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By Hosking IA, Mirkov P

Among the solutions currently being considered for improving traffic flow in Sydney are the construction of major road tunnels, principally the Eastern Distributor Tunnels, leading from the end of the Cahill Expressway to Drivers Triangle and South of Taylor Square and the Sydney Harbour Tunnel, which incorporates sections of driven tunnel at the northern and southern sides of the harbour. The Eastern Distributor Tunnels, known as Stages 2 and 3 of the Eastern Distributor Scheme comprise: Stage 2 - A south bound two lane tunnel from north of William Street to Driver's Triangle. The southern end includes two Y junctions (locally 3 to 4 lane widths) with exits into South Dowling Street, Anzac Parade and Moore Park Road. Stage 3 - A north bound, two lane tunnel from Taylor Square to Palmer Street just north of William Street. Further details of the Eastern Distributor Tunnels are given in the paper by Baxter, Chappel and Fishburn (1986) which is included in this conference.

Jan 1, 1987

The basic issues of education for the mineral industry which emerge from experience and from a study of relevant literature are presented with the object of promoting. discussion. The subject is considered primarily from the university point of view and relates more to the disciplines of mining and mineral processing than to geology or perhaps metall- urgy, but the conclusions have wider implic- ations. Continuing education, being the subject of a separate paper, is only briefly discussed. The important and particularly relevant training and industry role of the technician engineer and technician are not considered.

Jan 1, 1974

By Torres F, Cerda I, Gimenez P, Gonzalez G, Castelli L

Slurry density measurement, specially in cyclone feed streams, is fundamental to grinding circuit control. With the purpose of increasing the availability of such a measurement, the design of a soft-sensor in an actual grinding plant is addressed in this paper. The system is designed to substitute the momentary unavailability of the real density sensor, either because it has failed or because it has been removed for any other reason. The ARMAX model structure is determined using the stepwise regression method. Starting with a list of the candidate variables, the method selects, one by one, and in a systematic manner the variables which best model the measurement to be replaced, choosing them from the set of presumably correlated candidate variables. In this paper not only the single measurements are included in the list of candidates, but also combinations of such measurements having physical significance. A phenomenological model has been built with the purpose of determining these combinations. It turned out that in most of the cases the components of combined measurements having physical significance were selected by the stepwise regression method, instead of the single measurements. Actual grinding plant data is used to determine the model structure, to estimate the model parameters and to test the predictive capability of the developed soft-sensors. Good results are shown to be obtained during periods of up to 30 hours of the density soft-sensor operation.

Jan 1, 1995

By B Sno, P A. Cockburn, R C. West, C U. Jones

Clyde Materials Handling (CMH) and WorleyParsons have developed a concept for a flash furnace feed system using the specialist pneumatic conveying equipment expertise of CMH and the flash furnace process experience of WorleyParsons. CMH has developed a proprietary volumetric feeder (called a Rotofeed), which is extremely accurate and overcomes many of the problems inherent with loss-in-weight screw feeders and drag chain conveyors, previously regarded as state-of-the-art. Initial indications are that the Clyde-WorleyParsons feed system could deliver the following benefits to flash furnace operation: accurate pulseless delivery of feed material to the head of the burner leading to improved combustion performance and process stability; highly accurate split to the individual quadrants of a conventional burner tube, or provision of a smooth hollow curtain to a burner without guide vanes; decreased pressure pulsation in the furnace due to improved combustion control and performance; and decreased temperature fluctuations in the furnace due to improved combustion characteristics and hence reductions in refractory thermal stress and wear.

Jan 1, 2005

By R E. Hobbs, O Grabandt, C Das

Mine hoisting is carried out from depths of up to 4 km. At extreme depths, the ropes are so heavy that a large part of their capacity is employed in lifting themselves. Consequently, deep mines have an intermediate winding station. Even at lesser depths, the weight of steel wire rope reduces the possible payload. Of course, steel wire ropes have, over the years, demonstrated exceptional reliability and acceptable lifetimes. The use of steel is supported by well established operating rules and sound NDT methods. However, lightweight ropes made from synthetic fibres could be of great benefit to the industry, with the prospect of eliminating two-stage winding and substantially increasing the payload. Initial tests, in cycling over sheaves, have demonstrated that an aramid co-polymer fibre, Technora« is a potential candidate for this type of service. This paper presents results of testing carried out on aramid co-polymer and other synthetic fibre ropes. These results hold out the prospect of exceptionally long lives. Possible NDT methods are explored including optical fibres with optical time domain reflectometry or with Brillouin scattering, plus a method based on carbon fibre continuity. The introduction of aramid co-polymer ropes will require extensive testing and a program is proposed in the format of a Joint Industry Project.

