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By A G. Grice

Surface disposal of mining processing wastes is usually perceived as an undesirable consequence of meeting societyÆs needs for metals and minerals. Environmental disasters associated with the discharge or storage of such wastes, though infrequent, can have very damaging consequences for the environment and the industry. Reducing or eliminating the potential for such events may be achieved by placing some or all of these processing wastes back into the voids created by the mining operations. Processing operations may limit or enhance the opportunities for using tailings and other waste products as a backfill material. Backfilling is a truly multi-disciplinary process and requires the informed involvement of mining, metallurgical, engineering and environmental specialists. This paper describes the range of fill types currently being used in Australian mines, particularly those utilising processing wastes as constituents. It focuses on how processing operations can affect the suitability of these materials for the various types of fill, the resulting fill properties, fill performance and costs.

Jan 1, 2002

By Braithwaite J. C

A brief summary is given of the applications of geochemistry on two areas in North West Nelson. It has been found to be an effective method for reconnaissance prospecting. Its particular advantage lies in areas which due to thick bush cover or ru

Jan 1, 1980

By Coppock BW

Sintering of lead and zinc concentrates is practised by Sulphide Corporation Pty. Limited to provide both desuiphurised lump sinter feed, for simultaneous reduction to zinc and lead in the Imperial Smelting Process blast furnace, and sulphur dioxide gas for sulphuric acid manufacture. From November, 1969 a 20 percent increase in production rate has been obtained through improvements in operating technique. A gradual increase in bed permeability was achieved by modifications to the feed mix conditioning equipment and by improving moisture control. However advantage could not be taken of the higher permeability to increase sulphur elimination because the hardness of the lump sinter decreased. Higher throughput, better quality sinter and more stable sintering conditions were however made possible by simultaneously: 1. reducing segregation and compaction in the sinter bed, by narrowing the discharge opening of the main layer feed hopper, 2. reducing the sizing of sinter returns to give a closer size spectrum of particles in the feed mix, and 3. increasing the sulphide sulphur content of the feed mix to give higher bed Temperatures.

Jan 1, 1972

The purpose of this paper is to discuss briefly the problems encountered in designing and sinking No 7 shaft, and to present the methods employed in the operation.The illustrations accompanying the paper show the details of the construction of the equipment used in completing No 7 shaft, consequently the descriptions appearing in the text are brief outlines only. Mineral leases Nos 7 and 8, held by the Broken Hill South Limited, comprise an area of 69.5 acres. The length of the holding is approximately 2500 ft.The western orebodies, which are the main producing masses, enter the property at the northern bonndary. Generally, the dip of the orebody is to the west, and the pitch to the south, but local variations occur and even a reversal of pitch has been noticed. The angle of dip is approximately 70 degrees and the angle of pitch 45 degrees.

Jan 1, 1932

The paper highlights the conceptual developments in rock mechanics applied to quantify the effect of bolts in the stabilization of joints and yielding soft rocks. NOTATION Aa = stress change after excavation Eä EE, Eä = moduli of intact rock, single joint and jointed rock Eb = elastic modulus of the bolt k, = normal stiffness of joint Ab = cross section area of the bolt A, = area of influence per bolt ab = axial bolt stress e, = axial strain of the bolt eä e,, ej, = strains of intact rock, joint and jointed rock Ai = area of the joint ,r+ = shearing resistance of the bolt (at the joint) a = normal stress at the joint plane aäa3 = major and minor principal stresses c;, 4i; = cohesion and friction angle of the joint 0 = angle between the bolt and the joint a = inclination of the joint to the vertical axis P = bolt density parameter u, = convergence of unsupported tunnel section u, = convergence of bolted tunnel

Jan 1, 1992

Structural assemblages of veins, shear zones, and wallrock alteration zones arising from fault-valve action on steep reverse fault systems are reviewed using observations from mesothermal gold-quartz lodes in the Archean Yellowknife, Abitibi, and Yilgarn greenstone belts of Canada and Western Australia, the Cretaceous Mother Lode system in the Foothills Metamorphic Belt of the western Sierra Nevada, California and the Victorian goldfield hosted in a folded quartz-turbidite succession of Paleozoic age in Australia. Despite differences in the host rock assemblages, the deposits have many structural characteristics in common. These form a useful exploration guide when re-evaluating comparable, but poorly described gold-quartz vein systems such as those in the Reefton area of New Zealand.

