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Zinc-bearing materials containing chlorides and fluorides of alkali metals, such as electric arc furnace dusts, Waelz oxides, galvanising ashes, brass foundry and converter fumes are marginally attractive, both technically and economically, for processing by the Imperial Smelting Process or in a conventional zinc sulphate electrolytic plant. The EZINEX« Process allows the recovery of high purity zinc in cathode form from these materials, together with regeneration of the leach liquor. The process is based on a new electrochemical system which depolarises the anode reaction with reduction of the cell voltage, compared with the traditional sulphate electrolysis method. The electrolyte, based on a chloroammino complex, permits the recovery of other valuable metals present in the zinc bearing materials such as lead, copper and silver. These are recovered as a metallic cement, consequently improving the economics of the process.

Jan 1, 1993

Jan 1, 2004

In the face of intense global competition and other business pressures on coal miners, ongoing quality initiatives and continuous process improvements are needed to enhance business performance. By viewing a minesite in terms of key processes, rather then departments, and employing innovative technologies and better applying organisational resources, there exists enormous potential to achieve reductions in process cost and time.

Jan 1, 1998

By Burton E, Eaton R

The incentive to improve wear resistant materials performance is examined with respect to plant availability and recent trends in the labour force. Standard practice at Isa Mine Concentrat- ors in countering the effects of abrasive and corrosive wear is discussed with emphasis on results with more exotic materials such as ceramics and the Cr-Ni-Mo white irons. The paper updates work on rod and ball mill Linings.

Jan 1, 1978

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

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 exploration management has undergone major changes particularly in the last decade. Parallel to these changes in management, and partially responsible for them, have been the changes in governmental laws and regulations at both National and State levels reinforced by a highly competitive climate created by the exploration boom in Australia. The influence of overseas methods and approaches have been married to the Australian techniques resulting in a management climate which is not only familiar with the technical aspects of exploration, but is also familiar with the personnel, economic and legal phases associated with the expenditure of very large sums of money. The utilization of all the geosciences coupled with mathematical models and computer techniques for pre-selection and assessment of areas are now normal aids used in management decisions. Management techniques developed and being developed will ensure that successful exploration will be carried out if sufficient incentives are guaranteed.

Jan 1, 1974

The Cooperative Research Centres (CRC) Program was established and is supported by the Australian Government at a total cost of $140 million per year. Six of these centres have been established to help Australia's mineral industry: three in exploration, one in mining and mineral processing and two in extractive metallurgy. Since the CRC Program has now been in operation for five years, it is a good time to ask whether the minerals industry is being served adequately by these centres. In this paper, the performance of one CRC, namely the A J Parker Cooperative Research Centre for Hydrometallurgy, will be discussed in terms of the objectives of the CRC Program. As will be shown, the Parker Centre has made considerable progress since its establishment in 1992.

Jan 1, 1996

Aberfoyle sought to reduce Hellyer project development risk to a greater degree than usual. Consequently the ore reserves estimate and feasibility study were particularly comprehensive. A detailed ore reserve study was completed based on extensive drill core and underground sampling, large scale pilot plant work and a detailed feasibility study. Leading external consultants were used for advice on commercial matters which impact on ore reserves and to audit major technical conclusions, including the results from pilot plant work and the ore reserve estimate. Other project risks were diminished by negotiating a State agreement covering security of title, royalty formula and environmental management procedures, by obtaining sales contracts, and by analysing Hellyer's position on an industry cost curve. The task of financing the project was much simplified by the extent and quality of information available from the ore reserves estimate and feasibility study report.

Jan 1, 1990

The main objectives of this paper are to identify the main sources of coal dust and to investigate measures for minimisation of dust generated at these sources at the Bukit Asam open cut mine, on the island of Sumatera, Indonesia which uses a

Jan 1, 1994

The New South Wales Department of Mineral Resources has, since 1974, administered the Derelict Mines Rehabilitation Program (DMRP) to reduce the environmental impacts of abandoned and orphan mine sites. The application of the DMRP is presented in case studies of sites from the South Maitland Coalfield featuring residual drainage of acidic and saline water in a semi urban and rural community setting. The acidity here is typically derived from iron oxidation in shallow underground coal mine workings and in surface emplacements of coal washery reject materials. This paper presents summary information on AMD investigation, monitoring and rehabilitation. The experiences of community expectation, stakeholder consultation and peer review are discussed.

Jan 1, 2003

The activiltion of sphalerite with electrolytically generated copper ions from a copper electrode instead of the usual practice of the addition of copper sulphate was studied in the laboratory. A large surface area of copper was provided by lining three sides of a bench flotation cell with copper sheeting. The lining was connected to the positive terminal of a low voltage d.c. source, and the cell impeller to the negative terminal.Sphalerite was effectively activated by this arrangement and was subsequently floated using xanthate as the collector.Flotation results comparable to those obtained with 1 lb/ton CuS04.5H20 (0,255 lb/ton copper) were obtained using 0·1062 lb/ton of electrolytic copper and 0·488 kWh of electrical energy. The wastage of copper due to the formation of insoluble precipitates was found to be dependent on the length of time the current was passed. Maximum current was passed for the shortest time to minimize wastage.

