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The Warner Process has been devised to produce zinc metal directly from sulphide, thereby reducing the requirements for purchase of large amounts of energy in a special form. The process conditions for a practical process have been evaluated in an extensive program of research and development at the University of Birmingham. Recorded data now exists to take the process forward to commercial use within the next five years. The industrial economics have been evaluated. The cost of making zinc metal from zinc sulphide ore can be substantially lowered due to the reduced energy cost, locating zinc production in the neighbourhood of the mines and increasing ore to metal recoveries - particularly for fine-grained and pyritic ore. Integration of a Warner Furnace with a zinc mine and concentrator can result in a highly attractive return on capital Invested.

Jan 1, 1993

By Lynch AJ

Comminution within rod mills has been investigated by izse of a matrix analysis of breakage processes. A para,~ meter, the number of breakage stages, has been introduced and cornfninut-ion within all rod mills has been expressed in terms of the¦1-number of breakage stages- and a function which des--cribes' the feed rate, mill diameter and mill speed.'The effect of variation in feed rate, feed sizing analysis and mill speed on the number of breakage stages-is-,-discussed.

Jan 1, 1963

By Tonkin D. A

Poor performance in the several stages of the magnetite recovery circuit, coupled with poor desliming through inefficient and over- loaded desliming screens, led to excessive magnetite consumption. An accurate and reliable sampling programme was established covering all outlets of the plant. Emphasis was placed on frequency of increments in an endeavour to detect extreme conditions of short duration. Systematic checking of the entry points to these outlets than identified those sections of the recovery circuit at fault, namely magnetite recovery separators and the heavy media cyclone product rinsing screens. More product rinsing water was provided, and modifications to the rinsing screens improved the efficiency of these units. Consistency of operation through automatic control of level eliminated the sudden massive losses in the magnetic separators. Load on the recovery circuit was then reduced by improvements to the raw coal desliming screens. A 50 per cent reduction in magnetite consumption was achieved.

Jan 1, 1974

Although the last decade has seen the growth of many new licencing and approval requirements for the exploration and mining industries, there remains in each State of Australia and the Northern Territory a predominant "Mining Act" containing provisions for the grant of exploration and mining tenements. What then are the rights and duties of tenement holders either by virtue of a Mining Act or through other approval and licencing mechanisms? What rights and duties does a person acquire when he is granted an exploration licence or a mining lease? In this paper I will attempt to cover these types of questions using in particular examples from New South Wales. I will also refer to a range of other subordinate approvals and licences which today's society requires and the need for ethics and recognition of liabilities.

Jan 1, 1995

IntroductionOre BodiesRio GrandeBlack RockLeadCopperBlack StarLeadCopperStoping Methods and DesignFactors Affecting Ventilation PracticeTemperatures and Climatic ConditionsGeothermic GntdlentLegal RequirementsMine CasesMain Ventilation SystemMajor Fans and ShaftsVentilation CircuitsMan and Supply Shaft; No. 2 Ore Shaft; Urquhart ShaftMan and Supply Shaft; Davidson Shaft; No. 46ShaftLawlor Shaft; Urquhart ShaftControl of VentilationSummary of Upcasts and DowncastsAuxiliary VentilationType of Fans used, Vent Pipe, etcVentilation and Temperature SurveysDust SurveysInstruments Used

Jan 1, 1953

The interaction of flotation collectors with sulphide minerals takes place at the solid - solution interface. The electrochemistry of the processes which affect this interface are discussed. The interaction of xanthates with sulphides is an electrochemical process, xanthates being electro-oxidized to chemisorbed xanthate and dixanthogen. The role of oxygen is to provide a cathodic process to allow the anodic oxidation to occur. The hydrophobic condition of the mineral surface is brought about by the presence of the oxidized xanthate species. The action of reagents which can activate or depress the flotation of sulphides is discussed briefly.

Jan 1, 1980

By R H. Boffey

The Osborne copper-gold deposit was discovered in North-West Queensland in 1989. Underground production activities commenced at Osborne deposit in April 1996. This paper will examine technical and operational aspects of the underground mine during its development to a 1.2 Mtpa operation . Technical aspects discussed include geology, mine design and mining methods, equipment fleet selection and capital infrastructure. Operational aspects discussed include the evolution and performance of the integrated work teams that are utilised at Osborne to perform all mining and maintenance activities.

Jan 1, 1998

Record quantities of slag were produced in 1974. Slag usage in this year amounted to 8.5 mega tonnes for granulated blast furnace slag and 7.7 mega tonnes for crushed blast furnace and L.D. slags. Granulated blast furnace slag is mainly used as a hydraulic bonding material in the manufacture of cement and in road construction. These applications give a fuel saving and reduce processing costs. Crushed blast furnace and L.D. slags find application as a substitute for natural aggregates in road construction and in the production of concrete. There is no doubt of ttie interest to utilise to the maximum all the slag produced by the steelmaking industry, thus preventing the build up of slag heaps detrimental to the environment and favouring the disposal of the heaps formed in the past. World wide efforts are being made to achieve this objective.

