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By J. M. Skeaff

"The main solution, ore and residue pulp streams in the Rio Algom Quirke I uranium mill at Elliot Lake have been sampled and analyzed for radium-226. Analysis of the ore and leached residues indicates that Ra-226 dissolves and precipitates within the first pachuca tank. A maximum of approximately 0.2% of the Ra-226 in the ore remains in solution during leaching.IntroductionConcern over the acid drainage and radionuclide dissolution problems associated with uranium tailings disposal sites in Canada has prompted investigation into methods for improving current uranium processing practice.Present commercial practice usually involves leaching of the uranium ore with sulphuric acid, ion-exchange separation of the uranyl sulphate complex from the leach liquor and"" precipitation of the uranium as yellowcake. Daughter products of U-238, such as Th-230, Pb-21O and Ra-226 remain with the tailings and undergo long-term dissolution.Table I summarizes the probable behaviour of the radionuclides during milling. The concern here is with Ra-226, because it will deposit in the bones if ingested and is ""thus considered a serious health hazard(1), Similarly, Po-218 and Bi-214, which are daughter products of Rn-222, can be retained in the lungs and are considered to be the principal sources of radiation dosage(2) arising from the inhalation of Rn-222. Previous investigations(3-9l indicate or imply that Ra-226 undergoes redistribution during milling. However, detailed published information on the behaviour of Ra-226 in the uranium milling process appears to be lacking. A knowledge of the behaviour of Ra-226 in uranium mills, particularly during leaching, could lead to improved methods for its control.This paper reports the occurrence of Ra-226 in the Rio Algom mill. The main objectives of the study were to determine (1) the distribution of Ra-226 within the solids, (2) at what point, and how rapidly, redistribution occurs and (3) whether there are high concentrations of Ra-226 in solution."

Jan 1, 1981

By H. P. Whaley

This paper introduces Wabush Mines, including its ownership, physical assets, capacity, goals and achievements. It is to be followed by four papers which will present the detailed story. Wabush Mines, the largest supplier of iron ore to the Canadian steel industry, was brought into production in 1965. The ore is mined and concentrated in Wabush, Labrador, Newfoundland and pelletized at Pte. Noire, Quebec. Annual capacity is over 6,000,000 tons of high-grade iron ore pellets.

Jan 1, 1969

By Jan Butra

In copper ore mines located in the Pre-Sudeten Monocline the deposit mining using room and pillar systems has been carried out for more than forty years. When implementing mining systems in deep copper ore mines it appeared to be necessary to adapt them to variable geological conditions and natural hazards. In the initial period of exploitation there were mainly caving and rockburst hazards. The adaptation of room and pillar system was connected with a state of knowledge in the scope of identifying, forecasting and controlling rock mass hazards. The new solutions allowed the safe and efficient exploitation of a blanket deposit of variable thickness from about 2 to 15m, seated on progressively increasing depth. They included exploitation in constrained conditions, such as in protective pillars. In the exploitation period, technical and organisational activities aimed at rockburst hazard control were introduced including active methods for controlling rockburst hazard and procedures for conducting mining works in the rockburst hazard conditions. When mining at a depth exceeding 1,200 m, the exploitation method and technique are additionally affected by thermal hazard and by gas and rock breakout hazard. New solutions of the room and pillar system and a longwall system with mechanical mining have been developed for exploitation in the associated hazard conditions. The require application of many innovative solutions in the scope of mining process and ore haulage mechanisation, excavation support and forecasting and control of existing hazards. The main purpose of these solutions is to conduct the safe and economically effective exploitation of the deposit.

Aug 1, 2013

By I. A. Kovalevska

Considered problems: elaboration and implementation of resource-saving technologies, low-cost support systems improvement, openings security and support, based on wallrock condition control with supreme implication into the rock pressure occurrence counteraction work. Results of analytic and underground investigations using computer simulation of the finite elements in order to calculate stressstrain state of the multivariable geomechanical systems are presented. Solutions of concrete objectives are found using spatial geomechanical model of solid motion around openings, considering real geomechanical parameters formation of support forms with proper conditions of their contact and real mechanical characteristics. Ultimate solutions of resource-saving technologies implementation based on the analysis of multivariate vertical, horizontal, and reduced stresses components calculation and also near-contour rock, support bearing components and security constructions movements are found. Results of experimental investigations of combined supports and security constructions, which increase openings' stability in difficult conditions of flat coal seams are presented.

