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By Geoffrey Birch

A skilled and efficient workforce is a pre-requisite for the success of modern construction companies. The drive for improved performance, innovation and best value must be matched by the enhanced skills of the construction personnel. Training has been accepted as one of the essential cost effective elements to achieve these goals. The foundation industry demands particular specialist skills and requires focused training for its dedicated operatives. The introduction and development of specific training qualifications for the foundation sector is providing significant benefits.

Jan 1, 2000

By R. Bokotko, J. D. Miller, J. Hupka

Laboratory results from an initial study on the removal of SO2 from gas mixtures are reported using air-sparged hydrocyclone (ASH) technology. Tap water and alkaline solutions were used for absorption and the influence of gas flow rate, water flow rate and length of the ASH unit were investigated. Complete removal of SO2 was possible with very favorable kinetics. The efficiency of sulfur dioxide absorption from air using the ASH is compared with the efficiency of conventional technology.

Jan 1, 2002

By Michael J. Sapko, Gregory M. Green, Kenneth L. Cashdollar

The National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) conducted a joint survey to determine the range of coal particle sizes found in dust samples collected from intake airways of US coal mines. The last comprehensive survey of this type was performed in the 1920s. The size of the coal dust is relevant to the amount of rock dust required to inert the coal dust, with more rock dust needed to inert finer sizes of coal dust. Dust samples were collected by MSHA inspectors from several mines in each of MSHA's 10 bituminous Coal Mine Safety and Health Districts. Samples were normally collected in several intakes at each mine. The laboratory analysis procedures included acid leaching of the sample to remove the limestone rock dust, sonic sieving to determine the dust size, and low-temperature ashing of the sieved fractions to correct for any remaining incombustible matter. The results indicate that particle sizes of mine coal dust in intake airways are finer than those measured in the 1920s. This finer size coal dust in intake airways would require more incombustible matter to be effectively inerted than the 65% incombustible specified in current regulations.

By G. Bacon

The past decade has witnessed unprecedented growth in the development and implementation of solvent extraction technology in the extractive metallurgy of nickel and cobalt. Solvent extraction is proving to be a powerful tool, opening new opportunities for simpler, more cost efficient and environmentally sound metal refining processes. These advances, however, could not have been possible without the cooperative efforts between the nickel industry and the people and organizations involved with reagents, materials and equipment development and supply as well as solvent extraction research, aided by the accumulated knowledge and practical experience from the copper and uranium solvent extraction operations. This paper provides an overview of these developments and some of the challenges ahead.

Jan 1, 2002

Caterpillar said it will produce a Cat line of ac electric drive mining trucks. The world’s largest manufacturer of mining and construction equipment said the addition of an AC electric drive truck line will provide its customers with products to fit key applications. “We are very proud of the strong leadership position that Caterpillar has attained with its mechanical drive trucks, and we will continue to invest in strengthening that position,” said Chris Curfman, president of Caterpillar’s Global Mining Division and Caterpillar Inc. vice president. “We also recognize that there are unique applications that would make the addition of ac electric drive an important and attractive complement to our current truck line.” This is the largest investment Caterpillar has made in mining trucks in its history.

Jan 1, 2006

By L. A. Ruth

Vision 21 is a government/industry/academia cost-shared partnership to develop the technology basis for integrated energy plants that will, early in the 21stcentury, result in the deployment of ultra-clean plants that produce electricity and “opportunity” products. Vision 21 plants will use fossil fuel feed-stocks in combination with other domestic resources, e.g., biomass, municipal waste, and petroleum coke. Opportunity products could include transportation fuels, steam, high-value chemicals, synthesis gas, and hydrogen. Performance targets for Vision 21 plants, example plant configurations, and the key technologies that will be needed are described.

Jan 1, 2000

By J. Gotor, C. Frias, E. Delgado

The Iberian Pyrite Belt (IPB) is one of the world's largest reserves of primary sulphides containing base metals (Cu, Zn, Pb), precious metals and some special metals such as indium. Estimated resources are over 1,500 million tonnes of volcanogenic massive sulphide ores. From 1980´s Europe lives the decline in its mines mainly motivated by the low price of the metals. One aspect that contributed equally to this was the ecological disaster produced by the discharge of more than seven million tonnes from the tailings dam of Boliden-Apirsa (Aznalcollar) in 1998. Today the situation is different; the companies present in the IPB have given evidence that it is possible to reconcile mining projects and care on the environment, and the regional authorities are opening a public tender to re-start Aznalcollar mine. A new challenging era has been started at this Spanish/Portuguese mining area. This paper presents the results and preliminary economics of a project devoted to IPB primary sulphides processing through different technology approach, e.g. conventional selective flotation against bulk flotation or mixed metals flotation combined with hydrometallurgical processing.

