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By David A. Orava, Richard C. Swider

"The technical knowledge and practical experience accumulated by industry and others in abating acid mine drainage (AMD) is being proactively applied at every phase of the mine life cycle. This paper traces the mine life cycle from exploration to post closure monitoring and maintenance, and reviews AMD abatement measures that have become an integral component of exploration and mining activities.Attention is increasingly being given to evaluating AMD potential as part of exploration work, and studies related to project feasibility and design. Mining, mineral processing, and waste management options are selected taking into consideration their suitability to inhibit AMD. These inhibition measures are typically committed to in closure plans submit-ted at the permitting stage. Mines are operated and decommissioned, often progressively, as planned and in accordance with environ-mental protection policies."

Jan 1, 1996

By K. Kim

"All milling operations would like to achieve the best possible recovery in combination with the highest achievable throughput. Unfortunately, many operations have problems with low recovery, low throughput or both. In the majority of these cases investigated by the author, the solutions to improve recovery and throughput were simple. The solutions did not include implementation of new technology or major capital, but rather a return to fundamentals. In most cases, problems occurred because the operation was not following their own operating procedures, because the design of the circuit was changed without adequate change management or understanding of the implications of changes, or because basic metallurgical measurements and control were not taken or ignored. In this paper, examples of these problems and their solutions derived from long and varied experience will be discussed. The objective of this presentation is to provide the milling operator with practical and readily implementable solutions to common milling issues to improve throughput and recovery.INTRODUCTION Mill operations can be evaluated by many operating parameters, but the two best indicators are recovery and throughput. These two parameters summarize the wellbeing of an operation. The grade to the mill is also a good indicator, but this is usually controlled by the mine. The best recovery and throughput are achieved through a team work involving operators, maintenance workers and metallurgical staff. The milling operations include many unit operations, such as crushing, grinding, flotation, leaching, carbon in leach, Merrill Crowe, roaster, autoclave and refinery. The tools available to the operations are plant design, process measurements, assays, metallurgical balance, and operating strategy. Twelve real life examples of improvements of recovery and throughput are presented in this paper. EXAMPLE 1: CRUSHING CIRCUIT WITHOUT FINE ORE BIN At this operation plant throughput could not be maintained at a high rate because feed to the mill became coarse during the day. The cone crusher was feeding the ball mill directly. As the day wore on, the gap on the cone crusher would slowly increase, which would cause the product size to increase. This would increase the re-circulating load on the ball mill. The throughput would decrease accordingly. Furthermore, the throughput would decrease more with high frequency of maintenance on the cone crusher."

Jan 1, 2019

By Roger T. Laine

"The Carswell structure, located in the western part of the Athabasca Basin, northern Saskatchewan, has been extensively explored since 1967. This exploration has been successful and lead to the discovery, in 1970, of the D sandstone-hosted unconformity related deposit. By the end of 1984, five additional basement-hosted unconformity related deposits had been delineated: the OP and N discovered in 1970, the Claude in 1971, the Dominique-Peter in 1981, and the Dominique-Janine in 1984. The D deposit has been mined out; the Claude open-pit has already produced more than 500 tonnes of uranium, the development of the Dominique-Peter underground mine (first phase) has been completed, and production from the latter started in 1985.All six deposits are located in the southern part of the Aphebian metamorphic core, 18 km in diameter, which has intruded at least 1250 metres of Helikian Athabasca Group sediments during a cryptoexplosion event at 480 Ma, unrelated to the emplacement of uranium mineralization. The metamorphic rocks, affected by the Hudsonian Orogeny, are divided in two lithostratrigraphic units: the Peter River gneiss, aluminous gneiss series, and the Earl River complex, mixed quartzofeldspathic and mafic gneiss series. A well developed regolith profile is recognizable in the south along the contact with the sandstone and inside the metamorphic core sometimes associated with conformable sandstone beds.Basement and sandstone-hosted uranium deposits show many similarities:-linkage to unconformity;-mineralogy and geochronology with a first phase mineralization characterized by a polymetallic sulphide-uraninite-brannerite assemblage dated at 1150 to 1050 Ma, a second phase characterized by a simple sulphide-uraninite assemblage dated at 890 to 820 Ma, and a third phase characterized by a pitchblende-hematite dated at 380 Ma; and,-linkage to early Hudsonian structures with remobilization of these structures during intense hydrothermal alteration resulting in Mg chlorite-illite halos."

