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By Waterhouse BJ

Occurrence data of Tastubian,Sterlitamakian, and Aktastinian (all of Sakmarian Stage of Early Permian) brachiopod genera are analysed by Q-mode cluster analysis, principal component analysis, and discriminant analysis based on presence or absence of genera. Five faunal provinces and their corresponding generic associations persisted throughout the Sakmarian Stage. The additional Sasian Province incorporating the Lhasa and Shan-Thai terranes became recognisable in Sterlitarakian and strengthened in òAktastinian, implying a Tastubian-Sterlitamakian rifting event, followed by subsequent northward drift and divergence from Gondwana, and convergence with Laurasia. The nature of Permian 'Tethys' is discussed on the basis of faunal migration and abrupt changes of faunal provinciality in Lhasa and Shan-Thai terranes.

Jan 1, 1990

An efficient energy management programme can often significantly reduce a company's energy costs. The programme consists of a series of steps, namely a statement of support from senior management, assigning the management team, the energy audit, defining the goals and comwnicating with and training employees. The energy audit provides the information base from which the company can start to control and improve upon energy Usage.

Jan 1, 1983

By Haines P. W, Sweet I. P, Rawlings D. J, Page R. W, Plumb K. A

Current regional geoscientific studies across the McArthur Basin as part of the National Geoscience Mapping Accord by the Northern Territory Geological Survey and Australian Geological Survey Organisation have provided a significant amount of new data which has enabled revision of the stratigraphic and chronologic framework of the basin. This paper provides an overview of these results, with particular emphasis on new results from Arnhem Land.

Jan 1, 1994

The traditional form of project financing for resource related projects has involved project financings structured with either recourse to the project sponsor(s) or commercial banks accepting the project's risks, usually after project completion, subject to, inter alia, the nature of the project, geographical location, quality of the projected cash flows and commodity price outlook. However, the concept of commodity-linked borrowings hasadded a new dimension for borrowing opportunities for resource-oriented projects and or companies.

Jan 1, 1985

The work to be described is part of a comprehensive research on the influence of impurities on the properties of lead. The author had previously compared an electrolytic lead containing less than 0.002% total impurities with a commercial lead containing 0.008% impurities (excluding oxygen) and had shown that the former recrystallised more readily than the latter under the same conditions of cold work and annealing. This difference in properties was attributed to the difference in purity. Electrolytic lead containing only 0.0005% total impurities has been prepared and cast in vacuo. Some interesting effects have been obtained by working and annealing this lead, and by adding silver to it. The preparation of this lead, and the effects obtained thereon, are described in this paper. Thepaper is divided into the following sections:(I) Preparation of electrolytic lead.(II) Vacuum Casting.(III) Effect of Cold, Work and Annealing on two Electrolytic Leads, having 0.002% and 0.0005% Total Impurities respectively.1 Research Fellow, Dept. of Metallurgy, University of Melbourne.2 Proc. Aust. lnst. Min. Met., 1932, 87, 145.

Jan 1, 1934

By Fowke NC, Williams RJ, Hungerford F

In-seam, directional drilling has been implemented at Huntly West Mine, New Zealand as the most cost effective means of obtaining geological information at a level of detail and accuracy required for planning of longwall ("flexiwall") panels. No geological or geophysical technique tried at the mine prior to 1989 has been able to reduce geological risk to an acceptable level. Surface and in-seam seismic methods have not had adequate resolution. Obtaining the required knowledge via surface drilling would be prohibitively costly, and still not precisely locate or orient faults or the axes of seam "ridges and valleys".A total of 3543 m was drilled at an average of 67m/shift including setting up time. Unplanned delays totalled only 9.6 percent. Major re-interpretation of seam structure resulted from the drilling. Lateral and longitudinal panel grades have been defined. which should be negotiable with the Coalcorp longwall equipment.

Jan 1, 1991

Beneficiation of Nickel Lateritic Ore from Montes Claros de Goißs, Brazil Beneficiation is a key factor for both technical and economical aspects of industrial processing of nickel lateritic ores. A combination of comminution, classification and concentration stages are usually used to upgrade the metallurgical plant feed, thus resulting in both capital and operating cost reductions. This paper describes the testwork conducted on Montes Claros nickel lateritic ore in order to investigate the potential for upgrading. A comprehensive laboratory testing program included crushing, scrubbing, screening, grinding, gravity separation and attritioning, for both saprolitic and limonitic ore types from the Montes Claros deposit. The results indicated a clear potential for such an upgrade, which was later validated in a pilot plant program.

Sep 13, 2010

A 1991 survey of 48 mining companies, employing more than 24 000 employees, showed that disabling injury and disease rates continue to be the most common measurements of safety management effectivness in the Australian mining industry.Of the companies surveyed, 22 claimed to be making regular safety audits. Of these only two listed the improvement of audit scores among their goals for 1991.Influenced by loss control management thinking, some managers have expanded the scope of their safety programs to include all accidental operational losses adversely affecting mine profitability.Learning from their new experience with total quality management some managers are now recognising that successful safety management outcomes depend on the effective management of program inputs. They are thus turning away from measurements of accident consequences - the failures of the management system - to measurements of management control.The new focus of safety management attention is now on corrective actions before accidents happen.

