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In 1985 a 2.5-tonne top blown rotary converter was installed in the silver refinery at Cominco's Trail Operation to carry out the final cupellation of burndown metal to Dore metal. The furnace is fired with an oxygen-natural gas lance which is capable of achieving a variety of furnace conditions, varying from reducing to highly oxidizing. Reaction rates are about 4 times greater than using conventional cupel furnaces. The faster reaction rates improve productivity and reduce in-process precious metal tie-up. The furnace is also used to reduce litharge slag for bismuth recovery.

Jan 1, 1989

By Denholm WT

A mathematical model has been developed for intense pneumatic smelting processes, such as the Sirosmelt group of processes, to assist in establishing optimum process conditions and to permit operator training. The model first solicits input operating conditions from disk files and from the operator. During operation, the feed, fuel, and air (or oxygen) rates are automatically adjusted to maintain the desired process targets. Alternatively, these parameters, as with all other inputs, may be manually controlled by the operator. Selected process parameters are displayed to the terminal in a regularly updated diagram of the process,. Outputs of detailed information including heat and mass balances are available for immediate inspection or for use by ancillary plotting packages. Development of a robust free energy minimization routine has led to a flexible and time efficent model capable of handling a range of pyrometallurical systems. Modelling of tin smelting, lead smelting, copper smelting, matte fuming, and pneumatic steel-making has been sucessfully carried out. Typical outputs from the model are given and discussed in terms of their internal consistency and relationship to the operation of the relevant Sirosmelt process. `

Jan 1, 1984

Open stoping dimensions are typically controlled by a number of factors including production drilling capacity, scheduling, fill constraints, orebody dimensions and host wall rock conditions. Frequently host wall rock conditions are the key control on stope dimensions. As a new mine is brought into production, there is a steep geotechnical learning curve for those associated with the development of the mine. Initially, the experience and observations gained at other mines is used to guide the stope design. As experience is gained at the new operation, site specific techniques can be validated for use. This has been the case at BHP Cannington, where a heavy emphasis has been placed on the validation of empirical stope stability techniques for site specific conditions and experience. A range of empirical and numerical techniques can be applied during the design of open stopes. The empirical techniques are an experience based application of known performance levels during the design of open stopes. The numerical modelling and structural tools can be used to compliment the empirical techniques so that an understanding can be gained of the likely stress and structurally controlled failure mechanisms.

Jan 1, 2000

The use of black and white and colour infrared film in remote sensing of natural resources, is reviewed. In heavily-forested areas such as New Zealand, the main value of the method is in surveying the vegetation cover to detect the existence of plant communities characteristic of specific geological formations, By contrast, in and areas of Australia where the vegetation cover is sparse and where rocks and soils are well exposed, the method can be used in detecting different rock types or other geological differences.

Jan 1, 1971

The treatment meIhods selected for the concentrator at Cobar Mines Pty. Ltd. called for a high degree of automatic control of both the grinding and flotation sections.The resulting concentrator layout includes a central control room overlooking both grinding and flotation sections. The control room houses process recorders, controllers, and indicators. together with motor stopstart stations and alarms.Plant instrumentation includes load cells and variable speed hydraulic drive feeders for feed-rate control of autogenous mills, together with nuclear density gauges, differential flow transmitters, and pneumatic control valves for water and pulp density control.Flotation cell pulp levels are controlled by floats and pneumatic actuators; flotation reagent controls include magnetic flowmeters and time-operated solenoid valves.

Jan 1, 1969

A zone rich in-fish debris in the Rolling Dow= Group in the sub-surface of the Great-Artesian Basin has been discovered a Further research has shoe i this zone to-be of very wide distribution in the Artesian Basin and to occur. at the base of the Ta?nbo .f ormati'on resting on the Roma forma-tion. The zone gives a very characteristic curve on the electric and' gamma ray logs and is thus an excellent correlation marker in the sub-surface over a very wide area. It is probably to be correlated sith.the Toolebuc member described from: outcrops east of Boulia. There .are apparent similarities between the Fishecale zone of the Great Artesian Basin in' Australia and the Fishscale sand of the Western Canada Sedimentary Basin.

Jan 1, 1962

By Brant BA, Lewandowski R, Trendle M, Haughton D

There is a vast amount of geotechnical data, which can be obtained during exploration programs at new and existing mine sites. Additional information on the performance of the in-situ rock mass can be obtained from bore cores, which are usually only geologically logged and then stored. A computer based data management system for storage and retrieval of geotechnical data has been developed to access and manipulate such data.