Jan 1, 1986

By K. Loutet, A. Guenkel, K. Nikolaisen

"The INCO SO2/air process was patented by INCO in 1985. Well over 80 mining operations worldwide are using this process to oxidize cyanides to cyanates in the tailings from gold, silver and copper mining operations. The sulphur dioxide (SO2) for this process can be supplied either as liquid SO2, SO2 gas or as a sulphite-based salt. The majority of SO2/air operations have used sulphite-based salts as the ‘SO2’ equivalent probably due to low capital cost. Liquid SO2 has also been used frequently, but due to concerns with safety and availability, this option is often not preferred. The solid salt sodium meta-bisulphite (SMBS) is commonly employed, but its cost is an order of magnitude higher than that of sulphur. Due to the high cost of SMBS, the increased capital cost for a sulphur-burning SO2 gas plant (green field or retrofit) usually has a pay-back of less than three years. In addition, a SO2 gas plant offers potential for significant heat recovery from the sulphur burning process. In terms of safety, the SO2 gas plant only requires the storage of relatively benign sulphur and the site inventory of SO2 will be limited to the plant gas volume. Therefore, a SO2 gas plant will not trigger the Canadian Environmental Protection Act (CEPA) E2 Regulations or the US Clean Air Act Section 112(r) accident prevention regulations, as may be the case for liquid SO2.Most existing mining operations using ‘SO2’ are gold operations, but in recent years there has been an increased interest in larger sulphur dioxide gas plants for hydrometallurgical facilities that employ leaching of cobalt/manganese minerals or precipitation of manganese/iron (e.g. Tenke Fungurume and El Boleo).This paper focuses on the production of sulphur dioxide gas generated on site and on demand for the use in hydrometallurgical processes. The capital and operational costs of a SO2 gas plant is compared to conventional process alternatives using sulphite-based salts or liquid SO2."

Jan 1, 2016

By K. Prajapati, P. Hes

Transmission of vibration to the operator from percussive vibrating tools is increasingly of concern in industrial and mining applications. Prolonged exposure to high levels of vibration transmitted via the hand causes disorders known as hand-arm vibration syndrome (HAVS). The vascular component of HAVS is called vibration white finger (VWF) and has a debilitating effect on the hand. Vibration at frequencies below 1250 Hz, a tight hand-grip force and cold environments are reported to increase the likelihood of developing VWF. A vibration damping handle design with patents pending that addresses some of the causes of VWF has been developed and retrofits onto jackleg pneumatic rock drills. The handle is decoupled from the drill while maintaining jackleg twist-grip controls on the hand-grip using a combination of sealed self adjusting hydraulic pistons and compliant materials in series, and a new air control valve. The ergonomics of the hand-grip was also modified by the addition of a polyurethane sleeve with a diameter of 50 mm. The new hand-grip reduces direct cold metal contact and minimizes grip force. Measurement of vibration as the quantity acceleration was made in accordance with international standard ISO 5349. Overall vibration damping in all axes of 50% to 63% was attained at frequencies below 1250 Hz. The dimensions of the damping handle are comparable and its weight is only 100 g heavier than a standard handle.

Jan 1, 2001

By Michael S. Moats, Prashant Bagri

"In recent years with increasing concerns about energy consumption in hydrometallurgical processing, there is an ongoing attempt to use Catalytic Titanium Anodes (CTAs) for copper electrowinning. For this work, anodes with IrO2 - Ta2O5 coatings were prepared in the laboratory with the same total coating loading but varying the number of layers by changing the speed of withdrawal in dip coating. A second set of CTAs were fabricated on niobium, Ti Grade 1, Ti Grade 7 and Ti Grade 36 metal substrates. All the anodes prepared in the laboratory were characterized using standard electrochemical techniques and subjected to accelerated life testing. It was found that the coating would not adhere to the niobium substrate, the grade of titanium had a minimal to no effect on the life of the anode, and it is observed that as the coating speed slows, there is an increase in the electrochemically active surface area of the coating which seems to directly contribute to an increase in the Tafel slope of the anodes. There was inconclusive evidence on the effect of coating speed on anode lifetime.INTRODUCTIONLarge scale hydrometallurgical extraction of copper has become widely practiced over the last 40+ years. The hydrometallurgical route entails leaching, solvent extraction and electrowinning. With the increasing desire to process refractory sulphides like enargite and chalcopyrite through the hydrometallurgical route, use of hydro-processing of copper is expected to remain high.In conventional electrowinning, copper is deposited on the cathode and an inert anode is used for oxygen evolution. Presently, the most common anode material is rolled lead-calcium-tin and the cathode is 316L stainless steel (Robinson et al., 2013). This lead alloy is fairly inexpensive and is robust, providing lifetimes typically of 4+ years. The main drawbacks of lead alloys are their relatively high oxygen evolution overpotential, the need for cobalt in the electrolyte to reduce their corrosion, the contamination of cathode product by lead, and the generation of harzardous by-products (Hiskey, 1999)."

