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Data collected from payload management systems at a number of surface mining operations show significant variance. Heavily loaded trucks travel slower up ramps than lightly loaded trucks. Faster trucks are slowed by the presence of slower trucks, resulting in 'bunching' and production losses. A stochastic model was constructed to simulate a truck haulage return cycle of 12.5 km at a large open pit gold mine in the USA. For a fleet of 35 trucks, the best estimate of the benefit achieved by a sustained reduction in payload variance of 25 per cent is a throughput increase of 1.6 per cent, within a possible error range of 0.6 to 3.2 per cent. This potential benefit is worthy of further investigation by Continuous Improvement teams at large open pit mines. The model also indicates that, under the right circumstances, provision of an overtaking lane can provide throughput benefits of up to ten per cent, The feasibility of providing unidirectional haulage circuits within large open pit mines should be examined.

May 1, 2010

Coal water mixture (CWM) is a mix of finely ground coal with water and a small amount of chemicals. It is a new way of transporting and handling coal. CWM can be transported, stored and burned like fuel oil in steam generating boilers. It also has some environmental advantages over both oil and bulk coal. A group comprising Ube Industries Limited, Nissho Iwai Corporation (both from Japan) and Coal & Allied Industries Limited has been working in Japan and Australia since 1987 on a joint feasibility study into the production, transport and marketing of CWM from Australia to Japan. The group has been studying the development of a large-scale CWM plant on Kooragang Island at the mouth of the Hunter River at Newcastle, NSW. The project concepts and engineering plans for the CWM plant are well advanced and other studies related to the project are continuing.

Jan 1, 1995

Viking Holdings Ltd, a Todd Corporation company, is active in the mineral industry through operations, joint ventures and equity investments. Identification and management of risk is key to the success of the company. This paper discusses risk in general terms and in the context of Vikings activities. Reference is made to the current environment and the impact of risk and environment on profitability.

Jan 1, 1997

The capabilities of the three 61R and one 81R Robbins Raiseborers currently in use at Mount Isa are defined. Their applications in the development of ventilation and hoisting shafts, orepasses, escape routes, fill passes etc. are described and possible future uses of these and newer raiseborers at Mount Isa are examined. Problems associated with the use of raiseborers, together with ways of overcoming them are discussed. The impact of raiseborers on the mining operation is assessed in terms of new approaches to design and development, safety, cost and manpower efficiencies.

Jan 1, 1974

The Regional Development Council has initiated a project that aims to find better ways for further investment by extractive industry companies in sustainable regional and community futures. It will be undertaken through collaborative actions that bring together the resources of private and public sector stakeholders in regional Western Australia.   The broad objectives of the project are to: describe and analyse the current situation with respect to the impediments to regional communities being more self sustaining, assess the effectiveness of the current and possible future levels of investment by extractive industry companies in the sustainable development of communities in regional Western Australia, identify and demonstrate collaborative ways in which extractive industry companies in Australia and other countries can play an enhanced role in sustainable regional and community sustainability through strategic engagement and investment; and confirm the effectiveness of the collaborative measures in delivering sustainable outcomes for regional communities by way of attracting and retaining populations and enterprises in Australia and similar environments.

Jun 1, 2010

Carbonate replacement tin deposits in the areas studiedhere are genetically related to biotite granites. Biotite in the granites is distinguished by distinctive compositional features. High MgO content is found in biotite in the Renison Bell granite; high MnO and A1203 contents in the Gejiu granite; and high FeO content in the Xinlu granite. The compositional features of biotite in the granites are reflected in skarn minerals formed around the granites.Granites associated with these tin deposits are characterized by different accessory minerals. Magnetite-bearing granite in the Xinlu deposit is related to the andraditic garnet (andradite 40-45 mole%)-hedenbergite skarn, with tin mineralization occurring in the contact skarn only. The sphene-bearing granite in the Gejiu deposit is related to the grossular garnet (grossular 50-60 mole%, almandine 20-30 mole%) -salite skarn, with tin mineralization occurring in the contact skarn, as well as stratabound replacement orebodies in the distal skarn. The ilmenite-bearing granite in the Dachang deposit and the Renison Bell deposit is related to the grossular-diopside skam, with tin mineralization occurring 500-1500 metres vertically and 1.5-3 km horizontally away from the granite contact.

