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By A. Galibois, R. Singhal

"This paper highlights some of the potential application areas of knowledge-based systems in the mining industry. The basic theoretical principles associated with knowledge-based systems are discussed and the justification for mining applications is given. The paper concludes with a brief description of a prototype knowledge-based system applied to scraper selection that was developed at Université Laval on a LISP machine. IntroductionThe beginning of Artificial Intelligence coincided with the conception and development of the first computer systems some thirty years ago. At that time researchers were euphoric about the possibility of modelling the human reasoning process. Soon, however, they discovered that the combinatorial aspect of the set of possible solutions to a particular problem did not permit an in-depth evaluation.In the mid-60s researchers started to look at the heuristic approach because it was more suited to human behaviour with its congnitive abilities (i.e. representing, reasoning, problem solving and advising). The heuristic approach allows possible results rather than exact solutions and it is more rapid and cost effective than the exhaustive combinatorial analysis. The heuristic approach did allow some noticeable progress in the seventies with the development of the first expert system called MYCIN with the objective of diagnosing blood infection diseases."

Jan 1, 1988

By P. Farsangi, A. Hara

"Kidd Creek Mines places approximately 10 000 tonnes of consolidated rockfill on a daily basis. Consolidated rockfill is comprised of sized aggregate mixed with different ratio and amounts of binders. Consolidated rockfill, with closely controlled specification, is employed for subsequent pillar recovery and improved passive active/ ground support. With the same amount of cementing agents consolidated rockfill mass yields a higher, compressive strength, modulus of elasticity, cohesion, and angle of friction compared to a typical cemented hydraulic fill mass.The consolidated rockfill at Kidd Creek Mines is designed to sustain not only the gravitational loading of the overlaying fill material, but also to some extent the dynamic loading applied during blasting of the adjacent stopes and/or pillars.The quality control of materials used in Kidd Creek's rockfill system could be effected in three stages of handling: (1) at the surface backfill plant; (2) during transportation; and (3) placement of the fill.The emphasis in this paper is placed on individual stope backfill design and quality control measures at Kidd Creek Mines to place fill in large-scale open stopes which eventually could be exposed on all four walls during pillar recoveries."

Jan 1, 1993

By Peter A. Hacquebard

"The early history of the Geological Survey of Canada is closely connected with coal geology investigations in the Atlantic Provinces. In 1843, Sir William Logan, the first director of the Geological Survey, measured the 4441m thick shore section at Joggins in Nova Scotia. Detailed mapping of the coalfields were subsequently carried out by H. Fletcher during the latter part of the nineteenth and first part of the present century. During the 1920-1940 period, the stratigraphy of the carboniferous WIZS' established by WA. Bell, who later also became a diretor of the Survey. Bell's work WIZS' followed by coal geology investigations of A.A. Hayes, W.S. Dyer, EA. Goranson, G. W.H. Norman, J.E. Muller, T.B. Haites and P.A. Hacquebord.The activities and accomplishments of the Survey geologists during the past 150 years are presented in this paper.General Outline of Survey Activities in Coal Geology During the Past 150 YearsIn 1842, when the Geological Survey of Canada (GSC) was established, the industrialization of the major countries of Western Europe and North America was actively persued. The energy required for this industrialization was obtained from the only fossil fuel then available, namely coal. The measure of a country's major mineral wealth at that time was the availability of mineable resources of coal. Eastern Canada, where mining had been carried out since 1720, was known to be well endowed with valuable coal deposits. In the major fields of Nova Scotia (Fig. I) several large-scale operations had been started during the middle and latter part of the nineteenth century.The significance of coal, therefore, was well understood, and exploration surveys specifically oriented toward coal were carried out by the Geological Survey from its earliest beginning. The first report of a detailed geological description of the coal measures of eastern Canada was prepared in 1843 by Sir William Logan (1845), the founder and first director of the Geological Survey of Canada. This early work was continued and complemented in 1896 by H. fletcher (1906), who during the latter part of the nineteenth century and first part of the present century systematically mapped the coal-bearing regions of Nova Scotia, which he considered all to be of approximately the same age."

