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By A Tomsett, J Rutter

Ore control systems at Ridgeway have been designed to deliver gold and copper metal production through focussing on the ore characteristics that impact on mine and mill performance and ultimately metal delivery. This is achieved using data collection and management systems which allow data to be collected digitally with æat captureÆ validation routines. This data forms the basis of forecasting systems which aim to accurately assess local in situ and drawn ore characteristics. Physical attributes of ore such as draw characteristics, brow conditions and visual grade estimation are rountinely recorded. Ore tracking and accounting systems monitor gold and copper grade, copper mineralogy, host lithology and ore sizing. These have material impacts on concentrator throughput and metal recovery. Routine reconcilation and check sampling allow calibration of these systems.

Jan 1, 2002

The Government Mining Engineer of South Africa has decided to legislate that Self Contained Self Rescuers (S.C.S.R.) become a mandatory piece of equipment for all those persons proceeding underground. It is envisaged that: * employees in underground coal mines will be fully equipped with S.C.S.R.s during 1988; * those persons employed in gold mines during 1988/89; and * personnel in all other mines by the end of 1990. It is the intention of this paper to discuss the introduction of these auxiliary life support systems, and to give an update on current market developments.

Jan 1, 1988

By Hatherly P, Luo X, Balusu R, Gale W

Ongoing, collaborative research between CSIRO's Exploration and Mining and Strata Control Technology has resulted in a better understanding of rock failure mechanisms around longwall extraction. Failure has occurred further ahead of the retreating face than predicted by conventional longwall geomechanics theory. In some cases significant failure has been detected several hundred metres ahead of the face position with demonstrated influences of minor geological discontinuities. Shear, rather than tensile failure has been the predominant failure mechanism in the environments monitored. Validating technologies of microseismic monitoring and new face monitoring techniques have assisted the development of predictive 2D computational modelling tools. The demonstrated 3D consequences of failure has assisted in the ongoing direction of the project to further investigate these effects.

Jan 1, 1998

New South Wales mining legislation reinforces a systematic approach to safety management. It is now a requirement of all mines in the coal, metalliferous and quarrying sectors in NSW to prepare a Mine Safety Management Plan. The paper briefly outlines work currently being undertaken by the Safety Operations Branch of the NSW Department of Mineral Resources (DMR). The DMR is working proactively with NSW mines in the preparation and implementation of effective Mine Safety Management Plans. There is a growing realisation that a systematic approach to safety management, underpinned by the process of hazard identification, has real potential to improve safety in the workplace. The paper briefly describes the framework used in a current æmines education programÆ and its æduty of careÆ foundation. Particular attention is paid to the role of mining operators in the implementation of Mine Safety Management Plans and their expected behaviour in demonstrating compliance. One challenge is convincing some mining operators that they must adopt new ways of working. Safety Operations officers are often reminded of the need to translate Mine Safety Management Plans into practical safety systems during audits and inspections of mines and through investigations into accidents and incidents. To have a real effect on the mineÆs safety performance, using these systems must be a normal way of going about a dayÆs work for all persons who work at the mine: not a safety manual collecting dust on the mine managerÆs bookshelf. Mine Safety Management Plans are important to mining operators. Not only will positive involvement in the development and use of safety systems ensure they meet their obligations under mining legislation, but it will also help prevent themselves or their workmates being injured or killed.

Jan 1, 2002

A good blending system is one that ensures that a plant can cope with the amount of grade variation that it will encounter. Prediction of amounts of variation that will be encountered on time or tonnage scales that are important should be regarded as an essential part of the planning of mines and plants. In some cases, the natural amount of grade variation when ore is mined and handled in the cheapest way will be acceptable. In other cases, it is necessary to understand the effects that various ore-handling processes have on amounts of grade variation at various scales and to design a blending system with considerable care. Blending tends to matter more when plants are sensitive to many aspects of grade. It can be very difficult to find the best compromise between capital cost and the amount of grade variation. In these cases it is important that ore blending options be considered carefully as part of the planning of mines and plants. Failure to make plans that consider likely amounts of variation can be very expensive.