Jan 1, 1992

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 S S. Kanchibotla, D La Rosa, R W. Pesch

The Porgera Joint Venture and Dyno Nobel have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (SAG) mills by optimising the blast fragmentation. A number of test blasts were conducted during the period May 2000 to January 2002 and the ore from these blasts was campaigned through the mill. The data from these trials suggested up to 15 per cent increase in the SAG mill throughput with high energy blast designs. However, changes in ore geology (shape, structure and hardness) and potential ore dilution/loss and wall damage have raised concerns about the economic benefits of these designs over the entire orebody. The lack of a system to track the economic benefits of these modified designs has also compounded these concerns. PJV and DynoConsult, the consulting arm of Dyno Nobel have initiated steps to minimise the potential for ore dilution and wall damage resulting from these modified designs. DynoConsult worked with Julius Kruttschnitt Mineral Research Centre (JKMRC) to develop and implement a blast management system to track the quality of blast implementation and down stream process benefits. This paper discusses the implementation of the system and the results achieved to date.

Jan 1, 2003

Evolutionary changes to the original sizer concept are mild when compared to those which have taken place in the engineering standards embodied in today's commercially available machines. This paper examines the principles of sizer operation and reviews the development trends in new applications for this unique screen type.

Jan 1, 1978

By Thirnbeck M, Sione T, Petrie P, Leach TM, Mori W, Digan K, Harry K

Gold and lesser copper mineralisation are associated with porphyry-related vein systems periph-eral to two separate inferred intrusive centres north of Kainantu, Papua New Guinea (PNG). The intersection of NW trending structures, formed parallel to the Markham Fault, with NE trending transfer structures localise porphyry intrusions, and control vein distrib-ution.The Arakompa veins intrude pre-existing fractures in Akuna granodiorite, located proximal to an inferred porphyry. These veins are characterised by early quartz and later pyrite-chalcopyrite. Gold mineralis-ation is associated with Bi-Te phases in the sulphide veining. At Maniape, en echelon gash veins occur within the imbricate portion of a regional structure. Maniape is a high level carbonate-base metal gold system formed distal to the same porphyry source as Z ?-;4 kmmna

Jan 1, 1994

The mining industry has been slow at adopting the latest management philosophies from other industry sectors, such as manufacturing, and in retrospect, with good cause. With the plethora of three-letter-acronyms such as TQM, JIT, TPM and now, BPR each touted as the panacea for profit improvement, you wonder if you must choose one or attempt to embrace them all! In truth, each new insight into organisational behaviour bears some investigation. This paper looks at the underlying principles and elements of successful change strategies, and how several mining companies, including coal mines, in Australia, Chile and Canada, are applying these principles to their operations. These examples illustrate the need to think radically, and to view mining as an overall process delivering value to the customer rather than a collection of functional silos. They also show that often, a continuous improvement initiative is not enough when a fundamental redesign, a paradigm shift, is needed for a performance breakthrough.

Jan 1, 1998

The Australian bulk explosives industry has matured significantly over the last five years and it would appear that the rest of the world is following suit. This maturity is characterised by the technical sophistication of modem bulk explosives, an increase in the technical competence of the explosives consumer and a greater openness in the debate on the quality and performance of explosives. The principal mechanism by which these advances have been made is undoubtedly commercial competition in the market place although a new element, technical competition between manufacturers and independent professionals, has and will continue to play an important role in the development of the industry. The relationship between the explosives manufacturer and consumer is necessarily both complementary and competitive. This paper identifies the need for the consumer to take a more prominent role in the critical analysis of the performance of explosives and to use his commercial influence to direct explosives manufacturers at least in the direction required for the future technical development of the industry.

Jan 1, 1990

The paper describes the geotechnical as- pects of design and construction of two 12 m diameter concrete lined tunnels from the start of design to completion of construction. Prob- lems occurred due to delay in supply of essen- tial rock support materials from overseas and alternative methods using locally available materials were developed. Several major rock- falls and rock movements occurred and remedial measures are outlined.

Jan 1, 1981

By M Zhu, G Tranell, N Simkhada, K Jakovljevic, M Wallin

Silicon is a vital element in many products today, such as electronic components, solar devices, high-quality alloys, and many others. The growing global demand highlights the need for the development of sustainable production methods to meet this demand as an alternative to the current carbothermic reduction, submerged arc furnace (SAF) based process. An alternative to this is the aluminothermic reduction of quartz in a CaO-SiO2 slag, which not only reduces direct carbon dioxide emissions but also promotes the utilisation of secondary raw materials such as quartz fines, aluminium dross and scrap as well as secondary alumina (SA) from dross recycling. In the current study, the effects of SA and CaF2 additions to slag on the resulting metal composition and metal yield were explored. Results were compared with thermodynamic simulations using FactSage™ 8.1. Experimental results show that, in agreement with thermodynamic simulations, the silicon content of the alloy is increased, while the Ca is decreased for starting slags where CaO-SiO2 is partly replaced by CaF2. Similarly, the addition of SA to the initial slag results in an alloy with a higher silicon content.

