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By A. Motamedi

Indoor localization has gained importance as it has the potential to improve various processes related to the lifecycle management of facilities and to deliver personalized and location-based services. Radio Frequency Identification (RFID) based systems, on the other hand, have been widely used in different applications in construction and maintenance. This paper investigates the usage of RFID technology for indoor localization of RFID equipped movable assets during the operation phase of facilities. The location-related data on RFID tags attached to fixed assets are extracted from a Building Information Model (BIM) and can provide context-aware information inside the building which can improve Facilities Management (FM) processes. The paper proposes a new approach to use received signals from available reference tags in the building attached to fixed assets to locate movable assets. The approach uses signal pattern matching and clustering algorithms for localization. As a result, a user equipped with an RFID reader is able to estimate the location of target assets, without having access to any Real- Time Location System (RTLS) infrastructure. A case study is performed to demonstrate the feasibility of proposed methods.

Aug 1, 2013

The topic of the relationships between energy and particle size has had two very active periods -the first in the early thirties, when the relative merits of Rittinger's and Kick's proposals were vigorously debated; the second in the early fifties, when Bond's Third Theory was published. This second stage has produced several contributions that have provided a clearer picture of energy /size correlations in comminution. Derivations of a general relationship have been made from single-fracture experiments and from the rate of comminution, and both methods arrive at an equation of the type E = AK-11? The constant A in the equation may be regarded as a grindability parameter. In some respects, an understanding of the phenomena associated with comminution is still lacking, and research in this field should therefore be expanded. T HE SEARCH for a relationship between the energy consumed in comminution and the size of the broken product has been long and varied, and many

Jan 1, 1964

By Victor Azbe

Azbe System of Controlled Calcination To obtain good and cheap lime there are certain fundamental requirements that need to be satisfied. These are : (1) Proper combustion of fuel and steady supply of heat to the kiln. (2) Proper heat distribution in the kiln. (3) Uniform drawing of lime through the several shaft sections. (4) Complete cooling of the lime and recovery of the heat. (5) Temperature control of the hot zone by economical means. (6) Ample draft to obtain high capacity. (7) Arrangements to facilitate operation. Figure 17 shows diagrammatically one of the smaller kilns, intended for large stone. Such a kiln can be supplied with gas from a centrally located automatic gas producer, or, as shown, from an integral producer located snugly against the kiln. These producers make very good gas and have a gasification capacity of either 10 or 15 tons of coal a day. The producers have water-sealed ash pits, a rather thick fuel bed that is conducive to the making of high-CO gas, and are under forced draft. No steam is used. Clinkering is prevented by admixing some spent gas from the kiln with the air. Coal feeding is from a coal bunker through spouts into the hoppers over the producer. This is done, at proper intervals, by manual operation of slides, but it is planned to install mechanical feeders. Central mechanical gas producers have the advantage of requiring little labour, but the blowing of soot is a problem, as also is the proper distribution of the gas among several kilns. In the case of integral gas producers, soot from the centre burner is blown back into the producer to be burned, and the supply of gas to the kiln is controlled by regulation of air to the producer. In large plants, the mechanical producer may be preferable, but in small ones, the integral producer is cheaper, better, and more reliable. The kiln shown in Figure 17 is suitable for both systems of gas supply. It will be noticed that there are no side gas burners. All gas enters the kiln through the centre burner in a manner that permits any desired amount of gas to be directed to any of the kiln sections by the aid of regulating slides.

