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By W J. Riva

This paper reviews the circumstances that led to the development and construction of a commercial-scale vertical shaft carbonizer at Conmore, Alberta. This form coking process may be regarded as having potential application in other areas. Coal pelletizing offers a promising method of decreasing coal agglomeration costs under certain circumstances. Pellets can be rolled easily from -35-mesh coal, provided that a minimum of -200-mesh coal is present. Bentonite was found to be the best binder and was most effective when added in amounts of about 2 per cent. The water content of the coal pellets was observed to vary from 18 to 23 per cent. As a by-product of this investigation, it seems possible that fine coal could be converted into stoker feed by this process. A short investigation of the effect of heating rate on the carbonization of pellets was conducted. The low maximum heating rates in certain temperature ranges, necessary to avoid crack formation in the pellets as reported by other

Jan 1, 1964

The paper will cover the basic reasons for alkaline leaching, a brief description of the circuit and the reasons for the flowsheet used. Changes made to the flowsheet, including the use of mechanical agitation of pachuca slurry, the use of oxygen and its effect on extraction, the use of lime and its effect on process economy, and the environment, will be described. A brief description of a unique semi-autogenous mill and future circuit changes will be included.

Jan 1, 1979

By R. P. Townsend

It is a widely accepted "fact" that a Koepe friction hoist is generally the best solution for production hoisting when compared to a double drum hoists. This would appear to be true if one looks at the initial capital cost of just the hoist, and also if one compares the size of the motors selected for the duty. But is this the whole story? What are the longer term costs involved in the hoist's operation, and what are the relative efficiency's of the two designs? Perhaps the Koepe hoist design enjoys a better reputation than it deserves.

Jan 1, 2011

By R. W. Brock

This subject is too broad and comprehensive to be dealt with adequately and authoritatively in this paper. It calls for the knowledge and experience of many men, but the results from such collaborative effort would be of great value, particularly if similar reports of the principal mining districts of the world were made on a standardized basis so that conditions everywhere might be directly and accurately compared. In considering conditions affecting mining in British Columbia, unfavourable as well as favourable factors must be taken into account. The unfavourable are apt to loom large and to be exaggerated rather than minimized; for it is human nature to see the blackness of the cloud rather than the silver lining; to think that one's own undertaking is beset with peculiar difficulties, and to attribute lack of greater success to out-side causes rather than to personal shortcomings. It should be recognized, however, that there is no country where the conditions for mining are ideal. The ideal mining country is the product of imagination, invested with every favourable condition found anywhere, but with none of the unfavourable conditions that are always present in reality. So if British Columbia has some handicaps to the industry, it is in good company. What is important is that the advantages compensate for the disadvantages, that the balance will compare favorably with that of competing states, for mining, like every other industry is competitive, and the cost of one's product must have a definite relationship to its price in the world's market.

Jan 1, 1924

The article presents an outline of methods and certain results of laboratory tests, underground tests and model tests, aimed at assessing performance of a powered shield support on the floor of low strength parameters. The tests were conducted within the framework of GEOSOFT project co financed by Research Fund for Coal and Steel (RFCR-CT-2010-00001). The described research works were conducted by Central Mining Institute (Glówny Instytut Górnictwa), Janina coal mine and Becker-Warkop

Aug 1, 2013

In-Situ Leaching (ISL) process plants are low cost producers for uranium deposits where the geology is suitable. In the 1970s, a three-year pilot ISL program occurred on gold ore from the Ajax Mine, Cripple Creek District, Colorado, using a chloride and iodide solution [1]. The test was halted due to poor results. With gold and silver the international ISL progress has been slow; however the potential for low capital expenditure (CAPEX) and operating expenditure (OPEX) with large low grade deposits is real. Unless the metallurgy has been demonstrated there are significant risks which could be fatal flaws to an ISL gold or silver project. The metallurgy of gold ISL projects is far from simple and it is early days with project development.