Jan 1, 1983

Paste Thickening of Tailings at the Clermont Coal Preparation Plant

Sep 13, 2010

Porgera is located in the Central Highlands of Papua New Guinea. Porgera Joint Venture treats a high grade epithennal gold deposit. Most of the gold occurs as submicroscopic particles in a sulphide matrix although there is some quite coarse free gold. Anticipated gold production is 900 000 oz per year for the first six years of operation.Stage I of the treatment plant consisted of a concentrator and leach/CIP Circuit. It was commissioned in August 1990. Design throughput was 1500 tpd with an anticipated gold recovery of 60 per cent. Throughput achieved was actually 1850 tpd with an average gold recovery of 69 per cent. CIP tails were accumulated in a pond awaiting retreatment by pressure oxidation.

Jan 1, 1992

By Harraway DH, Tanner AC

The various circuits tried!at Mount.Isa Mines during the period 1959-1963 to improve the differential%f lotation of galena and sphalerite are reported. The benefits and disadvantages of 'the various circuits are discussed. An analysis of ore charao-beris;ics.and their effect on flotation is followed by the d~soription,of a proposed".cirouit in the process of install-ation.

Jan 1, 1963

By J K. de Wet, G Balassone, J D. Singleton, V Arseneau

The Accha-Yanque zinc belt in southernPeru is a major zinc-lead rich metallogenic province. In the belt are comprised several non-sulfide-type occurrences, extending on the periphery of the Yauri-Apurfmac batholith (Oligocene-Miocene). Zinc mineralisation at Accha (almost fully oxidised) occurs in breccias of sedimentary and tectonic origin in the limestone of the Ferrobamba Fm (Middle to Upper Cretaceous). Non-sulfide association consists mainly of smithsonite and hemimorphite replacing both primary ore minerals and carbonate host rocks. Mn(hydr)oxides and Zn-clays (sauconite), can be locally very abundant. Differences in mineralogy of the ore and gangue minerals, as well as the composition of the host rock can have a profound impact on zinc recovery and reagent consumption, and therefore on the economic value of the deposit. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Masters I. M, Ozberk E, Chalkley M. E

The integration of iron rejection as hematite with the Sherritt two-stage zinc pressure leach process has been investigated on the laboratory scale. The two-stage pressure leach process is applicable for a greenfield zinc plant, or for replacement of the conventional roast-leach circuit in an existing zinc plant. An excess of zinc concentrate is used to accomplish acid neutralisation in the first stage of pressure leaching, and the residual concentrate in the first stage residue is treated with an excess of acid solution in the second stage of pressure leaching to yield high zinc extraction. Integration of hematite precipitation with this process allows for the potential sale of the iron residue, greatly decreasing the residue disposal problem. Two flowsheets containing the desirable features of both of these processes are described in this paper, along with laboratory Results.

Jan 1, 1993

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

By S Strohmayr, R Harvey, A See

Ernest Henry Mining Pty Ltd started production in August 1997. The Ernest Henry orebody consists of two distinct parts, a complex supergene ore zone overlying a primary ore zone. The economic copper minerals in the supergene ore were chalcocite, bornite, secondary chalcopyrite and native copper while the primary zone has only chalcopyrite. The variability of the supergene zone made concentrator operation difficult and predicting metallurgical performance using mineralogy essential to establish the capabilities of the concentrator. A paper presented at the 1998 Mine to Mill Conference entitled Mineralogy Controlling Metallurgy at Ernest Henry Mining (Barnes, Strohmayr, Brindley and Munro, 1998) presented the testwork and initial plant surveys that showed that the mineralogy of the ore controls the metallurgy of the concentrator. This paper presents the data obtained from the subsequent years of operation treating both the supergene and primary ore types. A review of the actual supergene mineral distribution in feed and subsequent recoveries compared to those predicted as part of the flowsheet design is also presented.

