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By J-P Franzidis

Hydrodynamic conditions such as gas dispersion, mixing intensity and solids suspension are known to govern the metallurgical performance of the flotation process. Understanding flotation cell hydrodynamics is therefore important for the optimisation of existing cells and for the design of the larger and more efficient cells which are needed to handle the finer, lower grade ores currently being mined. This paper presents the results of numerous studies that have been carried out to characterise the hydrodynamic conditions in a number of different types of flotation machines both in Australia and South Africa. Measurement techniques that have been developed to determine gas dispersion and other hydrodynamic properties in industrial flotation cells are described along with applications for their use. The results show distinct differences between the way flotation cells are operated in the two countries.

Jan 1, 2000

By M Roche, W J. Huxley

Finding a balance between practical and acceptable groundwater management, and providing for the needs and impacts of mining developments remains a challenge. The changes that accompanied the recent implementation of water reforms have provided greater flexibility for the water manager and greater certainty for the resource user. However uncertainty associated with understanding of complex aquifer systems, balanced against providing for the needs of mining developments, the rights of existing water resource users and expectations of the broader community have not diminished the conflicting issues faced by water resource managers and resource developers. Licensing under the Water Act 2000 provides the regulatory link with the taking of water for water supply purposes or as a consequence of the mining activity. This paper outlines key elements of sustainable water resource management involving certainty of access to water and adaptive environmental management that are delivered through conditioning the water licences issued for the particular mining development. Implementation of this approach is illustrated through a case study involving the BHP Billiton Cannington Mine in North West Queensland.

Jan 1, 2003

By Weller KR

Computer programs are described which help the metallurgist to process sample data from a plant survey; to carry out simple mass balance calculations; to present the results of circuit and equipment performance in convenient form; and to simulate the circuit response to changing operating conditions. The uses and limitations of these programs are explained by following through a case study of the sulphide flotation circuit at Cleveland Tin Ltd. The circuit was sampled, the data analysed, and some process inefficiencies established. Simulation calculations were then made to provide information on which to base decisions regarding possible circuit changes aimed at improving performance.

Jan 1, 1983

Immigration has influenced Australia's development more than any other factor. As well as being critical to our economic growth and development, it has made a major contrib- ution to our population growth, to the richness and diversity of our society and to our inter- national relations. Migration from the United Kingdom has been the mainstay of our settler intake for many years, but its relative importance has declined in recent decades. Non-British European migration formed an important part of our post-war intake and, in the past few years, migration from Asia has reached significant levels - particularly through our resettlement of Indo-Chinese refugees. In planning our future immigration, it is important to look beyond short term direct economic consequences. Australia has looked to its resources for progress, but Japan, Korea, Taiwan and Singapore have achieved dramatic economic progress without resources, based on the will and dynamism of their societies. Immigration can contribute greatly to the development of a dynamic, outward looking Australian society able to make the most of our great resource potential.

Jan 1, 1982

Although technology and circumstances are in a constant state of change, the principles of managing the human element remain constant. The isolated mining community continues to form the backbone of the minerals industry but the nature of the isolation, along with the economic and political environment of the industry, is changing. These changes require new inputs by management to the workforce. Management must determine an effective working relationship with unions on its mine site and concurrently contribute to the build- up of the expertise of the individual worker through training and communication. It must also retain a proper balance, by way of human contribution, in cost and information reporting and in other areas amenable to computerisation. These comprise the aids to management necessary to achieve the desired operating efficiency and profitability.

Jan 1, 1980

By Parker GJ

The financing of smaller resource projects has proven to be a difficult problem for promoters and financiers alike as very often such projects have not met the requirements of available financing methods and promoters have equally found it difficult to establish credibility, management and technical ability with potential financing sources. Solutions to the dilemma in which many of these projects find themselves are not readily apparent but will need to be found if the full potential of Australia's resources is to be realised. INTRODUCTION The growth of so called project financing in its present form is normally considered to be a phenomenon of very recent times, however, paradoxically there are references to what could be called financing in the old testament. To confuse the issue further financing small resource projects may not, and very often are not undertaken on a project financing basis. It is therefore quite apparent that one should be completely clear on:

Jan 1, 1982

The Proterozoic Pb-Zn deposits of the Gulf of Carpentaria, Australia, include HYC (McArthur River), Mt. Isa, Dugald River, Lady Loretta and Hilton. Two seamingly incom- patible depositional models have been proposed to account for their origin. Finlow-Bates (1980), Large (1983) and Russell(1983) classify these-deposits as sediment-hosted submarine exhalative deposits. This class includes Rammelsberg, Meggen, Silvermines, Sullivan and others. In contrast, a lacus- trine, shallow-water origin has been advocated by Williams and Logan (1981), Logan and Williams (1984), Muir (1983) and Eugster (1985). The discrepancies between these two models can be removed by creating a separate class, that of continental sediment-hosted exhalative deposits.. HYC., Mt. Isa and Dugald belong to this class and their sediments were deposited in shallow, alkaline lakes. Metal- rich, hot, Na-Ca-Cl brines entered the basins along boundary faults and interacted with pore fluids and sediments, depositing-Cu-Zn-Pb sul- fides. Similar brines entered the Lady Loretta basin after marine flooding, depositing sulfi- des and barite, placing Lady Loretta into the class of marine Sedex deposits.

Jan 1, 1987

By D R. Swinbourne

In the recent past a number of smelting plants were commissioned in India to supply the rising demand by domestic steelworks for manganese-based ferroalloys, and they enjoyed cheap electric power and readily available high-grade manganese ore. Presently, the cost of electric power is much higher than in some neighbouring countries, there continues to be poor transport infrastructure and the prices of high-grade manganese ore have increased. Additionally, the Indian Government has opened its economy to the outside world, resulting in the import duties on ferroalloys being drastically reduced. In this paper the current situation in India will be detailed, the electric arc furnace and blast furnace smelting methods for ferroalloys compared and proposals for the construction of a new ferromanganese blast furnace in India outlined. The future of ferroalloy smelters in India will be assessed and actions which could be taken to improve their position discussed.

Jan 1, 2000

By Onal G, Celik MS, Dogan MZ

Chromite tailings assaying 21.2 per cent Cr2O3 was upgraded to 48.7 per cent Cr2O3 at a recovery of 72.0 per cent using column flotation with a mixture of anionic collectors at pH 11. Electrokinetic methods were used to elucidate the mechanism of collector adsorption and correlate the findings with the optimum flotation conditions. Multivalent constituent ions such as Cr3+, A13+, Fe2+ and Mg2+ were found to adsorb on chromite surface and shift the zpc of chromite in the direction of oxide form of the mineral. The anionic collectors also imparted a negative charge to chromite in the entire pH region. The higher zeta potentials obtained upon adding the anionic collectors is ascribed to the adsorption of anionic surfactant onto the positively charged chromite surface. The positive sites are generated through formation of significant amount of hydroxy complexes of magnesium at pH 11. Complementary infrared data reveal the absence of a shift in the spectra indicating the possibility of physical adsorption in the system.

Jan 1, 1993

By P Sutton

The global goal of Sustainable Development is not achievable without major changes in the way goods and services are delivered and material needs are satisfied, which requires tremendous innovation in the supply chains and life cycles in which minerals and energy processing take part. Values derived from minerals and metals processing need to be delivered with a fraction of current ecological impacts, which means removing technical obstacles to eliminating waste and emissions in the minerals cycle. The challenge is to find economically attractive ways to get there, through eco-efficiency gains in existing operations, capturing regional synergies, streamlining and greening the materials supply chain, and commercialising new process technology and new products. This paper summarises the outcomes of the Sustainable Resource Processing project, which was designed to provide a strategic analysis of what sustainability means for minerals and metals processing and how that can be effectively translated into technical and business innovation.

Jan 1, 2002

"DEEPHOLE " or "Longhole" drilling is the name given to the drilling of prospecting holes with the pneumatic hammer drill. The drilling bit is of the same form, and is prepared in the same way as ordinary rock drill steel, and is extended to the bottom of the hole by sectional hollow rods, through which water is forced.The cuttings from the hole provide a sample of the ground drilled.Deephole drilling was developed at an American mine where the cost of diamond drilling, owing to loss of diamonds, was excessive, and proved very successful, holes being drilled as deep as 220 ft., in limestone, at a cost of one dollar per foot. The use of the method in other mines, and in a variety of rocks, has since been described in the technical literature. From the published descriptions the following data are drawn:

Jan 1, 1930

By Adam R. A

Techniques for the optimisation of open pit design and development are now accepted as standard practice in the mining industry. These techniques are used to analyse the impacts on project profitability of factors such as product price, slope design criteria and equipment selection. A fundamental assumption used in this type of analysis is that dump and stockpile designs and sequencing are predetermined. The cost of haulage for a typical truck shovel mining operation is in the range of 25 - 50 per cent of mine operating costs. Substantial cost savings can be achieved by optimisation of dump design and location of associated road and ramp systems.Factors which affect both the operation and total cost of dumping include; Ramp gradients and location, road design, dump placement and shape, dumping height, slope design (interim and final), slope stability, environmental requirements and equipment selection. This paper discusses these factors and their effects on the total mining operation and project value. Reference is made to case studies in which some of these factors have had a significant impact.

Jan 1, 1992

By I Lipton

Dilution and ore loss have an important bearing on the success of open pit mining projects. Their impacts on production costs, revenues and production rate require that they are correctly modelled in the long-term mine plan. The estimation of dilution and ore loss is therefore an essential part of any Ore Reserve estimate or mine schedule. Large open pit mines are driven by the economies of scale that are achieved at the cost of less selectivity in the discrimination of ore and waste. Planning for these mines is facilitated by the use of block models for mine design, scheduling and the conversion of Mineral Resources into Ore Reserves. This paper reviews various approaches to the estimation of dilution and ore loss, as implemented in computer block models. In the case of orebodies with well-defined sharp boundaries, rather than irregular stockwork mineralisation, the geological interpretation is a critical factor. Variability in the geometry of orebodies is common within large open pits and must be taken into account when estimating dilution and ore loss. A method of regularisation, controlled by the wireframed geological model, is demonstrated, using examples from large open pit stratiform copper and magnetite deposits. This can be carried out without special computer software modules.

Jan 1, 2007

Access to land for exploration, development and mining purposes is extremely critical to the viability of the mining industry and subsequently the well being of society.The mining industry has been subject to environmental controls and considerations for the past 20 years. Today there is greater land use competition and more debate as to its use. To retain reasonable access the mining industry must comply with the rules and regulations by which it is governed.A new set of rules and regulations have been approved for use in Queensland, known as the Mineral Resources Act 1989. This Act clearly outlines the titles available and the requirements to obtain access.There are three main titles of interest to mining companies. These are an Exploration Permit, Mineral Development Licence and a Mining Lease.The Exploration Permit (EP) is for exploration purposes. Applications for EP's are assessed on their content and past performances. An EP is granted subject to a security deposit and conditions. Prior to entry the EP holder is required to inform the land owner of the proposed activities and times of entry.

Jan 1, 1990

By M Harris, C Goodall, B Knopjes

The objective of this work was to investigate the effect of milling and flotation circuit configuration on flotation performance of platinum-bearing ore from the UG2 reef of the Bushveld Igneous Complex in South Africa. Pilot plant trials were conducted at Lonmin Platinum using a highly automated pilot plant (a floatability characterisation test rig or FCTR), with a pilot ball mill, a stirred media detritor and an ISA mill. Different milling and flotation configurations were tested, without changing the overall grind size distribution or flotation residence time from one circuit to the next. Results from the pilot plant tests indicate that staged grinding, with intermediate flotation stages, can achieve significant performance benefits in comparison to a single grind-float circuit, for an equivalent overall grind and flotation residence time. These findings are explored qualitatively, in terms of the recovery and transportation of fast, slow and non-floating platinum-bearing particles through the various milling and flotation stages, and an optimum strategy for the separation of this type of ore is explored and discussed.

Jan 1, 2005

By Walker V

The 'MAGNADET' to provide a safe enhanced protection extraneous currents, electricity and radiodetonator was designed electric detonator with against the effects of current leakage, static frequency energy.It has found a particular niche in shaft sinking operations and Mount Isa Mines initiated trials of the system in 1983 as part of the design work for the 3000/3500 orebody access shaft.Initial surface blasts indicated a number of significant advantages which were confirmed during the bench and concrete phase of the M37 shaft sink. The application of 'MAGNADETS' was later extended to the horadiam phase of the project.Details of the exploder capacity calculations for the various M37 round designs are included with the paper.