Jan 1, 1992

By J. P. Harrison, K. Gao

It is well known that in situ stress measurements at a given site will generally display significant variability. However, it appears that a robust analysis of such measurements – i.e., one that is faithful to the tensorial nature of the data – is not available. Despite the fact that stress is a tensor, stress magnitude and orientation have long been analyzed separately using classical statistics. In earlier work we demonstrated the applicability of tensor statistics to the analysis of stress variability. Here, we investigate further the difference between tensor and classical statistics with respect to the stress tensor correlation matrix. Our analysis commences with the selection of a series of valid correlation matrices. Then, assuming that standardized tensor components follow the multivariate standard normal distribution, these correlation matrices are used to generate marginal probability distributions of the eigen-parameters (i.e., principal stress magnitude and rotation angle). From these, random stress tensors are generated, their eigenparameters determined, and the probability density distributions of these obtained using both classical and tensor statistics. Our results indicate that, for all correlation matrices, both methods give practically identical distributions for principal stress magnitude. However, the discrepancy between the two methods with regard to probability density distribution of rotation angle is highly dependent on stress component correlation. This discrepancy is usefully quantified in terms of the integral, with respect to orientation, of the difference between the two probability density distributions. This parameter, which we term Area Difference, is closely linked to the magnitude of the correlation matrix determinant, which itself is related to the normal stress correlation coefficient (i.e., ?x ,?y ??). Assuming that Area Difference should not exceed 0.1, we identify the critical determinant for any particular value of normal stress component correlation coefficient. Thus, using published in situ stress data and the obtained critical determinants, we show that for a specific normal stress component coefficient, when the correlation matrix determinant is less than its critical determinant, the more precise tensor statistics should be used to calculate the distribution of rotation angle. These results demonstrate that the customary analysis of stress measurement data may lead to erroneous results, and that tensor statistics appears to be preferred approach.

Jan 1, 2015

By Trent Hamilton

Cameco ? McArthur River Operation is a high-grade uranium mine in northern Saskatchewan. Average grades mined are nearly 20%, more than 20 times higher than other operating uranium mines in the world. The significant risks involved with mining this grade has been effectively mitigated using innovative and unique controls, implemented from development and production mining through to ore processing. The types and sources of radiation are presented and protection measures are discussed. McArthur River?s strong radiation culture is evidenced by continually low radiation exposures while transitioning to new mining zones.

Aug 1, 2010

By M. N. Pons, E. Benizri, B. Laubie, A. Bani, Université de Lorraine LRGP, P. Kidd, A. J. M. Baker

"Serpentine (i.e. ultramafic) outcrops in Europe cover more than 10,000 km2 and have a low-fertility and low-productivity, making them unattractive for traditional agriculture. In general, these areas are slowly abandoned by local farmers, affected by strong rural exodus and landscapes undergo a process of closure. However, ultramafic landscapes have the potential to provide multiple ecosystem services that can contribute to Europe’s goals towards insuring food security, production of renewable raw materials and renewable energy. Phytomining (agromining) aims at cultivating metal hyperaccumulator plants that are able to accumulate Ni and other strategic elements from metal-rich soils and transport them to the shoots (>1%), which can then be harvested as a bio-ore. Such metal-rich biomass can be used to recover highly valuable metals, e.g. nickel (Ni) and also to produce energy (heat, electricity). Nickel agromining can thus offer an eco-efficient alternative to classical pyro- or hydrometallurgical processes without disturbing the soil cover and the geology from soils and rocks that would be considered as low grade ores or sterile material for conventional mining methods.Phytomining agroecosystems can lead to better soil resource efficiency and can offer a fully integrated, new agromining agriculture that could cover thousands of km2 in Europe, benefit local communities with a sustainable rural development and provide a wide array of ecosystem services which will need to be optimised under a life cycle assessment methodology:1. Production of bio-sourced metal products2. Production of energy biomass3. Restoration of soil fertility for conventional agriculture (Ni stress)4. Limiting Ni intake by local populations and farmers5. Use and conservation of local biodiversity (plant and soil fauna and microflora) as cultivated ecosystems6. Store carbon in cultivated soils7. Enhance pollination activity at landscape level.Nickel agromining could therefore change the economical balance in historically-disadvantaged ultramaficregions of Europe"

