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The Que River Mine is a small under-ground base and precious metals mine located in north-western Tasmania. Current production rate is 220,000 tonne/yr from reserves grading 0.37% copper, 7.1% lead, 12.2% zinc, 195 g/tonne silver and 3.4 g/tonne gold.Ore is mined using longhole open stoping techniques. Cemented fill is placed in primary stopes to permit safe and efficient recovery of pillars. The operation is trackless with both shaft and decline access from surface.Ore produced is trucked 40 km by road to be sold to the Electrolytic Zinc Company of Australia Ltd., for treatment at their Rosebery concentrator.

Jan 1, 1985

By Paine G

Kidston Gold Mines commenced mining in 1984 and currently mine approximately 10 million tonnes per annum of ore and waste using a conventional truck and shovel open pit method. The overall mine grade is a low 1.82 grams per tonne.The mineralisation is generally uniform within the ore zones and mining boundaries are staked out from blasthole assays according to pre-determined cut-off grades. Buffer blasting is necessary to minimise post-blast lateral movement of in-situ grade for digging control.The characteristics of the rock currently mined vary widely from soft oxidised to hard unweathered rocks. Blasting problems have been experienced during the initial mining phase in these harder rocks.

Jan 1, 1986

By Anderson KG

Multi-seam mining under the western portion of Lake Macquarie NSW commenced in 1982. Up to three seams separated by partings ranging from 10 to 30 metres are mined simultaneously by Newcom Collieries. A feature of these workings is the minimal bedrock cover, which ranges from 130 metres down to only 40 metres. "Surface" subsidence control has an over-riding influence on the design of the workings. Subsidence considerations govern both the selection of the mining method and the dimensioning of the workings. To date, workings have been designed in accordance with the "Wardell Guidelines for Mining Under Tidal Waters". These guidelines are tabulated and evaluated in the light of advances in rock mechanics knowledge and local subsidence data collected since the Guidelines were formulated in 1974. The local and regional stability of shallow workings designed according to the Guidelines is evaluated.

Jan 1, 1986

By Sheer T. J, Van Rensburg J P

The primary objective of this research was to address the demands imposed on self- contained self-rescuer (SCSR) performance dur- ing simulated escapes. The results clearly indicate that SCSR performance, apart from the inherent technological features, is a function primarily of the physical and anthro- pometric features of the wearer, and of the particular nature of the escape route. These factors consequently play a major role in the planning of any escape strategy, which may vary from mine to mine. It is therefore concluded that each mine would have to formulate its own escape strategy which in turn would depend on the choice of SCSR, and the particular escape Route.

Jan 1, 1988

By S J. Chen, N Jiang, Y S. Ding, F X. Li, D W. Yin, F Wang

This study assessed the deformation failure characteristics of rock-coal composites with different height ratios. Uniaxial compression tests were conducted using an acoustic emission monitoring system and XTDIC three-dimensional full-field strain measurement system. The results showed that with the increase in rock-coal height ratios, the uniaxial compressive strength of composite samples increased from 5.26 MPa to 14.61 MPa. The evolution of the deformation localisation zone of the composite samples is closely related to the initiation and propagation of the primary cracks in the coal samples. At the moment when the main fracture of the coal samples occurs, there is a large drop after the peak of the stress-strain curve of the composite samples, and the height of the rock samples increased to varying degrees, which indicated that the failure of the coal samples induced the rebound deformation of the rock samples. With the increase in rock-coal height ratios, the rebound deformation amount of the rock samples decreased from 0.042 mm to 0.008 mm, and the rebound deformation rate decreased from 0.210 per cent to 0.010 per cent. Meanwhile, the rock samples’ rebound deformation releases part of the elastic energy to act on the coal sample, further contributing to the destruction of the coal samples. Compared with single composite coal samples, the coal samples of the composite samples have much more failures. In addition, with the increase in rock-coal height ratio, the input energy density, elastic energy density, post-peak release energy density, and residual elastic energy density of the composite samples increased, the dissipation energy density decreased, and the percentage of pre-peak elastic energy density increased from 98.56 per cent to 99.86 per cent. These results revealed the deformation failure characteristics of rock-coal composite with different height ratios and provided a theoretical reference for understanding the underground dynamic rock failures.