Jan 1, 2011

By O. Lundhede

Today, systems and machinery usually are designed to meet only one specific customer?s requirements. One reason for this is that underground automation and smart functions are often developed tightly together with a customer. This is natural, since risk and cost can be shared between the customer and the supplier. Nevertheless, when the automation product develops and the market increase this will cause problems: The highly specialized products will not fulfill the next customer?s demands. In order to cope with this problem, Atlas Copco works towards a common platform. Instead of designing solutions for specific customers, we will lift the abstraction and focus on standardized modules. These modules, or function blocks, can then be combined in a large variety of configurations. The benefits of combining modules into products are, for example: increased flexibility when options are available for many machines; easier commissioning and maintenance since less different spare parts and tools are needed; and easier operation since the user interfaces have a similar look and feel. This paper will present the ongoing work towards standardized modules. We will discuss how our Rig Control System (RCS) allows for modular design at Atlas Copco. RCS has number of standardized modules that are used in different surface and underground mining and tunneling equipment. These modules are also used for optional products such as, drilling, radio-remote control, and telematics systems.

Aug 1, 2013

By A. Brown

"The mining industry is no exception to the general rule that continuing research is essential to good management; in fact, because of the imperfect state of knowledge in regard to many important factors associated with a mineral extraction, mining research assumes a position of unusual importance. On the basis of a recent visit to mining research centres in a number of European countries, the author describes their organization and their role in the mining industries of these countries. Some observations are made on Canadian mining research efforts, with a view to indicating a more systematic basis of procedure."

Jan 1, 1960

By Tuula Mäkinen, Lauri Pesonen, Peter Björklund, Jouni Pihlasalo, Mikko Korpi

Outotec Direct Blister Flash Smelting technology has proved to be an efficient and environmentally friendly way to treat copper concentrates from the Zambian Copperbelt at Konkola Copper Mines' (KCM) Nchanga smelter in Zambia. The modeling of slag chemistry and thermodynamics with MTDATA software played a central role in deciding the operation parameters for the smelter. Outotec FSF Online Process Advisor is used to calculate the process parameters and to give valuable information of the process state for the operating personnel. The pre-calculated slag liquidus graphs are also integrated to the Online Advisor.

Jan 1, 2011

By Chas. L. Emery

"The laws of rock mechanics apply equally well to all rock structures, and open pits are not exceptions. The concepts and some arguments about the emphasis to be placed on various aspects of open-pit design are discussed in this article.RocksROCK can be described as a granular material consisting of grains and glue. The grains may be fragments of other rocks or polycrystalline aggregates. The glue may be ferruginous, calcareous, argillaceous, siliceous or other material connecting the grains. In a crystal intergrowth, the outer layers of the crystals in contact with each other may be considered to act as a glue. Water may be a glue in clay or a grain in a crystal structure. Air and other fluids or gases are grains if they occupy spaces in a granular mass. Such grains are functional either chemically or mechanically or both."

Jan 1, 1966

By Norman B. Davis

THE ceramic group of industries is comprised of those engaged in the manufacture of cement, glass, artificial abrasives, whiteware, including earthenware, stoneware, porcelain tableware, porcelain sanitary ware, electrical porcelain, floor and wall tile, porcelain enamel on metals, refractories of all kinds, sewer-pipe and structural clay products, such as terra cotta, brick, and hollow tile. The various sub-divisions of the industry produce a wide range of articles on which we depend for our creature comforts from day to day, perhaps to a greater extent than we generally realize. The industry, in turn, depends on a great number of minerals, and chemical products derived from minerals, and it is the object of this brief paper to present a list of these with notes indicating the particular applications. In order to bring home the importance of the industry to your daily life, stop and consider the many things around you accepted as a matter of course. Cement provides the smooth surfaces of many of our highways, city streets, and sidewalks. It enters into nearly all types of construction, alone or in combination with other clay products. Glass we hardly appreciate because we can see through it so easily, but it is there to serve us in windows, doors, and other light-transmitting structures. Glass is the universal means of transporting liquids and beverages, our beverages are usually served in it, and, with the recent development in fine spun glass textiles, there is a possibility of glass clothing in the future. Chinaware, a general term for table dishes, may be earthenware (not vitrified), semi-porcelain, or bone china, but it is before us three or more times a day ?and we seldom think of the minerals that have made these products possible. Floor tile, wall tile, and other ceramic specialties for interior and exterior use and decoration please the eye and provide sanitary surroundings.

