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By Kerr M. H, Slaughter P. J

Design of the new cemented hydraulic fill plant was based mainly on experience with a succession of previous fill plants. Two stage cycloning of combined concentrator tailings was introduced. Design of the two stage cyclone configuration was assisted by computer simulation of cyclone performance. Cementing additives, namely Portland cement and ground copper reverberatory furnace slag, drawn from bulk storage, are pre-slurried prior to mixing with hydraulic fill. Quality control of fill being sent under- ground is achieved by a series of automatic control loops. Plant instrumentation was given prime consideration during the design phase. Inventory checks of all mass flow metering equipment are made at regular intervals. Fill is pumped to boreholes at several locations. Details of the equipment and operating procedures for the plant are Discussed.

Jan 1, 1973

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

By Thuli AJ

Copper concentrate from Bougainville's copper mine located on the west slope of the Crown Prince Range on Bougainville island, is pumped 27 km to the filter and drying plant at Anewa Bay for preparation and storage prior to shipment to overseas customers. Prior to shipment the thickened concentrate slurry is passed through a test loop to check that its consistency and pH are acceptable for transportation through the main pipe line. The Bougainville pipe line is unique since it is the world's first copper concentrate system. where slurry is pumped an appreciable distance against a high head,

Jan 1, 1975

By F J. Rios

In the eastern high-strain domain of the Quadrilßtero Ferrffero, Brazil, hard and soft high-grade hematite ore may occur as schistose bodies in shear zones mainly related to the Cambotas-Fundpo thrust system. These orebodies are almost entirely constituted of oriented specularite platelets that develop both as a product of crystal-plastic deformation of hematite and solution-precipitation processes. Both mechanisms interact in the partitioning of the strain, while solution-precipitation is responsible for the precipitation of hematite and localised leaching of silica resulting in the formation of syntectonic ores. The analyses of fluid inclusions from specularite crystals of the Conceitpo and Timbopeba deposits, located in the northern and southernmost areas of the eastern high-strain domain of the Quadrilßtero Ferrffero, were studied using infrared microthermometry and Synchrotron x-ray fluorescence. The results indicate the participation of highly saline aqueous H2O-NaCl fluids containing other additional cations (Ca, Fe, K and probably Ti) in solution and homogenisation Temperature (Th) averaging between 130¦ - 190¦C. However, the partial fusion of metastable saturation phases indicates crystallisation temperatures of approximately 400¦C. The mineralisation process produces high-grade orebodies as well as Fe-rich specularitic itabirites that are explored in that area. The shear zones are related to thrust faults mapped and interpreted as related to the PanAfrican/Brasiliano Orogeny that affected the Quadrilßtero Ferrffero, thrusting the Paleoproterozoic platform sequence of the Minas Supergroup over Mesoproterozoic quartzites of the Espinhato Supergroup. They intersect and even overprint an early metamorphic and tectonic fabric of Paleoproterozoic age (Transamazonian Orogeny). The geological and fabric relationships lead to the conclusion that the fluids involved in the mineralisation were most probably of external origin, of still unknown source (possibly igneous), during the closure of the Spo Francisco Craton.

Jan 1, 2005

By Hyde L. J

Blasting is one of the available technologies to be employed in underground excavation systems. In many instances it can be the only technology which is suitable. The recent moves towards more mechanised working systems is resulting in a reduced awareness of new blasting practices and technologies on the part of many excavation engineers. Recent developments in blasting systems can be utilised to significantly improve operating efficiency, reduce total cycle times, better comply with regional environmental constraints and reduce the total cost of underground excavation. Blasting is and will remain, a very adaptable and exciting alternative which is far from boring.

Jan 1, 1987

By Dunne R, Defilippi J

Dump leaching began at Teller in late-1988 at a rate of 4 MTPA and has been progressively expanded to the present rate of 10 MTPA. Teller's on-going commitment to dump leaching is driven by the amenability of gold ores to the process and the availability of large tonnages of low grade gold ore. The sequence of evaluating ores for dump leaching involves rolling bottle tests on coarsely ground ore, followed by small and large column leaching and finally trial heaps. Trial heap tests are very expensive and an alternative approach to this is large diameter column leaching.A four-column permanent facility was built at Teller to specifically evaluate the leaching characteristics of new dump leach ores. Details of construction, operation and dismantling are discussed in the paper. Capital cost for the four column facility was some $45 940, while operating costs are about $24 800 per column.

Jan 1, 1992

The need for a carefully prepared set of special conditions, to be used with general conditions of contract or, alternatively, a purpose written contract for adoption in tunnelling work in Australia is discussed. Recent decisions on the proprietor's liability for tender information and arbitrator's power to award interest are examined. A new clause for inclusion in contracts specifically giving arbitrators power to award interest is suggested. Similarly, a new clause covering delays due to environmental disputes is suggested, particularly for marine outfall tunnels. An alternative method for the settlement of disputes by negotiation is suggested for consideration and contracts and contract administration are discussed as the possible weak point in the construction process. At the conference it is intended to present a method or process to be used in contract administration which should reduce disputes, result in a better quality and efficiency of administration and ultimately in better contracts'.

