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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

By Peres EC

The flotability of monazite, zircon and rutile in the presence of sodium oleate, potassium octyl hydroxamate and a commercial hydroxamate was investigated through microflotation tests in a modified Hallimond tube. Zeta potential determinations in the absence/presence of collectors were performed in a microelectrophoretical cell. The microflotation testwork showed that, in general, the flotability characteristics of all three minerals are very similar. Commercial hydroxamate is, by far, a stronger collector than the pure potassium octyl hydroxamate. Electrokinetic studies indicated that the adsorption of collectors shifts the isoelectric point (IEP) of the minerals towards lower pH values. These collectors also are capable of changing the zeta potential values to more negative figures in the pH region above the isoelectric point. An increase of the conditioning temperature, generally, enhances the floatability of the three minerals. A depressant is required in order that selective flotation is feasible in the system monazite-zircon-ruffle. Sodium metasilicate is an efficient depressant for zircon and rutile and affects only slightly the flotability of Monazite.

Jan 1, 1993

By Arnold J. J

The design of a coal preparation plant using bore core data cannot be discussed without some reference to the wider considerations of design. A thorough knowledge of coal preparation processes and processors as well as ancillary equipment is essential if the coal properties determined from bore cores, are to be fully utilised. Whilst generalised information of processes is available from a wide range of publications and equipment suppliers for the intending plant designer, local operational experience must be taken into account where there are similarities. However it would be wrong to assume that satisfactory plant design can be achieved merely be repeating previous design parameters. A detailed examination of bore cores used in conjunction with well proven design 'criteria will identify important differences in design parameters without which efficient and economic plant/sectional sizing cannot be achieved.

Jan 1, 1977

Copper heap leaching involves both the simultaneous and sequential leaching of very large tonnages of ore over long periods of time. It is not unusual to be leaching three or four million tonnes over periods of 12 to 18 months. As a consequenc

Jan 1, 1998

By K-S Kim, C-Y Kim, D-G Kim

In tunnel construction or other underground construction, a detailed knowledge of the rock mass ahead of the face is essential for both safety and efficiency of work. Many tunnel collapses have been reported to occur because of lack of appropriate information, such as the geological conditions ahead of the tunnel face. One of the methods which can identify rock mass conditions is the application of drill monitoring data obtained from blasting drill holes, which can detect abrupt and unexpected changes in ground conditions, geological structure and the mechanical and physical properties of rock mass. This paper presents a new approach to how drill performance parameters can be used for prediction of geological conditions ahead of tunnel face. The predictions are based on monitoring the drill parameters of instantaneous advance speed, torque and tool pressure. In order to assess conditions ahead of tunnel face, tunnel seismic profiling (TSP) and a horizontal boring investigation were undertaken and the obtained data compared to the drilling data. The predicted results using drilling performance parameters correlated well with geological conditions ahead of tunnel face.

Jan 1, 2008

By Guo H

The importance of using disc cutters for rock excavation is reflected by their wide application in hard rock cutting machines such as tunnel boring machines and raise borers. The forces involved in the cutting process are those due mainly to thrust and rolling forces and are greater than that required by cutting picks. An interesting feature of cutting with discs is the formation of surface crushing, surface and sub-surface chipping and primary crack formation. Experimental, as well as analytical, work has been carried out to determine the optimum spacing between the disc cutters to control primary crack orientation. Wedge bit indenters were used to simulate disc cutters. The paper concludes by proposing a new approach to rock excavation by hybrid cutting based on controlling the primary crack Orientation.

Jan 1, 1992

The Tavua Power Proprietary Ltd. was created in 1936 for the purpose of supplying electric power, compressed air and water to the mining field.The original share capital was subscribed on a two-third:one-third basis by the Emperor Gold Mining Company Ltd. and Loloma (Fiji) Gold Mines, N.L. In 1940, Fiji Mines Development Ltd. (later changed to Dolphin Mines Ltd.) was admitted as a shareholder, and, in 1950, a further change occurred. The present shareholding in the Company is as follows:A central power station was decided upon to reticulate power and compressed air over the whole field and building commenced in May 1936.The original plant comprised three Belliss and Morcom diesel generating sets 770 b.h.p. 525 kW 3,300 V, 3 phase, 50 cycle; one Belliss and Morcom diesel compressor set 2,09'0 cu. ft. of free air per min. at 90 lb. gauge 300 r.p.m., and two small Ruston-Holman diesel compressor sets each of 525 cu. ft. capacity taken over from Loloma (Fiji) Gold Mines, N.L., and the then existing Koroere Gold Mining Company.BuildingThe original building was 130 ft. long by 47 ft. wide with an elevated switchgear annex on the west side from which a clear view of the engine room is available.