Jan 1, 1992

By G McSpadden

At September 2001 the beneficiation plant at BHP Billiton Iron OreÆs Mt Whaleback mine is set to treat 9.5 million tonnes per annum (Mtpa) of iron ore, 40 per cent better than original design. This paper describes the steps, decision-making processes and innovations used to increase capacity at minimum cost. The plant was designed in 1979 to operate at 1133 t/h for 6000 hours per annum, treating 6.8 Mtpa. Sufficient suitable contact ore was unavailable and feed was finer than planned. The plant was designed with minimum surge capacity between multiple process units. It had never reached design capacity. In 1993 a study by Fluor Daniel to treat increased tonnage resulted in modifications to improve plant operations. Efforts to expand production by increasing reliability did not achieve the desired capacity. NJ Morrow (Pty) Ltd (NJM) conducted a technical audit in 1996 with process evaluation by Mineral Processors. Replacement of operator interface and PLC logic in 1997 made plant operation and diagnosis easier. Involving operators in logic development enhanced their plant knowledge. Fluor Daniel Simulation developed a simulation model of the process. Mineral Processors and NJM reviewed the model findings, recommended metallurgical improvements and developed preliminary designs and costs. BHP Engineering produced a detailed design with a cost estimate of $A34 million. After analysis and revision of the design, a $A10.4 million upgrade to 8.5 Mtpa was carried out. Detailed modifications to the process units, particularly the HM drum plant, allowed significantly higher capacities and improved metallurgical performance. The target capacity was achieved in June 2001. Further modifications are progressing to treat lower-grade ores.

Jan 1, 2002

By W Schauenburg

The increasing problems associated with the disposal of waste and the potential for use of by-products as underground filling material is a subject which is relevant not only to the coal-mining industry. The progressive scarcity of surface disposal facilities for by-products and waste has now become a problem in all sectors - not only for the mining industry. The considerable capacity offered by underground cavities which exists in various mining branches present an extremely promising potential in this context. The backfill process for coal mining developed by DMT in co-operation with Ruhrkohle AG make use of the cavities which are offered by the extraction of coal. It consists of several stages: The fine-grained by-products, such as sludge, filter cakes, fine refuse, ash and flue-gas cleaning residues are processed on the basis of specified formulations in metering, blending and pump facilities on the surface to produce pumpable pastes with precisely defined flow characteristics. On Walsum Colliery of Ruhrkohle AG up to 200 m3/h stowing paste is conveyed into the mine in pipes with diameter of 200 mm (8"). The delivery pressure of the pump operating on surface in conjunction with the hydrostatic pressure of the shaft pipe - amounting in total to as much as 25 MPa - makes it possible to convey the stowing material for a distance 12000 m underground up to the workings without any need for additional booster pumps. Via a pipe installed in the face, the paste is pressurised into the cavities in the specially fragmented rock in the mined-out zone well behind the support. Consistent use of stowage of caved-in goafs makes it possible to reduce surface settlement above the workings. Fires in the stowed rock are either smothered or completely prevented thanks to the exceptional air-tightness in the caved goaf and the cooling effects of the slurry stowage. The reduced danger of fire, the preventation of air-leakage and the positive effects on gas emission from the coal improve safety in the workings.

Jan 1, 1998

By J Bohm, B Csoke, I Tarjan

In process technology, especially in coal preparation, it is often necessary to have a continuous knowledge of the average density of granular material in order to achieve both quality control and process control. The paper presents a new method and means supported by laboratory measurements for the rapid, practically continuous, determination of the average density of continuously supplied granular material through frequent sampling.

Jan 1, 1993

By De Carvalho J

The average installed refrigeration capacity on South African gold mines has increased by about eighteen per cent annually for the past 15 years; both the number of installations and their duties have increased. One consequence of these large refrigeration installations is that careful attention must be paid to the system for distributing cold water. In these distribution systems, devices which minimize the temperature rise of the water delivered to the underground workings and which also reduce the pumping requirements for returning the water back to surface are used. In this paper the suitability of these various devices are examined and with the aid of a specially developed computer program their optimum operating conditions are determined. In addition the optimum combination of surface and underground refrigeration plants is examined for a hypothetical mine at various depths and the importance of pump efficiency on total distribution costs is discussed.