Mar 1, 2010

By Duncan B

Shortwall continuous mining as first introduced at Burwood colliery, and currently being used at John Darling, Lambton, and Corrimal collieries, is a method of coal winning which was pioneered in the Newcastle district. The system uses individual hydraulic self-advancing chocks for roof support and the coal winning operation is by continuous miners and shuttle cars. Where physical conditions are suitable the system provides a safe, efficient and economically viable basis for pillar extraction. Shortwall operations have been conducted successfully in the Victoria and Dudley seam, near the coastal fringe of the Newcastle district and are now being tried out in the more difficult conditions of the Bulli seam in the Illawarra district.

Jan 1, 1972

By J Herbertson

æZero waste steel making productionÆ has already been the subject of several studies and also the successful result of some companies. Regarding waste and by-products, slags are the largest in terms of weight, although among the least hazardous. All steelmakers around the world are presently looking into profitable solutions, according to their local conditions: environment constraints, available markets, and mode of operation. Today the major technical methods of slag value capture include different levels of magnetic separation and screening to remove entrained steel, for production of aggregate in civil works. A survey of different retrieval processes shows that pyrometallurgical processing of steelmaking slags will increase the recovery ratio of iron and other metals. In the process, the remaining part of the material, a mixture of metallic oxides, can be easily transformed into hydraulic binder such as cement. Can steelmakers consider the slag as a co-product, and not only a waste or by-product? The ability of pyrometallurgical processes to treat other wastes and by-products generated in the steelplant is an opportunity for the steelmakers to reach the æzero waste productionÆ status. A technical survey of the experiences and possible solutions of pyrometallurgical processing is presented as well as technical descriptions of technological, economical and profitability analysis in relation with foreseeable markets.

Jan 1, 2002

Knelson concentrators are commonly used to recover fine liberated gold in gold processing plants. The decision to employ a gravity gold circuit consisting of centrifugal devices such as Knelsons is primarily taken on the results of GRG tests, among other considerations. While the GRG test is considered a material characterisation test, which is useful in the design stages, its use in evaluating the performance of an existing unit is questionable. The problem is exacerbated by the fact that it is time consuming and costly. This paper examines the validity of the GRG test for performance evaluation and discusses alternative test work that can be performed to evaluate the performance characteristics of an operating machine. Principles that are useful in selecting optimal operating parameters, such as optimal fluidising water flow rate for a given ore/machine combination, are also discussed and illustrated with laboratory and plant data.

Jan 1, 2007

By B Murphy

Traditionally comminution optimisation has been focused on energy minimisation, whereas flotation optimisation has been focused on recovery improvement. One of the largest, if not the largest, operating cost over the life of a flotation circuit is electrical energy. With increasing pressure on operators to lower production costs and the cost of energy increasing, reducing the energy consumption of the flotation circuit can be beneficial to site economics. This paper reviews the use of energy by mechanically agitated flotation machines and discusses the measurement and benchmarking of energy consumption in modern flotation concentrators. Opportunities for improving flotation energy efficiency are also identified.CITATION:Murphy, B, 2013. Flotation energy consumption and opportunities for improvement, in Proceedings MetPlant 2013 , pp 399-412 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

The Prospect to Pipehead Tunnel is a component of the Sydney Water Board's multi-million dollar Drinking Water Quality Program to improve the quality of Sydney's potable water supply to meet revised national health guidelines. The tunnel project involves the construction of seven kilometres of 3.9 metre diameter machine bored tunnel which is to be lined with a three-metre diameter steel liner. The paper describes the fully integrated planning and design approach and management technique used to enable this major project to proceed to meet the requirements of a tight construction program.

Jan 1, 1993

By Hamilton LH, Campbell PB

Since fundamental research in applied coal petrography is carried out mostly on polished surfaces, backscattered electron microscopy is most applicable for studying coal in the SEM. By employing this technique coal macerals can be easily identified , and information on the relations between maceral groups, mineral matter and trace elements are highlighted by grey level contrasts. This type of information is valuable in coal technology and cannot by normally revealed by the light microscopy (e.g. the distribution of inherent mineral matter).