Jan 1, 1946

By P. Favreau

"This paper describes the progress accomplished at the Noranda Technology Centre in the field of three-dimensional computer-aided underground blast design. Traditional methods of laying out underground blasts are reviewed, and the new computer-aided approach is described. Time savings achieved through the use of BLASTCAD can be advantageously used to better engineer blasts, using models and blast vibration analysis. Future work involving the attachment of blast models directly to the system is also addressed.IntroductionThe Noranda Technology Centre's (NTC) Environment and Mining Laboratory, in cooperation with the mining operations of the Noranda Group, is committed to the development and implementation of new technologies in the field of mineral extraction . Within the frame of its research program, the Blasting Technology Program is developing computer "" tools"" designed to assist the blasting engineer or technician. These computer "" tools"" are regrouped under a global software system called BLASTCAD.The BLASTCAD project started in 1990 at NTC. At that time computer programs designed to calculate and model various blasting parameters had been accumulated. These programs cam e from different sources and were mutually incompatible. Furthermore, they were developed as research programs with tittle effort spent on user interface. These programs are very useful, but are highly specialized, need large input files and can be quite tedious to use as ""standalone"" packages .Therefore, the situation being faced was one where all these programs were available at the Noranda Technology Centre, but not a t the operations. The two following options were then considered: 1. continue to run all the models and programs at the Noranda Technology Centre, and present results through reports to the mines, or2. regroup all the different programs under a single one that would make them share the same data base and be transported to the user. This second option is the one that was adopted; the result is BLASTCAD."

Jan 1, 1993

By D. C. Peck, James. R. S., Chubb. P. T.

"Abstract -The East Bull Lake gabbro-anorthosite intrusion is one of several Early Proterozoic layered matie intrusions occurring along the Southern Province - Superior Province boundary in the Elliot Lake - Sudbury region, Ontario. The base of the East Bull Lake intrusion comprises abundant plagioclase cumulates (Leucogabbronorite Zone) hosting two distinct styles of sulfide mineralization: (1) disseminated magmatic sulfides, and (2) disseminated to massive, structurally controlled sulfides. Both types of mineralization are enriched in Pd, Pt, Au, Cu and Ni. The host rocks to the sulfide mineralization display a range of interesting features including nodular textures, dendritic­ pegmatitic matie pods, inclusion-rich zones (pyroxenite, anorthosite and granitic inclusions) and mag­ matie breccias. Disseminated chalcopyrite, pyrrhotite and pentlandite occur in concentrations of up to lOOJo within erratically distributed gossan pods near the base of the intrusion. The sulfides were originally precipitated from intercumulus liquids, but were subsequently recrystallized and locally remobilized along fractures during the major period of metamorphism and deformation that af­ fected the East Bull Lake intrusion. The base- and precious-metal tenor of the structurally controlled sulfides can be explained by extensive remobilization and reconcentration of the pre-existing magmatic sulfides in the vicinity of a major shear zone. Both styles of sulfide mineralization locally contain ppm abundances of POE + Au and are generally Pd- and Cu-rich, although both display large variations in Pd :Pt and Cu:Ni ratios. The magmatic sulfides are more strongly enriched in POE and contain up to 1470 ppm Pd in 100% sulfide. Severa! factors, including source characteristics, magmatic processes (crustal assimilation, fractional crystallization) and post-magmatic inter­ action with hydrous fluid, have influenced the present distribution of POE, Cu and Ni in the East Bull Lake intrusion .The magmatic sulfide occurrences from the East Bull Lake intrusion compare favorably with marginal-type deposits from rift-related intrusions (Noril'sk-Talnakh region, Siberia; Duluth Com­ plex, U.S.A.) in terrns of their distribution, but are most similar to reef-type POE deposits with respect to their base- and precious-metal geochemistry. The combination of high POE tenors and large tonnages that is observed for the POE-Cu-Ni mineralization from the East Bull Lake intrusion suggests that a good potential exists for the presence of economie concentrations of Pd, Pt, Au, Cu and Ni in the intrusion. On a global scale, the East Bull Lake intrusion is part of a suite of Early Proterozoic plutons, many of which contain significant volumes of stratiform and/or marginal­ type POE-Cu-Ni mineralization. The East Bull Lake intrusion is also one of the oldest mineralized intrusions derived from a sub-Superior Province mantle source region that has given rise to several significant magmatic POE-Cu-Ni deposits during the period 2.5 Ga to 1.1 Ga."