Jan 1, 1990

An efficient filtration plant can be designed only from an adequate knowledge of the filtration characteristics of the material to be handled; if these characteristics can be expressed in the form of an equation the work of design is simplified immensely. The literature of the subject contains numerous equations which have been developed by various workers to express their results, usually obtained from a 'Very limited class of material, and from moderately thick pulps. Such expressions have been found quite unsuited for use in the case of thin, very free filtering pulps.In 1926, Underwood put forward an equation having a general for m, and which, he was able to show, provided a satisfactory expression of the data obtained and published by a large number of earlier workers. This equation has been found a very satisfactory and useful tool for the study of a variety of filtration problems. As thel basis of the equation is of assistance to the understanding of subsequent discussion, a brief account of Underwood's derivation is given here.UNDERWOOD's FILTRATION FORMULAEThe following symbols are used:

Jan 1, 1932

By Alvarez A. R, Garcia H. l

A fuzzy expert system, DIME, has been developed, under Matlab v 5.1. to assess the coal and gas outburst risk in underground mining. Expert systems and fuzzy logic are powerful tools to manage information represented by linguistic statements,

Jan 1, 1998

By Andrew R. L

The Kintyre uranium deposit was discovered in 1985 in the course of following up radio- metric anomalies generated in an earlier air- borne survey. The latter survey was conducted primarily to acquire aeromagnetic data for diamond exploration and the uranium discovery was made during a subsequent campaign of base- metal exploration. CRAE commitment to the Rudall area for a range of commodities over a period of 13 years made a significant contrib- ution to the discovery of Kintyre. Other con- tributing factors included CRAE's multicommod- ity approach to exploration, management support and continuity in the geological team. The Kintyre uranium deposit (Fig. 1) is located on the northern margin of the Rudall Metamorphic Complex, 60 kilometres south of Telfer and 260 kilometres north northeast of Newman, in the Paterson Province of northern Western Australia. It is 700 metres inside the northern boundary of the Rudall River National Park (15695 sq. km) and lies between the Great Sandy Desert and the Little Sandy Desert (Beard, 1969). Intense weathering since the Permian has produced a subdued landscape around the deposit. Resistant rock types still retain an older plateau surface but it is incised by more recent streams. Other Proterozoic and Permian rocks form low, sometimes rocky, areas largely covered by aeolian sand.

Jan 1, 1988

The developments in hydrocyclone classification in the milling circuit at Bougainville Copper Limited are discussed. A major change in cyclone size and improve- ments in operating conditions have been made. Test work has been carried out to assess the classification performance of a modified Linatex cyclone, Wemco cyclones and a two stage cycloning circuit. The use of a scalping cyclone, to remove coarse material from the present overflow product for regrind, has also been investigated.

Jan 1, 1978

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 Szymanski J

The problems associated with underground mining continue to grow in size and complexity. As a result mine management is becoming aware of the benefits that can be achieved through the use of computer-oriented tools for system analysis. When such tools are employed in conjunction with benchmarking practices, the drivers of the system that lead to superior performance can more easily be determined. This paper discusses the use of the Simulation Language for Alternative Modelling (SLAM II) in the determination of the drivers of an underground room-and-pillar mining system. The mining operations included in the model consist of extracting, loading and hauling of the coal using continuous mining equipment in a room and pillar system. Equipment specifications and mining techniques used in the model are based upon current methods employed at the existing underground coal mines worldwide. The model developed is capable of adequately predicting the operational performance of the real world system from a statistical point of view. The results from the study show that computer simulation is an excellent tool for evaluating various mine configurations and for gaining a better understanding of the mining systems.

Jan 1, 1995

Any engineering firm hoping to do business in the modern world must understand-and take into account-the social and economic realities of client, country, culture, and community. If these considerations are ignored, any large-scale international development project is doomed to failure even before it begins. In this changing world, the distinctions between `developed', `developing', and `less developed' nations are more and more blurred. The so-called `less-developed' and `developing' nations are rapidly acquiring technology, an educated man- agerial and technical class, manufacturing capa- bilities, a growing spectrum of developed financial and raw materials resources, and a broad range of labour skills. These nations are establishing themselves as an integral part of the modern world, on an equal footing with other nations and with justifiable expectations for an ever higher standard of living and an ever better quality of Life.