Jan 1, 2016

By W. A. Crosby, W. K. Smith, K. L. McDonald

"IntroductionThis paper describes how the introduction of two blasting techniques and the resuItant development of new dragline digging methods have increased the productivity of single- and double-seam dragline operations at the Rietspruit opencast mine.LocationRietspruit , one of South Africa's largest opencast strip mines, is situated some 11 5 kilometres east of Johannesburg in the Witbank coal field.BusinessRietspruit is a joint venture between Transvaal Consolidate d Land and Exploration Company (T.C.L.) and Shell, South Africa. Rietspruit is administered and managed by Rand Mines, the Mining division of Barlow Rand, transportation and marketing being the responsibility of Shell. The total saleable coal product, approximately 5,5 million tons per annum, is exported via Richards Bay.Presplitting and Throw BlastingPresplitting was initially introduced in September 1980, as a means of dewatering t he overburden and mid burden to facilitate the use of dry-mix explosives a s opposed to slurry explosives.The utilization of the throw blasting technique arose as a direct result of observed ground movement after the successful introduction of presplitting. The first trials commenced in March 1981 on the double-seam operation. The methods, economics and resulting advantages are fully described elsewhere. A brief description follows.Method of PresplittingAfter determining the desired presplit line, 250-mm holes are drilled to top of coal at 4-m to 6-m intervals, dependent on the competency of the rock overlying the coal. A single 60-kg charge of slurry explosives is located at the bottom of each hole, no tamping is used and all the holes are detonated simultaneously. The results are a competent, straight, vertical highwall. This enables accurate control of the first row of blast holes closest to the highwall, which is a prime requisite for successful throw blasting."

Jan 1, 1983

By L. A. Clark, G. H. R. Burrill

"Most unconformity-type uranium deposits in Saskatchewan occur within a few tens of metres above and/or below the basal unconformity of the 1,45-b.y. Athabasca Sandstone. Graphitic basement rocks coincident with post-Athabasca faulting or brecciation at or near the unconformity are important in localizing uranium deposits which form as tabular, ribbon-like bodies with grades averaging over 2 per cent uranium and containing up to 50,000 tonnes UJOs. Some of these deposits have similar contents of nickel and arsenic.In the genetic model proposed to explain these deposits, traces of uranium were leached from the sandstone and weathered basement rocks by oxidized formation waters sweeping through the sandstone and along brecciated faults. Over basement meta-petites, a thick clay regolith adsorbed uranium from the solution. Thus fixed, the uranium was reduced through an indirect reaction with graphite, possibly involving methane. The clay mineral surfaces were thus continuously cleared to allow further adsorption. Basement faults localized along weak graphitic units were re-activated, offsetting the sandstone formation, probably at the time of an early uranium deposition about 1.2 b.y. ago, and served as vents for spent ore solutions. Fluid convection was induced by topographic relief and/or crustal heating from radioactive decay in basement plutons or mantled Archean domes with uranium and/or thorium contents a few ppm above those of adjacent rocks. Heat from radioactive decay within the incipient uranium deposit would develop in about a million years. The self-generating convection cell would continue uranium deposition until all permeability was plugged by minerals. In some instances, convection was re-initiated after subsequent faulting and brecciation. While some deposits were further enriched, heavy flows of oxidized fluids re-dissolved and partially depleted other uranium deposits.The East Alligator Rivers uranium deposits in Northern Territory, Australia, occur within Middle Proterozoic quartzchlorite and quartz-muscovite schists overlain by sandstone. Highest grades occur in silicified breccias where carbonate beds were leached out. Mineralization ages are both pre- and post-Kombolgie Sandstone, but, to date, no significant uranium mineralization has been encountered in the sandstone. There are many general similarities with Saskatchewan deposits, but important differences in detail."

