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By Julian Wills

The Candrill was developed with Soredem as a one-operator rockdrill for Canadian narrow vein mining. It provides the benefits of increased drilling rates, lower noise and vibration, mass reduction of 20% and system cost saving. The Candrill is to be commercialised at the end of 2001 together with a stoper drill through Parts Headquarters, Novatek's Canadian agent. The Candrill or pneumatic drills may be further exploited using a simple mechanised drilling system to further reduce operator labour, improve drilling speeds by up to 50% and to enhance drilling accuracy. Novatek's drilling system for simple mechanisation in gold and platinum mines is integrated with roof supports, can operate in stope widths as low as 800 mm and has resulted in labour savings of 50%, improved advances per blast of 20 to 50% and improved operator safety and ergonomics.

Oct 1, 2001

By Edward D. Thimons

The Bureau of Mines developed a stopping design that allows the stopping to be blown down by strong blast forces without incurring any permanent damage. Trials with the new stopping, dubbed the quick-fix blowout stopping, have been conducted in the Bureau's Safety Research Coal Mine at Bruceton, Pa., and in two New Mexico uranium mines. Results have been favorable in all cases. Compared with conventional brattice stoppings or wood bulkheads, the quick-fix blowout stopping is easier and less time consuming to install, is easier to maintain, and in most cases is just as efficient an air barrier. There is same indication that the shape of the stopping makes it more resistant to blast fore s than the fabric stoppings now in use.

Jan 1, 1976

By Peter R. Whiteley

"This paper discusses gaseous, solid and liquid injection technologies employed in the aluminium industry. The reasons for injection systems are presented, together with a description of the processes used. This includes a review of injection in crucibles, furnaces, launders, and into special purpose metal treatment boxes. The paper covers both the primary and secondary aluminium industries. IntroductionMany injection technologies are used in the aluminium industry and are in a rapid state of development. This paper provides a review of these systems and presents some thoughts on the possible future application of injection to further improve productivity and reduce losses associated with current applications.The Needs for InjectionThere are many issues facing the process metallurgist in the aluminium industry which call for the application of injection technologies now and in the future. In order to categorise these issues the industry may be broken into primary and secondary aluminium, although some of the concerns occur in both areas.The forementioned issues are variously concerned with improving metal quality, improving productivity, and reducing process problems.The use of injection techniques will be discussed under the heading of solid, gaseous and liquid injections, and the objectives and benefits of each covered briefly."

Jan 1, 1996

By N. Kubo

Sumitomo Toyo Copper Smelter and Refinery was commenced in 1971, and its production capacity of sulfuric acid was 550tpd at the beginning. In 2001 Toyo Copper Smelter and Refinery projected to expand its copper production capacity to 450,000tpy, and now the project is still in progress. To achieve this expansion project, 4,000tpd of sulfuric acid production capacity is necessary to the acid plant. So as a part of this project, the construction of the new converting and absorbing line and the improvement of the existing converting and absorbing line were carried out from 2001 until 2005. Then the production capacity of these 2 lines has already reached the target, 4,000tpd of sulfuric acid. Moreover, at the design of the new line, we adopted several latest technologies and materials in order to construct the world's leading acid plant. Basing on the operation performance of the new line, we have improved the existing line in 2005. Both of these 2 converting and absorbing lines are working quite well and contribute to big energy saving and excellently stable operation. Cu2007

Jan 1, 2007

By R. D. Brown

For the first time in years, the spring budgets of federal and provincial governments have not brought down major new proposals affecting the tax burdens of the mining industry in Canada. It seems appropriate to use this unaccustomed period of tranquility to set out an extremely abbreviated summary of the principal features of the federal and provincial income and mining tax rules affecting the mining industry.

Jan 1, 1977

The Mt Muro gold and silver deposit in Central Kalimantan has been in production since December 1994. The geology is characterised by narrow high-grade lodes containing gold and significant amounts of silver. From a largely untrained workforce in the grade control department, production per crew and per geologist has tripled during the three years of production. Grade control drilling evolved from blast hole sampling to reverse circulation sampling. National geologists are trained in basic modeling procedures. A fully integrated reporting and reconciliation system was programed and implemented.