Jan 1, 1953

Mill liners provide the wear-resistant surface within grinding mills, they also impart motion to the mill charge, ie the grinding process, by providing the key between the charge and mill shell, and, at the discharge end, they remove the ground contents of the mill. As semi-autogenous grinding (SAG) mills have grown in size the process aspects of liner design and their impact on mill performance have become particularly important. While feedback from practical experience is critical to good mill liner design, increasingly sophisticated computer-based tools are being developed to assist in mill liner design.

Jan 1, 2007

In this paper presented are the criteria used when assessing the harmfulness of shocks affecting the buildings. Those criteria are based on the value of speed or accelerations of building vibrations. Presented is the scale of harmfulness of vibrations of Langefors and Kihlstrom, Bureau of Mines, and SWD contained in the Polish Norm PN-85/B-02170. The parameters of the mining shocks measured by the Lubin coal mine station were compared with the parameters calculated as per the correlations (regression curves). The average acceleration calculated from the correlations for eight measurements is only two per cent higher than the actual one. But the average frequency of vibrations calculated from the correlations for eight measurements is as much as 2.22 times lower than the actual one. In order to analyse whether that takes place in the whole range of the energy of shocks compared were the results of calculations from the correlations for various magnitudes of shocks and various distances from their epicentre with the results of the measurements. From that it follows that only for the shocks of the highest energies the lowering of the frequency of vibrations by two times causes movement from the higher zone of harmfulness to the lower one (for example from the IV to III). In the one-family houses in Lubin there were the damages that are characteristic for not only for the III but also for the IV sphere of harmfulness as per the SWD scale. That should be explained via further research and maybe it would be feasible to draw out a new correlation to determine the frequencies only for high values of energy of shocks and determine the preciseness of the acceleration and frequency correlations used presently.

Jan 1, 2003

Both innovation and excellence are desirable attributes of education, as they are also markers in the progression of the human race, but how attainable are they? The interaction of minerals and humanity provides a special insight into the development of both criteria, from the discovery that chert cuts, through the Bronze Age and the first use of metal alloys for implements, to using coal, oil and uranium as sources of fuel. However, there have been many hiccups along the way, where excellence in one respect has meant disaster in another. Examples are in the exploitation of asbestos, and in traditionally poor work practices in mining, both contributing to the widespread public belief that minerals and mining are ecologically undesirable. Yet is this perception based on the unrealistic expectation of innovation and excellence being simultaneous qualities of any given process? Common sense born of experience indicates that the journey from one, to the other, is usually a long and often tedious process, with much trial and error before excellence is attained. In our time, the partnership between academia and industry is the usual pathway to achieve it. Even so, we should take care that innovation does not become overwhelmed by the pursuit of excellence: as history clearly demonstrates, humanity depends upon both.

Jan 1, 2004

This paper presents a method for estimating the strength and stability of model coal pillars with bedding planes (weakness planes) inclination. The strength of coal relative to the angular difference between the principal stress direction and bedding planes is considered. The failure behaviour of model coal pillars containing weakness plane inclination by using servo-control Schenck Machine are shown. Uniaxial and triaxial compressive strength of coal specimens are investigated, and test results indicated that the strength of coal pillars depends on the weakness planes inclination with respect to the principal stress direction. However, it is shown that with increasing confining pressure, the effect of weakness planes inclination on the strength of the coal specimens is reduced. An empirical method is given for prediction the compressive strength of coal containing weakness planes inclination. The results of this method are compared with the experimental results and Jaeger theory. Finally, three well-known empirical strength criteria were tested against the triaxial test data for coal containing weakness planes inclination.