Jan 1, 2016

By T. Kerr, C. Mattich, J. Wilson

"In refractory gold concentrates, gold is occluded in sulphide minerals preventing efficient cyanide leaching. Hence, roasting is used to oxidize sulphur and organic carbon, the latter being necessary to minimize recovery loss through the preg-robbing effect. In 2009, Outotec commissioned the circulating fluidized bed roaster at Syama gold mine in Mali. Since 2013 Resolute and Outotec have been implementing improvements to the roaster performance with the capacity increasing from 8000 t/month in 2013 to above 13,000 t/month in 2016, while achieving a residual sulphide sulphur and organic carbon contents of below 0.1 wt.% and 0.4 wt.%, respectively. Thus a gold recovery in the CIL of above 90% is attained. In 2016, Outotec audited the Syama roaster. The analysis resulted in the Low Carbon Roaster (LCR) upgrade concept which (i) allows re-processing of calcine dust from the spray cooler and ESP after pelletization and (ii) allows the roasting of a further fine-organic carbon rich feed, i.e. de-slime circuit tailings. The LCR upgrade aims to reduce organic carbon to <0.2 wt.% and increase roaster-leaching gold recovery by >3%. Project development included extensive testwork. The LCR process is expected to become operational during FY 2019.INTRODUCTION Double refractory sulphide ores exhibit the characteristics of gold locked within pyrite grains, in the presence of preg-robbing natural (organic) carbon. Hence, to achieve high recovery during subsequent processing steps, i.e. cyanide leaching, oxidation of sulphide sulphur is required, producing a porous calcine by way of a roasting step. This allows for the gold contained within the pyrite grains to be accessible during cyanide leaching. Furthermore, it is necessary to oxidize the organic carbon. Oxidizing the organic carbon is essential as gold recovery loss occurs as a result of gold-cyanide complexes being adsorbed on organic carbon, this phenomenon is termed as preg-robbing (Miller et al., 2016). The gold absorbed on the organic carbon is lost, reporting to the tailings stream. Hence, the aforementioned oxidation of sulphide sulphur and organic carbon is the process goal. Nonetheless, the latter must occur at a controlled temperature which is concentrate/ ore specific, since the pores of the produced calcine should not sinter, as this makes the gold contained in the calcine less accessible during leaching, leading to gold recovery loss. The tight temperature control requirement is a decisive factor in the choice of a Circulating Fluidized Bed (CFB) as the roasting reactor, due to the excellent mixing characteristics of the CFB which results in temperature homogeneity of (+/-10°C). Roasting of double refractory ores, as described above, can be included in the flowsheet after comminution and grinding, a process termed as whole ore roasting, or by including a flotation circuit termed as concentrate roasting. Roasting the flotation concentrate results in less solid flow, increased sulphide sulphur grade and organic carbon content resulting in a higher heating value and higher gold content. A typical composition of the Syama ore and concentrate is given in Table 1. Ore average values presented correspond to the period 2015, while concentrate values are typical for the flotation performance throughout the period 2012–2015."