Jan 1, 1981

By R Chandramohan

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 R. C. Carne, R. J. Cathro

"Most of the recent large discoveries of zinc, lead and silver in Western Canada are Paleozoic-aged stratiform deposits that occur within the limits of the tectonic sub-province of the Canadian Cordillera known as Selwyn Basin. Bounded on either side by coeval carbonate platforms. Selwyn Basin trends northwest for 1300 km from northeast British Columbia to Alaska. Paleozoic rocks of Selwyn Basin consist primarily of chert, shale and coarser-grained clastic sedimentary rocks with minor volcanic rocks.The Selwyn Basin deposits have few counterparts elsewhere in Canada, but have a close similarity in geological setting, mineralogy and morphology to well-known deposits such as McArthur (HYC) in Australia, Meggen and Rammelsberg in West Germany, and Sullivan in British Columbia. Recent studies of these deposits have led to an emerging, but now generally accepted, model of ore deposition in which stratabound zinc-lead-silver shale-hosted or ""sedimentary-exhalative"" (sedex) deposits are precipitated in active tectonic environments from metalliferous geothermal brines that rise to the sea floor along deep-seated fault zones. Although their mineralogy and ore metal zoning can be similar to that of volcanogenic massive sulphide deposits, most sedex deposits have only a weak genetic link with volcanism.Sedex mineralization in Selwyn Basin has been identified within three separate ages of shale or its metamorphosed equivalent. The lower Cambrian-age Anvil Camp in central Yukon Territory contains the only producing mine (Faro). Important lower Silurian-age zinc-lead mineralization is at Howards Pass along the Yukon - Northwest Territories border. Barite and zinc-lead-barite mineralization of upper Devonian age occurs across Selwyn Basin. Potentially economic deposits have been found at Macmillan Pass, along the Yukon - Northwest Territories border and in the Gataga District of northeastern British Columbia."

Jan 1, 1982

By Deni Côte, Marcel Vallée

"The Guide to the Evaluation of Gold Deposits reviews the successive evaluation steps in the domains of geology, engineering, and economics. The Guide analyzes, in a systemic perspective, the sequence of exploration, development, and evaluation work required to bring a mineral deposit to production. The aim is to identify the metal/mineralization losses and ore dilution that each work step contributes to the evaluation and mining process. The procedure allows one to maximize the income and profits of a mining operation, and to reduce the risks of financial losses tied to investment decisions in the mining sector. For greater efficiency, the criteria of reserve estimation and classification should be integrated with the evaluation steps and methods. At earlier stages of deposit development, when quantitative knowledge is available mainly on the geological axis, the term ""delimited mineral deposit"" should be used. The term ""reserve"" should be used only in an operating mine or in a mining project, when information in the geological, engineering, and economic domains is adequate to ensure technical and financial feasibility. ""Reserves"" are by definition ""mining reserves"". Each category of proven/probable reserves and measured/indicated deposits should be subdivided into two classes to express better the many steps of mineral valuation. The category of ""possible reserves"" shall be replaced by that of ""inferred mineralization"". This system, derived from the Australasian Code, can easily be integrated into current practices of the exploration and mining industry within a short timeframe. The proposal to develop the use of the margins of error of the estimates at a confidence level of90% should be viewed in a longer timeframe. Establishing the precision of the mineral inventories and distinguishing between categories and classes by means of the margin of error will require more work and a longer break-in period.SOMMAIRELe ""Guide d’évaluation des gisements d'or"" analyse, dans une approche systémique, les travaux d'évaluation et de mise en valeur des gisements minéraux dans l'axe de la géologie, dans l'axée l'ingénierie et dans I ‘axe de l'économique. L’objectif est d'identifier la contribution aux pertes de métal et à la dilution du minerai des diverses étapes de l'évaluation et de l'exploitation du gisement. Ceci aid erra à maximiser les revenus et les profits, et ainsi, à réduire les risques départe financière que comportent les décisions d'investissements dans le secteur minier. Pour atteindre ces objectifs, iI est essentiel de relier les critères d'inventorie et de classification des réserves aux méthodes d'évaluation des gisements. Aux stades antérieurs du développement minéral, lorsque les connaissances quantitatives ne s'étendent qu’à l'axe géologique, le terme ""gisement délimite"" sera utilisé. Le terme ""réserve"" ne sera utilisé que dans une mine en exploitation au dans un projet minier, lorsque l'information dans les axes de la géologie, de l'ingénierie et de l'économique sera appropriée pour en garantir la faisabilité technique et économique. Chaque catégories des réserves, prouvée et probable sera subdivisée en deux classes pour mieux qualifier les niveaux d'évaluation du projet. La catégorie actuelle des réserves possibles sera remplacée par celle des ""minéralisations inférées"". Plusieurs essais démontrent que le système propose, qui s'inspire du Code australasien, peut facilement et rapidement s'intégrer dans les pratiques de l'industrie. II pourrait également contribuer à une standardisation des méthodes et des nomenclatures à l'échelle internationale. La proposition d'utiliser les marges d'erreur des estimes au niveau de confiance de90%pour caractériser les estimations se situe dans une plus longue perspective. Cette application demandera des développement méthodologiques additionnels ainsi qu'une période de rodage."

