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By Pak DL

Over the last decade computers have become an essential element in assessing the economic feasibility of mining new mineral deposits and in assisting a variety of related support functions. A broad overview is given of the many technical application areas where computers are contributing to the mining industry with reference to work being done on the evaluation of drill hole information, mineral inventory modelling, ore reserve estimation, financial analysis, process simulation, process control, workshop job scheduling, PERT applications, and com- puter aided drafting. In all these areas the computer has greatly reduced the manual effort involved in looking at alternatives. It has had a significant effect in eliminating delays in revising calculations, or rescheduling activities to incorporate new data or cater for changing conditions, while at the same time providing more accurate and prompt information for the management decision making Process.

Jan 1, 1980

Syferfontein Colliery, part of the Sasol group of companies which specialises in the field of petro-chemical production, was established in 1990. The mine is situated about 150 km east of Johannesburg, South Africa. Two coal seams are mined, utilising two 75 m3 draglines, shovels and a fleet of 177 ton rear dump trucks. The mine will reach its full production capacity of seven million tonnes per annum in 1992. During the planning period, prior to the establishment of the mine, management were confronted with the unstable socio-political environment in South Africa which could jeopardise the eventual success of the mine. They consequently conducted a strategic planning exercise to determine guidelines for mine planning to improve the chances of success in this unstable third world environment.The strategic guidelines formed the basis for specific actions taken during the planning and commissioning of the mine. Specific actions were taken in the field of operating cost, labour relations, working environment, logistics and the general environment. First results indicate that these actions have played a major role in the success of the mine to-date. This process can be utilised by others facing similar or even totally different uncertainties.

Jan 1, 1992

By Wright R, Stock E. C

The Windarra nickel deposits known to date comprise two sulphide orebodies located at Mount Windarra and South Windarra. These orebodies, which are 15 km apart, lie within an ultramafic complex at or near its footwall contact with a banded iron formation. The Windarra deposits are 270 km north-northeast of Kalgoorlie in West- ern Australia which was the centre of a major nickel exploration programme fol- lowing the discovery of nickel deposits at Kambalda in 1966. Surface indications of the Mount Windarra orebody were discovered in 1969 by Mr. Ken Shirley while prospect- ing the Laverton area for Poseidon Ltd. (then NL). The mineralisation was loc- ated by systematic prospecting for goss- anous material associated with aero-mag- netic anomalies and ultramafic rocks. The South Windarra deposit was dis- covered in 1971 by the Union-Hanna- Homestake Joint Venture, by exploring along the strike extension of the mount Windarra ultramafic-banded iron format- ion contact. A detailed ground magnet 1. Acting Operations Superintendent, Windarra Nickel Project, Windarra, W.A. 2. Senior Geologist, Windarra Nickel Project, Windarra, W.A. 3. Mine Geologist, Windarra Nickel Project, Windarra, W.A.

Jan 1, 1973

Nearly eighteen months ago Newmont Waihi Operations joined with the local district council and members of the Waihi community in the initiation and running of a community liaison forum.   This forum û the Waihi Community Consultative Committee (WCCC) û was set up with the objective of improving communication, providing a forum for discussion and ultimately working through a range of issues relating to the future of the town and district after the projected closure of Martha Mine in late-2006.   After 18 months of meetings where all represented groups have presented their views, the challenge now is to work together to investigate likely options, seek sources of funding, produce business proposals and plan for the future of Waihi in what we call the Golden Legacy Project.   This paper backgrounds the companyÆs experiences to date, the issues the group has addressed and its proposals for the future. Methods employed to set up an effective community liaison forum are considered, drawing on specific examples from the WCCC. The actions and structures required to ensure effective and ongoing community æbuy inÆ at all levels are also discussed.   This paper develops themes addressed in Taking it to the Streets presented in 2003.