Jan 1, 2017

By Sylvie Lévesque, Cory Hennessey, Daniel Amariei

"In the iron ore industry, fine particles recovery is an important concern in terms of process performance and production costs. Continuous efforts are thus devoted to increase the efficiency in handling these fines.The Reflux Classifier (RC) is a relatively new technology that is mainly used in the coal and industrial minerals industries. The operating principle of this system is based on three mechanisms: hindered settling, autogenous dense medium and lamella settling. A preliminary evaluation of the Reflux Classifier technology for the beneficiation of iron ore fines was formerly done at the pilot scale using a RCTM300 unit. The good results obtained, using iron ore fines from screened spiral stream, made this technology very attractive for the iron industry. However, the high capacity of the RCTM300 unit (1–3 t/h), makes it unsuitable for R&D purposes. Thus, a smaller unit, the RCTM100, was assessed to validate the performances obtained with the RCTM300.This paper summarizes the performances obtained with the RCTM100. The challenges of the scale-down related to the adaptability of this technology to the iron ore industry are also presented. The results are compared to the RCTM300 performances, as well as benchmarked against sink-float tests. The metallurgical results on feed and products issued after the test work with the RCTM100 unit are supported by mineralogical characterization using a Mineral Liberation Analyzer.INTRODUCTIONFine particles recovery by physical separation means is a historical concern (Holland-Batt, 1992; Peukert and Wadenpohl, 2001; Srivastavaa et al., 2001; Majumder et al., 2003). Attempts to improve fine particle recovery at the laboratory, pilot and industrial scales adopting different strategies with traditional equipment or assessing new promising devices such as the MGS (multi-gravity separator), the Kelsey jig, the Yang jig, etc. (Kim, 2002; Goudreau, 2008; Kerr, 2012) have yielded variable success."

Jan 1, 2016

By E. W. Coderre, R. C. Baxter

"This paper describes the townsite of Wabush and the two railways operated by Wabush Mines for the loading and unloading of iron ore concentrate. The town of Wabush is located approximately 200 air miles north of Sept-Iles, Quebec and is in the Province of Newfoundland and Labrador. Construction of the town-site began in 1961 to provide housing accommodation for the construction force and permanent employees in the mining and milling operations located 4 miles away. Wabush Mines operates two short railway lines in loading and unloading concentrate between the concentrator, located at Wabush, and the pellet plant at Pointe Noire, Quebec. Both of these railways connect with the main line of the Quebec North Shore and Labrador Railway and provide a shuttle service between the two phases of the operation."

Jan 1, 1969

By R. N. Chakravorty

Environmental monitoring plays a key role in coal mine safety. In recent years, significant advances have been made in the development of systems suitable for monitoring air in underground coal mines. Because of intensive mining and large capital outlay, the need for higher productivity consistent with safety is well recognized and it appears that environmental monitoring may help achieve this objective. This paper reviews the state-of- the-art in the monitoring technology with particular reference to hazardous gas detection in underground coal mines. The preliminary results obtained from ongoing studies, with regard to continuous monitoring of methane and carbon monoxide in mine air in some of the operations in Western Canada, are discussed. The inadequacies of the methods using spot samples are examined and the need to supplement the present practice with continuous monitoring systems is emphasized.

Jan 1, 1979

By S. Goodman

Successful exploration for and exploitation of a mineral deposit requires an accurate understanding of the deposit architecture in 3D, and of the development of the mineralizing system through time, which requires a thorough comprehension of the structural framework of the deposit. The integration of geological, geophysical and geochemical datasets to arrive at a 4D structural framework is well-established and has been successfully applied by SRK Consulting in projects from deposit to regional scale. In some cases, we can go beyond this, applying the SEEBASETM technique, which utilizes a ?bottom-up? approach to basin analysis. SRK?s approach primarily relies on the interpretation of magnetic and gravity data, calibrated with many other datasets including mapped geology, topography, event histories, wells/drillholes and seismic data. The SEEBASETM model is a culmination of this data integration and is produced through an iterative process of structural interpretation and geophysical modeling, where an interpretation of basement composition and 4D structure is used to constrain depth-to-basement geophysical modeling, and the modeled depths are then used in conjunction with the structural interpretation to constrain contouring of the basement topography. The result is a rigorously calibrated, 3D view of the basement surface, which can be used to understand the basement and basin architecture, and thus serves as a predictive exploration model. This technique, which was developed for use in the petroleum industry, is now finding success as a predictive tool in mineral exploration.