Jan 1, 1992

By E. J. Marcotte

"BRIEF DESCRIPTION OF GRINDING CIRCUITCrushed ore at -5/ 16 in. is delivered by a conveyor system from the crushing plant to two 1250 ton fine ore bins. The ore is transferred from each bin by a 30 in. feeder conveyor belt, operated by a Link Belt P.I. V. (variable speed) drive, to a 24 in. conveyor that feeds the 8 x 10 Allis Chalmers rod mill.The rod mill discharges to a common mill discharge pump box. Three 6 x 6 SRL pumps are employed to pump the combined mill discharge pulp to a common distributor box which distributes the feed to two of the three Kreb D lSB cyclones in each of the two banks at a hydraulic pressure of 6 psi.The cyclone overflow at a specific gravity of 1. 25 (i.e. 32% solids) is transferred by gravity to two revolving chip screens for wood chip removal and from there to a pump box. Two 5 x 5 SRL pumps feed the pulp to the thickeners. The underflow from the cyclones is fed to two 8 x 8 Allis Chalmers ball mills which discharge to the common mill discharge pump box. Thus, a closed circuit is formed between the ball mills and their respective bank of cyclones. The circulating load as most recently calculated is 262%."

Jan 1, 1966

By J. Chao, C. Tan, N. Stubina

"Since J978, Falconbridge Limited has operated two electric furnaces at its nickel-copper smelter in Sudbury. As part of its S02 Abatement Program, the smelter has undergone many changes over the last seven years.This paper describes the impact of these changes on the operation of the furnaces. Some of the topics to be covered include: the installation of sidewall copper coolers; current operating conditions; and furnace heat and mass balances. HistoricalFalconbridge began smelting ores in the Sudbury area in 1930. The original smelter consisted of a 1.3 m by 3 m blast furnace and two 4 m by 6 m converters. The blast furnace was supplied with untreated mine are and molten slag/matte was discharged into a round settler.In 1933 the smelter began treating flotation concentrates. The concentrates were mixed with fine magnetic ore and flue dust, then sintered on down-draught Dwight Lloyd machines. This provided an agglomerate suitable for furnace burden which was charged to the blast furnace while still hot.Between 1930 and 1954 nickel production was increased by lengthening the 3 m furnace to 4.6 m, then to 6 m, and later by constructing additional furnaces. By 1958, the plant consisted of one 7.5 m blast furnace, a settler, and three 4 m by 9 m converters."