Jan 1, 2004

By Lorenzen L, Van Der P F

It is the aim of this paper to review recent research in understanding the role of cyanide in the elution of gold. Under conditions of severe pre-treatment (high temperatures and levels of cyanide), the dynamics of elution are determined mainly by the adsorption equilibrium and the flow conditions in the column. When conditions are less favourable for desorption, transport phenomena are rate controlling. The most important sub-processes of elution are the changes in cyanide, potassium and gold concentrations, as well as the change in passivation of the carbon surface. Mathematical models to simulate the various sub-processes are described briefly.The presence of an irreversibly adsorbed species such as AuCN on the carbon is determined mainly by the pH, temperature and the type of carbon. Cyanide in the pre-treatment step will convert the AuCN to reversibly adsorbed Au(CN)2. Competition between cyanide and Au(CN)z for adsorption sites will enhance the elution of gold, but plays a minor role at elevated temperatures. The most important effect of cyanide is its reaction with the functional groups on the carbon to passivate the surface for the adsorption of anionic metal cyanides and thereby promote the elution of gold. This passivation, caused by the degradation of cyanide, is strongly temperature dependent. Free cyanide in the elution step of an AARL elution is of lesser importance than the cyanide in the pre-treatment step. Elution without cyanide is possible only after cold acid washing, and has been proven on plant scale.

Jan 1, 1992

Coal mining in the Bulli seam in the Southern Coalfield in New South Wales has experienced the dangers of outbursts of coal and gas. These incidents present a major risk to the safety of mine workers and consequently a threat to the overall viability of the mining operations. Since the occurrence of a major outburst incident in the South Bulli Colliery in 1991 involving three fatalities, the primary contributory factors associated with coal/gas outbursts in the Bulli coal seam have been identified and a strategy for the management of the outburst risk has been formulated by the cooperation of mine operators, mine workers and the Department of Mineral Resources. Utilisation of risk management techniques in combination with modern gas drainage technologies and geological control methods have led to the formation of this effective outburst management plan. Clause 15 of the Coal Mines (Underground) Regulation 1999 in NSW has made it mandatory in an area of outburst to carry out mining in accordance with a code or guidelines developed for mining in outburst prone areas (DMR, 1999). In this paper an outburst management system is discussed which was developed for collieries in the Southern Coalfield that brings together all the available information including past experiences and risk management techniques in a documented form in order to maximise safety of mine workers. It is concluded that since the introduction of the outburst risk management systems in the Southern Coalfield in 1994 considerable reduction in outburst incidences have been experienced.

Jan 1, 2003

The exposed high face of Kerr's Quarry has dominated the township of Ferntree Gully for half a century. The near perpendicular face of bare dacite rock is a crumbling scar in an area of significant natural beauty. Apart from being unsightly, the face is a hazard for any person who approaches too close to its base or to the top edge. The height and the precipitous nature of this man made wall of rock is hazardous indeed. (fig. 1) The rock face is on the municipal boundary between the Shire of Sherbrooke and the City of Knox. This boundary was drawn when partition of the Shire of Ferntree Gully took place. There are many advantages in benching back the wall of the quarry but to do so the operation, located in Knox would need to extend into Sherbrooke. There are planning difficulties involved in such a manoeuvre, but during 1972, at a meeting of Cabinet Ministers, it was agreed that the matter be resolved.

Jan 1, 1976

It is a common misconception that the grant of mining tenure, whether it be an Exploration Permit, Mineral Development Licence or Mining Lease, will entitle the holder to access all land within it in order to explore or mine. The ability for miners to access their tenure in order to undertake activities is critical to the industry. While significant time and energy is quite rightly dedicated to resolving native title and cultural heritage issues before the commencement of mining operations, the same cannot always be said for addressing potential impediments that arise as a result of the overlap between mining and other tenures. Miners should be aware of the overlaps that occur with other tenure and the impact of these overlaps on the minerÆs ability to explore or produce from the area. The existence of an overlap with petroleum tenure, nature refuges, national parks, wild river areas or reserves such as aboriginal land leases are all likely to have an impact on the minerÆs ability to access the area and conduct activities. In some instances, such as an overlap with petroleum tenure, Queensland legislation encourages the miner to reach agreement with the holders of the overlapping tenure. However, in other instances, such as an overlap with a national park, mining tenure is unlikely to be granted at all. This paper summarises the impacts and impediments that arise as a result of overlaps of tenure that are likely to affect mining operations. It also provides examples of how these impediments can, if possible, be overcome under Queensland legislation.