Jan 1, 1981

Kalgoorlie Consolidated Gold Mines Pty Ltd (KCGM) is a management company, formed in 1989, to manage the assets and operate the Kalgoorlie joint venture for the owner companies Gold Mines of Kalgoorlie Limited (GMK) and Homestake Gold of Australia Limited (HGAL). Mining is still in progress on the 'Golden Mile' and surrounding areas more than 100 years after Paddy Hannan's discovery adjacent to the active Mt Charlotte mine. From 1893 until 30 June 1995 the Kalgoorlie Goldfields has produced approximately 45 million ounces (-1400 tonnes) of gold from mining and treating about 179 million tonnes of ore. This production equates to about 20 per cent of the total Australian gold production and about one per cent of the world's

Jan 1, 1996

The electrochemical dissolution of gold and other noble metals in hydrochloric acid using alternating current has been investigated. The experimental results show that this technique is efficient for dissolving pure noble metals and offers prospects for their extraction from wastes and poor ores.

Jan 1, 1992

For several decades miners have been obliged to maintain a vast supply of sharp steels at the working face to meet the hungry needs of rock-drills. In medium and large size mines this has meant the setting up of an organisation to store steels, to make and sharpen bits with all the complication and skill of forging, hot milling and heat treatment, and to transport sharp and dulled steels to and from the working face with all its labour, wastage, and inconvenience to other mining operations.In a mine with 250 rock-drills in use, a flow of more than 60,000 sharpened steels each month has to be maintained to keep the machines fully employed, so some idea of the magnitude of this problem may be grasped.For a long time it has been apparent that it is mainly the bit itself that wears, and many attempts have been made to reduce the enormity of the problem by providing detachable steel bits which could either be used once and rejected, or sharpened three or four times before rejection.At the same time metallurgists have striven to 'improve the quality of the steel and the heat treatment afforded it so that a bit, readily workable In a normal mine drill-shop, could be produced having a high resistance to wear and fatigue; but, although various alloy steels have been marketed, it is still usual to find many mines relying on a "straight" carbon (0.6 - 0.9% C.) steel for their drill steels.Since 1915 increasing use has been made of tungstencarbide as a cutting implement in the engineering industry. Where, on account of its great hardness and long life, it...

Jan 1, 1948

To secure a sustainable competitive advantage some smelters may need strategies based on flexibility in feed and product ranges depending on immediate future projections of profitability. This paper explores the technical requirements for strategic diversity in smelting, leaving procurement, marketing and contractual considerations aside. The days when a smelting operation is tied specifically to say only processing zinc concentrates are perhaps drawing to a close. While internationally traded mineral concentrates are available, attractive business opportunities must exist for fully diversified custom smelters. Certain new and emerging technologies have inherent characteristics that are evaluated in this context. The paper identifies the basic building blocks that will permit such a scenario and assesses the technical feasibility. The ability to respond flexibly to environmental pressures is highlighted as being of paramount importance.

Jan 1, 1996

By Matthew I. G, Hall P. G

The Selective Precipitation (Basics) Process is a means of controlling impurities such as the ions of Mn, Mg, and Cl as well as sulphate and water, in an electrolytic zinc plant circuit. This is achieved by precipita- ting zinc selectively as a basic zinc sulphate from a portion of impure circuit solution. The impurities remain in the solution, which can be discarded, while the zinc, substantially free of impurities, is returned to the main circuit by using the precipitate as a neutral- ising reagent. A description of the process and its development to a full scale operating plant at the Risdon Works of the Electrolytic Zinc Company of Australasia Limited is Presented.

Jan 1, 1977

By Harrison J

The correct selection of equipment to use in a mine is a problem which constantly faces the mining engineer. In some cases a wide choice of equipment with different operating characteristics is available. If this equipment is to be used to assist in moving the ore it may be possible to build a computer simulation model to predict how it will perform. Typical problems that lend themselves to this type of analysis are presented. The computer models are constructed using a recent form of the GPSS computer language, namely GPSS/PC for the personal computer. This language allows the programmer to construct models in a very short time and at a low cost. Of great importance is the easy way in which it is possible to change the models to answer any of the "what if?" questions the engineer may pose.

Jan 1, 1987

By Leigh J. H

A history is given of the dust control techniques developed and applied by the mining companies at Broken Hill. A history of the regeneration works undertaken since 1936 is out- lined. Particular emphasis is placed on the stabilization of mine residue dumps which are located throughout a belt of mining leases in the middle of the city and which began in 1937. The establishment of vegetation for dust control techniques is discussed in detail and a case study is given of the successful revegetation of the sides of a 650 metre long, 350 metre wide and 35 metre high residue dump.