Nov 29, 2022

By Kawatra SK

The incentive to control coal flotation circuits arises because of disturbances, from plant operating practices and variations in feed coal characteristics, which result in large amounts of fine coal being lost in circuit tailings streams and lower grade concentrates being produced. Additionally, the flowrates and compositions of con-centrates and tailings streams can have significant effects on dewater-ing brocesses. A universal control strategy for these circuits cannot be developed. Rather, three major groups of variables must be con-sidered during strategy development: coal characteristics; circuit design and operating practice; and the variables selected to control the process. The second. and third groups-are discussed in this paper and examples from studies in operating plants are presented.

Jan 1, 1985

Two examples of risk assessment and risk management in action are discussed. The first is in a management context in relation to Kingsgate Consolidated LtdÆs Chatree operation in Thailand. Kingsgate has conducted an over-riding risk management program to assess and manage risk across its complete business from the Sydney and Bangkok offices through to the Chatree Mine and the companyÆs exploration group. This example addresses how Kingsgate has applied risk management, particularly to the process operation, and the benefits that have been gained. The second is in an operational context in relation to Minara Resources LtdÆs Murrin Murrin operation in Western Australia. The subject is the methodology and outcomes of a risk assessment across the Murrin Murrin operation specifically to identify and assess risks with potential impacts from $1 M to $7 M. This section of the paper then shows how the outcomes of the risk assessment were integrated into MinaraÆs strategic plan to debottleneck the plant and increase nickel production.

Jan 1, 2004

The LeadtZinc Concentrator at Mount lsa treats all the lead-zinc-silver ore from the Mount Isa Mine and some of the ore from the Hilton Mine. This concentrator was commissioned in June 1966 and total lead-zinc-silver ore treatment was transferred from the Mount rsa's original No 1 Concentrator in May 1967. Plant capacity is around 5 x 106 t/y.There have been three phases of major plant modifications since commissioning:1. replacement and upgrading of the flotation section in 1979; 2. upgrading of the crushing plant and installation of a heavy medium hydrocyclone plant in 1983 for ore preconcentration, and; 3. doubling ball milling capacity and a further upgrading of the flotation section in 1992.Other developments have included the installation of flotation columns and Jameson cells.The evolution of milling practice since 1955 has been reported by Davey and Slaughter (1970), Bartrum, Dobrowolski and Schache (1977), Fiedler and Munro (1984) and Espinosa-Gomez el al (1989).Lead concentrate is smelted in Mount Isa while zinc concentrate and bulk concentrate (locally called Low Grade Middlings or LGM) are railed to Townsville and shipped to custom electrolytic zinc plants and ISP smelters.

Jan 1, 1993

By Fitter JF

Drilling and blasting practices at Groote Eylandt are undergoing a period of rapid change. Practices over the last ten years are reviewed and some specific blasting problems currently being faced are described. A move from percussion to rotary drilling is outlined, together with the reasoning behind a proposed return to ANFO from watergel explosives. A brief outline of the various firing patterns used is given, together with a description of the drilling and blasting recording procedures currently in use. Current and planned developments in drilling and blasting at Groote Eylandt are also outlined, emphasizing the success of wide patterns, fired in line with long inter-row delays.

Jan 1, 1982

By Sanders GJ

Coals from the Southern Coalfield of New South Wales treated in the Port Kembla coal preparation plants of Australian Iron and Steel Pty Ltd differ substantially in their characteristics. Knowledge of, performance not only enables comparison and promotes better control, but also provides the means for predicting results. Evaluation of performance of cleaning equipment has been made in terms of probable error (Ep.) Results for Baum jigs, a Chance cone, heavy medium cyclones and water washing cyclones are examined. The efficiency factors derived from the probable error are applied to the float and sink analysis, mathematically simulating operating conditions. This method is applied to the Balgownie seam. The Balgownie seam lies between the Bulli and Wongawilli seams in the Coal measures of the South Coast and mining on a large scale began recently in the Bulli area. It is known locally as the Four Foot seam and exhibits er difficult washability characteristics, due to a comparatively high middlings content. These properties and the tively high inherent ash make careful selection of cleaning equipment essential for optimum recovery. The prediction technique is used to determine the possible results when this coal is cleaned in the Port Kembla plants. Predicted values are compared with results from full scale trial washings demonstrating the validity and accuracy of the technique. Applications of result forecasting are listed.