Aug 1, 2013

By M. S. Greenfield, E. Cocchiarella, S. Chubbs

"At Dofasco sNo.4furnace a variation of the basic oxygen steelmaking process, Klockner Oxygen Bottom Maxhutte (K-OBM), is used to produce steel. Large amounts of hot gases and particulate are evolved during the oxygen blowing phase. A quencher and a venturi scrubber are used to collect over 99.5% of the particulate. In 1990, the authors investigated the effect of foamy slag on the particulate emissions from the furnace. The amount of lime added early in the oxygen blowing cycle was reduced, making the slag more viscous and foamy for a six minute period. Instantaneous particulate emissions were monitored throughout the blow by analyzing quencher and venturi scrubber water samples. Particulate emissions were reduced up to 59% during the foamy slag period.IntroductionThe reduction of the amount of waste generated or control of emissions at source is at the top of the ""3R"" hierarchy of waste management (Reduce, Reuse, Recycle). Process and operating practice changes are often the most economical ways to control emissions. At Dofasco, they investigated the effect of operating practice changes, specifically the formation of a foamy slag, on particulate emissions from steelmaking furnaces. They wanted to determine if a foamy slag changed the quantity and nature of the fume evolved from the K-OBM furnace over the oxygen blowing phase.The Basic Oxygen Steelmaking ProcessesThe basic oxygen steelmaking process (BOP) generates large quantities of very fine metal oxide fume during the production of steel. In this process, scrap steel and molten iron (hot metal) from blast furnaces are charged into a steelmaking furnace. Then pure oxygen is injected and a lime flux added . The oxygen reacts with carbon dissolved in the molten iron to form carbon monoxide. Oxygen lances can have secondary nozzles which introduce oxygen above the bath. This secondary oxygen, known as post-combustion, bums some of the carbon monoxide radiating the heat back to the bath. Particulate and gases rich in carbon monoxide are ejected from the furnace during the oxygen blowing phase and are collected by a gas cleaning system. Typically, more than 99.5010 of the particulate is scrubbed from the gases by high energy venturi scrubbers or electrostatic precipitators. The oxide sludge or dust collected may have elevated zinc and lead which is unsuitable for recycle to blast furnaces. Due to the presence of these undesirable elements, treatment and disposal of steelmaking oxide dust is difficult and costly."

Jan 1, 1993

By Dean Gerhardt

Why the need for proactive loose detection? ?? Past history of ground falls in Saskatchewan mines prompted research into new techniques for ground control. ?? Traditional tools for ground assessment (i.e. visual inspection, sounding with scaling bars) are not proactive and can often be time consuming. ?? Need existed for a system that was non-evasive, time efficient, and could be managed by a single operator. Ground Penetrating Radar (GPR) immerged showing the greatest potential.

May 1, 2008

By J. E. Carter, D. P. Wall

"This paper details the highlights of the open-pit and underground operations of Mclntyre Mines Limited in the Smoky River area of Alberta. Mining methods, operating equipment and manpower are outlined, followed by a discussion of reclamation and environmental control.IntroductionMcintyre Porcupine Mines Limited was incorporated in 1911 and for many decades was known primarily as a gold producer in the Porcupine district of northeastern Ontario. The company, however , has held coal leases in the Smoky River area, near Grande Cache, Alberta, since 1921. Preliminary studies were carried out in the region from 1959 to 1963. In 1964, Mitsubishi, a leading Japanese trading company, (on behalf of Mcintyre), investigated the area as a possible source of coal for the Japanese steel industry. The initial report concluded that Smoky River coal was of high quality, comparable with some of the best metallurgical coals in the world."