Jan 1, 2014

By J. Humphries

With today?s turbulent markets and unprecedented global opportunities, the need to optimize net present value and internal rates of return from capital investments has never been greater. To help address the need, this paper presents an overview of the key processes and strategies for achieving maximum return from capital projects. Best practices discussed address stage gate management for project evaluation, selection, and oversight, project execution efficiency, value improving practices, operational readiness, and operational excellence. The paper also includes a model of key metrics and benchmarking with tips for application. [ ]

Jan 1, 2011

By A. A. Smithen

There is an increasing awareness of the importance of including an assessment of environmental liabilities in the preparation of bankable feasibility documents. This means that environmental assessments of proposed, existing and decommissioned mine sites have to be undertaken for the purposes of quantifying environmental liabilities and assessing potential risks. This paper examines the need for considering environmental liabilities before describing the approach adopted in undertaking due diligence studies for the preparation of bankable feasibility documents and some of the difficulties experienced. Finally, some concluding remarks are made and the implications for the mining industry are discussed.

Jan 1, 1999

By H. G. Denkhaus

Please allow me the temerity to reply to your reply to my contribution as follows: A fracture is brittle if plastic deformation is absent or, conversely a fracture is ductile if plastic deformation is present. Consequently, brittleness is specified by the degree of plastic deformation at fracture. This is the generally accepted definition. If other material properties (e.g. the quorient or the product of the uniaxial compressive and tensile strengths) under certain conditions are influenced by brittleness, or brittleness by them, these should not be called brittleness. If the one or the other author does that, he simply uses imprecise language. Even your remark, that ?Inyang and Pitt (1990) stated that the ratio of the compressive strength (sc/st) is directly proportional to brittleness?, confirms that the two quantities are not considered the same. For example:? The well known definition that a material is linear?elastic if the strain is directly proportional to the stress?does not mean that stress (measured in MPa) and strain (measured in %) are the same thing.

Jan 1, 2003

By Q. Lui, J. Oxenford

The occurrence of heavy minerals in the oil sands of Alberta has long been known and has been well documented in the literature. Unfortunately most of the researchers working on this resource have been unable to produce products that meet acceptable market specifications. This has resulted in many misconceptions about this resource. Recent efforts have shown that with some innovative approaches, marketable material can be produced and as a result it might finally be possible to realize the potential of this immense resource that, some have estimated, could contain in excess of 20% of the world demand by 2010. This paper highlights the uniqueness of this mineral assemblage and the mineral processing challenges it presents. It shows the most recent work that has resulted in the production of marketable titanium and zircon products. This paper also focuses on some of the special problems resulting from the variability in the heavy mineral suite. Of special interest is the occurrence and removal of bitumen and pyrite without adding to the sulphur dioxide loading in the regional airshed. The trend by the mining industry to develop various positions on ‘sustainable mining’ has some significance for the heavy mineral industry. Although the industry generally has an excellent track record of eventually rehabilitating disturbed ground in an acceptable manner, heavy mineral mining operations tend to have a relatively large footprint of disturbance and the industry is under considerable pressure to develop options that are more environmentally acceptable. In addition, as operators move to exploit deposits that are lower grade and/or are further from a port site, the emissions per unit of sold product will also rise and the industry will be under pressure to address this issue as well. Because heavy minerals from oil sands are by-products of existing operations, there are virtually no incremental disturbances or emissions that would be associated with heavy mineral production. All mining and tailings remediation issues are accounted for by the oil sand operation. The only incremental emissions would be those associated with the mineral processing operations and transport of finished products to a port site. This paper discusses the environmental and cost implications of this situation.

Jan 1, 2003

By John Ward Smith

Dawsonite-bearing oil shale of Colorado's Green River formation offers a unique and vast (more than 5.9 Gt of A120 j) resource of easily extractable alumina. The processing methods required by the thermal reactions of dawsonite and its oil-shale carrier also require production of shale oil, soda ash, and nahcolite as marketable coproducts. These production methods are presented. The alumina production process is contrasted with the Bayer process to describe technical advantages of extraction of alumina from oil shale which may offset the problems associated with processing a relatively lean ore. While alumina production from oil shale requires development of new technology, the technical problems appear solvable. Only the political problems arising from the now onerous and completely unnecessary federal oil-shale withdrawal appear less solvable.

