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By Hosking IA, Mirkov P

Among the solutions currently being considered for improving traffic flow in Sydney are the construction of major road tunnels, principally the Eastern Distributor Tunnels, leading from the end of the Cahill Expressway to Drivers Triangle and South of Taylor Square and the Sydney Harbour Tunnel, which incorporates sections of driven tunnel at the northern and southern sides of the harbour. The Eastern Distributor Tunnels, known as Stages 2 and 3 of the Eastern Distributor Scheme comprise: Stage 2 - A south bound two lane tunnel from north of William Street to Driver's Triangle. The southern end includes two Y junctions (locally 3 to 4 lane widths) with exits into South Dowling Street, Anzac Parade and Moore Park Road. Stage 3 - A north bound, two lane tunnel from Taylor Square to Palmer Street just north of William Street. Further details of the Eastern Distributor Tunnels are given in the paper by Baxter, Chappel and Fishburn (1986) which is included in this conference.

Jan 1, 1987

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 Bruce P, Luyendyk

The South Island of New Zealand comprises a collage of distinct tectonostratigraphic terranes. Some tectonic models predict that these terranes formed on or near the margin of Gondwanaland. However, geologic evidence suggests that some of these terranes may be exotic. Over 400 samples from 30 sites were collected from the Brookstreet terrane within the Takitimu Mountains. The section includes the early Permian Takitimu Group and the late Permian White Hill Intrusive Suite. Over 80% of the rocks show a partial or complete regnetization in the present field due to recent acquistion of VRM. Although some remagnetization of the Takitimu Group occurred during the emplacement of the White Hill Intrusives, both early and late Permian direction have been isolated. These directions indicate a mid-latitude origin for the Brookstreet terrane, and suggest a strong clockwise rotation between early and late Permian time. A published paleomagnetic result from the younger, but related, Murihiku terrane suggests that the Brookstreet terrane was sutured to the margin of Gondwanaland by the late Triassic, or that the Brookstreet and Murihiku are two distinct terranes.

Jan 1, 1987

By R E. Hobbs, O Grabandt, C Das

Mine hoisting is carried out from depths of up to 4 km. At extreme depths, the ropes are so heavy that a large part of their capacity is employed in lifting themselves. Consequently, deep mines have an intermediate winding station. Even at lesser depths, the weight of steel wire rope reduces the possible payload. Of course, steel wire ropes have, over the years, demonstrated exceptional reliability and acceptable lifetimes. The use of steel is supported by well established operating rules and sound NDT methods. However, lightweight ropes made from synthetic fibres could be of great benefit to the industry, with the prospect of eliminating two-stage winding and substantially increasing the payload. Initial tests, in cycling over sheaves, have demonstrated that an aramid co-polymer fibre, Technora« is a potential candidate for this type of service. This paper presents results of testing carried out on aramid co-polymer and other synthetic fibre ropes. These results hold out the prospect of exceptionally long lives. Possible NDT methods are explored including optical fibres with optical time domain reflectometry or with Brillouin scattering, plus a method based on carbon fibre continuity. The introduction of aramid co-polymer ropes will require extensive testing and a program is proposed in the format of a Joint Industry Project.

Jan 1, 2005

By O Aydan, R Ulusay

Blasting is the most commonly used excavation technique in mining and civil engineering applications. Blasting induces strong ground motions and fracturing of rock mass in rock excavations. Particularly, high ground motions may also induce some instability problems of rock mass and structures nearby. Furthermore, it may cause some environmental problems due to noise as well as vibrations of structures near the populated areas. Furthermore, flyrocks is another major issue for the safety of people and damage to machinery and equipments when blasting is employed. In this study, the authors explore the ways how to estimate the ground motions as a function of distance, amount of explosive, number of holes. The ground motions were measured by stand-alone accelerometers developed by the first author and some empirical relations are developed. The effect of ground motions on the instability issues of benches such as sliding, toppling and rockfalls were investigated. Furthermore, the flyrock issue is investigated and some empirical relations to estimate the maximum distance of flyrocks from the blasting relations are compared and discussed. CITATION:Aydan, O and Ulusay, R, 2018. The ground motions induced by blasting in open pit lignite mines and its environmental effects, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 142–151 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Torres F, Cerda I, Gimenez P, Gonzalez G, Castelli L