Jan 1, 1981

By Matt Manson

?? Current Exploration and Assessment ?? Overview of Potential Development ?? Infrastructure ?? Opportunities and Challenges ?? Renard? 1-10 kimberlite pipes and ?Lynx-Hibou? kimberlite dyke system within ?Foxtrot? property ?? 50/50 Joint Venture between Ashton (a subsidiary of Stornoway) and SOQUEM ?? Discovered 2001-2003 ?? Québec is routinely assessed as one of the top mining jurisdictions in the world ?? Agnico-Eagle Mines Ltd. Is Stornoway?s largest shareholder and a leading mine developer in Québec

May 1, 2008

By David L. Anderson

This paper explores the financial impact of the initial version of the Saskatchewan Potash Reserve Tax; first, a one; and second, in conjunction with the other taxes affecting the industry's profitability. A though the introduction of the Reserve Tax is shown to lead to a substantia increase in a hypothetical firm's effective tax burden, the more unusual outcomes frequently attributed to this levy on y occur after the imposition of other non-provincial tax rulings. Despite this qualification, the results obtained suggest that the Reserve Tax undoubted y acted as a catalyst in the polarization of attitudes during the ear y period of industry/government confrontation

Jan 1, 1979

By L. A. Mells

"A laboratory test program was initiated by the Department of Energy, Mines and Resources as part of the National Uranium Tailings Program to investigate the applicability of a radium selective ion exchange complexer for removing radium from Canadian uranium mining effluents. The test program was carried out by Melis Consulting Engineers Ltd. under contract to the Department of Supply and Services using the Saskatchewan Research Council facilities located in Saskatoon, Saskatchewan.The results of this work showed the ion exchange complexer, Dowex XFS 43230.00, to be efficient in removing radium from contaminated water of uranium mining operations with the ultimate loading capacity of the resin on one type of water treated being determined as approximately 1,600 Bq/cm3 of new resin. Although this resin has potential application for treatment of effluent streams in uranium operations it has been identified that the resin efficiency and capacity is directly related to the chemistry of the water being treated and site-specific testwork is required in order to establish reliable design data for full-scale operations.IntroductionThe possible applicability of a radium-selective ion exchange complexer for removing radium from Canadian uranium mining effluents had been identified and discussed as a possible alternative to present radium removal methods during a review of disposal technology options for the National Uranium Tailings Program of the Department of Energy, Mines and Resources(1). Work by other workers(2.3) had shown the complexer to be very efficient in removing radium from contaminated water. Also, plant trials on contaminated minewater at the Mt. Taylor uranium mine in New Mexico is reported to have shown the resin complexer to be efficient under plant operating conditions.As a result, a laboratory test program was initiated by the Department of Energy, Mines and Resources as part of the National Uranium Tailings Program to investigate the suitability of this resin for Canadian uranium mining effluents. The test program was carried out by Melis Consulting Engineers Ltd. (MCEL) under contract to the Department of Supply and Services using the Saskatchewan Research Council (SRC) facilities located in Saskatoon, Saskatchewan."

Jan 1, 1985

By Navid Bahrani

Overview ? Case history of footwall slab failure ? Procedure used to build a finite element model ?? Pre- and post- mining topography ?? Slab geometry ?? Excavation stages ?? Input parameters ? Finite element modelling results ?? Unloading-induced displacements (magnitudes & directions) ?? Calibration of overall model using measured prism displacements ?? Shear stresses and displacements along the base of slab ?? Factors of safety at different stages ?? Effectiveness of rock bolts ?? Staged or unstaged model? ? Conclusion

May 1, 2008

By Denghong Wang

Abstract- The Ashele Cu-Zn deposit is a recently discovered volcanogenic massive sulfide deposit in Xinjiang, China, hosted by Lower to Middle Devonian submarine bimodal volcanic rocks. The primary ores of this polygenetic deposit are represented by massive syn-depositional pyrite, chalcopyrite, and sphalerite, and were formed by submarine exhalation. Hydrothermal alteration consists of strong sericitization, chloritization, silicification, and carbonatization of the metavolcanic rocks beneath the massive orebodies. Depletion of Na2O is an obvious chemical change in the hydrothermal halo. Geological and geochemical evidence suggest that the Ashele Cu-Zn massive sulfide deposit was formed by submarine exhalation related to bimodal volcanic rocks, trapped in a rifting basin, then deformed by shearing, and thermally metamorphosed by the intrusion of dacitic porphyry. Sulfur and lead isotopic studies indicate that metals such as copper and zinc may have originated from spilites, but that volatile components, especially sulfur, were derived directly from submarine volcanic magmas.