Jan 1, 1982

By J. Nell

An overview is given of the matte melting process used for the beneficiation of South African platinum group metal (PGM) ores. Most producers use six-electrode furnaces to melt the concentrate and Pierce Smith converters to oxidize excess iron sulphide from the furnace matte. Concentrates from two reef types (the so-called Merensky and UG-2 reefs) dominate the feedstock supply. Concentrate from the Merensky Reef is low in chromium and does not pose significant melting problems. Concentrates from the UG-2reef contain much higher levels of chromium, which results in the formation of chromium-rich spinels during melting. This is attributed to the low solubility of chromium in furnace slag under typical operating conditions (an oxygen partial pressure of 10-8?10-9bar at temperatures of 1550°C to 1600°C). During the converting process, care is needed to avoid excessively oxidizing conditions, which result in cobalt, nickel and copper losses to the slag. High nickel losses result in the formation of Fe2NiO4 (trevorite), which often forms solid solutions with FeCr2O4and Fe3O4. In future, the main challenge in the processing of South African PGM ores will be to cope with ever-increasing levels of chromium in the concentrate. A short-term solution to the problem would be to melt the concentrate under slightly reducing conditions to promote the formation of CrO, which is more soluble in the slag than Cr2O3.A longer-term solution to the problem would be to abandon the current matte-smelting process in favour of an alloy-based process, which would offer total flexibility with respect to the amount of chromium that can be tolerated in the feed. Keywords: Merensky, UG-2, furnace, slag, matte, converting, spinel, chromium

Jan 1, 2004

By David Vergara Segura

Una empresa minera, en condiciones normales, maximiza su operación y minimiza sus pérdidas por tener operativos y equipos ligados a la producción. Por lo que es necesario la integración entre las áreas de la empresa, específicamente entre las de Mantenimiento y Logística. En este sentido, el presente texto señala la importancia del trabajo en equipo entre estas dos áreas, cuyo objetivo común es optimizar la gestión del activo que tiene un impacto significativo y directo en la producción. También se plantea bajo del esquema de una empresa minera ficticia, el desarrollo de estrategias conjuntas, y se define un modelo de gestión logístico, generador de ventaja competitiva, el cual está orientado a la optimización del uso del activo.

Sep 12, 2005

By M. Kerr, Petra Lampinen, Jinming Zhang, Petra Brodin, C. Hull, Nils-Johan Bolin, R. Asmatulu

"According to Darcy’s equation, the rate of dewatering varies as inverse square of the surface area of the particles to be dewatered and is proportional to the pressure drop across a filter cake. Thus, the difficulty in dewatering fine mineral concentrates can be overcome by using high-pressure filters. When treating ultrafine particles, however, it is often necessary to further dewater the filter cake using a thermal dryer. In the present work, novel dewatering aids that can reduce the pressure requirement have been developed. The reagents are designed to reduce surface tension, increase particle hydrophobicity and increase capillary radius, all at the same time. They were tested for dewatering mineral and coal concentrates in both laboratory and pilot-scale tests. The results show that the use of the novel dewatering aids can substantially reduce cake moistures and, at the same time, increase throughput. In this communication, the case history of using the reagents commercially at the Garpenberg concentrator is given. The use of the novel dewatering aids allowed the operators to use a vacuum filter to obtain desired cake moistures and obviate the need to use a thermal dryer.INTRODUCTIONDewatering is an integral part of mineral and coal processing operations, as it is necessary to remove water from concentrates (or clean coal) to minimize shipping costs, meet contract specifications, and recycle the process water. In general, the cost of dewatering increases with decreasing particle size, which can be attributed to the difficulty in removing the water trapped in the pores (or capillaries) formed between the particles constituting a filter cake.The various parameters affecting the process of dewatering, including the effect of particle size, can be understood in view of Darcy’s equation (Darcy, 1856):"

Jan 1, 2005

By Augustine O. Orumwense

Ball mills are commonly used for regrinding operations in the mineral processing industry. But, in recent times, efforts are being made at the introduction of stirred mills particularly for those instances where very fine grinding is required. Media type (steel shot, glass beads, alumina balls and crushed quartz), media size, mill speed and the number of passes required to obtained the target product size are studied. The product size and energy consumption are used in the evaluation of the test results. The grinding media size, shape, density, filling ratio, mill circumferential speed and grinding time play a distinct role in product size fineness.