Jan 1, 2007

It is my pleasure to deliver the first Keynote Address to the first joint conference between The Australasian Institute of Mining and- Metallurgy and The American Institute of Mining, Metallur- gical and Petroleum Engineers. I am particularly pleased to be participating in this first joint meet- ing as I have been a member of one Institute for 41 years and the other for 35 years. An examination of the membership of both Institutes confirms the fact that the mineral in- dustry is an international one. This has long been the case and basically stems from the occurrence of mineral resources in most countries of the world. It is therefore fitting that these two 'Inter- national Institutes', representing the professions involved in the mineral industry, should choose `International Resource Management' as the theme of the first joint conference. The topic of this Keynote Address is `The mineral equation' or the counterbalancing supply and demand items and the factors affecting them. I propose to attempt to present the overall picture of the mineral equation as subsequent papers and sessions will deal with specific items in more detail. My thesis is broad and deceptively simple; it is that the continued existence and growth of world material civilization depends, in large measure, on the continued use and further dis- covery of world mineral resources. Material civili- zation is used as a broad term to include the pro- duction of man's shelter and tools together with the production of the `consumer' goods and ser- vices needed by society. First let us spend a few minutes looking at the development of material civilization.

Jan 1, 1978

The following thesis is an outcome of an investigation undertaken by the writer, at the suggestion of Professor Skeats, of the dykes and associated auriferous reefs of the Walhalla-Wood's Point belt, with the view of determining what relation, if any, existed between the petrological nature and the extent of llietasomatic alteration undergone by the dykes, and the genesis and localization of the gold.Although the greater part of the writer's time in the field and laboratory was occupied in studying the dykes and auriferous occurrences, a study was also made of the general geology as a basis for the special investigation. In addition, it soon became evident in the field that secondary enrichment had played a marked part in re-concentrating the gold and some interesting data in this connection have been collected. For example, indubitable evidence has been found of nuggets of gold having been formed by secondary processes.

Jan 1, 1920

Energy is central to respond to critical stakes on human and industrial development requirements as well as on climate change. The increase of the share of carbon-free energy sources in the global supply mix will help to reduce significantly greenhouse gas emissions (GHG) as power generation accounts currently for 41 per cent of these emissions from the energy sector. In this energetic mix, nuclear and renewable energies are complementary, the first more focused in the baseload power generation whilst the second is well suited for decentralised power generation. In this context, AREVA's goal is to enable everyone to have access to a cleaner, safer and more economical energy. Regarding nuclear energy, AREVA's strategy is to capitalise on its integrated operation model, which groups together fuel cycle and nuclear power plant construction, aiming at building one third of the new nuclear capacities and securing the fuel cycle supply chain for its existing and future customers. Therefore, the front end of the uranium fuel cycle, from mining to the fabrication of fuel assemblies, has a key role in the sustainability of the nuclear industry. The replacement of the current capacity and the entrance of new countries on the nuclear power generation might lead to a significant rise of uranium demand by 2020. In order to be prepared in time, AREVA defined an ambitious industrial program to expand mineral reserves, increase the production of uranium concentrates, replace the conversion capacity, build two new uranium enrichment plants, one in France and one in the United States and upgrade its fuel manufacturing plants. To support the front-end industrial activities in the short and long term, AREVA invests on a portfolio of R&D projects to find out solutions to meet customers' needs, to improve its competitiveness and to develop new concepts and solutions to anticipate future market evolutions. In particular, some important technological challenges in mining must be surmounted to develop cost-effective methods to explore and exploit low grade deposits while creating sustainable solutions for reducing reagent, water and energy consumptions. In this lecture, an overview of the industrial investments of AREVA in the front end of the uranium fuel cycle and some highlights on its R&D major axis will be presented. This is an abstract only. No full paper was prepared for this abstract.  

Sep 13, 2010

By K L. Brown, J L. Mauk

Sulfide-rich scale occurs in steam and water lines at the Ohaaki geothennal field,Taupo Volcanic Zone, New Zealand. Precious metals show very high concentrations around areas ofpressure reduction (Au 15500 ppm, Ag 68800 ppm). Pyrrhotite dominates at the orifice plate due to low PH2s1PH2 conditions. Sulfide mineralogy in the scales is consistent with alteration mineralogy of the reservoir rocks. Separated steam then produces a mainly pyrite/magnetite mineralogy, with lesser chalcopyrite, where textures reflect high flow rates and high levels of supersaturation. This study outlines the effect that pressure and subsequent temperature decreases have on the mineralogy, chemistry and textures of sulfide scales.