Jan 1, 1979

By D Jones

The development, piloting and engineering design of an innovative water treatment system for process water produced by a uranium mine mill are described. The process incorporates lime/carbonate softening (Stage 1), reverse osmosis (Stage 2) and biopolishing (Stage 3) to produce water of quality suitable for release to the receiving environment. Comprehensive performance data are presented for each stage. The unique features of the proposed process are: recycle of the lime/CO2 softening sludge to the uranium mill as a neutralant; potential use of power station off-gas for carbonation; and the potential recovery and recycle of ammonia from the RO reject stream.

Jan 1, 2003

This paper describes the planning mechanism and implementation of a progressive rehabilitation programme at Hunter Valley Mine in the Upper Hunter Valley of New South Wales. Hunter Valley Mine is a large open cut coal mine which produces approximately 7.0 million tonnes of coal (run of mine) annually for export. This production level involves the movement of some 60 million tonnes of waste and coal each year.The rehabilitation programme at Hunter Valley Mine has been developed to provide a combination of pasture, based on improved pasture species and timber belts to enhance the visual characteristics of the rehabilitated landform, whilst creating amenity in the form of shade for livestock.The operational philosophy for the rehabilitation programme is that of progressive rehabilitation. The best time to undertake rehabilitation is now.' As a result, planning for the rehabilitation programme is continuous, so that all site works are completed in time for vegetation establishment during the critical periods each year.

Jan 1, 1992

By D von Horn

Mineral sand orebodies are typically mined for their TiO2 content. Increasingly over the past 30 years, the major mineral focus has shifted from natural rutile to ilmenite and an acceptance that the latter generally needs some form of upgrading for economic conversion into TiO2 pigment. This upgrading obviously has a cost, and in conjunction with diminishing mineable feed grades, results in higher cost TiO2 units for chloride route Pigment Plant feedstocks. The net cost of feedstock can be significantly influenced by the recovery and sale of accessory minerals and by-products from the processing chain to the extent that some producers have the potential to achieve a zero net cost. Whilst slagging plants typically reduce net cost from rutile, zircon and pig iron revenues, operations supporting Becher type synthetic rutile operations have been limited to revenues from rutile and zircon only. A range of alumino silicate minerals show industrial potential, as does activated carbon, iron oxide and gypsum, by-products of the synthetic rutile process. Tiwest is a good example of a company maximising revenue from the accessory minerals as well as from by-products of the synthetic rutile process.

Jan 1, 2001

The Prospero orebody is a part of the Helene mine at Cosmos and was scheduled to begin production in March 2008 after the exhaustion of the Tapinos orebody in the same mine. Treatment of the Tapinos orebody was challenging and it was envisaged that Prospero would have similar properties given that it was also anomalous in deleterious elements and would be of a similar mineral hosting. It was deemed necessary to undertake a metallurgical test work program to identify any potential processing issues, complex mineralogy or significant metallurgical domains. The paper discusses the processes which were employed to undertake the metallurgical test work program and describes the aspects that can be employed by other developers to quickly and effectively assess potential future orebodies. It will demonstrate that the work was successful at determining expected metallurgical behaviour, providing direction for mining operations and highlighting areas for more extensive research.

Jan 1, 2009

By McKee DJ

Many workers have observed an inverse relationship between final concentrate grade and valuable component recovery achieved by a flotation circuit, i.e. an increase in either grade or recovery may only be achieved at the expense of the other. The relationship is termed a "grade-recovery" curve and, in theory, limits the separation obtained by the circuit. However, circuit surveys in a nickel concentrator indicate that the operating "grade-recovery" curve of a circuit is not only determined by the nature of the ore and the circuit operating conditions, but also by the circuit design, particularly in terms of stage capacities. The surveys show that different capacity circuits can produce different operating curves for the same ore, and that capacity reallocation between stages has the potential to improve both grade and recovery. In particular, the relationship between circuit design and operating curve position is shown to be a function of the circulating loads generated by the circuit design, balancing the beneficial effects of recycling material against the proportion of plant capacity consumed by recycling.

Jan 1, 1986

Reservoir Engineering has developed into an art. One phase of this art is forecasting the futi. perf ormance of oil and gas reservoirs for property valuations. A discussion of the necessity for oil property valuation isgiven. A brief 'discussion of the four most common methods is included and the engineering method is explained in more detail. As an example of oil property valuations, a producing oil lease in Shackelford County, Texas, USA is evaluated.' The recommendations and conclusions arrived at frun the results obtained are presented.

