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As modern techniques of Petroleum Exploration and Development are rela-tively new in Australia,2 the alien terms "Mud Logging" and "Core Analysis" will bear explanation. Mud Logging and Core Analysis are two of the Petroleum. Industryts most useful "tools" in the successful search for, and development of, commercial oil and gas deposits. Modern Mud Logging could be more accu-xately termed "Drill Cuttings and Mud Gas Analysis". Presently, mud-logging has its greatest application in exploratory wells where subsurface geologic control is at a-minimum.

Jan 1, 1962

Past and present developments in the use of blast furnace slag in the manufacture of glass are outlined. The crude slag from Port Kembla is beneficiated by the Mineral Resources Division of Australian Consolidated Industries Ltd. at Mascot using a dry magnetic separation process which reduces the iron level in the slag to an acceptable value, The chemical and physical properties of both the crude and beneficiated slag are given and compared with those of other slags used in the manufacture of glass. Slag is added to intro- duce alumina into the glass and its addition to the glass batch also results in faster melting and refining. Slag was first used in Australia in 1968 and its use has increased steadily year by year. At present about 16 000 tonnes of slag are used per year, mainly in amber and white glass. Beneficiated slag is used'in three plants to supply all the alumina required in the amber glass and in four plants to supply part of the alumina required in the white glass, the amount added depending on the acceptable iron level in the glass. Slag is also used in limited quantities in the manufacture of both dark and light green glass.

Jan 1, 1979

Coal pillar design has been based on generalised formulae of the strength of the coal in a pillar and experience in localised situations. Stress measurements above and in coal pillars indicate that the actual strength and deformation of pillars varies much more than predicted by formulae. This variation is due to failure of strata surrounding coal. The pillar strength and deformation of the adjacent roadways is a function of failure in the coal and the strata about the coal. When the pillar is viewed as a system in which failure also occurs in the strata, rather than the coal only, the wide range of pillar strength characteristics found in the UK, USA, South Africa, Australia, China, Japan and other countries are simply variations due to different strata-coal combinations and not different coal strengths.This paper presents the measured range of pillar strength characteristics and explains the reasons. Methods to design pillar layouts with regard to the potential strength variations due to the strata strength characteristics surrounding the seam are Presented.

Jan 1, 1998

Territory Iron has seen fit to revive the old Frances Creek iron ore mine some 30 years after it ceased operations in AustraliaÆs Northern Territory. The key to this revival has been the changes that have happened since market forces, infrastructure limitations and a cyclone combined to force its closure. As it breathes life into this old mine, the Company is serious about its responsibilities to its shareholders, to its workers, to local and regional communities and to the environment. This paper addresses how Territory Iron has approached technical, operational and regulatory issues that apply in Australia. Some insight may be gained into the myriad of tasks that mining companies face to revitalise an old mine. These tasks vary from employing the latest exploration tools, best practice drilling, sampling and modelling of orebodies, optimisation of pit designs and schedules, maximising product value by blending, optimising infrastructure usage and minimising capital and operating costs. All of this has to take cognisance of commercial, environmental and other issues including Native Title.

Jan 1, 2007

By Boyd G

Deep mining in the Collie Basin has suffered with high levels of water flow and sediment in-rushes throughout its 90 year history. Current day experience in working conventional bord and pillar by mainly mechanised means is that advance to the dip is impeded at about the 150m depth of cover by excessive water flow and pressure bursts. Extensive analysis of exploration borehole data and reconstruction of depositional environments helped define important hydrogeological characteristics of roof and floor aquifers, aquitards and aquicludes. Hydraulic parameters were estimated with some accuracy using indirect methods, and later confirmed by pump testing. Groundwater flow modelling showed that mine scheduling would have to be a balance between down dip and lateral development if aquifer pressure heads were to be decreased to suitable levels. Since pressure reduction in aquifers immediately above and below the mine opening was. identified as the key aim in groundwater control, a series of trial in-pit dewatering holes were installed, and demonstrated pressure heads could be reduced at rates compatible with a mine extraction sequence which, in turn, controlled the rate of down dip mine advance. A case history of the successful application of in-pit dewatering systems within difficult hydrological conditions for mining is described, with emphasis on the close collaboration required between hydrologists, mine planners and operations personnel.