Jan 1, 1970

By G C. Lukey, J S. J van Deventer

The disposal and subsequent encapsulation of mine tailings in a cost-effective and environmentally secure and responsible manner is one of the principal issues facing any modern mining project. A careful assessment of all options available for the capping and subsequent remediation of tailings is important because it can result in large capital, operating and closure cost-savings. For these reasons, the technology of geopolymerisation is receiving increasing attention for the stabilisation and solidification of waste materials produced from mining operations. The first part of the current study investigates the application of geopolymer technology to the capping of hypersaline mine tailings. It has been found that suitable geopolymeric materials which have satisfactory compressive strength, durability as well as low permeability, can be formed using between 60 - 75 per cent of mine tailings as the main ingredient. It has been established that geopolymeric materials have the ability to suppress dust generation and prevent salt precipitation on the surface of the mine tailings. The slurry-like consistency of geopolymers would promote efficient application procedures through established tailings disposal techniques. This is a possible close-out technique for hypersaline tailings storage facilities such as those commonly found in Western Australia, which meets both regulatory requirements and community expectations. The immobilisation of contaminant metals within geopolymers has been investigated in the second part of the present study. In particular, the leaching characteristics of Cu and Pb from geopolymeric matrices derived from different fly ash sources have been examined. Potential breakdown of each geopolymer containing metal contaminants due to the leaching of Si and Al from the geopolymeric matrix has also been investigated.

Jan 1, 2000

By Bradford NL

The Isa Mine of Mount Isa Mines Limited produces 5.1 million tonnes of copper ore and 2.2 million tonnes of silver-lead-zinc ore from sublevel open stopes annually. Extraction of the narrow, steeply dipping silver-lead-zinc orebodies requires a strategy quite different to that used in the massive copper orebodies. A range of blasthole diameters, explosive types and initiation systems gives the flexibility needed to adapt open stoping to a variety of situations. Hole diameters from 70 mm to 200 mm are being used, with lengths of up to 100 m common for the latter.

Jan 1, 1982

By Totterdell JM

The Permian-Triassic Bowen Basin and the Jurassic-Cretaceous Surat Basin evolved in a backarc tectonic setting behind an active convergent plate margin in eastern Gondwana. Several extensional (Early Permian; Eocene) and contractional (mid- Permian; Early Triassic; Middle-Late Triassic; early Late Cretaceous) intraplate deformational events are recognised in the basins. These can be correlated with similar events in the New England Orogen that was being deformed in the Late Permian- Late Triassic as a foreland thrust belt. The intraplate deformations were probably the consequence of plate interactions, including the accretion of terranes, at the ancient active plate margin, remnants of which now occur in New Zealand.

Jan 1, 1995

By Oxenford R. J

An important rutile-ilmenite-zircon bearing sand deposit was discovered by local farmers at Eneabba, 300 km by road north of Perth in 1970. These heavy minerals occur in a series of ancient strandlines and associated dunal deposits at elevations from 85 m to 170 m above the present sea level and are situated,30 km inland. The strandlines were deposited on wave- cut platforms in an ancient bay bounded by Mesozoic sediments during a series of regress- ions from a high sea level, probably during late Tertiary or early Pleistocene times. The immediate source of the heavy minerals in the Eneabba deposit is a widespread low content of those minerals in the nearby Mesozoic sedi- ments. The high-grade southern portion of the Eneabba deposit has been closely drilled and is now being prepared for production by Allied Eneabba.Pty. Ltd., a subsidiary of Allied Minerals N.L. This part of the deposit is 11 km long and up to 2.5 km wide. It is characterised by little or no overburden and the average depth of mineralisation, bounded by a 2.5 per cent heavy mineral cut-off, is 12 m. The water-laid strandline deposits at the base of the mineralisation are generally high grade, ranging from 20 to 60 per cent

Jan 1, 1973

By French D

In presenting this paper may I preface my remarks by recognizing the presence here to-day of the many delegates from the overseas mining communities throughout the world. That is to say - those delegates not representative of Companies resident in Australia. This does not mean that my comments following are directed solely to the Australian exporter - far from it. The Company which I represent is internationally based. The experiences we have had in dealing and negotiating with our good friends the mineral cargo shippers vary very little in any operational area. However for the purposes of this exercise this address is based on some of our experiences within the Australian trade scene with the emphasis on the fact that we believe it has application to all trading areas.