Jan 1, 1988

Feasibility studies in the development of mining projects are fundamental to most investment decisions. It is important that the issues addressed and the degree of detail involved in feasibility studies are consistent with the investment decisions to be taken. Emphasis should be placed on a thorough analysis of critical project parameters prior to detailed investigations being undertaken into other activities which are not relevant to the decisions at hand. Therefore, the issues to be decided upon should be influenced significantly by the stage of development of the project and by the reliability of technical and financial information used in the study. Some of the more critical parameters of feasibility studies are commodity prices, inflation rates and discount rates. Advice is given on the selection of these inputs and also on their application in the feasibility study as the project progresses through its various development stages. The feasibility study should involve not only a formal evaluation of project economics but also an analysis of all project related risks and a comparative analysis of projects competing in

Jan 1, 1983

Automation in underground mining enhances safety and leads to economic efficiency. In the past many efforts have been made on the automation of longwall shearer operation. With respect to the ultimate goal of automation, ie self controlled operation, coal bed boundary detection is one of the key problems. For longwall human labor is necessary in order to detect the exact position of the coal seam to be excavated. The authors present a sensor concept based on infrared technology and pattern recognition which will solve this problem. The very harsh underground conditions set high demands on the implemented sensors. The combination of infrared sensors and powerful processing algorithms is part of the innovative concept for automation of the new Eickhoff Bergbautechnik GmbH SL 750 shearer loader. The multi-sensor automation system EiControlPlus which is designed for the complete detection of the machine environment fills in the gap in the coal-excavation automation by building a recognition system that turns the shearer loader into an 'intelligent machine' which is capable of detecting the correct position of the seam to be excavated and thus enables human-free coal mining.

Dec 6, 2010

Diamond bearing deposits are extremely low grade and require large bulk samples to be tested to determine the grade and quality of the stones. The semi portable plants, for treatment of these bulk samples, have followed the development of commercial processes for diamond concentration. These processes included jigs and diamond pans, which have been largely supplanted by heavy media processes for primary concentration, due to the higher efficiencies in all size ranges. A number'of flowsheets including these processes are presented. The final recovery of diamonds from the bulk sample concentrates can be accomplished by rejigging, adherance to grease or by X-ray sorting. Flowsheets incorporating all the processes are presented. Two plants are described; one incorporating jigging, rejigging and hand sorting; the other using heavy media separation, and wet X-ray sorting.

Jan 1, 1984

Newmont Waihi Gold operates the Martha Mine open pit at Waihi, New Zealand and is developing the Favona Underground Project two kilometres to the east. The Company is exploring the Waihi district under eight exploration permits totalling 6300 hectares.   Martha Mine is scheduled to close in late-2006. The Company has instigated and funded a significant programme of community consultation to mitigate the effects of mine closure on the community and enhance effective participation in the selection and provision of appropriate community facilities post mining.   This paper provides an overview of current issues and future developments.

Jan 1, 2004

Yallourn brown coal and its characteristics have been the subject of innumerable papers and discussions. The Lurgi process adopted for the production of Towns gas by the gasification of brown coal has been described frequently in literature.The application of the Lurgi process for the gasification of Yallourn briquettes has naturally lead to some unexpected problems. Rather than attempt to review the whole field of experience gained in the first two years of operation of the gasification plant at Morwell, this paper attempts to describe two problems encountered, peculiar to the fuel used, and the steps taken in overcoming them.THE PROCESS AND PLANTTo clarify the conditions surrounding the problems, it is necessary to briefly describe the gasification and cooling processes and plant.Brown coal briquettes are gasified in a pressure generator, using a mixture of steam and oxygen as a gasifying medium. Crude gas produced in the generator is washed and cooled in the waste heat boiler and coolers. Figure 1 shows an arrangement of the generator and coolers. The gasifying medium enters the generator through a hollow shaft in the base. This shaft drives the grate, which has three purposes: (a) to distribute the gasifying medium into the fuel bed; (b) to extract the ash from the fuel bed; (c) to support the fuel bed.Briquettes enter the top of the generator through the coal lock chamber and the fuel bed is maintained at a reasonably...

Jan 1, 1960

By Crawford G. R, Wold M. B

The application of the hydraulic fracturing technique to the measurement of in situ rock stress from underground excavation is discussed; including relevant theoretical considerations, equipmenl details, experimental technique and analysis procedures. Examples of the application of the technique at three Australian coal and metalliferous mining operations are given. The results obtained from these applications are compared with corresponding results obtained from overcoring tests conducted in close proximity at each site. Generally good correspondence in a wide variety of rock types is indicated. Experience gained with hydraulic fracturing at several underground mining sites has indicated it to be a quick, cost effective means of gaining an understanding of the in situ stress field in sufficient detail for many mine planning functions.

Jan 1, 1990

By Woodcock JT

Successful chemical control of flotation requires practical solutions to many problems. A brief discussion is first given of those para- meters which can be controlled and those which it would be desirable to control. Suitable analytical methods for application to flowing pulp and to clear solution from pulp are out- lined in relation to on-line and off-line control. Practical problems of deciding where a measurement is to be made or a sample is to be taken and how the sample is to be prepared and presented to the measuring device are then considered. Equipment calibration and maintenance are considered in relation to the above factors.

Jan 1, 1978

By Marsham B, Baker D. C

The expansion of New Broken Hill Consolidated Limited (NBHC) concentrator necessitated the installation of hydrocyclone classifiers where rake classifiers had previously been used. Commissioning of the circuit and optimisation of circuit performance has highlighted problems related to classification of sulphide minerals. Testwork initiated to solve these problems has been used to develop cyclone models which have been incorporated in a ccnputer control strategy for the grinding circuit as a whole. The modifications to the circuit during the commissioning phase and the control philosophy are outlined.

Jan 1, 1983