Jan 1, 1938

"Background:The recorded coal production in Nova Scotia from 1863 to 1980 was 390, 000, 000 short tons. This extraction was associated with an estimated 60,000,000 short tons of discarded material. This mining discard and coal washing plant reject are located in numerous, varying sized dumps throughout the mining areas. Approximately 70% of these dumps are in the Sydney coal field region of Nova Scotia.The coal content of these dumps varies from 10 to 30% coal with an average of 18%.Energy Costs:The explosion of energy costs in the mid-1970 's greatly increased the sale price of thermal coal which made recovery of coal from some of the dumps economical. The environmental spin-off of these operations will be the rehabilitation of the dumps upon cessation of the coal reclamation operation.Cape Breton Development Corporation, the owner of most of the dumps in the Sydney coal field was receptive to an approach by Selco of reclaiming coal from their dumps. The technology to be used, had been developed by an associate firm in the United Kingdom on similar mine dump situations."

Jan 1, 1983

By K. Cybulski

Coal dust explosions still remain the main hazard in the coal mining sector, notwithstanding their relatively wide recognition compared to other hazards and the development of effective methods of prevention. Coal dust explosions are still the cause of numerous catastrophes, often leading to fatalities. Fortunately, they rarely occur, and it is for this reason that their hazardous impact is often underestimated. This problem in Poland is being exclusively solved by the Central Mining Institute, Experimental Mine Barbara. Here, basic research on the phenomenon of coal dust explosions and prevention methods is carried out, as well as investigations into the causes and circumstances of past accidents. After 15 years of no coal dust explosion accidents in Poland (1987?2002), a few coal dust explosions have recently occurred, with tragic consequences. These events have taken place not only in hard coal mines, where the presence of dangerous coal dust is the result of common production cycle, and safety measures against coal dust explosions are subject to specific regulations, but also in coal-fired power plants. This is of special concern because prior to 1987, such accidents had been been reported only for coal mines and not for coal-fired power plants. In recent years, two dust explosions occurred in Polish power facilities: the Dolna Odra and Turow power plants. In both cases, coal dust explosions occurred in the fuel supply system, but biomass dust was also involved. The explosions caused significant damage to the systems and buildings. This paper gives description and schematics of the regions of catastrophic coal dust explosions that have occurred in recent years in Poland, as well as the results of post-accident investigations, presenting the coal dust explosion hazard at the accident scene The results specify in detail the state of safety measures against coal dust explosions in light of the relevant regulations in force, including amount of deposited coal dust, content of incombustible matter in coal dust, free moisture content in coal dust, state of coal dust explosion safety zones, and state of explosion barriers. The conclusions from the site inspection and post-accident investigations presented enable us to determine locations of explosion initiation, probable ignition sources, range of explosion flames, and explosion barrier performance. A complete elimination of coal dust explosion hazard at the site of dust deposition is practically impossible to achieve. Similarly, a total elimination of ignition source, which may be related to the occurrence of other natural hazards, equipment malfunction or human errors, is impossible. The examples of tragic events that took place in Polish coal mines and coal-fired power plants highlight shortcomings and mistakes made in terms of assessment and prevention measures taken against the coal dust explosion hazard.