Jan 1, 1993

ABSTRACT This paper details the work of RISKGATE, the largest Australian Coal Association Research Program (ACARP) occupational health and safety initiative to date. The program is an interactive online risk management system developed to maximize health and safety performance in the coal mining industry by implementing continuous improvement in managing major unwanted events. The comprehensive knowledge base covers tires, collisions, fires, isolation, strata control underground, ground control open cut, explosions, explosives, manual tasks, and slips/trips/falls. All major Australian coal mining companies contributed topic experts to this broad industry initiative: nine coal mining companies, more than 80 experts, and more than 400 days of individual time for knowledge-capture workshops.

Jan 1, 2014

By The Staff

THE gold mining industry in Canada is today the most important stabilizing influence in the country. This factor was brought out particularly during the 'depression' years, when steady employment was given to men in that industry and the monies spent in supplies and power in turn benefited the country to a great extent. At the same time, a commodity was produced which was saleable in any market of the world, thus maintaining Canada's credit in foreign markets and keeping her trade balances equalized. We have a vast area known as the Precambrian Shield. The agricultural possibilities of this area are practically negligible and it will depend entirely upon the mineral and forest resources to make this district an economic factor in the life of Canada. To date, from the mineral point of view, we have been highly successful. There are, however, still vast areas to be explored. It is tedious and laborious work, entailing great individual hard-ships and the expenditure of much energy and money. During my thirty years' experience in the search for, and operating of, gold mines, I have come to the conclusion that although individuals may give all their time, energy, and money, Governmental assistance is absolutely necessary in the development of hydro-electric power sites and roads. The Governments, to date, have given splendid co-operation along these lines, but in order that this great industry may go ahead they should continue their good work and, if possible, give greater relief from taxation to mines situated at a considerable distance from the railway.

Jan 1, 1938

By Greg Yuriy

Over the past two decades, Vale Canada has used discrete-event simulation in a key role to support many underground mining studies. Traditionally, general purpose simulation software was developed for manufacturing and service applications. Not until recently have Mine Designers and Simulation Specialists been able to model the dynamics of underground mining scenarios without extensive manipulation of the inherent tools and entities contained within these simulation environments. This paper discusses Vale Canada?s past experiences with a variety of simulation software, describing model development methods and highlighting some of the lessons learned. The paper concludes with a review of recently considered software and provides a framework of desired attributes/functions for modeling mining scenarios.

Aug 1, 2013

By A. Flemming

"As the next century draws near, new mine properties must be brought into production to replace existing operations that are approaching their economic life. This paper presents some of the critical technical issues being addressed by Manalta Coal Ltd. as they strive to bring the Telkwa Coal Project near Smithers, BC into production during the year 2000. The mine is planned to produce between 1.0 to 1.5 million tonnes per year of medium volatile coal for export to overseas thermal and PCI markets. IntroductionManalta Coal Ltd. (Manalta) is proposing the development and operation of a surface coal mine and associated infrastructure approximately six kilometres southwest of the village of Telkwa, British Columbia (Fig. 1). The infrastructure consists of a coal washing facility, tailings disposal area, clean coal haul road, access road and rail loadout facility. Over a 25-year period, the mine is expected to produce between 25 and 37 million clean tonnes of coal primarily for the export market.To achieve public and governmental approval for the development, the project will be reviewed under British Columbia’s Environmental Assessment Act. Manalta entered the formal Assessment process in February 1, 1997 with the submission of an Application for a Project Approval Certificate for the Telkwa Coal Project."

Jan 1, 1997

By John Stubbles

Data are presented on the global warming issue to reinforce the decision by the U.S to reject the Kyoto protocol. The evidence that CO2 is a problem rather than a benefit is inconclusive and will be discussed in this paper. Nevertheless, for economic reasons alone, the US steel industry will continue to minimize CO2 emissions (and the release of real pollutants) per ton of steel through energy reduction programs. However, relative to inevitable increases in absolute CO2 emissions from the utility industry and the transportation sector, future reductions by the steel industry will be inconsequential in the "big picture."