Slurry density measurement, specially in cyclone feed streams, is fundamental to grinding circuit control. With the purpose of increasing the availability of such a measurement, the design of a soft-sensor in an actual grinding plant is addressed in this paper. The system is designed to substitute the momentary unavailability of the real density sensor, either because it has failed or because it has been removed for any other reason. The ARMAX model structure is determined using the stepwise regression method. Starting with a list of the candidate variables, the method selects, one by one, and in a systematic manner the variables which best model the measurement to be replaced, choosing them from the set of presumably correlated candidate variables. In this paper not only the single measurements are included in the list of candidates, but also combinations of such measurements having physical significance. A phenomenological model has been built with the purpose of determining these combinations. It turned out that in most of the cases the components of combined measurements having physical significance were selected by the stepwise regression method, instead of the single measurements. Actual grinding plant data is used to determine the model structure, to estimate the model parameters and to test the predictive capability of the developed soft-sensors. Good results are shown to be obtained during periods of up to 30 hours of the density soft-sensor operation.

Jan 1, 1995

Future depth and production limitations of an ore hoisting system are fixed by its initial design criteria. There is little scope to extend these limitations once installation is completed. Depth and production rate upgrades from the initial duty to the hoistÆs practical limitations require capital expenditure in stages, each of which can be defined when assessing the initial system design criteria. A means of presenting and assessing the design criteria, the limiting factors in each option and the relative present and future capital costs is necessary to arrive at a solution that delivers the best value to the mine. Application of this technique to recent friction winder installations and upgrades in the Australian mining industry is of particular interest; however, the analysis methods are also applicable to drum hoists. It is usual to specify a minimum hoisting capacity and depth, based on mine ore handling design and production needs. The final hoist depth and production rate are usually a result of the initial hoist design and hence it is useful from the outset to specify a required production versus depth envelope for the mine. Technical solutions can then be modelled within this envelope at their initial and final duties and a comparative analysis made against the cost of installing and progressively upgrading each solution. Understanding the factors that constrain each solution to a maximum production rate at a given depth is important, as the costs of overcoming limiting parameters such as rope tread pressure and motor power can be significant. The task of understanding and evaluating the options open to the hoisting system designer is simplified using this approach. Communicating the results of a multi-dimensional problem such as hoist specification is also made easier using the graphical methods inherent in the analysis.

Jan 1, 2005

By P Cheluszka, M Jaszczuk, P Sobota

This paper refers to a new idea of stereometry of cutting drums of longwall shearers designed to get medium and hard to mine coals. A new way to place picks on a drum enables to readjust a number of picks being in contact with the body of coal to shearer haulage speed. Owing to this a remarkable increase in depth of a cut within the low range of haulage speed has been obtained. On comparing operating characteristics a considerable reduction in the specific energy consumption has been shown when using the units machined as per the new idea, in comparison with the units produced in series.

Jan 1, 2003

The promotion of good standards of reporting of the valuation of mineral assets in- public documents has been of concern to professional mining industry bodies, the securities industry, and. Government regulatory bodies for some time. This concern led to the National Companies and Securities Commission Release 149 (1990b) which laid down standards for Expert Reports on mining and petroleum securities, and other assets. The formation of the Australian Securities Commission provided an opportunity for a timely revision of Release 149 and the Mineral Valuation Committee was established by The Australasian Institute of Mining and Metallurgy in 1991 to review the existing code, and to develop an appropriate new Code and Guidelines.

Jan 1, 1994

By Shibata Y, Shimizu R, Fukushima A

Kobe is divided by the Rokko Mountains, runn- ing from east to west. The southern section of Kobe is highly developed in contrast with the northern section, but big, new residential pro- jects like the Hokusetsu New Town and Hokushin New Town are steadily being developed. To handle future traffic between the two sections of the city, the double-tracked Hokushin Line, now under construction, will connect the Shin Kobe Station of the Kobe Municipal Transit (Kobe's subway system) to the Tanigami Station of the Kobe Electric Railway. The locations of Kobe city and Hokushin Line are shown in Fig.-1 and Fig.-2 respectively.