Jan 1, 1994

By Minoru Fujita, Ian M. Johnson

"A helicopter-borne geophysical survey was flown in 1978 over selected areas on Kyushu Island, Japan. The principal sensors were a moving source electro-magnetic system and a magnetometer. Maps of apparent resistivity were generated from the EM data. Based on the resistivity signature of known deposits within the survey areas, targets were selected for ground follow-up. Drilling of one such target in late 1980 resulted in the discovery of a gold deposit from which full production will begin in the summer of 1985. The deposit contains a minimum 120 tonnes (3.86 million ounces) of recoverable gold and is the largest in Japanese history. The deposit is in a geological setting previously unsuspected of hosting precious metal deposits. The case history suggests a preferred exploration strategy which might be employed in other similar geological environments.IntroductionThe Hishikari area is located some forty-five kilometres north of Kagoshima city, Kagoshima Prefecture, Kyushu Island, Japan (Fig. I). The area and its environs is one with a number of gold deposits which have been worked with varying results since the late 1800s. The large st deposit in terms of recovered gold is the Ohkuchi (or Oguchi) Mine (Fig . 2) which was recently closed due to exhaustion of reserves. The Ohkuchi Mine started production in 1896. A total of 22.2 tonnes (714 ,000 ounces) of gold, with an average ore grade of 13.6 grams/tonne (0.39 ounces/ton), was extracted over the Life of the mine.In an attempt to discover new deposits , the Metal Mining Agency of Japan (MMAJ) carried out a regional geologic mapping program of the area between 1975 and 1977. This was followed by a helicopter-borne electromagnetic and magnetic survey. The airborne survey was flown by Scintrex and the compiled results presented to MMAJ in early 1979."

Jan 1, 1985

By G. M. Brownell

Introduction The Flin Flon mine is located on the boundary line between the provinces of Manitoba and Saskatchewan at a point about four hundred miles northwest of Winnipeg. A branch of the Canadian National railway provides the town of Flin Flon with direct transportation facilities. The property was staked in 1914 and, after a considerable amount of exploration; the Hudson Bay Mining & Smelting Company was organized and brought the property into production in November, 1930 (1). Mining is carried on by open pit and underground methods at the rate of about 4,400 tons per day. Production for the year 1934 was: 99,334 ounces of gold; 1,335,319 ounces of silver; 37,486,054~pounds of copper; and 49,427,280 pounds of zinc; in addition to small amounts of cadmium and selenium. The Flin Flon deposit is one of the largest low-grade ore deposits in Canada with complete hydro-electric and metallurgical plants for the production of blister copper and electrolytic zinc. Previous Work The development of the Flin Flon mine into one of the major mining operations in Canada has created a need for a more detailed geological study of the area. Practically all of the information published to date concerns the general surface features. It is the purpose of this paper to deal more specifically with the ore-body and its relationship to the enclosing rock as revealed by studies made possible through recent underground development. The earliest published report on the area is by E. L. Bruce (2), who made a reconnaissance geological investigation of the region for the Geo-logical Survey of Canada in 1914 and established the main. petrological units. Several years later the area immediately around Flm Flon was mapped in greater detail by F. J. Alcock (3). In the summer of 1934, the area of Missi sediments to the north and east of the mine was studied by J. W. Ambrose. His report has not yet appeared in print but his findings are of importance.

Jan 1, 1935

By L. Xia, B. Hart, K. Douglas

In the flotation of Rare Earth Element (REE) bearing minerals, oxalic acid is reportedly acting both as a depressant and pH modifier. Testing has established the significance of oxalic acid in the flotation process however its specific role in either the recovery or selectivity of REE over their gangue minerals is not well understood. Pulp pH reduction trials with alternative acids have not shown the same effect on the REE mineral recovery or the depression of gangue phases. This work examines the effect of oxalic acid on the surface of gangue minerals (quartz and carbonates (dolomite and calcite)) in a series of conditioning tests. Gangue surface analyses by TOF-SIMS indicate that oxalic acid inhibits the transfer of secondary ions generated during the conditioning process from one mineral phase to another. In this regard, the oxalate anion acts to fix ions in solution through chelation, limiting their participation in surface adsorption.