Jan 1, 1988

By Hughes CA

The need to recover metals from low grade deposits, old tailings, etc., combined with improvements in equipment design and the development of new extractants, has resulted in solvent extraction (SX) metal recovery reaching new importance (Webster & Ferron, 1993). The basic principle of solvent extraction is the use of an equilibrium system in which a metal ion is transferred from an aqueous phase into an organic phase, (Equation 1), (Ritcey, 1984). M + E ME . (1) The organic extractant (E) is usually specific for a certain metal ion (M) and forms a metal complex in the organic phase, leaving the impurities behind in the aqueous phase. To recover the metal, the equilibrium is reversed and the metal ion is transferred back from the organic to another aqueous phase in a process called stripping. The metal is then recovered from the aqueous strip solution, usually by electrowinning.

Jan 1, 1990

By Baafi EY, MacKenzie -Wood P

An experienced and reliable knowledge of fire fighting procedures is necessary for mine emergency situations. Since experts in this area are scarce the technology of expert systems lends itself as a suitable component in the decision making process. This paper describes an expert system that is being developed for this purpose. The expert system. RESCUE. is a knowledge-based computer programme which incorporates the judgement, experience, rules of thumb. mine environmental conditions as well as human intuitions in the mine rescue operation. RESCUE makes decisions such as whether or not the affected area should be sealed.' whether or not rescuemen should be withdrawn, and which fire fighting agent is most appropriate for the situation. The IF..... THEN rules written in the VP-EXPERT shell contains antecedents and conclusions based on environmental as well as other conditions prevailing in the mine. For example, the CO/Oz deficiency ratio indicates the progress of heating; explosibility trends are given by varying flammable gases C CH4,H2,CO) in relation to oxygen concentration, and barometric pressure falls may affect explosibility by increasing CH4 content in workings. The interaction of such numeric-based rules with others rules reflecting the experience and judgement of the experts assist the system to arrive at its conclusions and subsequent course of action.

Jan 1, 1988

Blast furnace slags which fall into the quaternary system SiO2 - A1203 - MgO - CaO have latent hydraulic properties which depend on the degree of vitrification. When the oxides com- bine to form Calcium Silicate Hydrates and other products of hydration the bonds between elements are at a lower energy level than those which exist in the glassy state. Transition from the glassy state to the crystalline state is thermo- dynamically favoured and, in the context of this paper, such slags possess internal energy. Manufacture of Portland cement is respon- sible for about 3.6 per cent of total industrial energy consumption in Canada. Pyroprocessing accounts for about 83 per cent of this figure or 3 per cent of the total. The processing of blast furnace slag to a condition in which it can be used as a partial substitute for Portland cement requires no pyroprocessing and, on average, only about 11 per cent of the energy needed for Portland cement. In North America the benefits of slag as a cementitious materials have been obscured by other considerations, the most important being commercial strategy. This situation has under- gone radical change as a result of the rising cost of energy, and government pressures to conserve energy.

Jan 1, 1979

In six deep hard coal mines situated in the coal district of the Saar and Lorraine, Saarbergwerke AG produce annually 9 to 10 million tons of coal. The coal is either coked or fired in power plants. Comprehensive planning work is done for the producing coal faces, 15 stone drifts and 60 seam headings. The computer can assist in drawing up the short- and medium-term planning by taking over, on the one hand, work done so far by hand and by supplying, on the other, additional information. The computer can draw up time schedules, can do quantitative calculations, can draw up plans for the em- ployment of manpower, machines and other equipment, and can calculate cost and earnings. It is ensured that all part plans are always adjusted to each other. Because of the volume of work involved, planning in this form and extent becomes possible only by the computer. Especially with the periodical continuation of planning, the new system facilitates the work to be done. The ideas of the planning engineer are and remain the basis of all planning work and the computer gives him an aid to assist him with calculations, report writing and feasibility studies.

Jan 1, 1977

By E S. Souza, H Delboni Jr, M F. Calixto

This paper aims at presenting the results of laboratory, pilot plant and simulation studies for the design of the grinding circuit for the beneficiation of compact itabirites from the Conceitpo mine. Two alternatives were investigated, both utilising the current crushing circuit up to tertiary crushing. Under alternative #1, quaternary crushing was considered to produce the feed of the ball mill; under alternative #2, high pressure grinding rolls were selected to prepare the ball mill circuit feed. Pilot scale studies pointed towards the use of high pressure grinding rolls (HPGR). The circuit design was based on a throughput of 720 t/h, representing a nominal solids flow rate of 600 t/h, considering a design factor of 1.2, and P80 of 95 ¦m.