Aug 1, 2013

By C. Gerow

THIS paper is entitled "Some" problems, rather than "The" problems, met in selling coal, since the problems to be met in selling any commodity have to deal with an infinite number of circumstances and conditions. These are believed to be more varied in the case of coal than probably any other commodity. This is due, perhaps, to the fact that coal has been one of the basic materials in the guiding of industrial and national achievement for the past two hundred years. During this time its use has developed from a most haphazard one to uses involving all modern scientific methods, which, rather than simplifying matters as regards the marketing of coal, have added many fresh problems, and these vary according to the particular market served. Since the concern of this paper is primarily the selling of Nova Scotia coal, it is proposed to deal chiefly with some of the specific conditions met in the markets presently served by this coal. For the purpose of discussion, these markets may be considered as divided into three main groups, namely, the Maritime market, the Quebec market, and the Ontario market. THE MARITIME MARKET First of all, let us consider the Maritime market. This is a market which has been regularly served by Nova Scotia coal since coal mining became the first industry in Cape Breton, slightly over one hundred years ago. Conditions as applying to the use of coal have naturally tended to adjust themselves to the characteristics of the coal most readily available, and, therefore, marketing problems are fewer in the Maritimes than in districts where many coals of varied characteristics are offered. Up to recent years, the problems involved were chiefly those of providing satisfactory service insofar as de-liveries were concerned. However, with the speeding-up of manufacturing processes and the necessity of reducing costs to a minimum, users of coal have become interested in obtaining coal that will give the most economical service. It is, therefore, now of importance that the salesman should have full knowledge of the particular conditions applicable to each customer's use in order to deal to the best advantage.

Jan 1, 1936

By V. Gregoire

THE DEVELOPMENT by the Iron Ore Company of Canada of the Quebec-Labrador mining project, which eventually led to 'Iron Ore in 1954', involved, from the start, several distinct undertakings. Among them, the most important were: The construction of a 360-mile railway, linking Knob Lake with Seven Islands. The erection of a railway terminal, and harbour facilities, at Seven Islands itself. The building of an entire townsite at Schefferville (formerly Knob Lake) The construction of two hydroelectric plants; and, finally, The development of a sufficient number of orebodies to enable a production of 10 to 15 million tons of ore a year. Since these phases of the project have already been the subject of previous discussions, this paper will not elaborate further on them but will rather concern itself with a brief outline of the Company's current mining practices.

Jan 1, 1958

By G. C. Bateman

THE cause of silicosis and its prevention have held the attention of medical men and mine operators for many years and at the present rime the study of this disease is more than ever to the fore, even though a considerable abatement in the incidence of silicosis has been noted of late. This abatement is due to individual and collective efforts. The Industry is keenly alive to the situation and much research is being carried on. Silica dust is assumed to be a contributing factor in the cause of silicosis. How it acts progressively in the early silicoric is nor fully understood. As the study advances, more effective measures of control may be evolved. At present the Industry has three known methods of reducing the incidence: 1. By thorough X-ray examination of all applicants, with special reference to chest conditions. Those who are considered to be susceptible to the disease are prevented from entering the industry. 2. Thorough ventilation of the mine. 3. Control of tuberculosis in mining centres and removal of miners when first symptoms of tuberculosis become apparent. In 1934, the Ontario Mining Association formed a Committee, known as the Technical Silicosis Research Committee, to study and supervise work on problems related to silicosis. This Committee obtained the full-rime services of a mining engineer to carry our research work at the mines in the Province of Ontario. The Ontario Mining Association has also provided funds for the purpose of carrying on research work along pathological and biological lines. This work is being done in the Department of Medical Research of the University of Toronto, in the Banting Institute, under the supervision of Sir Frederick Banting. The Silicosis Committee work in full cooperation with the doctors in the Banting Institute and provide material from the mines for the it use.

Jan 1, 1936

By V. Aprahamian, T. Cheng, M. Tangen, R. Beauprie

The Royal Canadian Mint has implemented significant process additions since 2005. Installation of a whole new highly automated silver refining circuit has allowed recovery of physical silver from gold and silver dorés . To complement this change, a small Top Blown Rotary Converter has been in operation. On the gold refining side, a new hydrometallurgical process to recover precious metals from Miller Chlorination slag has been developed. Finally, new systems have been put in place to improve treatment of waste water, wet and dry fume and dust.