Jan 1, 1976

By Lane G

This paper addresses project commissioning, that is, activities that culminate in the transfer of a project from the construction phase to routine plant operation. These activities should be initiated early in the engineering and design phase to ensure that the plant design is operator friendly and that construction is scheduled such that pre-operational testing and hand over to the owner occurs in a timely and cost-effective manner. For the purposes of this paper, commissioning includes all activities related to pre-operational testing, no-load testing, water commissioning, and ore commissioning. That is, all activities from construction completion to practical completion of the prime contract. This process is facilitated in numerous ways dependent on the nature of the project prime contract and the size of the project. For small lump sum projects, the contractor's responsibility may include all phases of commissioning to practical completion, whereas, a managing contractor on a complex multi-contract project may only be required to bring the project to mechanical completion and hand over to the owner for ore commissioning. Irrespective of the responsibilities, commissioning programs require careful planning, effective communication and detailed reporting. Unsuccessful

Jan 1, 1997

By Kolarczyk M

When controlling the ventilation process in a deep mine some knowledge of the sensitivity of the air volume output to changes in the resistances of network side branches is of great advantage.Sensitivity is taken to mean the limit of the differential quotient AV /ART where AV. is the change in air output in the i--h side branch caused by a change of resistance LI R in the r-th side branch. A method Is presen- ted for determining any arbitrary co- lumn of the sensitivity matrix. A network interpretation of this met- hod was developed in which an ancilla- ry network additional the basic network is constructed and solved, giving an analysis of the sensitivity signs de- pending on the structure of the network.

Jan 1, 1988

By Purvis A. H, Greenwood-Smith R, Sowerby B. D

A nuclear technique for the determination of copper and nickel in bulk samples and drill core has been developed at Lucas Heights andfield-tested at Mount Isa. The technique, which is highly specific to the element being measured, utilises the gamma-ray resonance scallering process.A bulk mineral analyser was installed in mid-1976 for the routine assay of copper in bulk samples and drill cores, and remained in operation until late 1981. The operation of the analyser over this five-year period is reviewed with particular emphasis on reliability, accuracy and principal usage.The main application of this analyser was in stope planning and design whereby several thousand drill-core and Wall-chip samples were analysed. It was also used as an aid to underground grade control of stopes where ore dilution by supporting barren backfill was a problem.

Jan 1, 1984

IN the course of his employment the Broken Hill Co. the writer has had occasion to use and instruct others in the use of the Shamrock rescue apparatus. This paper deals with the various types of apparatus tested. The common object of the various types of breathing apparatus is to enable the wearer to remain and work for varying periods of time in an atmosphere which is either deficient in oxygen or is poisonous that is, contains carbon monoxide or irritating and irrespirable vapours, such as the smoke from underground fires, sulphur dioxide or ammonia fumes. For any apparatus to be efficient as required in the above paragraph it must fulfil the following conditions;1. Air-tight as regards the passage of the air from the outside to the inside. In atmosphere containing carbon dioxide a slight leak would not render the apparatus useless; but where irritating vapours, such as the smoke from burning oregon and sulphides, are met with, even the slightest leak must be avoided.2. The oxygen supply must be ample, and so supplied that it is not checked by expiration.3. Expiration and inspiration must not be retarded.

Jan 1, 1911

By Weir D. R, Doyle B. N

The Sherritt Zinc Pressure Leaching Process is based upon the direct pressure leaching of zinc sulphide or lead-zinc bulk sulphide concentrates to produce zinc sulphate in solution and elemental sulphur in the leach residues. The zinc sulphate solution is compatible with conventional purification and electrowinning technology. The pressure leach residues can be treated for the recovery of elemental sulphur, lead and silver. With the conversion of sulphur to the elemental form, zinc pressure leaching allows zinc winning to be independent of sulphuric acid production. Direct pressure leaching of zinc sulphide concentrates was started commercially in October 1980. Continuing research and development studies have defined various pressure leaching configurations for integration with existing roast-leach operations, for grass roots plants, or for plants which are to have the roast-leach section completely replaced. These studies have included the treatment of zinc concentrates from various Australian producers and the development of process flowsheets for potential applications in Australia.

Jan 1, 1989

By Sullivan BJK

The 1100 orebody is a massive copper sul- phide orebody which contains a major portion of the Isa Mine copper ore reserves of 130 million tonnes at 3.2%. The underground mining of a deposit as large as the 1100 orebody is technologically a complex operation as extraction strategies have to be evaluated with reference to 1. rock mechanics considerations, 2. safety and environmental standards, 3. production and operating require- ments and 4. metal recovery and costs. The mining philosophy in the orebody has undergone considerable change over the past five years as a result of experience and improved technology. At this stage, primary stopes are extracted by high rise sublevel open stoping and pillars by slot and mass blast drawn either under rock fill or as an open Stope.

Jan 1, 1978