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By Keren Z, Huanguo G, Jlchuan Q

In this paper, the authors introduce a new flotation technique, a double collection flotation precess, which succeeds in separating feldspar from quartz effectively in weak acidic medium (pH = 5-6). In the presence of sodium hexametaphosphase(HMP), sodium oleate selectively improves the floatability of feldspar in the first collection step. Dodecyl amine- hydrochloride is used as collector in the second collection step to separate feldspar from quartz. The flotation tests with pure minerals as well as artificial mixture give out satisfactory results. The mechanism of reagent effect was investigated briefly, which is helpful for understanding the Process.

Jan 1, 1993

The word "mine" means different things to different people. To a professional in the mining industry, it may mean trucks and shovels, overburden dumps, headframes, mill buildings, and the other conventional nuts and bolts that constitute an operating mine. To an environmental- ist it may mean bulldozed trees and tailings dams. To a mining engineer who has spent a significant proportion of his career in mine and prospect evaluation, it can mean a hole in the ground with a liar at the top. The liar in this case is frequently not so through design but through ignorance. The purpose of this paper is to contribute in a small way to en- lightening that ignorance. In doing so, it will foster more effective deployment of the pool of risk capital available to the industry.

Jan 1, 1982

By Michot LJ, Kongolo M, De Donato PH

Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Hallimond tube flotation tests and microelectrophoresis measurements have been used to investigate the reactions involved in the adsorption-ion of K-amyl xanthate on finely ground pyrite. Pure pyrite was finely wet ground, at different pH values, in specially built laboratory stainless steel or iron rod mills. Amyl dixanthogen was the only product identified on the surface of pyrite when stainless steel rods were used. When iron rods were utilised, ferric xanthate and physically adsorbed xanthate ions were observed in the superficial phase. The use of iron media was found to depress slightly the floatability of the mineral.

Jan 1, 1993

The alluvial diamond deposit in the Kimberley Region of Western Australia which became to be known as the Bow River Diamond Mine was discovered in 1982 by joint venture partners Freeport of Australia Inc and Gem Exploration and Minerals Ltd. Mining commenced in 1987. This paper describes the exploration programs and results from discovery to commencement of mining and reviews the public reporting of this process in the light of 1992 Ore Reserves Code (JORC, 1992). This case study illustrates the difficulties involved in resource estimation of alluvial diamond deposits. The study also shows that current reporting standards were, to a large extent, adhered to a full ten years before the diamond reporting section to the Code was formulated.

Jan 1, 1996

The promotion of good standards of reporting of the valuation of mineral assets in- public documents has been of concern to professional mining industry bodies, the securities industry, and. Government regulatory bodies for some time. This concern led to the National Companies and Securities Commission Release 149 (1990b) which laid down standards for Expert Reports on mining and petroleum securities, and other assets. The formation of the Australian Securities Commission provided an opportunity for a timely revision of Release 149 and the Mineral Valuation Committee was established by The Australasian Institute of Mining and Metallurgy in 1991 to review the existing code, and to develop an appropriate new Code and Guidelines.

Jan 1, 1994

By Hall ST, Miles NJ

Recently an inorganic salt, sodium polytungstate (SPT), has become available that allows the preparation of non-toxic solutions of relative densities up to 3.1. It is relatively expensive and at the higher relative densities achievable, highly viscous. Alternative inorganic compounds may in the future be identified that overcome these limitations. The Australian Mineral Industries Research Association Ltd (AMIRA) has initiated a project to examine possible alternatives. However, it has been found that by the addition of finely divided ferrosilicon to solutions of SPT, relative densities of up to 4.0 can be achieved. A laboratory technique for density fractionation of sized mineral samples utilising this finding has been developed. This is currently being extended to study the potential applications of such liquids and suspensions in dynamic systems for mineral, coal and recycled waste separations.