May 1, 2003

By D. K. Sarkar, J. Perron, J. D. Brassard

"Nearly perfect spherical shaped water drops rolling-off from the surface of lotus leaf is one of the beauties of nature. This kind of surface is called superhydrophobic, since the water does not like it. Physically, a superhydrophobic surface provides a contact angle (CA) of water over 150°. The combinations of both mico-nanostructure topography as well as low surface energy are essential to have such high CA on a surface. Nano-micro structured superhydrophobic surfaces have been developed in different methods. (i) Monodispersed fluorinated silica nanoparticles have been synthetized via Stöber Sol-Gel process and deposited on various surfaces, such as aluminium or glass, to obtain transparent superhydrophobic thin films. (ii) Similarly, zinc stearate nanocomposite coating has been fabricated by spray process on the same substrates. These thin films are found mechanically robust with drag reduction of coefficient 16% lower than as-received surfaces. (iii) By electrodepositing pure zinc on steel surfaces and further coating it with diluted room-temperature vulcanized silicone rubber, the surface become superhydrophobic. This superhydrophobic surface protects the steel against corrosion by increasing the polarization resistance from 1.5 k? on steel to 44.4 k?. This coating also reduced the ice adhesion on the steel surface 6.3 times as compared to bare steel substrates. Globally, these superhydrophobic surfaces have tremendous applications against corrosion reductions, drag reductions and ice adhesion reductions.INTRODUCTIONSuperhydrophobic coatings are increasingly attractive to the industry and academia due to their unique self-cleaning properties as a result of their water repelling characteristics. Fabrication of superhydrophobic coating is an inspiration from nature as water is seen to repel on many natural surfaces such as those of the lotus leaves, butterfly wings, water striders’ legs, and so on (Gao & Jiang, 2004; J. Huang, Wang & Wang, 2006; Neinhuis & Barthlott, 1997; Zheng, Gao & Jiang, 2007). This non-wetting phenomenon is well understood on lotus leaves, shown on the Figure 1 (a), and it is considered as the basis of the studies of superhydrophobicity. The existence of this binary structure on the surface of the lotus leaves allows a large amount of air entrapment and consequently reduces the contact area of water on it and the presence of low surface energy waxy components with reduced affinity to water together leads to the superhydrophobic properties. The phenomenon is shown on Figure 1 (b). Cassie and Baxter (Cassie & Baxter, 1944) as well as Wenzel (Wenzel, 1936) proposed two mathematical models to explain the wetting phenomena on rough surfaces that leads to superhydrophobic properties. By definition, superhydrophobic surfaces are characterized by a water contact angle value = 150° with the rolling off of water drops from the surfaces (Sarkar & Saleema, 2010). Superhydrophobic surfaces find tremendous importance in the technological world where it can applied in domains such as anti-corrosion, anti-biofouling, electrowetting, icephobic and even in drag reductions (Bushnell & Moore, 1991; Cao, Jones, Sikka, Wu & Gao, 2009; Carlborg & van der Wijngaart, 2010; Carré & Mittal, 2009; Y. Huang, Sarkar & Chen, 2010a; R. Karmouch, Coude, Abel & Ross, 2009). However, the most important challenge faced by industries is their feasibility large scale in an effective an economical manner."

Jan 1, 2016

By E. Onal, C. Craddock, A. Chapman, M. R. Endsley

ABSTRACT Mining equipment operators must interpret and respond to complex information delivered by technology-centric rather than user-centric systems. The ability to achieve high situation awareness (SA) in the face of this data overload is a key challenge to effective decision-making and information exploitation. Incidents attributed to human error that compromise safety and result in loss of revenue, or even life, are often the result of system designs that overload human cognitive capabilities. This paper defines SA as it relates to the operation of mining equipment and describes the design and preliminary evaluation of a new electric shovel operator user interfa

Jan 1, 2013

By L. C. Stevens

The particular purpose of this paper is to direct attention to the development of underground conveying as applied to methods of working coal in the mines of Alberta. Historical A retrospective view of coal mining discloses a continuous effort, on the part of those interested, to substitute mechanical contrivances for hand labour. A patent for a coal-cutting machine was granted to Michael Menzies in 1761, at which time much of the transportation of coal underground was accomplished by means of sledges. Early forms of cutting machines attempted to duplicate the action of a miner&apos;s pick, and one hundred years lacer than Menzies? patent we still find this class of machine, driven by water power or compressed air, in use to a limited extent. A coal-cutter using the principle of a circular saw and worked by hand was exhibited in London in 1851, and from these crude beginnings the machines of today have been evolved. Transportation of coal underground has similarly been subject to considerable improvement. The above mentioned Michael Menzies took out a patent in 1750 covering the use of a self-acting incline plane, which is probably the earliest record of any system devised to lighten the load of the crammer or car-pusher of those days. In the year 1868 the Gillot & Copley machine was patented, this being a compressed-air-driven disc coal-cutter which proved highly successful. The chain cutters were a natural development from this type, and for a number of reasons they have been even more successful in the majority of cases.