Jan 1, 2005

By P N. Martens

In the course of the development of the Report of the World Commission on Environment and Development (WCED) in the 1980s an expression was introduced in the public discussion on environment and development that influenced the international and national policies of the last 20 years in all areas: sustainable development. The UN decided in 1992 to implement a program with the Agenda 21 which contains the demand for developing indicators for sustainable development. In this context an indicator is understood as a quantitative or qualitative measure that can be measured or described throughout time and which moreover is able to depict the current status and changes. In order to enable for a simple holistic assessment of sustainable development, highly aggregated indicators are required, which integrate the criteria identified as relevant within a framework to be defined. In the presented paper, sustainability indicators for the mining industry are developed that account for the allowances of the sustainable development concept and the Agenda 21. The indicators are quantifiable and traceable through time so that developments can be traced and assessed. Furthermore, the indicators account for the multidimensional aspect of sustainable development. They are designed to allow for the integration of several dimensions in one indicator. The premises that are underlying the development of the indicators are the minimisation of negative impacts on the environment and society while simultaneously considering the maximisation of social and economic factors. Moreover, the participative momentum that is part of the sustainability idea is safeguarded in explicitly integrating the social acceptance of certain measures into the assessment. The indicators presented are based on the logical combination of statements through the use of Boolean algebra. Starting with basic statements for which the logical value is oriented on the sustainability paradigm, complex multidimensional statements can be constructed and assessed.  

Jan 1, 2009

The author presents various procedures for the choice of dri-ving systems for mining, including the method of indeterminate Lagrange factors and linear programming.The possible application of the points-awarding method is demonstrated.It allows for taking into account both surd and commensurable characteristics of a driving system for mining. Also, the method of economic efficiency factors is outlined.All these methods make possible the best choice of a driving system, from the as-pect of electric energy saving. Two examples are given.

Jan 1, 1985

The complete life cycle of a production facility has many phases requiring many different skills and many different personalities. It is not unlike the life cycle of a person and many parallels can be drawn from it. I leave some of these analogous situations to your fertile minds. The author, having worked in operations, plant design, plant commissioning, marketing and many other interesting situations through the industry has drawn from this experience and examples given by many associates in the industry.The phases seen are as follows: Concept Studies û someone has a bright idea of how to make a dollar. Scope Studies û what possible processes/options that could make a dollar. Prefeasibility Study û the æviableÆ scope options are studied to develop feasible options. Feasibility study û defines the concepts that should be designed to make a viable project thus enabling financing and project commitment to be made. Detailed Design û an intermediate step that consolidates the inputs to give a robust plant that can be constructed.Construction û people can see what they thought was going to occur and start to understand the plant. Commissioning û the hand-over of æownershipÆ from the conceiverÆs to the operators. Operations û the ætoyÆ has become reality and money must be made. De-commissioning û the plant has seen out the useful life of the ore deposit, it now goes through a further process required by society.Across these phases of plant design run several countervailing management requirements that can influence the outcome of the plant design. Some of the management rigours that have to be applied to the various phases are as follows: costing basis of the various phases; operational and maintenance reviews; sustainable development; risk assessment; reliability reviews; equipment availability; commissioning time; and environmental review.This paper endeavours to awaken people to the phases that projects require for a successful outcome and the management rigour that has to be applied throughout the phases to ensure the correct intellectual horsepower is applied at the right time to ensure the best outcome.Many of you would be parents and realise this is not unlike the development of children, teenagers, adults, retirees and ongoing.