Jan 1, 2007

Bakelite is fairly widely known as a suitable material for the mounting of ore specimens, concentrates and tailings for microscopical study, but has not as yet had extensive application. It is the most suitable mount for specimens which are to be held in the mechanical holder of a polishing machine, based on that described by J. W. Vanderbilt*, which is installed in the Geological Department of the Melbourne University.Bakelite products are prepared by subjecting bakelite powder to a temperature of about 1600 C. under a pressure of approximately two tons per square inch for a period of four minutes. The shape and size of the products are governed by the use of suitably constructed dies. When the concentrate or tailing is mixed with the bakelite powder, a briquette is produced which can be polished so that the opaque minerals in the sample can be examined microscopically in the same way as in a piece of solid ore. A simple machine for the construction of these briquettes has been described by Head and Slavin. It consists of a small four-pillar press in which the pressure is supplied by...

Jan 1, 1933

By Williams RJ

This paper presents an overview of the design and development , application to date and potential of a real-time return gas monitoring system.Initially developed as an ACARP/Industry funded project, whose prime aim was to create a `turn-key', prototype, stand alone, real-time, Return Gas Monitoring System (RGMS) capable of providing quantitative assessments of gassiness levels on a shift by shift basis, enabling unusual gas emission patterns to be readily flagged.

Jan 1, 1998

By J A. Shonhardt, I Porter

All types of coal are liable to spontaneous combustion to a variable degree according to the inherent characteristics of the coal and also extrinsic factors. In order to successfully extract coal from highly capital-intensive longwall mining operations it is necessary to evaluate and manage any risks that may be present due to spontaneous combustion. A spontaneous combustion risk management plan for longwall mining is described in this paper. This risk management system comprises identification of conditions promoting spontaneous combustion risk, a laboratory or empirical risk classification system, determination of gas ladder, adoption of adequate ventilation plans and gas monitoring systems that will lead to the development of the spontaneous combustion action plan. The risk management system was applied to a greenfield site in NSW in 1992 when prediction of a high-risk category for the coal seam was made. After commencement of production a spontaneous heating problem emerged as predicted. Description of the case history of spontaneous combustion risk management for a longwall operation in this coal seam is included in this paper.

Jan 1, 2003

By R F. Johnston, I D. Sommerville

This paper presents an overview of the researches carried out in our laboratory on the application of plasma in recovery of alloy elements from waste slags and the treatment of lean ores, which are examples of advanced materials processing. After briefly reviewing the early work on the reduction of nickel, chromium, manganese, vanadium and titanium oxides, and a short investigation of the reduction of titanium oxide from the slag resulting from the blast furnace smelting of a titanomagnetite ore, the paper concentrates on the more recent studies on the reduction of an Australian scheelite. In some of these experiments, aluminium was used in addition to carbon as a reductant, in virtually all cases complete reduction was achieved within a relatively few minutes even with carbon alone during plasma processing. It therefore appears that this technique provides a possible processing route to facilitate the recovery of valuable alloying elements from non-traditional sources, or to permit process step elimination.

Jan 1, 2000

By P Trotta

The paper provides a structured methodology to investigate metallurgical problems within the operating concentrators. The strategy uses classical metallurgical data analysis as well as pulp, solution and surface analysis to determine the reasons for particular behaviours. The approach applies equally to all mineral-processing operations. To demonstrate its effectiveness a case study, based on work conducted at Pasminco Rosebery Mine, is described. In this work, the classical metallurgical analysis indicated that a significant amount of sphalerite reporting to the lead concentrate occurred as liberated particles. A combination of pulp, solution and surface analysis supported the hypothesis that the liberated sphalerite was recovered by inadvertent activation by lead ions. Laboratory studies have indicated that the use of sodium carbonate, by itself and in combination with zinc sulphate and sodium cyanide, when added to the lead regrinding mill can depress sphalerite flotation, resulting in an improvement in the lead grade/recovery curve. When this approach was tested in the plant other more dominant issues masked any positive effect the addition of sodium carbonate may have had. The plant trial highlighted the real need for additional regrinding capacity.