Jan 1, 2004

By O. G. Olvera

"Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Typical cyanide operations show poor performance and require oxidative pretreatments to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. This work focuses on evaluating the effect of the addition of a carbon resin as a sulfur collector on the oxidation of different arsenopyrite concentrates under atmospheric tank leaching (ATL) conditions. The addition of the resin improved the oxidation of sulfides and favored the formation of elemental sulfur over the generation of sulfate. The use of AF5 in ATL resulted in higher gold recoveries under standard cyanide carbon-in-leach and thiosulfate leaching.INTRODUCTION Refractory sulfidic ores consist of materials in which gold occurs finely disseminated within metallic sulfides or forming solid solutions, with pyrite and arsenopyrite being the two sulfides most commonly associated with gold. Gold is not readily accessible to solutions in these types of ores and typical cyanide operations show poor performance, thus making the use of oxidative pretreatments a requirement to increase gold recovery. Pretreatment alternatives include roasting, pre-aeration, acidic and alkaline high pressure oxidation, and bacterial oxidation. The presence of arsenic, however, introduces a serious disadvantage to the use of roasting and bacterial leaching, while high pressure oxidation involves high capital costs. The use of carbonaceous materials to enhance the dissolution of sulfides is not novel, and leaching additives such as coal, activated carbon and carbon powder have been considered for the improvement of bioleaching, atmospheric leaching, and pressure oxidation leaching processes. However, this type of technology has been focused mainly on the recovery of copper from copper concentrates containing chalcopyrite with less attention paid to other sulfides."

Jan 1, 2017

By A. Himsley

This paper presents a review of the existing ion exchange resin systems for treating unclarified pregnant liquor, with particular reference to uranium extraction. A new concept of a truly continuous ion exchange system is described and operating details are given,of a 0.6.-m (24 in.) diameter pilot plant treating unclarified acid leach liquor.

Jan 1, 1977

By T. Orser

In 2010 Newmont made the decision to purchase a 42 foot (ft) Semi-Autogenous Grinding (SAG) mill from Metso and a 28 Mega-Watt (MW) Gearless Mill Drive (GMD) from ABB for the Conga Project in Peru. The test and study work showed that a single line 42 ft SAG mill circuit gave the most favorable project economics in comparison to an equivalently powered single line 40 ft SAG mill circuit. This paper does not address the process design or the project economics, but instead focuses on the key aspects of the SAG mill design, GMD design and the associated component manufacturing. This paper also addresses, where applicable, the potential reliability differences between the initially proposed 40 ft SAG mill and the finally accepted 42 ft SAG mill.

Jan 1, 2012

By P. Favreau

This paper describes the progress accomplished at the Noranda Technology Centre in the field of three-dimensional computer-aided underground blast design. Traditional methods of laying out underground blasts are reviewed, and the new computer-aided approach is described. Time savings achieved through the use of BLASTCAD can be advantageously used to better engineer blasts, using models and blast vibration analysis. Future work involving the attachment of blast models directly to the system is also addressed.

Feb 1, 1993

By C. Stamberg, W. McGuire, R. C. Carlson, L. W. Vollmer

"The selection of materials and pre-cautionary measures for handling natural gas and condensate containing aqueous hydrogen sulphide are presented. Based on the results of a pilot production test and laboratory studies, together with several years . of operating experience, it was found that the behaviour of materials in sour gas environments can be predicted sufficiently accurately for engineering purposes.The selection of proper materials is essential for preventing sulphide-stress cracking. Where high strength materials are not required, low car-bon steel is used. Components requiring high tensile strength and hardness characteristics should be made from K-monel or properly heat-treated carbon-manganese-molybden-um and AISI 4140 steels. Welded connections are a potential source of sulphide-stress cracking. Consequently high quality welding and strict inspection are suggested as the most economical precautionary measures available.A maintenance program based,. where possible, on visual inspection of equipment and/or test spools located at strategic points should be used to follow weight loss and putting corrosion in sour gas environments. If severe weight loss or pitting corrosion is encountered, inhibitors have been found to be an effective deter-rent."