Jan 1, 1998

Jan 1, 2004

About 20 percent of world gold production has been contributed by gold deposits in Archaean greenstone belts, of which ca 2100 tonnes of gold has been produced from Archaean greenstone belts in Western Australia (Phillips, in press). These deposits are, therefore, important exploration targets and an under-standing of their nature and genesis can help to formulate exploration strategies and delineate potential targets.A literature survey of Archaean granitoid-greenstone terrains indicates that a wide variety of lithologies host gold deposits. The major part of production from the Yilgarn Block, Western Australia, has come from mafic volcanics andintrusives (70% of production),with significant contributions from BIF-hosted ores (15%) and low production from sediments, felsic volcanics, porphyry intrusives and granitoids (Groves et al., in press). Similarly, most

Jan 1, 1984

Legislation up to the early 1950s prevented the mechanical extraction of pillars. The mines operating at that time had formed extensive areas of pillars. When permission for the mechanical extraction was gazetted, conventional equipment was employed for pillar extraction and generally using hand mining systems. The mid-fifty's saw the of continuous miners. These machines eliminated the disadvantages of conventional equipment and the necessity for multiple working places. Some new layouts for panels emerged; however, actual extraction methods of pillars still followed closely that of hand mining. During the early sixty's the extraction of standing or new formed pillars was undertaken by the "open-end lift" or a "split and lift" method.

Jan 1, 1974

ALTHOUGH discovered as long ago as 1817, by Strohmeyer, the use of cadmium did not become in anyway general for nearly a century. Its properties, although well known, did not recommend it to users of metals generally, and it was, on the whole, regarded more in the light of a nuisance to zinc producers than anything else. Its real value was not appreciated until both the United States of America and Germany, who are entirely dependent on outside sources for their supplies of tin, were faced with the unpleasant fact that their tin stocks were being rapidly depleted, with practically no prospect of having them replenished. This resulted in serious efforts being made in the UnIted States of America to conserve what tin was available, and, as a consequence, several metals were tried in the hope that they would prove satisfactory substitutes for tin. Among these was cadmium, and it was found that cadmium could replace tin in a manner sufficiently satisfactory to permit of its use in many directions where tin had been used before.It is on this ability of cadmium to replace tin that its use became in any way general at first; but since then new avenues of development have been opened up in which its physical and chemical properties are proving their value. It is highly probable that its use will extend very considerably as time goes on. OCCURRENCE OF CADMIUM.There are several cadmium minerals known, but none of them occur in profitable quantities as ores. The cadmium of commerce is derived almost entirely from zinc minerals and ores in which it is almost invariably present in proportions which are usually very small. Cadmium behaves metallurgically almost the same as zinc, and hence constitutes a fraction of 1% of almost all spelter.

Jan 1, 1923

By P Walton, L W. Armstrong, D P. Blair

Sydney is the capital city of NSW and has a population of approximately four million people. Eighty per cent of the cityÆs water is supplied by Warragamba Dam, which is situated some 75 kilometres south west of the city centre. A risk assessment was carried out on the dam and future predictions of water flows into the catchment area showed that there was a risk of a one in 700-year flood not being contained by the dam. The predicted loss of life and property damage warranted the construction of an auxiliary spillway on the eastern side of the existing dam to cater for any uncontrollable influx of water. A test blasting program was instigated and the blasting parameters were established that would lead to routine production blasting of the sandstone rock making it more cost effective to excavate. Blast induced vibrations were a concern to the owners and the dam wall and ancillary infrastructure was instrumented with sensitive vibration monitoring equipment during the test blasting phase of the operation. Once the blasting parameters were established from the testing program production blasting was carried out on a daily basis to maintain æstockpileÆ of fragmented ground for the excavation equipment. Blast vibration models were developed to predict vibration levels for more sensitive areas of the dam to give the operators more confidence in their operations. The blast induced vibration levels recorded did not cause any structural damage to the dam wall and the waveform frequencies of the blasting operation were much higher than that experienced during a recent earthquake. The integrity of the SCAÆs assets were at no time jeopardised.

Jan 1, 2001

Study on Ball Mill Grinding of a Cassiterite-Polymetallic Sulfide Ore

Sep 13, 2010

Adsorption of Starch on Kaolinite Surfaces

Sep 13, 2010

The chief use of manganese ore is in the production of ferromanganese alloys for steelmaking. Manganese ores generally occur in tropical areas, which influences the type of treatment required. Present methods of treatment are relatively unsophist- icated but demands by customers for tighter specifications will necessitate the installation of gravity concentrator at many mines At present only limited tonnages of minus j in. product can be sold hence future development will centre around methods of producing an agglomerate satisfactory to the smelter.

Jan 1, 1969