Jan 1, 1987

Getting it right is a very profitable outcome. Shareholders would ideally like to see their directors get it right all the time on the major economic decisions. But it is very difficult for mining directors to get it right all the time in such an uncertain environment. Primary decision-makers of companies with significant stakes in the mining industry should get it right much more frequently. The legal measures of evidence (beyond reasonable doubt and on the balance of probabilities) can be used to determine whether grade estimates (a key revenue variable) are realistic. The application of this approach can be far reaching. More frequently correct decision-making would result in more effective allocation of limited resources (capital and labour). In turn, this would result in higher financial returns and a more extensive mining industry.

Jan 1, 1994

By B BussiFre, J Molson, M Aubertin, G W. Wils

Waste rock piles containing reactive sulfide minerals can serve as long-term sources of acid mine drainage (AMD). Within these piles, many physical, geochemical and biological processes can contribute to the production of AMD. The flow of water, for example, depends on internal pile structure, which depends on the dumping methods used to construct the pile. In this paper, the internal structure and grain size distribution of typical waste rock piles are first reviewed with respect to their effect on internal water flow. A numerical model is then applied to simulate unsaturated flow within a waste pile assuming two primary waste materials, different atmospheric conditions and several geometric configurations. The simulations suggest that water movement can be controlled by introducing fine-grained material layers within the coarser host material. However, these layers should not be horizontal because they can lead to localised high-saturation regions as well as preferential flow favouring the production of AMD. A shallow slope towards the pile boundary may be introduced to force drainage to the outside while maintaining low saturation within the interior, thus reducing the production of AMD.

Jan 1, 2003

By K Rau

The overall success of a mining operation is directly impacted by the reliability and availability of mining equipment. Heavy-duty vehicles such as excavators and haul trucks are used for conveying of bulk material and improving such assets’ availability helps reduce costs, increase throughputs and improve safety (Ravande, 2022). If a mining operation’s key performance indicators (KPIs) are tied to operational performance, then overall equipment effectiveness (OEE) is an essential metric to track progress and to identify areas of improvement.

Sep 1, 2024

At the Nikkel og Olivin nickel mine near Narvik, Norway, Outokumpu has been the operator since 1993. The mine was opened in 1989 and in 1992 Outokumpu commenced operations to secure concentrate deliveries to Harjavalta's nickel smelter in Finland. Annual production is about 740 000 tonnes of nickel ore grading 0.5 per cent Ni, about 25 000 tonnes of nickel concentrate and about 2800 tonnes of nickel metal. All production comes from underground operations which makes Nikkel og Olivin AS perhaps the lowest grade underground nickel mine in the world today. Production is currently from one of two orebodies, which is known as the Western orebody. The Eastern orebody was worked out by 1995. During Outokumpu's operational period the Western orebody has been delineated and taken to production. The underground exploration and definition drilling involved about 15 000 in of diamond drilling, which was carried out during a nine-month period. Following this a feasibility study was undertaken and production commenced. Improvements were made to the mining methods. Previously the mine utilised open pit equipment underground and this resulted in an enormous amount of additional tunnelling. Grade control and ore delineation were previously based on sparse diamond drilling and all geological information was processed manually. The improvements included the use of underground sludge drilling to increase the amount of geological information, the of a new computer system for grade control and mine planning, new automated underground longhole drilling equipment and the of underground mining equipment which reduced the size of the drives. These changes produced a marked increase in the efficiency of the underground Mine.