Jan 1, 1997

By Daudi R. Waryoba

Keywords: Wire Drawing, OFHC Copper, Recrystallization, Orientation imaging Microscopy (OIM), Texture inhomogeneity Textural inhomogeneities have been investigated in oxygen free high conducting (OFHC) copper wire drawn at room temperature to a true strain of 2.31, and isothermally annealed at 250°C and 750°C for annealing times ranging from 10 s to 1 hr. Local orientations were mapped by means of orientation imaging microscopy (OIM). The microtexture of the drawn wires showed a strong <111> + weak <100> duplex fiber texture at the inner core, whereas the mid and surface regions had a comparatively weak texture. Annealing at 250°C resulted into a recrystallization which originated from the mid section, proceed towards the surface regions and ends in the inner core. Recrystallization resulted into a strong<100>+weak<111> duplex fiber texture. A similar textural inhomogeneity was observed during short annealing at 750°C. However, prolonged annealing gave rise to abnormal grain-growth that proceed from the inner core to the outer surfaces with a dominant <111> fiber component at the inner region and mixed components of <111>, <100>, and <112> at the outer surfaces.

Jan 1, 2005

Rope guides, consisting of ropes spanning between anchor points at the top and bottom of shafts, have frequently been considered as a viable alternative to fixed guides, comprising buntons and guides. However, their design has generally been based on empirically derived rules, arising from European hoisting practice of 50 to 100 years ago. This paper describes a recent technology development project aimed at defining and quantifying the important forces acting on rope guided conveyances, calculating the resulting displacement of the conveyances and assessing whether the displacements are acceptable or not. The paper describes the derivation of aerodynamic force coefficients based on CFD analyses and other significant forces acting on the conveyance and rope system. The conveyance displacements may be calculated using computer simulation of the mechanical system, or approximately using simplified equations given in the paper. Measurements taken to confirm the suitability of the proposed formulation are described. The combination of displacements and assessment of the rope guide system design are proposed, based on the ratio of design clearances and the predicted displacements.

Jan 1, 2005

By K. J. Sollman

With an ongoing concern for safety and health in the workplace, NYCO® requested three medical evaluations be undertaken to study possible health hazards of wollastonite. Two of the evaluations were conducted by the National Institute of Occupational Safety and Health (NIOSH). One was in 1976 (Ref. 1), and the second in 1982 (Ref. 2). The aim of the two studies was to answer the following two questions: 1. Do wollastonite workers exhibit more respiratory abnormalities than workers not exposed to wollastonite? 2. Is there a relationship between prevalence of respiratory abnormalities and accumulated expo-sure time to wollastonite?

Jan 1, 1988

By P. N. Vernon

Ausmelt top entry submerged lance technology offers a cost-effective means of carrying out a range of base metal smelting operations with minimum impact on the environment. The system is capable of using a range of fuels depending upon local costs. Due to the intense, localised reaction zone, high energy efficiency is obtained and the physical size of the plant is relatively small compared to that of most competing technologies. Capital cost can thereby be minimised. The furnace is well enclosed, such that fugitive emissions and ingress of diluting air to the gas stream are both minimised. The oxygen potential in the slag can be varied over a wide range such that the system can be applied in both oxidising and reducing duties. Following a general description of the technology, the paper discusses Ausmelt plants already in operation. The application of the technology for the provision of additional smelting capacity, for the improvement of converting operations and for slag cleaning is then described. A brief explanation of how these processes could be applied at southern African smelters is given and the paper closes with an assessment of novel Ausmelt applications for this geographical region, such as zinc recovery from sulphides.

Jan 1, 1997

Investigating blast vibrations typically utilises scaling and attenuation models for prediction of vibration amplitude over a range of charge weights and distances. A number of generalised relationships have been established from many years of far-field data analysis, where small changes in charge weight and ray-path distance are less critical. Under far-field conditions, small variations in local geology or geometry do not significantly affect the vibration scaling behaviour over an expected range of data. In the near to intermediate-field (less than 5 times the explosive charge length), small variations in wavepath and rock mass conditions between a blast and a monitoring point can greatly affect the outcome of vibration modelling. This case is especially true for underground blasting in sublevel open stoping, where the paths of blast-induced vibrations regularly encounter voids and preconditioned ground.

Jan 1, 2010

ALTHOUGH everybody is familiar with coal, few persons have an exact idea of, the great impor-tance of this precious fuel. Coal is the black bread of industry. Without it, industrial activity is much restrained; and so the great industrial countries of Europe and the United States of America are the great producers of coal. The 1913 production of coal in Belgium was 22,842,-000 tons, valued at 418,700,000 fr., nearly a half billion. In 1919, it was 18,483,000 tons, about 81 per cent. of the production before the war; in 1920, it had reached 22,414,000 tons, approximately the production before the war. To show the importance of coal production of Belgium, let us say that the coal industry employed 168,000 workers in the year of 1920, the metallurgical industry only 129,000 and the textile industry 103,000. The coal industry, then, employs the greatest number of workers. The value of the coal production in 1919 is estimated at 1,121,000,000 fr. On the basis of the production before the war, the value of the production of iron in 1919 would have been 701,000,000, of finished steel 1,086,000,000, and of zinc 415,000,000; therefore, in 1919 the value of the coal industry was greater than that of the metallurgical production.