Jan 1, 1989

By Taylor GP

Mt Kasi in Fiji is a high sulphidation style of gold deposit exposed at a high crustal level. Individual alteration centres are localised at the intersection of cross structures within a through-going structural corridor, the Mt Kasi Fault System. A two stage alteration/ mineralisation model suggests that much of the high sulphidation alteration is derived from the initial rapidly moving gas-rich portion of the hydrothermal fluid. The gradual cooling and neut-ralisation of hot acid fluids by mixing with oxygenated ground waters forms the characteristic zoned alteration assem-blages which grade from cores of residual silica through silica-alunite to peripheral clays. The liquid-dominated phase of the hydrothermal fluid brecciates the competent, altered rocks and deposits sulphide mineralise-ation within the breccia matrix. High gold grades occur in the matrix-rich breccias and decline from the hydro-thermal fluid upflow to outflow zones.CSAMT (controlled-source audio magneto-tellurics) geophysics has been used to define the geometry of the alteration centres while strike slip movement on the major structures accounts for the dilational structural environment in which the ore hosting breccias form.

Jan 1, 1994

The Martha Hill project operates with a nett surplus of water, due to the catchment of rainwater on the tailings dam and the requirement to de-water the open pit mine. It is necessary to discharge this surplus, treated as required, to the Ohinemuri River which flows past the process plant.   The treatment plant, adjacent to the process plant, handles all effluent from the Martha Hill operation including water pumped from the mine, excess water from the tailings decant, and seepage from the tailings dam underdrains. To-date the plant has treated and discharged over 800 000 tonnes of water.

Jan 1, 1991

By Wright S

The feed to the Cockle Creek Imperial Smelting Furnace consists of mixed Pb/Zn con- centrates and lead sulphate-containing elec- trolytic zinc plant residues. Roasting was investigated as a means of desulphurizing the feed to less than 1%. Laboratory studies showed that two process streams were required in which concentrates containing 20% Pb were roasted separately from the leach residues. The residues along with fume from the roast- ing and a portion of concentrate were desul- phurized by means of the roast reduction reaction. Conditions were defined to give

Jan 1, 1986

By Kyle J. H, Misra V. N

The recovery of copper from a flotation concentrate using ferric chloride leaching has been investigated. The concentrate from the Horseshoe Lights Mine near Meekatharra, Western Australia, contained mainly digenite, pyrite and talc minerals. Over 95 per cent of the copper was dissolved in an acidified ferric chloride solution in one hour at 70¦C and ambient pressure. The pyrite and gangue minerals did not react. The leaching process was found to consist of four separate reactions and the shrinking core model was used to describe the process. The effects of particle size, temperature, concentration of FeCls, stirring speed and leaching time on metal dissolution were investigated. The apparent activation energies in the second, third and fourth reactions of leaching of copper concentrate were 28.8, 11.9 and 53.9 kJ/mol, respectively. The optimum conditions for the leaching of copper from the concentrate, within the range of conditions studied were: particle size 63 per cent minus 38 ¦m, a ferric chloride concentration of 1.48 M, a temperature of 70¦C, and a stirring speed of 800 rpm.

Jan 1, 1991

By R M. Anderson, S P. Pigdon

The production of stabilised backfill at mine sites commonly uses Portland cement as the binder. Calcined gypsum has cementing properties and is cheaper to produce than cement. This paper discusses the strength of fills stabilised with calcined gypsum. Laboratory tests were carried out on specimens prepared from tailings obtained from four different sites to allow for the wide variety of tailings found in practice. The results show that the gypsum-based fills can achieve a strength of 1 MPa using around two and a half to four times the corresponding amount of cement.

Jan 1, 1998