Jan 1, 1960

By Sunil S. Gandhi

"Uranium occurrences are widely distributed in tuffaceous-argillaceous beds and abundant rhyolitic volcanic rocks of the upper Aillik group, which is more than 3 km thick and over 125 km by 40 km in areal extent. They include partially developed Kitts and Michelin deposits, containing 1560 and 7366 t U respectively.Uranium occurs mainly as disseminated fine pitchblende grains in beds and lenticular stratabound zones, and rarely as coarse pitchblende aggregates and thin veinlets. The Kitts deposit and ten other occurrences are in the argillaceous-tuffaceous beds within a steeply dipping stratigraphic zone, less than 50 m thick and over 20 km long, at the base of the upper Aillik group. The occurrences hosted by the rhyolitic rocks, numbering over fifty and including the Michelin deposit, are in elongate structural-stratigraphic belts or zones, and are characterized by a pronounced enrichment of soda and depletion of potash associated with mineralization. The mineralized zones are affected to a varying degree by Hudsonian deformation, metamorphism and granitic intrusions.The uranium mineralization is interpreted as genetically related to the felsic volcanism, involving syngenetic deposition in argillaceous-tuffaceous beds and epigenetic emplacement in rhyolites. The volcanic activity occurred 1855 ± 5 Ma ago according to a preliminary U-Pb zircon date on porphyritic rhyolite. Pitchblendesfrom the Kitts and Michelin deposits and a few other occurrences in rhyolites have yielded nearly concordant dates in 1810 to 1730 Ma range. They reflect resetting of isotopic equilibrium at the time of Hudsonian deformation. Other isotopic data on pitchblendes and galena from veins and aggregates .in the south near the 'Grenville Front' indicate local redistribution of uranium and radiogenic lead at the time of Grenville Orogeny approximately 1100 Ma ago."

Jan 1, 1986

By N Robb

This paper gives an account of the laboratory testing, plant testing and final inclusion of the two-stage sulphuric acid leaching process in the Milliken mill. Operational results for September, 1962, are presented, showing a uranium extraction of 95.5 per cent, with a saving of some 16 lbs. of 100 per cent H~S04 and some 9 lbs. of lime per ton milled. Methods for effecting further improvements in the process are indicated. HISTORY P RIOR to the incorporation of two-stage leaching, the process for the treatment of uranium ores at Milliken consisted of a single-stage sulphuric acid leach, followed by a solution recovery step involving washing in thickeners and two-stage filtration. The thickener overflow solution was subsequently concentrated and purified by ion exchange, and the uranium was recovered, by two-stage precipitation, as ammonium diuranate. Figure I illustrates this flowsheet. For satisfactory extraction of uranium from the. Milliken ore, a high residual acidity, of the order of 40 grams per litre of free acid in the discharge solution, must be

