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Increasing use has been made of engineer ing geology and hydrogeology in the development of the infrastructure for mining projects. The Geological Survey of the Department of Mines, the Department of Main Roads, the Irrigation and Water Supply Commission and private consulting organisations and mining companies, employ spec- ialist staff to carry out engineering geological and/or hydrogeological investigations. Such in- vestigations have been of assistance in recent mining developments in northern Queensland, in- cluding those in the Cloncurry - Mount lsa, Weipa, Greenvale and northern Borten Basin areas.

Jan 1, 1974

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

This paper presents a summary of tools and methods used for geotechnical assessments and monitoring systems at block caving mines. A critical review of these tools is given based on the authorÆs experience in block caving operations. The reviewed tools include cavability prediction, fragmentation evaluation, geotechnical monitoring systems, numerical stress analysis and others. Some of these tools have been developed under certain circumstances in particular mines and experience shows that their applications under different geological and mining conditions have often been difficult. Examples from block cave mines are also utilised in this paper to illustrate the importance of the further development of these tools, whilst possible improvements on these tools are also suggested.

Jan 1, 2000

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

By Shinnosuke U, Zhang HE

In this paper, it is shown that the higher the pre-activation concentration of copper ions in pulp, the larger the adsorption amounts of copper ions and xanthate on arsenopyrite surface, and the better the arsenopyrite flotability in strong alkaline medium. On arsenopyrite pre-activated with cupric ions, the xanthate adsorption density in strong alkaline medium is approximately equivalent to that of cupric ions. It is therefore concluded that an amount of copper ions adsorb on arsenopyrite surface first, and then an amount of xanthate can (and only can) adsorb dependently on the surface active sites produced by these adsorbed copper ions on the mineral, so that arsenopyrite is kept rather flotable and is hardly separated from pyrite even in very strong alkaline medium. Selectively wiping out the surface copper active sites on arsenopyrite is the key point of successful separation of pyrite from arsenopyrite. According to this theory, a new 'SZLI' (know-how) method was recommended to satisfactorily deal with the difficult separation.

Jan 1, 1993

By Baafi EY

Deposits of gold, silver and other precious metals often display a high variability of grade values, usually a very low average metal content and are frequently not easy to sample reliably. The characteristics, together with the volatility of precious metal prices, make evaluations of precious metal deposits extremely difficult to make. Geostatistical estimation techniques can be used to make grade estimates of precious metals and to assess the reliability of these estimates. Two case studies are presented.

Jan 1, 1987

Optimisation of mining projects is directly related to effective and efficient management of risks through the life cycle of mining projects. Effective and efficient management of risks must include explicitly all aspects of Occupational Health and Safety (OHS) through the life cycle of mining projects. This paper presents a different scale of OHS in the context of the optimisation of mining projects. Meaning of risk through the project life cycle is explained. Complex relationships between numerous risk, safety, knowledge, culture and change variables, and project life cycles are shown. The key element developed in this paper is a multi-disciplinary knowledge base that is necessary for constructive development of risk management and OHS models through the life cycle of mining projects.

Jan 1, 2003

By James DG, Turner JH

This paper describes laboratory testwork for the beneficiation of a medium grade iron ore, using Wet High Intensity Magnetic Separation (WHIMS). Factors leading to the selection of machine type for this method of separation are discussed and the design of the WHIMS section flowsheet of an iron ore beneficiation production plant are described including methods to achieve operational flexibility and adequate protection of the WHIMS separating chamber. The results of the commissioning and operation of the production plant over several years are described, together with experience developed in plant operation. Data on recovery of hematite over the full range of size fractions treated is presented and compared with data in the literature. Potential methods of improving plant performance are discussed. KEYWORDS: Iron ore beneficiation, plant design, wet high intensity magnetic separation.