Jan 1, 2002

Future depth and production limitations of an ore hoisting system are fixed by its initial design criteria. There is little scope to extend these limitations once installation is completed. Depth and production rate upgrades from the initial duty to the hoistÆs practical limitations require capital expenditure in stages, each of which can be defined when assessing the initial system design criteria. A means of presenting and assessing the design criteria, the limiting factors in each option and the relative present and future capital costs is necessary to arrive at a solution that delivers the best value to the mine. Application of this technique to recent friction winder installations and upgrades in the Australian mining industry is of particular interest; however, the analysis methods are also applicable to drum hoists. It is usual to specify a minimum hoisting capacity and depth, based on mine ore handling design and production needs. The final hoist depth and production rate are usually a result of the initial hoist design and hence it is useful from the outset to specify a required production versus depth envelope for the mine. Technical solutions can then be modelled within this envelope at their initial and final duties and a comparative analysis made against the cost of installing and progressively upgrading each solution. Understanding the factors that constrain each solution to a maximum production rate at a given depth is important, as the costs of overcoming limiting parameters such as rope tread pressure and motor power can be significant. The task of understanding and evaluating the options open to the hoisting system designer is simplified using this approach. Communicating the results of a multi-dimensional problem such as hoist specification is also made easier using the graphical methods inherent in the analysis.

Jan 1, 2005

By Shibata Y, Shimizu R, Fukushima A

Kobe is divided by the Rokko Mountains, runn- ing from east to west. The southern section of Kobe is highly developed in contrast with the northern section, but big, new residential pro- jects like the Hokusetsu New Town and Hokushin New Town are steadily being developed. To handle future traffic between the two sections of the city, the double-tracked Hokushin Line, now under construction, will connect the Shin Kobe Station of the Kobe Municipal Transit (Kobe's subway system) to the Tanigami Station of the Kobe Electric Railway. The locations of Kobe city and Hokushin Line are shown in Fig.-1 and Fig.-2 respectively.

Jan 1, 1987

A generalised mathematical model for hydrocyclone classifiers was developed by the author (Nageswararao, 1978) using dimensionless groups which include phenomenological characteristics as independent variables. This model is incorporated in JKSimMet, the steady state mineral processing simulator developed by JKTech.Recently, when this model was rewritten (Lynch and Morrell, 1992), in terms of variables other than those used by the author, a few errors have crept in. For example, while the exponent of (Du/Dc) in the equation for d50e should be negative (-0.47), it was recorded as positive (0.47). Also, the exponent of (DoIDe) in the equation for pressure drop should be 0.67 and not 0.60. In the same equation, the exponent of Dc would turn out to be -0.10 and not 0.15. These are clearly attributable to typographic and rounding off errors, while transforming the original equations.More recently, Cilliers (pers comm) has done a comprehensive evaluation of the major semi-empirical models for hydrocyclones.He observed that the major difference between the cyclone model developed by the author and other models lies in the method of quantifying the effect of spigot diameter on d50e. He noted that while all other models predict an increase in d50e with a decrease in the spigot diameter, the model as cited by Lynch and Morrell (1992) predicts just the opposite. However, he conjectured correctly that the discrepancy could be due to a typographic error. As the model is still unpublished, it is felt that the original model equations should be recorded with the correct exponents, so that errors in predictions other than those due to the limitations of the model itself could be avoided. They are given hereunder.

Jan 1, 1995

Prefeasibility planning and cost estimation of conveyor systems has historically been undertaken by comparing fi xed plant transport requirements to that of similar systems in service. This paper describes the development of a prefeasibility conveyor technical design and cost estimation application using Microsoft Excel Visual Basic for Applications (VBA) platform. The application tool known as D-Convey (Dachshund Convey) was developed with the goal enabling the end user: to develop a technical model for conceptualised conveyor systems, to perform economic analysis on the developed technical model, and to conduct a comparative and risk analysis. An Excel VBA based platform was utilised to draw upon both the analytical and graphical capabilities of a spreadsheet. Some of the features of D-Convey system include a revolutionary dynamic graphical help system, known as the 'information pane' in lieu of traditional help fi les as well as the use of familiar graphical user interface elements such as the MS Offi ce 2007 task ribbon. The D-Convey system incorporates material database allowing for mass handling prefeasibility estimation in other industries; it has been validated at a local quarry.

Dec 6, 2010

Part of a four-year course in metallurgy, dealing with metallurgical process engineering, was designed for students to acquire knowledge and skill from physical science, metallurgy, process engineering, and social science. Principles of education, and guidelines obtained from a study of professional practice, indicated that students may learn effectively through a planned sequence of problem-solving exercises based on the diverse functions of metallurgists in industry. The more important characteristics of the curriculum and a few illustrations of the problems are included. An outline is given of the current procedures used to develop parts of the curriculum, and of the students' diffic- ulties and achievements.