Jan 1, 1993

It is argued, that plate convergence, i.e. subduction, at other than right angles under a continental margin may lead to compensa-tional transcurrent faulting in the sialic environment. In this pro-cess the introduction of ultrabasic slivers, derived from the down-going oceanic crusial plate, along this fault may occur. This regi-me, both compressive overall and tensional along the transcurrent fault, will contain numerous indications for ongoing igneous and tectonic processes (such as volcanism, hot springs and frequent earthquakes).Examples for this scenario are California, the hinge between the Alpine- and Appennine orogens and the island of Sumatra.Igneous manifestations of subduction will be present both as inter-mediate intrusions and/or andesitic piles. The intermediate volca-nics may be intensely altered (chloritic, propylitic, argillic). Silice-ous breccias and banded chalcedonic sinters may be commonly found. This entire scenario is indicative for epithermal gold mine-ralisation.

Jan 1, 1990

The present practices in electro-refining of copper are shown to be the result of piecemeal and gradual improvements and innovations as metallurgists responded to changing cost pressures and the availability of new technology.Major changes were inhibited by capital cost restraints and a reluctance to build unproven ideas into new plants.It is suggested that the level of technology available today, combined with the greatest cost pressures the industry has known, call for fundamental re-appraisal and a questioning of widely accepted conventional practices.Examples of the industry reaction to changing pressures are given, and directions for future developments are suggested.

Jan 1, 1985

By H R. C Pratt, G W. Stevens

Hydrodynamic and mass transfer performance are presented for a 72.5 mm diameter pulsed disc and doughnut column of the type used by Western Mining Corporation, Olympic Dam Operation, for the extraction of uranium from sulphate media using Alamine 336 as extractant. For the present purpose, 4.0 g/L sulphuric acid was used as solute. The mass transfer data were interpreted in terms of the diffusion model, thus accounting for continuous phase axial dispersion. The results indicated that an efficiency corresponding to approximately one transfer unit over the 1.0 m height of the column was obtained. This efficiency is comparable to that observed by Gottliebsen (1997) for a pulsed perforated plate column using 173 gm/L sulphuric acid.

Jan 1, 2000

In the past five years, there has been an evolution in the assessment and control of mining risks in the New South Wales coal mining industry. This change has involved the development and use of structured, systematic, team-based risk assessment exercises to identify, assess and control unacceptable risks to people, equipment and production. The outcomes have improved the management systems in the mine. This paper discusses the evolution of the risk assessment approach in equipment design and mine operations, as well as the specific risk assessment methodology. The paper also presents the reactive side of risk management, the method of investigating failures in the management system, usually referred to as incidents or accidents.

Jan 1, 1994

The determinants of human behaviour are numerous and complex. Many scientific disci- plines focus on various processes which play some part in shaping the actions of individ- uals and groups. Behavioural science attempts to synthesise data produced by these investigations in an attempt to formulate principles by which people's thoughts, feelings and actions may be described, diagnosed, predicted and changed. While no comprehensive account of people and their reactions can be attempted in a brief paper a review of six principles does provide a framework within which managers can establish reliable knowledge applicable to all their subordinates and to themselves. This information may be used to arrange organizational environments and management practices which enable people to discover, release and increase their best intellectual, emotional and motivational capacities.

Jan 1, 1982

By Canterford JH, Ritcey GM

With the development of new technology and materials of construction, chloride-based hydrometallurgical routes have gained accept- ance as a viable alternative to sulphate-based routes. A number of commercial and pilot plants built and operated over the last decade have provided invaluable experience and con- fidence in their use. Chloride hydrometal- lurgy, with or without pyrometallurgical pre- treatment, is particularly attractive for pro- cessing complex Cu/Pb/Zn/Ag concentrates, nickel mattes and chalcopyrite concentrates. This review outlines recent developments, dis- cusses advantages, as well as indicating some of the problems still to be solved.

Jan 1, 1984

Green policies have gained momentum since the 1972 Stockholm Environment Conference. The environmental movement has influenced political initiatives both in New Zealand and abroad. Governments and international institutions have addressed local, regional and global environmental issues with varying degrees of success. New Zealand so far has not supported the United Nations' call for sustainable development in a,consistent manner.New institutions and new rules for resource management mean there are opportunities to look after the land in different and more ecologically sensitive ways than has happened in the past.The increasing influence of regional councils in resource management planning will have important implications for mining and mineral exploration. These trends are discussed and possible future events outlined.