Jan 1, 1993

The patterns of occupational health pro- grammes in mining and metallurgy are discussed in relation to the impact of chemical and phy- sical hazards on the health of workers in these fields. Mining and metallurgy are quite unique in that their history and practice embrace virtually the total spectrum of occupational health problems and hazards as understood today. A panoramic concept of the possibilities would comprise the following fields: 1. The Pneumoconioses or Dust Diseases. 2. Physical stress due to exertion, and exposure to heat and humidity in deep mines. 3. The toxic effects of various metals in the mining of ore. The most obvious are lead, mercury, arsenic and manganese. 4. Diseases associated with mining. These include leptospirosis, ankylostomiasis and mycotic infections of the skin. 5. The Beat Diseases of coal miners working in narrow seams. 6. Illumination problems and miners nystagmus. 7. Geographical and climatic problems

Jan 1, 1975

Capital expenditure on sampling and blending is often very difficult to justify. The costs are easy to estimate but the benefits likely to be obtained by constructing good sampling and blending facilities are generally difficult to estimate. For instance, improving blending of the ore feed to a smelter would improve throughput, yield and controllability ... but by how much? Similarly, better sampling would allow processing conditions to be dynamically adjusted and would improve extraction ... but by how much? Predicting benefits often requires the use of simulation models which carefully distinguish between true grades, predicted grades and observed grades. The parameters of these simulation models must often be estimated from rather inadequate information. These difficulties are illustrated using three scenarios.

Jan 1, 2005

Portland cement is a finely ground mineral powder obtained by intergrinding a mixture of 95 parts of clinker and five parts of gypsum. It is the generic name for hydraulic cement a man made product which hardens in the presence of water. Today's cement started formally with a patent granted in 1824 to Joseph Aspdin, a Leeds bricklayer. He called his patented cement 'Portland' because it resembled a gray brown stone quarried on the Isle of Portland off the coast of England. The first cement to be made in the southern hemisphere is accredited to Nathaniel Wilson, a pioneer farmer who with his brother John began experimenting in 1874 with the limestone on their property near Warkworth. In 1884 they produced the first Portland Cement to be made in this part of the world.

Jan 1, 1978

By Maru Y

The use of mercury for amalgamation has been an integral part of the small-scale gold mining industry in developing countries owing to its low investment cost, simplicity of the technique and high gold recovery. However, its impact on health and environmental hazards have not been given the attention they deserve. In spite of the growing awareness and concerns over the mercury pollution problem by regul-atory authorities, precautionary measures such as bans on the use of mercury in some countries have been largely ineffective.This paper first reviews some of the mechanisms of mercury poll-ution, and mercury toxicity which varies according to its oxidation state. It then describes how mercury released to the atmosphere would go through the "Mercury Cycle". Compar-isons have also been made with previously measured mercury levels in small scale Papua New Guinean miners with their counterparts in other developing countries.

Jan 1, 1994

By Floyd JM

Conventional smelting reactor systems were designed to recover only one main element from their feedstocks. They did not possess sufficient flexibility to allow optimisation of co-production of multiple values from a complex feed.New reactors such as Sirosmelt and Top Blown Rotary Converters are providing new possibilities for making separation between components and this is of great significance for the complex feeds which are becoming prevalent in the metal extraction industry.Process routes using chemical procedures which take advantage of the flexibility of these reactors will be discussed in relation to a number of possible feedstocks.

Jan 1, 1985

By Hughson B

The need to prevent the sterilisation of coal stems directly from the fact that it is a non-renewable resource. In N.S.W. a vast amount of coal resource is located under major public utilities such as freeways, railways, stored waters, pipelines carrying gas, water and sewage, and transmission lines. Total extraction has occurred under freeways, transmission lines and pipelines with little or no damage. Where damage has resulted, the cost of restoration was only a small fraction of the value of the coal recovered. However, coal at present is being sterilised and perhaps lost for ever under stored waters and railways. If engineering solutions are available for mining under these improvements economically and with maximum safety, then coal should be extracted and utilised to the benefit of the State.

