aqueous themochemistry has not matched the explosion in computer technology for modelling, which has placed pressure on the need for acquisition of skills to critically assess the appropriateness of the models produced. The 'blind faith' culture which appears to be developing must be arrested by appropriate programs at the tertiary level and professional development strategies in the minerals industry.

Jan 1, 1996

The ""multiple of exploration expenditure"" method of mineral valuation is applicable to exploration properties from the earliest stage of exploration to a moderately advanced stage but for which no resources have been delineated. While not recommended as a primary valuation method by some workers, others believe it to be the most satisfactory method of valuing exploration properties until it is possible to employ a DCF technique. In many situations facing the professional valuer, the method may represent the only semi-quantitative option available and is frequently used. Significantly it often forms the starting point in discussions to farm-in on an exploration tenement. The paper briefly reviews the definition of value as applied to mineral valuation and in particular examines the relationship between fair value and market clearing price in ""fair"", bull and bear markets. The multiple of exploration expenditure method uses previous exploration expenditure and/or future committed exploration expenditure to derive a base value for the tenements. This base value is multiplied by a prospectivity enhancement multiplier (PEM) with adjustments for market premium or discount and consideration of the quality of the exploration team to derive a fair value for the tenements. The paper will demonstrate that there is no necessary nexus between fair value derived from the method and present book Values.

Jan 1, 1994

By B Banerjee, H Masoumi, X Shen, S Raval, D Tannant

Structural mapping of pit walls can be performed using digital images and photogrammetry software, but the performance is limited by weather and environmental conditions including dust, rain and light. On the other hand, active sensors such as terrestrial laser scanners (TLS) and total stations (TS) suffer from vertical orientation bias and occlusions when persistent discontinuities dip at the same angle as the scanner line-ofsight. The recent development of the compact light detection and ranging (LiDAR) systems has made it possible to mount these sensors on unmanned aerial vehicles (UAVs) or drones which offer the potential to overcome limitations that are inherent in existing mapping systems. This study details the research involving integration and application of an advanced UAV-LiDAR system for structural mapping of a highwall. A state-of-the art laser scanner with an inertial measurement unit (IMU) and real-time kinematic global positioning system (GPS) was integrated on to a UAV. The system was first tested in a laboratory condition. Then the UAV-LiDAR system was employed to map a highwall of a coal mine. The planned flight trajectories tested the system at variable distances from the highwall face and at various speeds. The raw data collected from individual sensors were fused, filtered to remove noise, and segmented to produce a surface scan model. Finally, the point density and surface coverage were measured using the surface scan model of the highwall. The parameters were compared with equivalent measurements computed from a reference TLS data. The study demonstrates the capabilities of a UAV-LiDAR system to generate accurate and occlusion free data for mapping highwall geological structure with very quick and efficient flights in the field. CITATION:Raval, S, Banerjee, B, Shen, X, Masoumi, H and Tannant, D, 2018. Evaluation of a UAV-LiDAR system for mapping geological structures in an open pit highwall, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 496–503 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Askew J. E

All facets of current practices of cable dowelling at The Zinc Corporation, Limited and New Broken Hill Consolidated Limited are re- viewed. This includes materials specific- ations, installation practices and design pro- cedures. Cable dowelling for cut and fill stoping, square set timber stoping, longhole open stoping and level reinforcement is considered. Installation is simple and can be mechanised to eliminate heavy lifting. Quality control is essential for optimum performance of the re- inforcement. Design patterns must consider the mining method, reinforcement economics, acceptable stability standards and mine production priorities.

Jan 1, 1977

By Darby H. P, Vincent R. J

Sydney's Eastern Suburbs Railway from Central to Bondi Junction required the construc- tion of 10.4 km of single-track tunnel and five underground stations. Much of this work took place beneath the commercial centre of Australia's largest city. This paper discusses the general precautions taken and the specific design solutions made for such problems as support of a 15-storey building with foundations several metres above the excavation to ensure negligible differential settlement, excavation immediately below running tunnels, underpinning of multi-storey buildings, tunnelling under massive masonry retaining walls and demolition and rebuilding of part-completed structures.

Jan 1, 1981

The need to estimate the block size distribution of a jointed rock mass is of great importance in the design of blasting rounds to attain a pre- established fragmentation. Other Geomechanics topics, such as ,hydraulic behavior of rock-masses, as well as the determination of their strength properties, also require the accurate prediction of a rock-mass composition in terms of block size taking in due account the three dimensional interference of joints and other geologic discontinuities. In this paper, a method for computing the block size analysis of a jointed rock mass is described, using as input the common geologic data (dip and strike) of fracture planes existing in a rock bench prior to blasting.

Jan 1, 1977

The mmmg operations carried out by North Broken Hill Limited, necessitate the use of four shafts for the haulage of ore, men, and supplies. These are:-1. Blackwood's Shaft.-British Section, which has 100 feet intervals between levels to the bottom 800 feet level plat;2. Thompson's Shaft.-British Section, which has 100 feet intervals between levels to the bottom 1400 feet level plat;3. No. 1 Shaft.-With intervals between levels:(a) 100 feet to the 800 feet level,(b) 150 feet from 800 feet level to the 1700 feet level;4. No. {2 Shaft.-2770 feet from collar to bottom plat, with intervals between levels: (a) 100 feet to 800 feet level, (b) 150 feet from 800 feet level to the 2600 feet level. (c) 170 feet from 2600 feet level to the 2770 feet level.All shafts have two cage compartments, and the No. 2 Shaft a skip installation in addition.For the control of hoisting operations an electric signalling system is installed on each shaft, and is supplemented by a counterbalanced rope pull ("Knocker line") operating a surface gong. The latter system is shown diagrammatically in Fig. 1.Two sets of electrical equipment are used per shaft. The first, shown in Fig. 2, is that operated by the braceman or...

Jan 1, 1940