Jan 1, 1962

By Fewings JH

When the mining and milling of 1100 Copper Orebody commenced, difficulties were experienced in producing a satisfactory grade of copper concentrate. The major concentrate contaminants were fine pyrite and silica, particularly in the minus 10 microns fraction. Studies of the 1100 Orebody showed that much of the fine grained pyrite and a proportion of the silica present in the ore contained carbonaceous matter in the form of complete or partial rims and as internal carbon films disseminated throughout grains. The hydrophobic surface property of the carbonaceous material resulted in an inherently flotable fine pyrite and silica fraction. The addition of a 60:40 mixture of nigrosine and dextrine, initially to a prefloat concentrate of the inherently flotable carbonaceous material and finally to'the total copper flotation feed, successfully controlled the flotation rates of the carbonaceous pyrite and silica. The objective of a 25 per cent Cu concentrate grade was then achieved without decreasing copper recovery.

Jan 1, 1970

By Stewart Gillies AD

Resource rent taxes are taxes which only become effective at such a time as a pre-determined rate of return has been achieved by an operation. Resource Rent Taxes have from time to time been considered for implementation in both Australia and New Zealand. The offshore petroleum industry in Australia is already subject to RRT as is the Roxby Downs (Olympic Dam) Mine in South Australia. Both the mining and petroleum taxation regimes in Papua New Guinea include a resource rent tax component called Additional Profits Tax.

Jan 1, 1995

Natural gas is a comparatively new fuel in Australia. It was first used in small quantities in Queensland in 1965, but it was not until 1969 that natural gas reached the capital cities Brisbane, Melbourne, and Adelaide in that order; then in 1971 it reached Perth. By the mid seventies, natural gas had secured a significant proportion of the energy markets in Queensland, Victoria, South Australia and Western Australia and in 1976 supply commenced in Sydney. In that year - 1976 - gas supplied about 12.5% of the total demand for primary energy in Australia excluding transport. In the current financial year - 1981/82 - natural gas is expected to supply nearly 19% of the market and forecasts for 1990 range up to 25%. From a starting point in the late 1960's when manufactured gas supplied a small but important proportion of the non-transport energy market - less than 3% - we have exper- ienced an average growth of nearly 24% per annum up to the present time.

Jan 1, 1982

By T Galvin

Drilling and blasting at Westside Mine near Wallsend, NSW, has presented a challenge for Orica Explosives, Australia. The colliery produces 600 000 tonnes of steaming coal per year from two seams using surface mining techniques. Tapping into underlying coal will greatly improve the yield, but there are many issues which make this an enormous challenge. Hunter Valley Earthmoving engaged Orica Explosives to supply the explosives products and to provide much of the blasting expertise that is needed on the minesite. Hunter Valley Earthmoving and Orica Explosives have proven to be an outstanding, unified technical team on this project. The success of the team is based on good communication, progressive attitudes, extensive expertise in blast design and most importantly, care and accuracy in implementing the agreed upon designs.

Jan 1, 1999

By Denholm WT

The main objective of the experimental study was to investigate the dissolution kinetics of various forms of carbon under iron bath converting or smelting-reduction conditions, i.e., particulate, free moving carbon in contact with a turbulent iron melt. Iron/carbon melts were contained in cast magnesia-lined silicon carbide crucibles heated by a medium frequency induction furnace. The melts were stirred by injecting nitrogen through 2 mm I.D. alumina lances submerged to a depth of 50 mm in the 100 mm deep baths. Particulate carbon in the form of graphite, brown coal char and petroleum coke, were dropped directly onto the turbulent bath. The dissolution rates of the various carbon types were monitored by taking periodic bath samples for subsequent carbon analyses. The effect of carbon particle size (1-6.25 mm), the degree of bath turbulence (nitrogen stirring rates of 0-20 litres/min), and bath temperature (1300-1500¦C) were assessed. The analysis of the results was complicated by particle buoyancy effects, but it was established that the dissolution rates of the three carbon types investigated were similar, and increased linearly with increases in the gas stirring power inputs. Particle size had relatively little effect on the dissolution rates.

Jan 1, 1984

By P Hucker, E Hall

Harmony Gold operates the Mount Marion underground gold mine near Kalgoorlie, Western Australia. The mine consists of two ore zones, East and West, and mining of these zones is currently conducted using the sublevel caving method. When mining commenced in the Western zone, the span was insufficient to induce caving of the country rock above. Dyno Nobel, together with Harmony and 360 Drilling, developed an innovative drill and blast solution in order to promote cave propagation and improve the safety of personnel at the operation. The solution involved a series of shallow angle drill holes up to 90 m into the hanging wall of the West zone. These were charged with Titan« 7000 underground bulk emulsion and the HotShotÖ electronic initiation system. The blast used over seven tonnes of emulsion and 46 detonators and achieved the desired result without damaging nearby mine infrastructure.

Jan 1, 2007