Jan 1, 1995

The amount of land subjected to coal surface mining in the United States has been reported at 1, 302, 000 acres (1). Latest National Coal Association estimates (1968) show that about 65, 000 acres are affected annually in the production of 186, 000, 000 tons of coal. Peabody Coal Company affects approximately 9500 acres annually in the ten States in which we are presently operating. Surface mining at Moura, Australia was begun in February 1961. In Marcy 1963, the Marion 7900 dragline with 35 cubic yard bucket went into operation and in 1967 the Marion 8900 dragline with a bucket capacity of 130 cubic yards was put into operation. In addition a third dragline, a 480W was added in 1969. It carries a 15 cubic yard bucket and is used to work areas that are too small to justify movement of the larger machines, In 1969 the Moura surface mine produced 3, 002, 774 short tons, and in 1970 3, 418, 933 short tons.

Jan 1, 1971

A review of publicly available coronial inquiries into fatalities that have occurred within the resources sector since the year 2000 reveals that a loss of corporate memory has been a contributing factor in 40 per cent of these accidents (National Coroners Information Service, 2010, Appendix B). With the highest levels of employee turnover within the Australian economy, increasingly complex operations and an ageing workforce, the management of corporate memory within the Australian resources industry poses a significant and often unrecognised safety risk.    The North Parks airblast of 1999 is used as a case study to highlight how corporate memory loss poses a significant hazard to resources projects and how such incidents will continue to occur if corporate memory is not effectively managed. Best practice from other industries is discussed to demonstrate how knowledge management systems can effectively work. This paper discusses how systems can be put in place within the geographically diverse resources sector, and how at the heart of any knowledge management system a culture of knowledge management needs to exist within an organisation.   The paper then discusses the importance of retaining key personnel and utilises findings from primary survey data collated in 2009 to show the size of the retention problem within the industry. From the data possible solutions to retaining key staff are proposed.   Finally the large and increasing role of contractors and consultants within the industry is discussed and methods of managing their knowledge are proposed.

Jun 1, 2010

The transportable moisture limit of a mineral concentrate (TML) is of great importance in the shipping of that material from Australian ports. Each year Australian mining companies incur substantial costs as a consequence of delaying shipments and/or multi-handling concentrates so as to comply with transportable moisture limits. Despite this there is a general lack of in-depth knowledge concerning factors that influence the parameter. Eight major Australian mining companies supplied sizing, specific gravity and TML data for their concentrates. Zinc, lead, copper and bulk concentrates were represented in their data. Estimated surface areas of the concentrates, as calculated from their normalised sizing data, correlated strongly with the reported transportable moisture limits. This high correlation prevailed in spite of the acknowledged limitations associated with the use of multi-sourced data and the adoption of simplistic approaches in the normalisation of sizing data and the estimation of surface area. Based on the broad range of concentrates studied, concentrate sizing data were concluded to offer potential as an alternative means of reliably estimating transportable moisture limits.

Jan 1, 1993

By Blake W

Based on preliminary computer model simulations and stability analyses, both longi- tudinal and transverse, large dimension, cut- and-fill rooms were designed for the parallel dipping ore layers at Kamoto mine. Full scale testing of the designed rooms showed that the rooms are stable and that the rock behavior is predictable. Ordinary waste rock was selected as the filling material because the fill was found to carry little load.

Jan 1, 1973

By M Pizey

After 60 years of operation, coal extraction at Solid Energy New ZealandÆs (SENZ) Strongman Mine, near Rapahoe is scheduled to end in early 2005. Up until 2003 the closure bond for Strongman Mine was only $930, and both SENZ and the West Coast Regional Council (WCRC) agreed that a more realistic level of bonding was required.   A conceptual closure plan has been developed by Golder Associates, and the cost of the work estimated. Closure includes decommissioning of equipment and facilities, rehabilitation and replanting of all disturbed areas and a period of maintenance and monitoring to verify that closure objectives have been met. Significant maintenance allowances are included to cover management of underground fire, subsidence and slope instability. These make up much of the potential ongoing environmental liability at the Strongman. All costs incurred beyond year 1 of closure are discounted to present value. Uncertainty in costs is addressed by Monte Carlo simulation, with an 80 % confidence level adopted.   A bond quantum of $3.0 million has been calculated for the first year of closure at Strongman. A three-year ærollingÆ bond is proposed. Progress will be reviewed annually, with the bond adjusted up or down accordingly. It is then renewed for a further three years. This allows for progressive return of the bond as rehabilitation objectives are met and verified. Similarly, if there are delays in meeting objectives, a proportion of the bond may need to be kept in place for a longer period than assumed. The level of bonding in place for the Strongman operation at any time in the future will therefore reflect the cost to complete the closure work programme.