Jan 1, 1990

By Noble AC

Ore reserve reporting practices in the United States may be broken into four general categories as follows: ò Reserve reports, often of an unofficial and preliminary nature, which are made through the news media. These are often based on exploratory drilling or sampling results. ò Reserve reports made for the purpose of raising public funds by issuing securities on the stock market, or as part of other filings to the United States Securities and Exchange Commission. ò Reserve reports to obtain private funds from banks, financial institutions, or other investors. ò Reserve reports for internal use and planning by companies operating or evaluating mineral properties. This paper discusses current practices for each of these types of ore reserves reports and reviews recent changes which have affected those practices.

Jan 1, 1987

The theme of this Annual Conference of The Australasian Institute of Mining and Metallurgy is in the form of a question: `Adding Value to our Resources - Our Future?' There are two ways of looking at this question. The first is to assume that any mineral or energy resource is worthless until it is identified, recovered and put on the market. In this sense all our current operations, be they open cut coal mines or aluminium smelters, are engaged in adding value. The question then becomes: what is the future of the minerals and energy resource industries with which we are familiar - will they grow or contract? The second way is to emphasis the value-adding aspect. The question is now one of whether or not our future depends on adding further value to resources we are currently selling.

Jan 1, 1995

We live in a world in crisis. One where the tides of change run ever faster. Where the only thing we can be sure of is change itself. The challenge we face, therefore, is not how to resist the forces that move us nor even to try to predict where they will lead us, but to harness their energy and use their momentum to find new and innovative solutions to problems that can seem intractable. Indeed, crisis is often the catalyst which energises a business to change its technology and to form a partnership with a company which specialises in pioneering new technology.

Jan 1, 1993

By Kellett KR

Gold Mining at the Lancefield Mine was commenced initially in 1897 and continued intermittently through to 1956 when rising costs and mine cave-in forced closure. The mine was redeveloped in 1981 and a new-oxide treatment plant commissioned, followed by a new refractory treatment plant in late 1982. Both these treatment plants are located within the Windarra Nickel Project plant area.The refractory ore is processed by fluidised bed roasting of flotation concentrates. This is carried out in two series connected reactors to maximise arsenic and sulphur eliminations and to minimise reagent consumption. For gold recovery the zinc precipitation process was initially used, to be later replaced by carbon-in-pulp.

Jan 1, 1984

By Nyamekye GA, Subramanian S

Adsorption tests have been carried out to elucidate the interaction mechanism between dextrin and sulphide minerals. Sulphides such as galena and heazlewoodite exhibit high affinity adsorption over the pH range that coincides with the iep of lead and nickel hydroxides, and is suggestive of chemical interaction. The adsorption behaviour with respect to the sulphides of copper is of the low affinity type, and follows a different pattern. The adsorption studies on graphite, support the chemical interaction mechanism, with the metallic impurities serving as adsorption centres. In conformity with the proposed mechanism selective separation of galena from chalcopyrite and heazlewoodite from chalcocite has been Achieved.

Jan 1, 1993

Mineral sands make up only 3% of the value of mineral production in WA. However, the distribution of mining operations, close to the more highly populated south-west coastal areas, and the wide range of land-tenures and land-uses involved has resulted in the most complex range of regulatory procedures found anywhere in the State's mining industry.Mineral sands are mined on private agricultural and "minerals-to-owner" land, State forests, nature reserves, coastal reserves and vacant Crown land. Local Government authorities, State Government departments and private landholders can, depending on the land tenure, be involved in setting the environmental conditions for mining operations and supervising subsequent rehabilitation. In the past, rehabilitation was predominantly aimed at establishing an agricultural land-use after mining; however, it is now necessary for mining companies to rehabilitate mined areas to a much wider range of end land-uses.

Jan 1, 1986

Supergene enrichment of ilmenite occurs through a complex series of reactions with initial oxidation and hydration followed by leaching and dehydration. Lateritization appears to be associated with the early phase of the supergene process and if ilmenite grains are encased in iron oxides no further alteration proceeds.

Jan 1, 1986