Jan 1, 2014

By T. H. Etsell, P. C. Holloway

Vanadium is concentrated in the fly ash which is produced as a solid waste from oil sands operations in northern Alberta. Although a process flowsheet using sodium chloride as a roasting reagent has been developed at the University of Alberta, recent studies examine the p otential o f p otassium o r c alcium s alts a s alternative reagents for roasting Suncor fly ash to recover vanadium. Suncor fly ash was roasted with CaO, Ca(OH)2, CaCO3, CaSO4.2H2O and KC1 at 750, 850 and 950°C. Water leach extractions for the calcium compounds were low (<45%); leaching with 100 g/L Na2CO3 gave maximum extractions of 56 to 69% at 950°C. Ash roasted with KCI behaved similarly to ash roasted with NaCl. These tests indicate that similar roasting conditions (25 to 30% KCI, 850°C, and 2 to 4h) could be used to achieve similar water leach extractions (75 to 85%). However, the lower solubility of KVO3 in solution, compared to NaVO3, would make the use of KCI instead of NaCl less attractive from a process and economic standpoint. Mineralogically, leucite (KAlSi3O8) was the predominant phase in ash roasted with KCl while, in crystalline samples of ash roasted with calcium compounds, anorthite (CaAl2Si2O8) and pseudobrookite (Fe2TiO5) were identified. Ash roasted below 950°C with the calcium compounds remained poorly crystalline.

Jan 1, 2004

By C. Sideco

"Concentrate drying at the Sullivan Concentrator goes back to 1937 when the original coal-fired dryer was put into operation. This was a second hand 8' dia. x 56' long Struthers-Wells rotary dryer that came from the phosphate plant in Warfield, B.C.In 1962, replacement of the old dryer was seriously considered. The shell and the auxiliary drive mechanism were badly worn and needed replacing. In April 1963, the new 8' dia. x 65' long fuel oil-fired Struthers-Wells dryer went in operation at an installed cost of $174,000.In 1965, it was apparent that a major rebuilding of the dust collecting system would have to be done. A study was carried out and a Ducon Dynamic Gas Scrubber was installed. The system went in operation in November 1966 and has fully met expectations.In the same year, the zinc dryer was converted from fuel oil to natural gas. The conversion has resulted in savings in fuel cost of 12 to 15%.Frame No. 1Zinc Dryer PerformanceDryer Make - Struthers-WellsDryer Size 3/4 8' dia. x 65' long Drum Drive - 100 HPSpeed of Rotation - 5 RPMFeed Rate - 50-65 TPHFeed Moisture - 10-12%Discharge Moisture - 4-6%Dryer Inlet Temperature - 1600-1800°F Dryer Outlet Temperature - 200-250°F Stack Gas Volume - 25,000-40,000 CFNDust Collecting Efficiency - 99.75-99.98% Duet Loss in Stack - 50-300 lbs./day"

Jan 1, 1972

By M. G. Goudge

IT IS ENOOURAGING indeed to note during the past year that, despite a slackening off in many markets and with numerous major difficulties and problems to solve, the mining industry of Nova Scotia was maintained at a very high level. The value of the Province&apos;s mineral production for 1957 amounted to approximately $65,000,000. This represents a drop of only 1.5 per cent from the figure of the previous year. Coal Atlantic Collieries, Ltd., opened a new coal mine during the year at Bras d&apos;Or. This colliery is equipped with the most modern type of mechanical equipment available, with transport of the ?coal by a belt-conveyor system. Other mines in the Province continued to mechanize their operations by the addition of Diesel haulage locomotives and other mechanized mining equipment. New wash plants are in operation and .an additional one is planned.

Jan 1, 1958

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