Jan 1, 1989

By Gillies A. D S

Technology transfer is a vital requirement for increasing national capability of coal mine production in Indonesia. The term can cover the introduction of new equipment, facilities and processes and approaches to training and education. Constraints on technology transfer within the Indonesian coal mining industry are reviewed. The contributions that foreign companies working within the industry can make are discussed. It is concluded that the development of major Indonesian coal mines needs input of advanced foreign technology. The foreign mining companies are investing significant capital in operations and are permitted to import outside expertise due to some lack of national skills. Expatriate employees are expensive and have a direct effect on profitability. The success of any replacement program of foreign employees is dependent on technology transfer. There are statutory Indonesian Government directions to reduce dependency on foreign expertise over time.

Jan 1, 1995

By Lyman G. J

Magnetic separator operation in the recovery of magnetite in heavy medium circuits was studied by conducting a series of tests on a full size wet drum magnetic separator.The significant operational variables were found to be feed pan clearance, squeeze pan clearance, dry magnetite feed rate and separator drum speed. With feed and squeeze pan clearances optimized for typical primary separator operation, magnetite loss and concentrate specific gravity were found to be related in a regular manner to dry magnetite feed rate at any drum speed.A two component model of magnetite loss is proposed, relating total magnetite loss to losses in the feed pan and squeeze pan zones. The experimental curves relating magnetite loss to dry magnetite feed rate at the various drum speeds are interpreted in terms of the two component model.The magnetite particle size distribution in the separator was also examined. The tailings magnetite was found to be finer than the feed magnetite only when the dry magnetite feed rate was low, or immediately following the introduction of a new charge of magnetite when the separator was fed at an intermediate dry magnetite feed rate.

Jan 1, 1983

By Durao F

A multi-layer feed-forward neural network was trained (using the error back-propagation algorithm) to learn a subset of rules designed to stabilise the performances of the copper flotation section of a complex sulphide processing plant and then tested in order to evaluate its expert performances. Two types of neural networks were compared: the classical ones, fully connected between one layer and the adjacents (with different architectures), and entropy networks, partially connected and generated according to a methodology that simplifies its building up. The advantages and drawbacks of both were analysed and compared with classic (rule based) expert systems.

Jan 1, 1995

Landscape interpretation, geology and mining history are being successfully used to explore options for sustainable community tourism product development. Recent work by the author in Europe and Australia has indicated the value of adding and producing interpretive information about mine and quarry locations û both active and inactive. This work has allowed for the branding and development of new sustainable community tourism products based on the landscape, folklore, mine and geological heritage. Communities in rural areas are seeking new opportunities to sustain their local economies. Using a relatively new phenomenon called geotourism as a starting point, they have developed themed products connected to walking/cycling guides, interpretive panels and visitor centres. These themes can be linked to geology, archaeology, botany, local history and to industrial heritage sites such as old mines, to generate local employment. This new geotourism approach has successfully brought a new and greater audience to discover the value of geology and mining history. Communities have established a unique place for themselves within the tourism marketplace using the geotourism brand. Other communities with an established tourism product are also now using geological and mine heritage via geotourism to rebrand and meet changing global trends. The geotourism approach has allowed for positive collaboration among communities, service providers, local and government authorities to channel tourist revenues into rural communities. The pooling of resources under the banner of geotourism has led to cost-effective marketing, targeting and promotion of products using multimedia and web sites. Geotourism has emerged strongly in Europe, North America and China in the last decade. The Australian minerals industry now has an opportunity to implement this new branding concept to assist and benefit the communities in which they run their activities. Communities can also take advantage of the potential to develop a sustainable geotourism business around a past or present mineral industry in their vicinity.

Jan 1, 2009

By K Uchino, M Inoue

Self-potential anomalies are generated by fluid pressure gradient, by temperature gradient or by chemical gradient. On the basis of this principle, a new technique is proposed to locate the fire source of spontaneous combustion of coal by the self-potential method. In order to investigate whether this method can be applied to locate the spontaneous combustion of coal in practice, surveys of self-potential distributions were undertaken in a coal waste pile undergoing spontaneous combustion. The results showed that there is a negative centre of the electrical potential distribution in the measurement area. The potential in this centre is about 140 mV lower than that in the surrounding area. Moreover, the negative centre of electrical potential distribution almost overlaps with the high temperature zone. Therefore, it is concluded that it is possible to locate the heat source by the measurement of self-potential distribution.