Jan 1, 1996

The Ranger Project Area covers 78.6sq km and is approximately six km east-west by 14km north-south (Fig. 1). The area is known to con- tain two uranium orebodies, Ranger No. 1 and No. 3, two uranium occurrences, Anomalies 4 and 5 and three significant radon anomalies, Ranger 18, 19 and 48. The Ranger No. 1 and No. 3 Orebodies con- tain approximately 120 000 tonnes of U308 in highly chloritised metasediments of the Lower Proterozoic Cahill Formation. The orebodies occur as suboutcrop and exhibit significant radiometric anomalies. These occur within approximately 400m vertically of the projected unconformity with the sandstone of the Middle Proterozoic Kombolgie Formation. Oxidised and reduced uranium minerals occur in quartz-rich schists containing variable muscovite, chlorite and sericite and in the chloritic matrix of chert breccia. Secondary uranium minerals namely saleeite, metatorbernite and gummite associated with earthy iron oxides occur from the surface to 50m depth in No. 1 Orebody and up to 80m depth in No. 3 Orebody. Below the oxidised zone, uranium occurs as pitchblende finely disseminated throughout sequences of quartz muscovite chlorite schist up to 150m thick and as open space fillings in zones of structural deformation. The uranium-bearing schists directly overlie up to 300m of dolomite and magnesite containing minor interbedded schist units and are themselves overlain by approximately 2 000m of more micaceous schists of the upper part of the Cahill Formation. Regional metamorphism has occurred to at least amphibolite facies and has been followed by retrograde metamorphism to a greenschist facies equivalent. The metasediments are intruded by granitic pegmatites and dolerites. Uranium is associated strongly with chlorite of which there are at least five textural varieties. Not all of the various generations of chlorite have associated uranium. Graphitic schist horizons occur which are often less than one metre thick and discontinuous. These are best developed at the base of the quartz chlorite schist sequence where uranium grades up to 1 000ppm U may extend for several hundred metres beyond the main ore zone. Uran- ium is not common in the carbonate sequences and only occurs in chlorite segregations in disrupted zones. The unoxidised ore contains sulphides, mostly pyrite, which are low in abundance (

Jan 1, 1984

The grades of alluvial ore deposits are low compared with grades of hard rock mining. This factor, combined with other parameters of irregular distribution of particles, bedrock irregularities, size of particles, nugget effect, ore characteristics, and wet horizons, combine to place alluvial deposits among the most difficult to evaluate, and on which to establish an ore reserve with a high degree of confidence. With increased geological input, correct selection and implementation of sampling method, due regard to sample representativity and process design, these confidence levels can be achieved.

Jan 1, 1987

The Bowen Basin coal field is an important energy resource. A relatively small proportion is avail- able by open cut operations. Responsible men throughout the world have warned of the need to increase coal research immediately. Because energy is still available in abundance these warnings have not been heeded in Australia. The characteristics of the Bowen Basin coal make it a fairly difficult underground mining proposition and a significant research effort is required to solve the problems likely to be encountered. Both industry and government have responsibilities in the economic recovery of the maximum proportion of the resource and jointly funded research administered by existing organisations should be inaugurated forthwith.

Jan 1, 1976

By P H. Warton

It is proposed to construct a gold extraction plant at Matatoki, near Thanes. Ore to be processed at the mill will come from reopened and enlarged underground mines north of Thanes. The project has been described in some detail in environmental impact reports (Worley Consultants Ltd 1984, 1987), and is now at an advanced stage in terms of obtaining the required statutory approvals.

Jan 1, 1987

By Bilbrey J. H

Land utitized duxting the past 45 yeans by the mining industty in the United States con all puxpos ez to tal4 neatly 4 million sexes. Ob this axes, 13 pexeent is used bon dL4posal ob bLne -sized mtinexal wastes dL4eaxded by one milling plants. These wastes, especi- ally the inactive taLeLng4 ponds, xequixe some type ob stabULzation to pxevent aix and watex pollution. Because these tailings ponds axe locat- ed undex wideey vaxyting etLmctLe conditions and thetix physical and chemi- cal ehaxactexti5tLes axe not constant, many methods have been developed by the Fedexal Buxeau ob Mines and oXhex inve4- ttigatoxs box 4tabLtLzLng taLtLngs. This papex detfnea.e4 the magnitude ob the pxoblemz associated with the xeelametLon ob milling plant wastes and discusses the vaxtious methods that have been developed and used. Data bxom selected Buxeau o4 Mines taboxato&y xeseaxch pxojects and a s.abAJLzetLon field txtial axe pxesen.ed.

Jan 1, 1976

By Lunardi P, Pelizza S

The link between the Lecco bypass and major road SS36 (Italy) requires the construction of a double two-way tunnel (through the mount San Martino carbonatic massif). The tunnel excavating section is about 90 sqm through mount San Martino carbonatic rocks. The mountain sides are unstable and are often the scene of large collapsing landslides (tens of thousand cubic metres). The tunnels are very close to the mountain sides. The use of blasting induces vibrations which may reach the Lecco built-up area. With a view to avoiding such dangers the excavating operations were carried out in two successive stages: - opening a pilot tunnel, whose section is about 10 square metres, by a full face TBM to eliminate the more intense vibrations which are generated by the first opening charges; - successive enlargement by blasting.

Jan 1, 1987