Jun 19, 2024

This paper outlines the manner in which legislative control for tunnelling and allied operations has evolved, detailing Victorian experience. It examines the concept of mine managers as it relates to the industry and attemps to illustrate its benefits. The Victorian experience in relation to fatal and serious accidents is examined in detail, particularly in the allied art of trenching and examines the Krings system of trench lining support which is hoped will catalyse an increase of engineering expertise in this area. The paper concludes by demonstrating that safety awareness is not incompatible with production efficiency or economic viability.

Jan 1, 1981

By Mitchell D

In recent years the need to provide increased ventilation to improve environmental conditions rather than to dilute firedamp has led to increasing interest in the use of recirculation. Present UK mining law prohibits recirculation in ventilation, but it has been permitted selectively by exemption granted by Hm Inspectorate of Mines and Quarries. The conditions of use imposed by these exemptions to safeguard the safety and health of miners are examined in detail, dealing separately with primary and auxiliary recirculation systems.

Jan 1, 1988

Design of cemented fill in mining is often carried out without any consideration of the structure of the fill. The composition of cemented fills varies in the stopes due to the placement method, and the strength of the fill in the laboratory depends on the density, orient- ation, moisture content and drainage conditions. Within each stope there are definite zones and the structure of both cemented rockfill and cemented hydraulic fill has to be defined for each zone and the field conditions simulated in the laboratory. Structure also affects fill permeability and compressibility. From a study of the cemented fill in place, the effect of changes in the placement methods can be seen and then controlled to improve fill performance and economy. These features of cemented hydraulic fill and cemented rockfill behaviour are discus- sed and illustrated through reference to field and laboratory work undertaken at Mount Isa.

Jan 1, 1973

The present Pacific Ocean arose from rapid sea-floor spreading that commenced in the late Mesozoic, and continues to the present day. It started within what is here called the Medusa complex of seaways, basins and troughs with spreading ridges and volcanic arcs, that girdled the earth, including the Palaeotethys and Neotethys of Eurasia between Gondwanaland and Laurasia. Detailed mapping and analysis of palaeofaunas and volcanic arcs indicate that several seaways, rather than one or two, extended throughout Tethys, and into areas now occupied by the Pacific Ocean. The Medusa complex developed under a long sustained wrench regime, right lateral at least from New Zealand to Eur.ope, and saw the origin, maturation and closure of elongate and oval basins under erratic sea-floor spreading, in which no Eulerian pole of rotation remained fixed for long. The name Medusa stems from the analogy of snake-like writhing hair to the constantly shifting development of basins and orogens within the complex. The Indian Ocean split and opened up Gondwanaland concomitant with the later development and deformation of the Tethyan segment- of Medusa, whereas, to the east, the Pacific Ocean opened within Medusa itself, and dispersed Medusa around the rim of the Pacific through sea-floor spreading and strike-slip faulting.

Jan 1, 1987

By Jones A

Today there is a vast amount of information available relative to the performance of tunnel boring machines, and associated systems. The data referred to here consists of project reports, manufacturer's equipment literature and papers concerning almost every aspect of the excavation process. Why is it then, that many projects that employ full face tunnel boring machines (TBMs), on average perform significantly less than the peak performances reported in this industry?

Jan 1, 1993

By Cooke D, Large R

The Cambrian structure in the Mt Read Volcanics was produced by four deformational events: obduction of forearc-derived mafic/ultramalic complexes in the early Middle Cambrian, a middle Middle Cambrian extensional phase related to the post-collisional Mt Read volcanism and VHMS mineralisation, Middle Cambrian E-W folding, and Late Cambrian N-S folding and basin inversion. The major phase of VHMS mineralisation in western Tasmania is restricted to the very brief period of extensional tectonics within the middle Middle Cambrian. Within this period a N-S graben was produced with a complex series of transfer zones, largely striking E-W. Most VHMS mineralisation is restricted to the top of massive volcanic successions, with several mines close to Cambrian transfer structures. Many of the transfer structures continued to be active until the Devonian. The later compressional Cambrian events are not significant in localising orc formation. Within the Rosebery mine a complex pattern of minor Cambrian normal faults has a second order control on the distribution of the mineralisation.

Jan 1, 1997