Jan 1, 1978

The development of reliable and accurate solution sampling systems plus on-line atomic absorption spectrophotometers and voltammetric analysers at Pasminco Metals - EZ's (PMEZ) zinc refinery at Hobart, Tasmania, has led to extensive implementation of On-Stream Analysis (OSA) throughout the hydrometallurgical circuit. These systems complement industrial autotitrator and colorimetric analysers and with the comprehensive use of a powerful integrated Distributed Control System (DCS), provide extensive monitoring and control of all the important in solution' parameters for the plant. Samples can be left unaltered, or filtered or settled, to remove solids. They are then precision diluted and pneumatically transported to analyser shelters, where they are analysed for zinc, acid, copper, cadmium, lead, antimony, cobalt, nickel, mercury and ferrous, ferric and/or total iron. The range of analyses depends on the sample itself. The results are used for feed forward and/or feedback control of reagents where possible, or simple trend monitoring and out-of-specification alarming when closed loop control is not practical. The overall system reliability and accuracy is such that many daily composite plant samples are no longer analysed off-line. Operator sampling has also been reduced, and in two places, autotitrators with automatic sample pre-treatment have been installed for preparing and analysing samples collected by operators.

Jan 1, 1993

All aspects of the development of Ulan Coal Mines are covered - from a small pit pony mine in 1975 to an efficient mechanised underground and open cut operation today.

Jan 1, 1983

By Isokangas T. A

With some two-thirds of the production exported, coal mining prac- tices of the last few years in Australia have been much influenced by the decline in the price received. It became essential to improve efficiency and rationalise operations. Trends in underground practice vary. On the one hand many additional longwalls have been installed and most recently the results achieved by them have shown a significant up-turn; this may be correlated more with increases in equipment capacity than with utilisation which has altered little during the past six years. Varied constraints remain affecting cur- rent and future longwall operations. On the other hand a number of mines have been closed whilst others have sought to improve results by various installations including miniwalls, shortwalls, and use of continuous haulage and mobile breaker line sup- ports. All mines continue to review working practices.

Jan 1, 1988

The Cleveland Mine has an annual ore production of 400,000 tonnes at a grade of 0.79 per cent tin and 0.30 per cent copper. It is achieved by an open stoping method, mechanised overhead sub-level benching. The operation is trackless with a ramp access from all working places to the surf- ace. Broken material is loaded from the stope and development headings into diesel trucks and hauled to the surface crushing plant.

Jan 1, 1977

By R G. Barker, N Mortimer

In New Zealand, platinum group metals (PGM) occur in three main geological environments of economic interest: layered mafic igneous complexes, the Dun Mountain Ophiolite Belt, and in association with placer gold deposits. Most of the layered mafic complexes with PGM potential occur in the Median Batholith. These include the Longwood (Permian), Bluff (Permian), Riwaka (Devonian) and Rotoroa (Jurassic) igneous complexes. Exploration of the Longwood Complex discovered PGM associated with gabbroic rocks. Best assays to date include a 1 m drill intersection of 1 g/t Pt + Pd and float rock with 3.0 ppm Pt and 3.3 ppm Pd. The Greenhills complex at Bluff consists of basal dunite overlain by wehrlite and gabbro. PGM occur with chrome spinel in the basal dunite and Pt geochemical anomalies have been identified associated with the wehrlite-gabbro contact zone. The Greenhills complex has some similarities to Alaskan-Ural type complexes.Reconnaissance exploration in the Dun Mountain Ophiolite Belt has identified PGM geochemical anomalies, but no follow-up work has been carried out. During the late 1800s and early 1900s, PGM were recovered as a byproduct of placer gold mining in Southland. Placer gold prospects with PGM potential include the Waiau River, deposits flanking the Longwood Complex and some Southland beaches.

Jan 1, 2002

By Seedsman R. W

Good roads are essential in moving men and materials to and from the underground workplace. Coffey Partners International Pty Ltd (Coffey) has recently completed a underground coal industry funded project on underground mine road construction and maintenance. This paper discusses practical approaches to construction and maintenance of underground mine roads using transferrable civil technologies and innovative techniques. Mine pavements are generally low-cost (relative to civil roads), constructed to varying standards using locally available materials to best meet the mobility needs of the mine. Performance of pavements is thus largely dependent on the environmental conditions, quality of the available road making materials, maintenance policies and available resources. The paper will detail `what causes bad roads?' in various underground environments, available management strategies, construction and water control techniques, road maintenance and vehicle considerations.

Jan 1, 1995

By Ketteridge IB, Mulcahy DE, Quast KB

The long term energy demands in South Australia are such that there is a distinct possibility that one of the lignite deposits in the State will be exploited to feed a pulver- ised-fuel power station. Bowmans lignite deposit is the largest lignite deposit in South Australia and is considered to be a contender. The deposit is ideally situated (100 km north of Adelaide) but the quality of the lignite is poor (see Table 1). TABLE 1

Jan 1, 1984