Jan 1, 2005

Grey River Gold Mining Ltd commenced dredging alluvial flats in the Grey River Valley in 1989. Previous drilling indicated over 100 million cubic metres of gravels with some 90 per cent of the gold in the bottom seven metres. The dredge built by Rahco, Spokane, was innovative in a number of aspects but particularly in the fact that a separate ladder with a cutter and pump was used to strip the overburden and a bucketline to mine the gold bearing wash below. Metallurgical studies and exploration were initiated when the project commenced. Leasing and environmental considerations were investigated and action taken. While progress is being made, the operation at this stage is not meeting required production and performance. Main problems have been with the stripping system and wear.

Jan 1, 1990

By McLennan T, Howells E, Zastawny H, Watt J. S

Nuclear techniques have been used to determine the solids weight fraction (W) and ash content of (fine) coal in slurries independent of voidage variations. The method is based on the correlation between W and the hydrogen concentration Hsl (wt/wt) of the slurry. Hsl is determined by combining measurements of neutron moderation and ?-ray transmission. Both Wand ash content are determined by combining the above measurements with the ash-sensitive measurement of X-ray backscatter compensated by a measurement of iron K X-ray intensity.The nuclear analysis system, called the SIRO coal slurry gauge, has been proved in a six-week plant trial at the BHP Steelworks washery at Newcastle, NSW. Several probes, each containing a radioisotope source and scintillation detector, were immersed directly into the coal slurry in the feed box upstream from the bank of flotation cells. For 140 samples W, ash and voidage varied in the ranges of 0 to 13 wt percent, 26 to 41 wt per cent and 0 to 4 vol. per cent, respectively. The r.m.s. difference in solids weight fraction, determined by probe measurements and conventional assay, was 0·52 wt per cent. Ash was determined with an r.m.s. difference of 2·0 wt percent in the coal. Better sampling techniques were used in the last half of the plant trial, and r.m.s. differences were 0.35 wt per cent solids and 1·5 wt per cent ash.

Jan 1, 1986

By N J. Grigg

Gekko Systems has developed an underground pre-concentration plant (Python) to reduce mine operating costs. Many ores liberate favourably using either high pressure grinding rolls (HPGR) or vertical shaft impactors (VSI). Using these comminution circuits for mineral liberation; rather than for the final recovery process and by utilising a high mass pull, high recovery process route (gravity/flotation), a narrow, low head, compact processing plant was developed that can sensibly be operated underground. The Python underground processing plant can provide a number of advantages for narrow vein mines including lower haulage costs, improved mine call factor and lower operating costs. The focus on fine crushing reduces the power requirement of the plant to approximately 8 kWh/tonne. The Python underground processing plant has been designed to be towed down the decline or lowered down a shaft, and is capable of being installed in sloping, non-linear drives for placement close to the working face. The overall benefit to mining companies of this concept has been estimated to be a saving in mining costs and a significantly smaller environmental footprint.

Jan 1, 2008

By T Bednarz

The present work proposes a distributed collaborative immersive virtual reality framework for prospective applications in the mining industry. A human-centered approach is described, with people being placed in the central position and surrounded by tasks that are to be carried out. Those tasks can be then achieved through synchronous or asynchronous communication, interactions using properly constructed user interfaces, virtual and/or augmented realities and computer vision. Several examples of such arrangements are presented. One of the applications facilitates an e-learning experience by providing a very familiar object – a book – as a target for users to interact with. Importantly, this system has the potential to provide an ‘enhanced’ teaching medium, as humans tend to remember events/situations better when they experience those events in person, when the immersive factor is involved. The immersive virtual reality environment enables a user to interact physically with various 3D objects and experience behaviours, which in turn reinforces the idea that doing leads to learning. This prototype system can be implemented as an efficient and cost effective e-learning and training platform for different engineering domains. At another level, the same technology can be used in the tele-operation of mining equipment for the future mine.

Nov 22, 2011