Jan 8, 1922

By E A. Mitchell

In the fall of 1961, Cominco dis-carded its long-established system of feeding the lead blast furnaces by narrow-gauge tram and V-cars, and installed an elevated monorail bucket system. This system automatically loads buckets of sinter, along with the correct proportion of coke, and delivers them to any of several designated furnaces. Direct labour usage has been reduced by nine men per day; improved coke proportioning has been achieved; and a major safety hazard has been eliminated. Introduction I N THE fall months of l 961. the system of feeding the lead blast furnaces at the Trail, B.C., smelter of The Consolidated Mining and Smelting Company of Canada Limited was altered from the tradition-al narrow-gauge railway and V-car method to one employing mono-rail carriers. The change was in keeping with a recent trend at Trail to replace narrow-gauge tramming with alternative methods of materials handling. In the case of the blast furnace feeding, the

Jan 1, 1963

By Paul E. Scheerer

Synthetically produced magnesium hydroxide serves as the precursor for much of the magnesium oxide produced in the world today. Magnesium oxide, in a variety of physical and chemically reactive forms, is a very important commodity. It is used as the main component in refractories employed in steelmaking furnaces and in many base metal refining furnaces. In the chemical industry, it serves as a raw material in the production of epsom salts, rayon acetate, oxychloride and oxysulfate cements and magnesium sulfonates. It is a minor component in fertilizers and animal feeds. It serves as the starting material for producing fused magnesia, used as an electrical insulator in electric heating elements. It is employed in the magnesium sulfite process for pulp digestion in the paper industry. Additional uses are in SO2 scrubbers, as a neutralizing agent in the tanning industry and as a component in rubber compounding. Magnesium oxide is produced not only from synthetically produced magnesium hydroxide. It is produced from natural magnesites, natural brucites, and natural and synthetic hydro-magnesites. Synthetic magnesium hydroxide, as a starting material provides more control of the chemical purity and chemical reactivity of resulting magnesium oxide products because of the uniform nature, chemical and physical, of the hydroxide that can be produced. Synthetic magnesium hydroxide is produced by precipitation of Mg (OH)2 from magnesium chloride bearing seawater or natural brines through the use of a base such as Ca(OH)2 or NaOH.

Jan 1, 1978

By E. Johansson, T. Siren, K. Kemppainen

"As part of the preparations for the design of an underground repository for radioactive waste at Posiva’s Olkiluoto site on the west coast of Finland, there has been considerable site investigation work. Except the extensive surface based investigations, Posiva started in 2004 the construction of an underground characterisation facility termed the ‘ONKALO’. The ONKALO has now been completely excavated to the anticipated repository depth i.e. -430–450 m. The research conducted in the ONKALO gives further information on the bedrock and groundwater conditions of the final disposal site, as well as on the impact of the construction. The ONKALO provides an excellent opportunity to investigate the rock at tunnel scale, to conduct in-situ testing in rock, to develop excavation and final disposal techniques in realistic conditions. The ONKALO has aided in collecting the data needed, supported by a Preliminary Safety Assessment, for the application of the construction license that was submitted in the end of 2012. The target is to begin disposal operations in 2022. According to current plans, the final disposal would end in 2112 and the repository would be sealed up by 2120. The testing in the ONKALO still continues several years. This paper presents the current characterisation and research activities in the ONKALO. INTRODUCTIONAfter the Finnish Government's favourable policy decision in 2001, Posiva Oy, which is an expert organisation responsible for the final disposal of spent nuclear fuel of the owners in Finland, has focused further investigations at the Olkiluoto site, western Finland (Figure 1) and has started in 2004 the construction of an underground facility termed the ‘ONKALO’. The ONKALO is not a nuclear waste repository, but more than just an underground research laboratory URL – it is an underground rock characterisation facility. The ONKALO has now been completely excavated to the anticipated repository depth i.e. -430–450 m. In addition to facilitating bedrock research, the ONKALO also provides an opportunity to develop excavation techniques and final disposal techniques in realistic conditions. Later, the ONKALO facilities can be put into use when building and using the repository. The construction methods and materials have been selected in order not to jeopardise the long-term safety of the repository site. The findings of the ONKALO and other investigations will provide the knowledge needed for an application, supported by a Preliminary Safety Assessment, to construct a final repository for spent nuclear fuel at the site. Posiva has submitted an application for the construction licence for a disposal facility in the end of 2012. The target is to begin disposal operations in 2022 and the repository would be sealed up by 2120."