Jan 1, 1984

By Randall C

Energy studies have been undertaken at a number of open coal mines in the Hunter valley. A range of energy efficiency benchmarks and targets have been established, which, when applied across coal mines, will assist in leading to a significant improvement in energy efficiency in the coal mining industry in NSW, thereby leading to an improvement in environmental performance. Typically, energy efficiency improvements of 20 per cent and higher appear possible at many mines leading to a commensurate reduction in this controllable operating cost, ie energy. On the basis that annual energy costs and net profit are similar for many mines, a reduction in energy costs by 20 per cent will lead to increase of 20 per cent in net profit.

Jan 1, 1995

The Pilbara iron ore industry has seen rapid growth over the last five years and is now bracing itself for another expansion which will take its seaborne trade to beyond 500 Mt/a. To effectively utilise port capacities, port stockpile turnover will become extremely rapid and each stockpile built will have to be of a quality which is precise and unbiased.Sampling systems at the older Pilbara mine sites were generally designed during the 1980s and reflect the practices which were considered adequate at the time. Hence, the precision of measurement at production sites is generally unknown and quality assurance (QA) of sampling facilities falls short of what current best practice suggests. This paper suggests practical improvements in sampling practices and quality assurance, which will assist the industry in achieving quality objectives in times of rapid mining expansion.

Jan 1, 2008

In-seam drilling is conducted mainly to drain coal of gas and/or water prior to development or extraction. The requirements of inseam drilling for gas drainage have mainly surpassed the technical limits of rotary drilling and are mainly being addressed by guided down hole motor drilling, albeit at a higher cost. There is an increasing application of in-seam drilling to detect geological structures or other hazards or their absence in advance of mining to reduce the risks of underground mining. Close collaboration between miners, drillers, geologists, researchers and suppliers over the last four years has seen many advances made to improve the accuracy and reliability of inseam drilling. With such developments will come closer control over the ventilation and safety of future mining under deep gassy conditions, but not without costs. The paper summarises the current applications of inseam drilling, recent technological advances and the next generation survey and geophysical sensing tools which are currently being developed

Jan 1, 1998

In many mining operations, the truck and loader equipment represents the bulk of the invested capital and the majority of the mine operating cost. The profitability of these mines is therefore critically linked to the efficiency of the truck and loader operations. The various factors which affect the productivity of trucks and loaders are analysed by computer simulation, and the results presented in a form allowing assessment of the importance of each factor on overall productivity.

Jan 1, 1983

This paper carries on from an earlier paper 'Cemented fill practice and research at Mount Isa' and reports further on the laboratory programme at Mount Isa to develop a cheap cem- ented fill using Company waste products. The practical economic significance of availability of cheap cementing agents is re- viewed, with the various alternative approaches available The basic approach adopted within this paper is that use of reactive pozzolans such as ground slags to replace a proportion of the Portland cement in the fill can make mining methods employing cemented fill more economic- ally competitive with other mining methods.

Jan 1, 1973

By P H. Warton

It is proposed to construct a gold extraction plant at Matatoki, near Thanes. Ore to be processed at the mill will come from reopened and enlarged underground mines north of Thanes. The project has been described in some detail in environmental impact reports (Worley Consultants Ltd 1984, 1987), and is now at an advanced stage in terms of obtaining the required statutory approvals.

Jan 1, 1987

By Lunardi P, Pelizza S

The link between the Lecco bypass and major road SS36 (Italy) requires the construction of a double two-way tunnel (through the mount San Martino carbonatic massif). The tunnel excavating section is about 90 sqm through mount San Martino carbonatic rocks. The mountain sides are unstable and are often the scene of large collapsing landslides (tens of thousand cubic metres). The tunnels are very close to the mountain sides. The use of blasting induces vibrations which may reach the Lecco built-up area. With a view to avoiding such dangers the excavating operations were carried out in two successive stages: - opening a pilot tunnel, whose section is about 10 square metres, by a full face TBM to eliminate the more intense vibrations which are generated by the first opening charges; - successive enlargement by blasting.

Jan 1, 1987