Jan 1, 1999

By H. B. Gillis

THE following pages c9ntain a brief description of the processes involved in the manufacture of silica brick at the Sydney plant of the Dominion Steel & Coal Corporation. Silica brick manufacture was commenced at Sydney in 1918, for the purpose of supplying the requirements of the steel plant, where about three million silica bricks were used annually. Previous to that date, all silica refractories were brought to Sydney from American sources and were subject to a freight cost of nine dollars per ton, or about twenty-seven dollars per thousand. As a preliminary step to manufacture, a thorough investigation of all possible sources of silica in the vicinity of Sydney was carried on during 1916 and 1917. ?Eighteen separate deposits were examined. Of this number, only four were found suitable for brick making, and the Leitches Creek silica, being the nearest of these four deposits to Sydney, was selected as the raw material for the proposed plant. CRYSTAL MODIFICATIONS OF SILICA A brief review of the silica minerals may serve to indicate why careful investigation of sources of supply is necessary before actual brick-making is attempted. The crystal modifications of silica, i.e., quartz, tridymite, and cristobalite, all possessing alpha and beta phases, play a most important part in determining the suitability or otherwise of the resulting brick. By heat treatment, any one of these forms of silica may be converted to either of the others. The inversion temperatures (after Fenner) in degrees Centigrade are shown on rage 160.

Jan 1, 1938

By A. LA. Salama, D. B. Hyma

"The Western Research Centre (WRC) of CANMET located in Devon, Alberta, is a modern research facility offering services ranging from fundamental research to pilot plant investigations. Recently, a 0. 76 metre diameter by 7.9 metre high Flotaire column flotation cell was installed as a demonstration unit for Canadian coal producers. Because the column cell is intended to be used for research, development and demonstration, WRC recognized that additional sensing equipment and improved process control would be required to generate good data for subsequent column scale-up and engineering design.A low cost, personal computer based control system was, therefore, designed and installed. This paper describes the stepwise procedure in developing the control strategies, selection of system software and hardware, and installation and configuration of the system.Preliminary performance data on a western Canadian coal sample are also presented. Future testwork is planned on additional coal samples to expand upon existing database."

Jan 1, 1993

By P. A. Gonzalez Contreras

Scorodite is considered as a secondary mineral formed from the product of weathering of primary minerals by chemical or biological reactions. In the case of biological scorodite formation, microorganisms mimic and accelerate what in nature takes a very long time, i.e. biocrystallisation. The goal of the biological scorodite formation is to form very stable arsenic crystals suitable for long-term and safe disposal. The biological formation of scorodite is a novel combination of biological oxidation, biocrystallisation, and proper bioreactor design to achieve the biological formation of scorodite crystals in one step. We have explored simultaneous biological arsenic and iron oxidation at 30ºC and at 70ºC leading to arsenic-jarosite phases and scorodite, respectively. As biologically formed scorodite crystals are very stable (TCLP < 1 mg/L As (V)), the risk of arsenic toxicity is minimized when leaching takes place. This process is suitable for arsenic concentrations above 0.5 g/l As achieving up to 20 mg/l As in the effluent. This biological scorodite formation system is a selfsufficient bio-oxidation system and therefore many new applications can be explored such as reprocessing of arsenic trioxide, orpiment or calcium arsenate to scorodite crystals for a stable and safe disposal.