Jan 1, 1930

By B. A. Monkman

"IntroductionONE OF :THE most effective methods by which the construction industry is combatting mounting building costs is by making increased use of lightweight materials, thus reducing the dead load to be carried •by structures. This applies to non-metallic materials as well as to metallic ones, and particular attention has been given to developing lightweight aggregates for use in concrete.The use of lightweight aggregates is not new and, in fact, dates back to the Roman Empire, when pumice was used in the walls and domes of the Roman buildings. More recently, and up to a decade or so ago, the demand for these aggregates was met from deposits of volcanic cinders, pumice, scoria, etc., and from the by-products of blast furnaces and coal burning boilers. However, these sources of supply are no longer sufficient to meet the demand, for transportation costs pretty well restrict the use of the natural lightweight aggregates to the western cordillera regions where the deposits of these materials occur, and the use of expanded slag aggregates to the areas neighbouring the plants where slags are produced. As for cinders, the supply has been greatly reduced by the conversion of industry to fuel oil, natural gas, and powdered coal, and the large stockpiles which existed previously have been pretty well exhausted.Industry's approach to the problem of a decreasing supply, in the face of an increasing demand, has been characteristically direct. The solution has been to construct plants whose sole .purpose is to produce economically an acceptable light-weight aggregate from materials close at hand."

Jan 1, 1955

By J. S. Fox

"Pyroclastic rocks are useful guides to volcanic centers due to the tendency of their fragments to increase in size and volume toward the source vent. The felsic rocks of these centers can be the prime hosts of base metal deposits in the Precambrian Shield; their sub-volcanic equivalents are often the focus of porphyry copper mineralization in the Cordillera. Quantitative mapping of pyroclastic rocks has not yet developed into a routine prospecting tool in Canada, however, possibly due to the cumbersome nature of existing manual techniques and their limitation to structurally simple terrains.A rapid pyroclastic mapping method has been developed whereby the field geologist acquires only a down-plunge outcrop photograph, a record of the fragmental deformation ellipsoid and a record of some descriptive features from each station. Mean fragment size and volume percent are obtained later in the laboratory from a photo-enlargement: by means of a digital analyzer. A computer program uses the strain parameters to 'undeform' the field measurements and obtains genetic information from the descriptive data. Results can be superimposed on a geologic map, with values for each station being represented by a dot of a specified diameter corresponding to the size or volume percentile range to which the value belongs.Control traverses were run over the pyroclastic rocks surrounding the Anderson Lake mine and the Flin Flon South main shaft in northern Manitoba. In both locations, the mapping has delineated regular increasing trends in mean size and volume per cent toward the head frame."

Jan 1, 1977

"8.1. IntroductionThe stoichiometry of most named platinum-group minerals (POM) is known (cf. Cabri, 1981b, in Chapter 7), but, because these minerals are subject to a wide range of element substitutions, representative analyses require treatment in a separate chapter (section 8.2). The analyses, in all cases done by electron microprobe, are grouped in sections according to the principal platinum-group element (POE) for each POM, and then follow sequentially with increasing amounts of the principal POE starting with the ideal composition, when known. In order to facilitate reference to specific POM by name, an alphabetical listing is also given (Table 8.1). A range of compositions, in addition to one or several ""representative"" analyses, is given for some POM when more than one analysis has been reported for a particular locality. The tables of POM analyses (Tables 8.2 to 8. 76) include at least one analysis for every locality for which data have been published, to the best of the authors' knowledge. All analyses are referenced for locality and publication source, and include several unpublished analyses (all but one done at CANMET). Most analyses have been rounded off to one decimal place for amounts more than one per cent and their formulae calculated on the basis of an even number of total atoms. In all tables, ''n.d.'' stands for elements sought for but not detected and a dash signifies elements not sought, or when these haven't been specificed in the publication source.Section 8.3 contains tabulated analyses and, in some cases, also includes a critical assessment of POE-bearing minerals in which the POE occur in trace or minor quantities. The organization of the data in this section is by mineral groups; e.g., sulphides, sulpharsenides, silicates, etc. Some of these data are also discussed in Chapter 4 by Crocket (1981) and are discussed briefly in Chapter 6 by Crocket and Cabri (1981)."