Jan 1, 2011

By Angeles Mendoza Sammet

Based on the analysis of issues associated to conflicts between communities and mining companies in Mexico, this paper suggests actions to make mining more sustainable in Mexico. Interviews with key informants and a revision of documental information available on the internet provided information on 15 cases of conflicts in various parts of the country. The issues varied from incompliance with environmental law to assassination of community members opposing mining. The analysis concludes that mining is not sustainable in Mexico. Both mining companies and the Government of Mexico can make changes to improve sustainability. Mining companies could take a proactive approach and engage in consultation with communities before starting operations. Sharing information with communities on environmental management programs and monitoring results can be a way to start building trust and demonstrate environmental commitments. Companies can implement and evaluate CSR policies to ensure that all staff and contractors are trained on them to reduce and/or prevent corruption and violations of human and indigenous rights. Only 3 of the 15 companies had clear social responsibility policies or sustainability targets, but no reports evaluating them. Complying with the law does not make a project sustainable because of corruption, deficient enforcement, and gaps in legislation. The Government of Mexico should address the following points to make mining more consistent with sustainable development. Update the mining legislation to introduce sustainable development principles and consultation. Incorporate the notion of Free, Prior, Informed Consent (FPIC) for Indigenous People (IP) on all applicable Mexican laws or regulations. The government should not grant concessions on protected areas or indigenous lands without extensive meaningful consultation with the public, IP and land owners. Finally, it is vital to increase SEMARNAT?s capacity to review impact assessment reports and inspect and monitor environmental compliance along the life cycle of projects.

Aug 1, 2013

By M J. Daniel

Comminution is the science of size reduction of brittle materials. It is integral to mineral extraction and is one of the most energy intensive processes in the mining industry. There are a number of tests used to quantify the strength of ore, which are then used to size the AG / SAG mill in circuit design. The calculated energy utilized for breakage in these devices is based on the assumptions that the materials treated are of average shape and that the processing equipment is designed to break the ore as efficiently as possible under the given operating conditions. In drop weight tests, it was found that shape significantly influences the measured rock strength. Controlled experiments with variations in blends of rock shape show that mill throughput increases with the addition of weaker shaped rocks.

Jan 1, 2012

By BARRY BANNATYNE

About 90 per cent of Manitoba's industrial minerals production is for structural materials. Most of these come from the Paleozoic rocks west of the Precarnbrian Shield, or from glacial deposits that are extensive throughout Manitoba. The major raw materials are sand and gravel, and carbonate rocks for crushed stone (and also dolomite for high-magnesia lime, high-calcium limestone for lime and Portland cement, and dolomitic limestone for Tyndall stone). Glacial lake clays are used both in cement and in lightweight aggregate. The Jurassic and Cretaceous strata exposed along or near the Manitoba Escarpment include siliceous, carbonaceous, kaolinitic and illitic shales, all of which are quarried by Red River Brick and Tile in the Pembina Mountain and Ste. Rose areas for use in a brick plant at Lockport. Non-swelling bentonite near the base of the Pembina Member of the Upper Cretaceous Vermilion River Formation is of value as an absorbent clay, and is the only commercial source in production in Canada. It has been quarried by Pembina Mountain Clays Limited since 1940. Gypsum occurs in the Jurassic Amaranth Formation and supplies much of the market for wallboard and Portland cement additive in the Prairie Provinces. Quarries are operated at Gypsumville by Domtar Construction Materials Limited, and north of Amaranth by Westroc Industries Limited. Silica sand from the Ordovician Winnipeg Formation is of glass-grade quality, and about 100,000 tonnes are produced annually by Steel Brothers Canada Limited on Black Island . It is used as a glass sand, as foundry sand, for sand blasting, and as a filter-bed sand .

Jan 1, 1984