Jan 1, 2015

By R. W. Titshall

WHAT IS SAMPLING? We are all involved in sampling almost every day of our lives, by tasting, feeling, or smelling. Most raw materials, food products or manufactured items are sampled several times at various stages of the production process before a commodity of suitable quality can be produced. Data obtained from sampling is used in establishing price, quality control, allocating production costs, or overall process efficiency. The area of sampling outlined in this article is the collection of a small quantity of material from large continuous bulk flows of solids and slurries. The concern in obtaining the sample is that the material obtained is truly representative of the main flow in every respect. The methods and equipment outlined are for the collection of a manageable sample. The sample has to be analyzed in a laboratory to determine its characteristics and compliance to set standards. SELECTING A SAMPLING SYSTEM When selecting a sampling system, it is essential to define the requirements, as to what the actual sample obtained will be used for and what degree of precision is required. Determine whether or not the system has to comply with any set standards such as A.S.T.M. (American Society for Testing and Materials) which have established methods for collection of a gross sample of coal. Sampling which is done for in-plant or process control is not generally governed by set procedures, but similar care should be taken during the selection process so that when the equipment is put into service it will operate reliably and produce a sample which is truly representative of the total material lot or consignment.

Jan 1, 1982

By Charles W. Merrill

The U .S. Treasury stocks of silver have been reduced at such a rapid rate to meet industrial and coinage requirements that they face exhaustion in 3 or 4 years. Alleviation of the silver problem will require increasing supply or reducing demand. This paper examines possible long-range resource development and research programs and improved secondary recovery. The possible reduction or elimination of silver in coinage and development and introduction of substitutes in the arts and industry are also discussed.

Jan 1, 1965

By C. S. Parsons

Ore-Testing laboratories are maintained by the Mines Branch, Department of Mines, at Ottawa for the purpose of conducting experimental test and research on ore treatment. Sample shipments of a few hundred pounds to car-load lots of Canadian ores are received on application for experimental tests, and all possible methods of treatment are investigated. Reports are issued to the shipper, containing the results, with recommendations as to the most economical method of treatment. These reports have been of valuable assistance to mining companies in the preparation of plans for the design and equipment of their treatment plants. Investigations have been conducted on ores and metallurgical products from all parts of the Dominion. The ores from practically every producing mine and important mineral occurrence have been investigated in these laboratories.

Jan 1, 1931

Ranger Uranium Mines Pty. Ltd. operates an open pit mine and ore treatment plant in the Northern Territory designed to produce 3 000 tonne/yr of U308 in yellowcake from 3 500 tonne/day of mill feed. The construction of this project was completed in 1981, 12 years after the discovery of the orebody. Wright-Davy, a Joint Venture of Wright Engineers and Davy McKee Pacific, were the Project Managers and Designers of the $270 million ore treatment plant and associated infrastructure. The project was designed in Sydney in -an office integrated with the Client, staffed by 35 key personnel drawn from Wright Engineers and Davy McKee, supplemented by personnel hired for the project. The peak Wright-Davy workforce in Sydney of 200 contained 113 design staff. The design principle of using the best practicable proven technology resulted in a plant which easily produces its design output using ore types outside the design criteria. The structuring of the project systems and industrial relations policies contributed to construction being completed within time and under budget. The plant was built without any major industrial dispute occurring and no dispute arose due to the uranium issue.

Jan 1, 1983

By A. J. Petrina

"At Craigmont Mines Limited, Merritt, B.C., tests were begun in March, 1965 to evaluate the use of shotcrete as a method of ground support m development headings; previously, ail drifts had. required support, which was accomplished mainly by timber and occasionally by the use of rockbolts. The tests demonstrated conclusively the effectiveness of shotcrete for supporting Craigmont's ground. Gradually, the use of timber for ground support was virtually eliminated in favour of shotcrete. This paper describes the equipment used, the operation of the equipment, pertinent cast data and opera ting details. Also discussed are other uses developed for the shot-creting equipment, the use of reinforcing bar rockbolts, and a method used at Craigmont for lining long vertical ore passes with steel plate and concrete as part of the raising cycle."

Jan 1, 1968