Jan 1, 1979

By D. Verhulst

The Altair process digests ilmenite concentrate in high-chloride HC1 solution, with complete dissolution of titanium and iron. The Fe(III) ions are reduced to the ferrous form, and the solution is cooled to produce crystalline ferrous chloride. Titanium is transferred by solvent extraction into a purified, concentrated Ti stream, which is spray-hydrolyzed to produce TiO2 hydrate. The hydrate is further calcined with additives to generate a high-quality pigment. All the chloride streams are recycled. In the original flowsheet, the iron chloride is pyrohydrolyzed by spray roasting to regenerate 18% HCl, which is subsequently converted to HC1 gas and water by pressure-swing distillation. A modified flowsheet includes an alternative to iron chloride spray roasting, producing more concentrated HCl and decreasing the amount of solution to be distilled. Improvements in digestion, solvent extraction and final pigment production are also introduced. A 100 t/y pilot plant is being built and will test the new concepts and confirm the overall water, acid and impurity balances of the process.

Jan 1, 2006

By W C. Shakespeare

The Ontario Committee on Taxation is making a comprehensive study of taxation in the Province of Ontario, and in this connection has received representations concerning mining taxation from a number of interested parties. Some of the more important recommendations on mining taxation are reviewed in this article. Introduction FOLLOWING the appointment of the Federal Royal Commission on Taxation, the Ontario Government, effective in November, 1962, appointed the Ontario Committee on Taxation to review taxes and revenues available to the Province of Ontario and its local governments, to co-operate with the Royal Commission on Taxation and with any other bodies of enquiry appointed by other provincial governments, and to make such recommendations as it sees fit to the Prime Minister of Ontario and the Executive Council. The members of the Committee are: MR. L. J. SMITH, F.C.A., Toronto, (Chairman) MR. ERIC HARDY, Toronto DR. R. CRAIG MCIVOR, F.R.S.C., Hamilton MR. CARL A. POLLOCK, Kitchener MR. R. BREDIN STAPELLS, Q.C., and Toronto. Like its Federal counterpart, the Royal Commission on Taxation, the Ontario Committee has held public hearings, has received written

Jan 1, 1965

By John Tribe

"This paper gives the organizational history of Luscar Ltd. and its various coal producing operations. Each 0/ the operations is then described individually. They include the Bienfait Mine, the Boundary Dam Mine, the Diplomat Mine, the Luscar Mine and the Coal Valley Mine. The company&apos;s plans/or expansion are also discussed. IntroductionLuscar Ltd. is an Edmonton-based energy company formed in 1967 through an amalgamation of two pioneer coal companies-Mountain Park Collieries and Luscar Coals Ltd. In 1912, Mountain Park Collieries initiated the development of an underground mine in the Coal Branch area of Alberta. This mine necessitated the establishment of a townsite and the provision of rail access. The second operation, Luscar Coals Ltd., was established in 1921 at Luscar, Alberta. This was also an underground operation and required the development of a rail spur and townsite. The product from both mines was used to fuel railway steam locomotives until the 1950&apos;s. The market demand for coal decreased as the use of the diesel locomotive increased, so that these operations were finally closed in 1954. Through the amalgamation of the two companies in 1967, however, Luscar Ltd. was formed to become an active participant in the revival of coal operations. Western Canadian Luscar Ltd. is involved in the exploration, development, production and marketing of coal, coal products, oil and gas. Luscar Ltd. is currently participating in five producing mines (Fig. I). The Diplomat Mine, approximately 125 miles southeast of Edmonton, was in production when it was acquired in 1949 by Luscar Coals Ltd. In 1966, the Bienfait Mine and char plant were added. The Luscar Mine, which is a 50/50 joint venture of Luscar Ltd. and the Consolidation Coal Company of Canada, and is operated by Cardinal River Coals Limited, started production in 1969 on the original Luscar Coals Ltd. mine site. The Boundary Dam Mine was opened in 1974. Both the Bienfait and Boundary Dam operations are located in the lignite coal fields of southeastern Saskatchewan. The most recent addition to the group is the Coal Valley Mine, 40 miles southwest of Edson, Alberta. It commenced commercial production in July, 1978 under the operation of Luscar Stereo (1977) Limited."

Jan 1, 1980