Jan 1, 2002

This paper describes an investigation of the sampling problems which contributed to erroneous Concentrator production forecasts at the mining operation of Bougainville Copper Ltd (BCL) in the North Solomons province of Papua/New Guinea.Reference figures provided by independently verified commercial shipment data demonstrated the existence of a bias in the calculated Concentrator production; the challenge was to identify systematic errors in each of the contributory measurements (feed tonnage and feed, tailings and concentrate grades).The uncertainty surrounding specific sampling and measurement errors precluded optimum metallurgical control and performance of the milling circuit, encouraged disputes about the difference between Mine versus Concentrator production estimates, and cast some doubt on efforts to follow political guidelines concerning a maximum feed tonnage or recovery oriented mill operating concept.An evaluation of routine results as well as specifically targeted test work identified the sampling errors associated with measured individual parameters.The emphasis in this report is on the procedure for quantitative error assessments.The measured performance of a mineral dressing plant is subject to a systematic error balance which can be derived from the more familiar weight and metal balances such as the two- or three-product formula.The resulting equations are generally valid, and they are applied to the measurements obtained at BCL's Concentrator to illustrate the method.

Jan 1, 1976

By Miskelly N

In Australia and New Zealand, the 'Australasian Code for Reporting of Identified Mineral Resources and Ore Reserves', which was released by industry in 1989, is operating successfully in a co-operative approach between industry and regulatory authorities. Similar codes or guidelines exist or are under development in the United States of America, Canada, the United Kingdom and South Africa, although the regulatory backing given to the Australasian Code is unique. International standard definitions for Mineral Resources and Reserves, and for categories of Resources and Reserves, have been under development by the Council of Mining and Metallurgical Institutions since 1994 and have already stimulated considerable convergence of definitions and reporting standards in participating countries. It is hoped that agreement on this international standard for public reporting by mining companies will be reached within the next two years, and it is expected that adoption of the standard will result in a higher and more uniform quality of reporting worldwide, with a consequently greater interest on the part of the general public and financiers in investing in the mining industry.

Jan 1, 1997

Production scheduling is an important element of the mine planning process. The production schedule specifies the quantities of mineral to extract, the source of this ore, the timing of extraction and, where necessary, the quantity and timing of backfill placement. These details are important in linking long-term strategic goals to short-term operational planning. Mine scheduling techniques form the basis for communicating information concerning the overall impact of design and planning changes to a wide range of people at many levels within an organisation. Consequently the techniques used for mine scheduling must support the decision-making process by consistently providing high quality schedules in response to revised and updated data. A new mixed integer programming (MIP) model has been developed to generate optimal production schedules for underground stoping operations. The model maximised the before-tax Net Present Value of the production schedule while satisfying constraints such as contained metal tonnage, hoisting capacity, stope geometry relationships and stope backfilling demands. Zero-one variables were used to represent the decision to extract or backfill each stope in a particular time period. Continuous variables, capable of having non-integer values, were used to denote the quantity of ore or backfill associated with a specific stope in a given time period. A case study is presented to demonstrate the significant improvement in before-tax NPV over a comparative manual production schedule in a large underground mine. The MIP model allows for further modification to reduce solution times and meet the needs of individual mines.

Jan 1, 1995

By P J. Harper

Maximising shareholder value is a widely stated strategic goal of many mining companies. Mining projects can be capital intensive and achieving good returns is essential to encourage future investment in the industry. Despite the widely accepted importance of shareholder value, the minerals industry is often accused of providing relatively poor returns when compared to other industries. There are many recent and well publicised examples of minerals companies that have failed to deliver value to their shareholders. There are numerous business improvement initiatives employed within the mining industry to assist mine operators improve performance. Some are more effective at creating value than others. Benchmarking is one technique that is commonly used to identify performance gaps and target and prioritise opportunities for improvement. However to be effective, Benchmarking must be used appropriately and result in actions that lead to measurable operational improvement. When conducting a Benchmarking project it is important to remember that the aim should be to improve value. For this to be achieved, the strategic goals must be incorporated into the process. This paper details a structured and comprehensive approach to conducting a successful Benchmarking project. Focusing on Benchmarking as a technique for measuring and improving operational performance in underground mines, the underlying drivers of best practice in underground mining are identified.

Jan 1, 2005

By Morland R

Recent influence of backfill stability on stope production in the Copper Mine at Mount Isa Mines Limited is described. Changes to the mining process to improve fill stability are described, including increased focus on fill performance, modifications to extraction techniques, increased fill quality, changes to drill and blast practice, and research into backfill stability. Several case studies are described.

Jan 1, 1995