Jan 1, 1986

Comalco's Bell Bay smelter produces some 94 000 t.p.a. of primary aluminium in the form of foundry alloys, extrusion billet and rolling blocks. The extrusion billet and rolling block are produced by a process, in which molten aluminium is poured into an open ended water cooled mould of the required shape. The bottom of the mould is initially closed off by a dummy or starting block. Primary cooling takes place at the mould wall and secondary cooling is achieved by direct water sprays onto the out side shell of the product. Careful preparation of the molten alumin- ium is essential if stringent alloy specific- ation limits are to be met. Optimum casting temperature must be maintained within a narrow range and metal cleanliness is important to ensure a consistent product. Increased demands of recent years for larger product and higher standards of surface quality and dimensional control have been instrumental in forcing improvements in furn- aces, casting machines and in mould and dummy Doq,

Jan 1, 1977

By Moore R. F, Macias L. F

The Filbara region of northwestern Western Australia contains several known occurrences of mafic/ultramafic rock assemblages which may host platinum group element (POE) mineralisation. This paper deals with occurrences at Munni Munni and Andover. The Munni Munni complex is of particular interest because it is known to contain PGE mineralisation and is currently undergoing active exploration. The US/Australia Joint Scanner Project of October 1985 collected airborne scanner data for the BMR over Munni Munni. Such an ultramafic-mafic complex had not been previously researched with advanced remote sensing instrumentation. Extensive investigation of data from the NSOO1 (Thematic Mapper Simulator) scanner resulted in successful differentiation of gabbroic and ultramafic rocks, and also subdivision within the ultramafies. Similar differentiation could not be achieved using conventional Landsat MSS imagery and aerial photography. Encouraged by those results and in support of BMR field research into the mafic-ultramafic suites of the region, data from the Landsat Thematic Mapper (TM) instrument were investigated to attempt differentiation of the ultramafic and mafic rocks in the Andover complex some 50 km to the northeast of Munni Munni.

Jan 1, 1988

This paper examines the methods and people required for the evaluation of project or corporate acquisitions. Experience over the past five years has shown that some growth can be achieved by carefully evaluated acquisition of gold projects within regions where the acquiring company has gold processing facilities. Many Western Australian companies have participated in this process and the trend seems likely to continue with a diminishing number of larger producing companies controlling through joint venture or direct purchase of widely spaced ore deposits. In some cases the acquisition may include ore processing facilities, however an increasing number of smaller project acquisitions, involving small open pit gold deposits, which are within trucking distance of the acquiring company's mill. Whilst gold prices remain at the current depressed level we can expect to see this trend continue.

Jan 1, 1989

By Mark C. J

Since the commissioning of the BHAS Copper Plant in 1984 the copper electrowinning operations have not fully met expectations. During 1988, a laboratory scale electrowinning unit was constructed to enable an investigation of the effects of process parameters on copper cathode deposition and quality. The process parameters investigated were copper concentration, acid concentration, current density, electrolyte temperature, electrolyte flow, electrolyte impurities and electrolyte additives. The findings of this research program indicate that there is an optimum cathode deposition morphology which results in good quality copper deposits which have improved stripping characteristics. All of the process variables investigated influenced the copper deposition and therefore it was necessary to delineate a suitable operating envelope for the copper electrowinning. As a result new standard operating parameters in electrowinning have been implemented which has enabled the production of higher quality copper cathodes with improved stripping characteristics.

Jan 1, 1989

An extensive railway construction prog- ram in the People's Republic of China has required the excavation of many tunnels in difficult ground, particularly in mountainous regions. Conclusions drawn from case histories permit guidelines to be formulated as to the optimum location of tunnel alignments in faulted and folded terrains, and also in karst regions. Geological factors adversely affecting durability of tunnel linings can be minimised by adoption of appropriate construc- tion practices.

Jan 1, 1987

To enable AN-FO .tòo' be used on an equal .weight basis wish Nitro Gl reerin.e expl3oòsives r smaller diameter bore holes became necessary With consequent modifications to drill steel and burden on holes, De't'onation of AN-FO "in small diameter holes proved successful' both with 'and without primer charges but some altorat-ions were required to. adopt Anolodeòr.s to the smaller -holes, Important factors in training all operators In the new charging method were the retention of imp-,cved, fragmentat'ion, avoidance of excel ive ove:break and keeping wall rock dilution 'to an absoluato mi. iArurle ò The ò successful storage of Ammonium 14t-rate in c"!ime.tic conditions 'with daily'.-' temperature fluctuationc above and below the critical' 90¦F, has. been "achieved,

Jan 1, 1964