Jan 1, 1973

The coastline is. an incomparable stretch of sea coast known as Ninety Mile Beach. Two gas pipelines and two oil pipelines carrying hydrocarbons from thb'Bass Strait fields to the markets of Australia cross this beach. They cannot be seen as they are laid in trenching stretch- ing many miles out to sea and the beach was restored to its natural state. Even where the dunes were disturbed, suitable grass was sown thus consolidating the sand and preventing erosion. Ninety Mile Beach is but one of the many key.wildlife and recreational areas that our operations must be concerned with. Others include Westernport and Corner Inlet, but the one discussed in this paper in particular is the platform area of the Bass Strait itself. Never was the old adage "an ounce of prevention is worth a pound of cure" more meaningful than in offshore oil production. All are well aware of some of the events of the past several years that resulted in large and costly oil spills. Far less is known, seen or publicised about the measures and developments that are undertaken to ensure that such events do not occur. We also have well developed plans for response in the event of an emergency situation, which can be initiated with great rapidity. Our responsibility is to ensure that with the best of engineering technology and operating procedures, spills do not occur.

Jan 1, 1971

By Manzoori AR

From a detailed combustion testing program and earlier experience with Leigh Creek coal, the Electricity Trust of South Australia (ETSA) gained a wide insight into the use of low rank coal fired boiler plant. This work is fundamental for the selection of boiler design parameters and other details which in turn determine the correct coal deposit selection for future power station development. In addition it gives boiler designers a good indication of the measures required to give reliable plant operation. Extrapolation from experience with existing plant, the designers main source of information, was not considered appropriate because of the lack of experience with similar coals. Brown coal beneficiation is also being assessed by ETSA in an attempt to improve the coal quality by the pretreatment of the raw coal prior to combustion in future coal.fired boilers. ETSA is also involved in the development of circulating fluid bed and gasification processes to determine whether these alternative processes are a more viable method of utilising the South Australian coals than pulverised fuel firing.

Jan 1, 1987

By Ritchie I

Copper minerals are often associated with gold ores. These create processing problems since cyanide solutions are not selective for gold alone. Copper minerals are also leached by cyanide, and typically each one per cent of `reactive' copper in the ore consumes about 30 kg t 1 cyanide. Once in solution, copper cyanide species create further processing problems as they adsorb onto carbon along with the dicyanoaurate ion. These problems make conventional cyanidation of gold ore uneconomic if the ore contains too much copper. As a result, methods of economically processing gold-copper ores are becoming of increasing importance.One of the more promising methods of treating these ores is by selective leaching of the gold by an ammoniacal cyanide solution, a method first described by Hunt in 1901. This method is already in commercial use in Mauritania, treating copper/gold tailings. In general terms, the addition of I - 2 g U1 ammonia to a standard cyanide leach solution causes a significant increase in gold extraction and decrease in copper extraction. However, early testwork on this system has concluded that the optimal leach conditions are critically dependent on ore composition, and the mechanism is not well understood, making predictions of best conditions impossible.

Jan 1, 1997

'Nothing happens until something is sold' This statement is not original - it is a necessary orientation for marketing industrial minerals. The most important single philosophy of marketing is that it recognises the consumer as the starting point. Production orientation is concerned with producing products that the customer might buy. Market orientation is concerned with finding the needs of the customer and how they can be satisfied. The difference between the two approaches can be recognised in company structures but the most tangible difference is in the approach by a company to selling and development. In other words, it is the market that decides what can be done with a mineral. The markets requirements dictate what mineral, what grade and what price will be paid. Therefore it follows that when pricing a product we should avoid taking the basic cost and arriving at a final selling price through a series of standard markups (unless government insists on it). We should start with the price the market can stand and work backwards to find out whether you have a profitable product or one that will fail because it is too dear. Naturally a thorough understanding of production costs is necessary particularly when marginal markets are concerned.

Jan 1, 1978

Small mines exist because of a restricted deposit or a small market. With the right management at the present time the small mine can have lower total costs than larger mines. Charbon is an example of a small mine with a restricted deposit and a specialised product. The development which incorporates a unique rail loading facility and flexible coal preparation plant was achieved with a modest capital outlay and in record time. To remain competitive in future with large scale mines who seek increased production the small mine must achieve increased productivity through automation, higher speed equipment and a multiskilled workforce. Deregulation of the industry, scrapping the Coal Industry Tribunal and the Joint Coal Board would benefit small mines greatly. Management of a small operation also requires multiskills which need to be supported by outside help in the form of consultants and temporary staff. In the 21st century small mines will continue to provide a service to the market.

Jan 1, 1988

Whilst decisions to commit projects have traditionally been heavily influenced by hurdle rates for d.c.f. analysis, it is suggested that evaluation of competitors' costs may be a desirable additional tool.The MICAS system developed over the past four years is described. This computer system uses standard costs modified by District and Mine factors to allow estimation of individual mine costs. The data base contains more than 15,000 items of data and more than 6000 costs are calculated.Recent applications include use for competitive analysis, predictive analysis, statistical analysis, and comparative assessments with scopes ranging from a few mines to the whole Australian export industry. Some areas where care is necessary are outlined and potential further uses are discussed.

Jan 1, 1985

The rnunber of Cenozoic volcanoes which has already been found in China surpasses 600. An ancient Chinese tourist, Xu Xiake (1587-1641 in the Ming Dynasty), mentioned in his travel notes the volcanoes and hot 'springs in Tengchong, a country of the Yunnan Province, 400 years ago. In 1927, the geologist, Yun Zhanli, expounded generally on the recent volcano distribution in China. In the '70's, China not only accomplished aerial photography and produced topographic and geological naps covering the whole country, but also obtained a new understanding of the geographic distribution and process of development of the Cenozoic volcanoes through Landsat imagery; interpretation and ground verification, together with C14 isotope dating and analysis of volcanic rocks.

Jan 1, 1987