Jan 1, 1963

By Robert Macdonald, William Coombe, John F. Lewry

Gold occurrences have been known in the La Ronge Domain for many year . Mineable reserves have more recently been outlined and there is every prospect of a major gold camp being established in the domain within this decade. The La Ronge Domain lies in the Lower Proterozoic 'Trans-Hudson Orogen' and is part of a collage of Early Proterozoic crust comprising volcanoplutonic arcs, batholiths, associated volcaniclastics and volcanogenic sediments lying between the Superior Craton to the outheast and the reworked Archean basement/Aphebian cover terrain to the northwest. The domain has several lithostructural subdivisions, the most important of whjch , from a gold exploration point of view, is the Central Metavolcanic Belt. This belt is composed dominantly of a range of metavolcanic rocks and gabbroic to granitic intrusives, which geochemically resemble younger subduction-generated 'primitive' arcs developed on oceanic crust. U-Pb zircon geochronology indicates that the arc volcarusm and pre- to late-kjnematic plutonism occurred about 1890 Ma to 1850 Ma ago. The belt has an attained grade of upper greenschist to amphibolite facies and is relatively undeformed , though high strain zones occur locally. Most gold occurrences in the La Ronge Domain have been found in the Star-Waddy Lakes area of the Central Metavolcanic Belt, and in the Sulprude-MacKay Lakes area to the south which is interpreted as a tectonically dismembered part of the main belt. Both tratiformand vein-type gold occurrences are present in the domain; vein-type predominate and form nearly 90 per cent of the occurrences. The stratiform-type occurrences show a regional lithological a sociation with iron-rich sediments within proximal felsic volcanjc sequences. Some vein-type occurrences appear related to brittle fracturing associated with intrusive emplacement (the magmatic-hydrothermal "syn:' and "subvolcanic" veins) and faulting. However, most of the vein-type occurrences exhibit a spatial association with regionalscale ductile shear and other high strain zones, and were probably formed by metamorphichydrothermal processes.

Jan 1, 1986

By P. D. Waters

"Mineral deposits are where you find them; they have no allegiance to territorial boundaries. Over the past decade much of the new investment in mining has been outside of continental North America, let alone Canada. The larger Canadian Banks have pursued this offshore business through their multi-national organizations; this reflects both the increasingly international orientation of today's business environment, and to a degree, the competitive advantage of these offshore developments.The current oversupply situation in mineral markets and the increasing maturity of the Developed World Economy reduces the need for new mining projects relative to growth' in GNP. Those that are brought on stream in the future due to their competitive advantage, will continue to be pursued by lenders and equity investors alike. IntroductionProspects facing those who search for mineral wealth were described rather well more than 200 years ago by a Scottish professor of moral philosophy, who also happens to be the father of modern economics.In search for new mines, Adam Smith wrote in The Wealth of Nations, ""there seems to be no certain limits either to the possible success or to the possible disappointment of human industry"".How true that statement remains today, where we are seeing economic cyclical problems compounded by basic fundamental structural change within the mining industry.Despite the enormous advances in earth sciences during the past two centuries, the rewards of mineral exploration still remain uncertain. Even though a promising orebody is found, ultimate profitability may still depend on the vagaries of the marketplace, where large and unanticipated changes in supply, demand and prices can play havoc with the best of calculations.The Canadian mining industry has had its share of disappointment during the past few years, with savage competition, shrinking demand, declining prices, and disappearing profits. But it has also had some share of success, such as at Hernlo, which now seems certain to provide some of the lowest cost gold production in the world"

Jan 1, 1986

By S. Power Warren

Introduction It is generally conceded by flotation men that the condition at the surface of a particle of mineral or gangue is the most important factor controlling its behaviour in a flotation cell. Much research work has been devoted to the study of the forces that are active at the surface of the particle and of the effect of the surrounding solution upon these forces. Study of the relationship between mineral or gangue particles and gas bubbles indicates that, in the main at least, flotation is a physical phenomenon. The important factor, that of mineral-gas-bubble attachment, is unquestionably physical; however, modifications may be effected by chemical means, whereby the nature either of the surface of the particle or of the surrounding solution may be changed. For example, the coating of lead sulphide that forms on lead-carbonate ore particles when sodium sulphide is added greatly aids the flotation of the carbonate particles. Without going into the question as to why, under certain surface conditions, mineral particles will attach themselves to gas bubbles whereas under other conditions they will remain unaffected, it may be stated that there are three general conditions in a flotation pulp which control the attachment of the particle and the gas bubble.

Jan 1, 1933