Jan 1, 2014

By M. C. Ethier, A. L. Laramie

"The Granisle and Bell Copper mines were officially put into production in 1966 and 1972, respectively. The Granisle Mine was purchased in late 1979by Noranda and the two operations were amalgamated as one division. Both mines were closed in 1982after sustaining heavy financial losses during a period of low copper prices beginning in 1981.This paper describes the resumption of operations at the Bell Mine in 1985 after its shutdown period of three years and the dramatic and sustained improvements in productivity and efficiency realized as a result of a commitment by employees and management to the application of Participative Management and Employee Involvement principles. After a general description of the effects of such a philosophy on the operation as a whole, and a comparison to the operation&apos;s last full year as a producer, it deals with the practice of this philosophy in the maintenance department at the Bell Mine and the superb results realized.IntroductionThe Bell Copper deposit was discovered in 1963 and came onstream as a 10000 ton s per day open pit mine in the fall of 1972. Identified reserves at that time were 46 million tons of ore containing 0.50% copper. The mine shared facilities of the townsite of Granisle with the nearby Zapata-Granby mine which had established the community six years earlier.Because of easy grinding ore and improvements to milling circuits, Bell&apos;s throughput rate was increased to 17 000 tons per day by the late 1970s. In the open pit, improvements resulted in mining of additional reserves with higher stripping ratios. At startup, a half ton o f waste was mined for every ton of ore processed.By the end of 1982, with 48.2 million tons already mined, the Bell Mine had identified additional mineable reserves of 39.4 million tons containing 0.52% Cu.In November 1979 the Granisle Mine was purchased from Zapata-Granby. The two mines, with a total of 700 employees, were operated under common management as the Babine Division until 1982 when low copper price s forced the closure of both for an indefinite period.The outlook for copper prices remained bleak and only 50 people were retained on the payroll to maintain the two plants, most of them working on a part-time schedule.The population of the Village of Granisle dwindled from over 1500 inhabitants to under 500, as people moved away to seek other employment.Prior to the shutdown, the Bell Mine employed 370 people and pit extraction averaged nearly 50000 tons per day of which 16000 tons was mill feed, and the remainder waste. Total cost to produce a pound of copper was C$1.36 in 1982."

Jan 1, 1990

By A. Proulx

Durant les années 1955 à 1961, plusieurs campagnes d?exploration ont été menées sur la zone Bond dans la partie sud-ouest de l?anneau nord de la carbonatite d?Oka (propriété de Niocan, figure 1). Les zones minéralisées HWM1 et HWM2 sont découvertes à l?ouest de la propriété. Un des forages, le S-60, avait intercepté 80 mètres de minéralisation à 0.71% Nb2O5 à l?est des zones HWM1 et HWM2 mais aucun autres travaux d?exploration n?avaient été réalisés sur cette interception minéralisée. En 1995, Niocan réalise une campagne de forage pour mieux définir la zone minéralisée recoupée par le forage S-60. En 1997, une seconde campagne de forage détermine un tonnage de 14.37 Mt avec une teneur de 0.66 % Nb2O5 pour la zone S-60 (Marcotte et Gagnon, 1997). Le complexe carbonatitique d&apos;Oka se situe à environ 35 km à l?ouest de Montréal sur la rive nord du lac des Deux-Montagnes. Sa formation remonte au Crétacé précoce (entre 117 à 123 Ma). La carbonatite d?Oka fait partie de la suite d&apos;intrusions alcalines que constituent les collines Montérégiennes. Le complexe a une forme allongée (7.2 km par 2.4 km) orientée NO-SE (figure 1). Il est intrusif dans des roches précambriennes constituées d?anorthosites au nord et de gneiss charnokitique au sud (Gold, 1963) appartenant à la Formation de la colline d?Oka. Les gneiss au contact du complexe sont fénitisés sur une épaisseur qui peut atteindre jusqu?à 60 mètres. Les roches carbonatitiques forment la série dominante du complexe et elles sont composées principalement de calcite (> 50 %) à gros grain et parfois rubanées. Les minéraux accessoires les plus communs sont la biotite, le pyroxène, la monticellite, la magnétite, l?apatite, la forstérite, la mélilite, le pyrochlore, la pérovskite, la niocalite, la pyrite et la pyrrhotite (Gold, 1963).