Jan 1, 2005

By K. Spence

"The notion of “value” has always been a subjective and contentious issue. Indeed, value is in the eye of the beholder. There are as varied methods and practices for valuing property, as there are industries in which they are applied. For example, there is replacement value, insurance value, salvage value, appraised value, book value, and fair market value, to name a few, although in the mining industry, valuations usually refer to fair market value.In the Canadian mining industry, at present, there are no comprehensive regulations or guidelines that specify which approaches or methods are appropriate for use in the valuation of mineral projects. In January 1999, The Mining Standards Task Force of the Toronto Stock Exchange and the Ontario Securities Commission recommended that the Canadian Institute of Mining, Metallurgy and Petroleum (CIM) establish a committee to review and advise on approaches and methodologies for the valuation of mineral properties. Among the approaches to be considered are included the following: the discounted cash flow approach, the cost approach, the option pricing approach and the market comparables approach. In addition, methodologies differ depending on whether the project is at the exploration stage or the producing stage.The CIM Special Committee on the Valuation of Mineral Properties (CIMVal) expects that its final report will form the basis for a Canadian code or standard for the valuation of mineral properties."

Jan 1, 2002

By D. Beneteau, D. Milne

"Advances in technology provide educators with valuable tools to enhance their teaching and efficiently deliver content to larger audiences. University educators are often encouraged to become more “research intensive” and to increase student enrollment. Faced with these pressures, there is a tendency to use technology to improve teaching efficiencies rather than to enhance existing teaching approaches. Practical learning in applied engineering courses would suffer greatly if hands-on experience is not emphasized. This paper discusses advantages and limitations of new technologies applied to learning, and methods to incorporate more hands-on experiential teaching techniques to applied mining engineering courses.RÉSUMÉ Les avancées technologiques fournissent aux éducateurs des outils intéressants pour rehausser leur enseignement et livrer efficacement de la matière à de grands auditoires. Les éducateurs universitaires sont souvent encouragés à devenir plus « axés sur la recherche » et d’augmenter l’inscription d’étudiants. Face à ces pressions, il y a une tendance à utiliser la technologie pour améliorer l’efficacité d’enseignement plutôt que de rehausser les approches existantes d’enseignement. L’apprentissage concret dans les cours d’ingénierie appliquée souffrirait grandement si l’accent n’est pas mis sur l’expérience pratique. Le présent article discute des avantages et des limitations des nouvelles technologies appliquées à l’apprentissage et des méthodes pour incorporer plus de techniques expérimentales pratiques aux cours de génie minier appliqué."

Jan 1, 2016

By S. Dessureault

Computer Integrated Mining (CIMG) is a process of using computer networks to transform islands of enabling technologies into a highly interconnected mining system. CIMG involves the integration of advanced technologies at various levels in the mine business to achieve higher flexibility, better quality of processes and control, and improved profitability. Justifying the benefits of CIMG are difficult as many of the advantages are derived from improved flexibility, quality, and control. Justification is based on the evaluation of the benefits to be gained, compared to the required capital investment. Management tools used in mining are currently inadequate in assessing the value of advanced technology whose benefits are primarily qualitative. A key aspect of successful implementation is management acceptance, which has to be won through the capability to justify the technology?s financial costs and the true value of all of its benefits. The manufacturing industry faced similar justification difficulties when adopting advanced technology in factories. A significant amount of funding and research was invested in developing management strategies and approaches to justification. Many of the problems that faced the transformation of the manufacturing industry in the late Eighties and early Nineties are now facing mining. The solutions derived for manufacturing may help mining in its transition to an increased reliance on integration technology. Reviewing the industrial history of computer integrated manufacturing identifies several tools and strategic frameworks that can be adapted for mining. Keywords: Computer integrated mining, justification techniques, CIM, information technology.

Jan 1, 2004

By D. J. McCracken

During 1995, the estimated consumption of lithium minerals in the western world was 139 kt (153,000 st).This amounted to 18 kt (20,000 st) of lithium carbonate equivalent (LCE). Overall tonnage demand for lithium minerals increased by 10.8 kt (11,900 st) during 1995from 1994. From 1992 to 1995, overall tonnage demand has increased 62%, from 85.5 to 139 kt (94,240 st). There are four major producers of lithium minerals. Gwalia Consolidated in Western Australia is the largest producer of spodumene. It supplies high-grade spodumene concentrate, fine-spodumene concentrate, glass-grade spodumene and chemical-grade spodumene.Tantalum Mining (Tanco) of Manitoba, Canada, produces high-grade spodumene concentrate, fine-spodumene, concentrate and montebrasite. Bikita Minerals in Zimbabwe is the largest manufacturer of petalite. It supplies high-grade and container-glass petalite.

Jan 1, 1996