Jan 1, 2004

This paper contends that optimisation of energy resources through active control and predictive simulation modelling is possible, and that such monitoring leads to large savings in the electricity costs of hot mines (where refrigeration has to be employed). In addition, active monitoring and control can positively affect the establishment of a safe, healthy and productive working environment. In the entire optimisation process certain guidelines were set to ensure that the requirements of the Mine Health and Safety Act were met (South Africa). Varying the quantity of air supplied underground by means of variable speed drive (VSD) fans is one of the crucial factors in the interactive approach towards the optimisation of ventilation, as is refrigeration and the pumping requirements associated with refrigeration. This article highlights the interaction between the amount of air supplied and the effect it has on refrigeration requirements underground. This article also considers the effect that this would have on contaminant control. Various tools are available for ventilation and cooling design for mining. A lot of these tools are based on the assumption of steady state conditions and do not take into account instantaneous changes in conditions, day-to-day, or hour-to-hour (such as for temperature and contaminants). They also do not take into account the optimisation of energy resources related to the creation of the acceptable underground conditions. With these tools worst-case and best-case scenarios are identified, and strategic decisions are made accordingly. Currently, the amount of the fresh air, the velocity of the air, and its general temperature in the mine are only changed when one production phase changes into another (or when unacceptable conditions occur as a result of poor design or neglect). This means that during a specific production phase (which can last for several months), there can be an oversupply, or undersupply, of energy resources, which will obviously affect the concentration levels of the various contaminants (through under or oversupply of air).

Jan 1, 2005

By K Gottliebsen

Many hydrometallurgical and chemical processes produce large amounts of acid waste. This is illustrated by the copper S/X-E/W process used at the Mount Gordon mine in North Queensland, which produces a tank house bleed in the form of a concentrated sulphuric acid stream. The bleed stream is necessary to remove impurities such as iron that decrease the efficiency of the electrowinning process. However, this bleed stream comes at a high financial cost due to large quantities of make up sulphuric acid required as well as the need to neutralise the bleed stream prior to disposal. The present work describes the approach taken to develop a solvent extraction process for the selective recovery of sulphuric acid from copper tank house bleed liquor. The proposed extraction system was investigated using a branched long chain aliphatic tertiary amine tris(2-ethylhexyl)amine (TEHA) as the extractant, Shellsol 2046 as the diluent and octanol as a modifier. Computer simulations were used to determine the optimum operating conditions for the recovery process. It was found that the process was able to selectively recover up to 90 per cent of the sulphuric acid from the copper electrolyte. This is recovered as a pure aqueous acid stream at a concentration of up to 130 g/L that can be recycled back into the tank house circuit or other areas of the process. The raffinate acid concentration was reduced from 180 g/L to as low as 18 g/L, significantly reducing waste disposal and the environmental impact of the copper process. The equilibrium data and simulation results were also compared with an alternative extractant, CYANEXR 923. Finally the efficiency of the TEHA extraction system was investigated on a pilot-scale in a pulsed perforated plate column. This information was used in order to scale the process for an industrial application. The same methodology applied in this case study could be used to provide innovative and cost-effective solutions to waste streams encountered in other hydrometallurgical or chemical processes.

Jan 1, 2000

By Sobek S, Lotzien RM

Although the conventional procedures for designing agitator flotation plants are well-known and reliable, little experience for designing modem pneumatic flotation plants has been gained up to now. A reliable procedure originating from graphic methods for the design of distillation columns is presented. Examples demonstrate on laboratory and semi-technical scale the application of this extremely practical method for designing a fly ash and a magnesite flotation plant.

Jan 1, 1993

By LaBrooy S. R

Crushing for the gold industry involves fine crushing and a degree of primary milling, and this presents new problems and challenges, partiuclarly on many of the new ore-bodies now being opened up. All of this calls for a better understanding of some of the basics of fine crushing and milling. Accordingly, in this paper the "typical" contemporary Australian gold mining operation is firstly delineated, in terms of representative ore types and typical crushing and milling tasks. Then some of the technical and economic basics related to fine crushing are re-examined, including: energy relationships in crushing and milling; concepts of reduction ratio; recirculating load controversies; and questions of realistic economics in crushing gold ores. The economics of the typical gold mining operation are shown to be rather marginal; not the lavish "bonanza" many may imagine. Likewise, crushing cost expectations are frequently quite Unrealistic.

Jan 1, 1987