May 1, 2003

By Ali Montaser

This paper presents an experimental study conducted to facilitate the use of RFID on construction job sites. The study focuses on deployment settings to provide data acquisition with higher accuracy for indoor location sensing. It provides extension to the state-of-the-art in this field as it addresses the impact of metal media proximity to RFID tags, the reasonable duration for data capturing, number of RFID tags employed and the distance between them. Low cost passive RFID tags were used in the experiments where each tag is used as a reference point with a known location. Five hundred and forty (514) experiments were conducted in lab environment using a 3m by 3m test bed that is dynamically rearranged to generate 15 test beds and a total of 67713 data sets were collected and analyzed. The collected data were captured from nine locations for each test bed at four time intervals. Received Signal Strength Indicator (RSSI) was used as the main attribute for signal measurement to process the captured data. Results of the data analysis performed are studied under four main categories: duration, number of tags, locations of tags and metal interference. The best duration was found to be the 15 second in the test bed with the least number of tags; as the short amount of time to capture data did not allow creation of a lot of interference among the emitted signals. Within each test bed, errors occurred most at points where the received signals were not well distributed in a 360 degree vicinity of the data capturing point. It means that the center point of each test bed resulted in lowest errors and the points located on the extremities led to the highest errors. Finally, metal objects were found to have major impact on the accuracy of the captured data; to the level where reliable values for errors could not be calculated in the test beds attached to metal objects. In summary, the results of the experimental study and related findings are expected to provide guidelines to the users of RFID technology for localization in building construction.

Aug 1, 2013

By Francis Breton, Lei Pan, Kun Liu

"Effects of Fe, Cu and Mg minor alloying elements on creep properties of 8xxx aluminum conductor alloys were investigated by conducting compressive creep tests at 100 ºC under a constant load of 69 MPa. The microstructural evolution was studied using an optical microscope and electron backscatter diffraction technique. The creep properties were characterized by the primary creep strain in the first stage and the minimum creep rate in the second stage of creep deformation. Results showed that additions of all three minor alloying elements (Fe, Cu and Mg) demonstrated a beneficial effect on the creep resistance but individual alloying elements exhibited different impacts on creep properties. The additions of Fe and Mg showed a strong impact on both the primary creep strain and minimum creep rate, while the Cu addition displayed a favorable effect on the primary creep strain but no impact on the minimum creep rate. Microstructure observation revealed that with increasing Fe contents, the volume fraction of fine intermetallic dispersoids gradually increased while the subgrain size and misorientation angle became smaller, providing strong barriers to the dislocation and grain boundary movements. The addition of Cu moderately reduced the subgrain size and misorientation angle and in combination of solid solution strengthening it promoted the retardation of the creep deformation during the primary stage.INTRODUCTIONThe 8xxx aluminum conductor alloys offer significant advantages such as low density, high conductivity to weight ratio and low price over copper conductors and become an attractive candidate in electrical engineering and building wiring (McQueen, Chia, & Starke, 1986; Birol, 2009; Engler, Laptyeva, & Wang, 2013). The mass resistivity of aluminum conductors is one-half of copper conductors. Thus, only one-half the weight of aluminum is required for equivalent capacities. Therefore, this unique property coupled with a relatively low price of aluminum offers significant economic advantage to develop aluminum conductor alloys for electrical applications in the electrical wire industry."

Jan 1, 2016

By D. M. Slavich

"In today&apos;s operating and investment climate, project evaluation is both more important and more difficult. It is more important because economic and financial analyses of a proposed project provide a basis for judgment of a project&apos;s commercial viability by equity participants, lenders and, in some cases, other participants such as off takers and governments. It is more difficult because these analyses must, of necessity, be based on estimates, projections and evaluations which must be made in a period remarkable for its economic and political uncertainty.Project evaluation starts with the analysis of the engineering, commercial and financial information available. Beginning with the preliminary design and capital cost estimates, alternative financing plans can be developed outlining possible sources of funds, terms and security arrangements. Pro-forma financial statements can also be developed, including sources and uses of funds, cash flow schedules, income statements and balance sheets. With these results, various profitability measures can be determined.Subsequently, in an effort to deal with uncertainty, these results can be tested by measuring the impact on project viability and profitability of changes in project and external variables such as product process, mining and processing rates, operating and financing costs, currency exchange rates and other factors.The results are a number of financial projections reflecting different assumptions for key project parameters. The projections can be used to structure the project to achieve the maximum financial performance. Projects, the financial viability and profitability of which can be demonstrated under varying market conditions, will be the most competitive in capital markets."

Jan 1, 1982