Jan 1, 1985

Traditional methods for monitoring, and hence controlling, pyrometallurgical processes rely heavily upon the skill and experience of operators. A skilled operator will usually achieve consistent, though often conservative, results, whilst an un-skilled operator will require considerable time and training to achieve the same results. Semtech Metallurgy AB have demonstrated that continuous and precise control of pyrometallurgical processes can be achieved through on-line analysis of pyrometallurgical flame off-gas using optical spectroscopy. The feasibility of the technology has been demonstrated on a large number of full-scale tests at production plants and by several commercial installations. Evidence suggests that installation of this technology, called Semtech Optical Production Control (OPC), has resulted in considerable economic benefits to the plant efficiency and asset life. These economic benefits are believed to be a direct result of improved objective on-line control. Technically the following benefits have been demonstrated: improved metal grade control, reduced metal losses, reduced processing time, and improved personnel safety. SemtechÆs OPC is a non-intrusive technology which relies on the fact that the composition of the vapour phase above a high temperature melt is closely related to the instantaneous status of the melt. This enables on-line real-time analysis of the furnace melt to accurately determine melt status and in particular reaction endpoints. Originally developed for on-line monitoring of copper converting in a Pierce-Smith vessel the field of applications for the technology is steadily growing. This paper introduces the Semtech OPC technology; discusses various applications and outlines the demonstrated benefits.

Jan 1, 2002

Recent exploratory work has greatly enlarged our knowledge of the geology of the sedimentary basins of Western Australia. The most pros-pective of these for oil explorati on are believed to be the Canning, Carnarvon, 'and Perth Basins.The search for oil. in, the Canning Basin has fora the most part been concentrated in" the western part, where four main structural units are now recognized - the Lennard Shelf, Fitzroy Trough, Jurgurra Terrace, and-South Cariizin.g Basin. Of these the Leonard Shelf may. be the'most prospective. The principal objective on the Shelf is the Devonian sequence, which in-cludes well'developed reef complexes. The Lower Carboniferous is regarded., as a further objective, as it contained small quantities of oil in theMeda No. I well.In the. Carnarvon Basin most explorati on has been conducted in the coastal belt of'Tertiary folding, especially in the Cape Range-Rough Range area. -The discovery of oil in the first test well. drilled.in the-basin - Rough Range no. 1 - raised great hopes, for the quick discovery of a ecmuercial field. However the other wells on Rough Range have been dry, and no discoveries have-been made in the-wells drilled on other anticlines.in the basin.

Jan 1, 1962

This paper describes a steam outburst in a metal mine which occurred in December 1992 in Japan, resulting in two fatalities. The outburst occurred just after blasting in a heading face 600 m below surface (SL-50 m), 1664 m from a mouth of the mine. The scale of the outburst was large and the fragments of the outburst spread up to 34 m from the face, the total volume of the outburst was estimated to be 206 m3. The outburst materials were mostly clay originated from the typical surrounding rock of sulfide ore and basalt. The shape of the larger outburst fragments were slabs with a thickness of 10 to 20 cm. The victims were found in a main ventilation air shaft, 175 m and 380 m from the face, respectively. The mine mainly produces copper, lead and zinc. The face was ventilated by a 560 mm diameter duct with a fan and the strata temperature of the rock was estimated to be in the range of 120 to 140¦C. There is a famous hot spring near the mine. A thorough investigation into the unprecedented accident was made including an on-site inspection and investigation of rock characteristics in laboratories.

Jan 1, 2005

By Restarick CJ

Plant data are presented which indicate a relationship between flotation rate constants and pulp density in zinc cleaning circuits at Broken Hill. The data were obtained from down the bank sampling of cleaner and recleaner banks at North Broken Hill and New Broken Hill Consolidated Concentrators. It was found that, under normal plant operation, flotation rate constants increased at the lower pulp densities existing in the later cells of cleaner banks. The addition of dilution water to the feed to the bank increased flotation rate constants, thereby confirming the relationship. It is shown that the relationship between flotation rate constant and pulp density is size dependent, being most pronounced for larger sized particles. In contrast, the effect is not markedly dependent upon mineral type. Possible consequences of this relationship for control of cleaner operation are discussed with the aid of some simulated results.

Jan 1, 1978