Jan 1, 2003

Studies of the morphology of seamounts within the Hawaiian, Line Islands, Gilbert and Phoenix Seamount groups indicate that the morphology and size distribution of seamounts vary significantly from one seamount group to another. The Line Islands group appears to be the most complicated of all the groups studied thus far. This group is complicated by reactivation of volcanism, which has superimposed volcanics on sedimentary rocks. These seamounts display abundant volcanic features on their summits. Seamounts within the Hawaiian seamount chain display a marked absence of volcanic features due to the . presence of thick carbonate caps. Reef platforms and sealevel benches are very common on these seamounts but are absent from seamounts in most other seamount chains in the central Pacific. Slope angles vary regionally between seamount groups. The minimum slopes are found on Necker Ridge in the central Pacific basin. The maximum slopes are found on ridge-crest seamounts. Roughness increases proportionally with mean slope angle.

Jan 1, 1987

By Goldie R

The use of options theory in business has become well established in recent years and is currently one of the most exciting areas of current finance research. The theory can be used to value levered firms, and streams of contingent payments. This technique also has very practical applications in the areas of capital investment analysis and the valuation of equities in the natural resource industry. The use of options theory has been well accepted and used for many years in the trading of commodity options and futures contracts, in banking and insurance and in other industries. It also can be used to value such diverse contingent claims problems as the income tax liabilities of the firm and share underwriting agreements.Its application to the more complex options, such as those present in the resource industry, is only now becoming known. This lag is, at least partially, due to the difficult mathematics involved in solving complex options problems. Another factor is the almost overwhelming abundance of uncertainties, such as grade, tons and other natural risks, which must be considered in the evaluation mining projects.

Jan 1, 1990

By Thomas E. G

In the economic evaluation of any Australian mining project, changes in taxation can significantly affect viability. Australian tax laws, particularly in the period since early 1973, have undergone many changes which have led to shifts in the profitability of mining companies. This paper examines the sensitivity of a selected, broadly based sample of Australian mining companies to the changes that have occurred, or are reasonably likely to occur, in taxation legislation. In the past, tax systems have been altered for a variety of reasons, such as 1. reduction'in the impact of inflation 2. neutralization of incidence between different sections of the economy 3. as an incentive to encourage expansion and growth in a particular industry or area, and 4. increase in the real "take" of government. In this paper, conventional rate of return analyses are applied in a study of how profitability is affected under various taxation systems.

Jan 1, 1977

By M S. Gallagher

In todayÆs high tech world, systems are getting bigger, faster, better. To remain at the leading edge, in any business, depends on accuratebut flexible design thereby allowing operational managers to providealternatives to improve their operations. The ultimate goal is to deliver to plan, with optimum economics. Mining is no different; with falling prices and escalating costs,improved margins become the focal objective. There are many ways toachieve this, ranging from operational efficiency improvements through production scenarios to planning initiatives. Of all, planning usually receives the least attention, yet it is the area of most influence on the Net Present Value (NPV) of the reserve. With computer technology, numerous concepts and iterations are possible thereby closing the gap between optimal and actual design. This paper discusses the application of the split shell design at the De Beers Venetia open pit in South Africa.

Jan 1, 2001

By Morley I. W

Offshore minerals legislation has been introduced to provide jurisdiction over the exploration and recovery of mineral resources, particularly petroleum, from the territorial waters and parts of the continental shelves adjacent to coastal states. Ratificat- ion of the 1958 Geneva Conventions on the Law of the Sea has provided some measure of international agreement amongst signatory powers. Because the relationship of the Australian States to the Commonwealth in their federal system, the Australian offshore petroleum legislation is of particular interest. The customary role of the States in mineral resources management, which has extended to the offshore, is under challenge from recent unilateral Commonwealth Government legislative actions in the fields of mineral resources jurisdiction. Environmental considerations provide an additional issue, as yet unresolved, with the delay in submission of the Report of the Great Barrier Reef Petroleum Drilling Royal Commissions

Jan 1, 1974

The development of the lower Hunter Valley, centred around Newcastle and its suburbs is closely linked to the mining of coal and the settlements which grew to house the colliery officials, the miners and their families. The Port of Newcastle expanded and developed as a port exporting coal to many ports of the world ranging from Hawaii and Brazil to Japan and Korea. The coal which passed through the Port of Newcastle, depend- ing on the historical period in question may have been mined in Newcastle itself, or one of the nearby colliery townships such as Lambton, Wallsend, Charlestown or Hamilton, or from one of the estuarine collieries located at Carrington or Stockton or from the West Wallsend area or from East Greta, Pelaw Main or Cess- nock located on the South Maitland (Greta) coal field or from the open cut and underground mines of the Singleton Coal District.

Jan 1, 1988