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By Michael T. G. Brown

Syncrude Canada Ltd. has recently completed construction of its ambitious tar-sand mining and processing facilities at Mildred Lake, Alberta. The Syncrude site is approximately 48 km (30 miles) north of Fort McMurray near the west shore of the Athabasca River. The Syncrude operation involves the open-pit mining of approximately 270,000 tonnes (300,000 tons) of tar sand daily using draglines and a conveyor system. Bitumen is extracted from the tar sand, upgraded to oil-gas and transported to refineries in Edmonton and other locations for final processing . The Beaver Creek Dam forms part of the mining facilities for the Syncrude tar-sand mining operation. Water from Beaver Creek is diverted from the open-pit mine site south to the Athabasca River via Ruth Lake and the Poplar Creek Dam. General site layout is shown on Figure I . Design of the dam was completed by R. M. Hardy and Associates Ltd. of Edmonton, Alberta (now Hardy Associates (1978) Ltd) . Construction was undertaken during the summers of 1974 and 1975 under the direction of Canadian Bechtel Limited, managing contractors for Syncrude Canada Ltd. Total length of the dam is approximately 2.8 km (1.7 miles), with a maximum height in the order of 16 m (50 ft) The Beaver Creek Dam is located in a broad, flat, poorly drained valley. About 50 per cent of the site is covered with treeless peat deposits, which ranged in thickness from in excess of 5 m (15 ft) at the east end of the dam to less than 1 m (3 ft) at the central portion. The peat deposits overlie Pleistocene meltwater sediments on top of clay/clay shales of the Clearwater Formation and the tar sands of the McMurray Formation. The peat deposits and high groundwater levels at the site combine to make the excavation and construction of a conventional rolled clay cutoff impractical. For these reasons, the slurry cutoff trench technique was utilized to produce an efficient and effective seepage cutoff under various sections of the Beaver Creek Dam .

Jan 1, 1979

By D. Eriksen

Zero Emission Gas power, ZEG, is a novel concept where a high temperature solid oxide fuel cell (SOFC) is integrated with a reforming reactor producing hydrogen from natural gas through Sorption Enhanced Steam Methane Reforming (SESMR). The SOFC is used as a high temperature heat source for regeneration of the CO2-absorbent. Moreover, by using part of the produced hydrogen as fuel for the SOFC, the waste heat of the process is considerably reduced. Thus, the process has a very high thermal efficiency and produces both electricity and hydrogen from natural gas. In addition, a stream of pure CO2 is produced in the regeneration step and can be deposited or used commercially. Initial cost estimates indicate a cost of electricity and a cost of hydrogen well below today's prices. A small (1kWel + 1kW H2) demonstration set-up is under construction and experimental results and related research will be presented. This set-up comprises one 2.5kWth H2 SESMR-reactor (about 0.85 Nm3/h H2) operating batchwise with dolomite as the CO2-sorbent. The reactor developed is designed like a parallel plate heat exchanger where the mixture of sorbent and reforming catalyst is packed between the heat exchanging plates. The demonstration set-up includes a 1kW SOFC operating in a continuous mode. The set¬up will therefore demonstrate continuous simultaneous hydrogen- and electricity production, but cannot demonstrate simultanuous electricity- and CO2-production. The set?up is well equipped for on-line monitoring of gas composition, flows and temperatures. This important part of the demonstration set-up is developed and provided by Christian Michelsen Research (CMR). A minor part of the project is the development of a continuous circulating fluidized bed SESMR-reactor system and in another related project the focus is on the development of more suitable sorbents. In these two projects co-operation with University of British Columbia and Lousianna State University, respectively, is highly appreciated.

Jan 1, 2005

By Brian Lewis

"IntroductionThe leaching method selected for the dissolving of uranium ore depends in part on the physical characteristics of the ore, as well as the uranium mineralization. There are two main methods of leaching employed in uranium circuits in North America, one being ""Carbonate Leaching"" on sandstone, and pitchblende type ores, and ""Acid Leaching"", on quartzite type ores.This chapter deals with the acid leaching of uranium ores found in the Elliot Lake area, using sulphuric acid, for the leaching reagent, and ""pachucas"" for the contactor.The basic leaching process involves the pregrinding of the ore and the mixing of the ore with hot sulphuric acid, the mixture is air agitated, the air being used to oxidize the ore as well as produce agitation. The chemical reaction is as follows: Uranium Oxide + Sulphuric Acid = Uranyl SulphateThe following equations show the actual dissolution of the ""Hexavalent Uranium"", which show that more than one ion or complex of uranium is possible.Uranium DissolutionsI. UO, + 2H-(UOJ + H,O2. (UO,) + SO, = -UO, SO, (Uranyl Sulphate)3. UO, + SO,-(UO, (SO,),)=4. (UO, (SO,),)= -(UO, (SO,),)'Test work carried out in the laboratory as well as in the plants has determined the most efficient methods of extracting the uranium from the ore. A very important factor that has to be determined during initial test work are the amount of acid consumers in the ore. Within the Elliot Lake orebodies are minerals such as chlorite schist, diabase, and basement material, all very high acid consumers, consuming up to 1000 lbs. of acid per ton of ore. Of these minerals only the chlorite schist contain any uranium at all.The following are the operating parameters that have to be controlled in the plant:I. sulphuric acid concentration2. temperature of the mixture3. agitation4. liquid solid ratio5. reaction time6. particle size of ground ore"

Jan 1, 1989

By M. P. Du Plessis

"The paper discusses coal research in relation to the special needs of Western Canada, with its large resources of lignite and subbituminous coals. Research programs are presented under the following headings: Coal Liquefaction, Pyrolysis, Fluidized-Bed Technology, Underground Coal Gasification and Supporting Investigations. Typical processes are presented and their relevance to Canadian coals is described. The longterm plan of the Alberta Research Council for coal research and the steps taken for its implementation are discussed. Finally, some innovative concepts arising from basic research in coal chemistry are discussed.Canada's Coal ResourcesCanada is richly endowed with coal reserves. With estimated ultimate reserves of 600 billion tons in O.76-m (2.5-ft) thick seams under less than 762 m (2500 ft) of overburden, Canada rank s fourth after the USSR, the USA and Chinatu (see Table I) . Canada's reserves are incompletely explored and estimates are constantly being upgraded. Preliminary information from deeper test-hole logs suggest that similar , if not larger, tonnages occur at depths greater than 762 m (2500 ft).The types of Canadian coals and their regional Distribution(2) is shown in Figure 2. Alberta's subbituminous Plains coal represents about 70% of estimated national reserves. A large portion of the coal can be mined at relatively low cost by surface mining techniques, and it is currently being used exclusively for power generation in conventional thermal plants. This coal, however , also represents a large potential .source of liquid fuels which could equal or exceed that of oilsands and heavy oil. Table 3 compares Federal Government estimates for resources and reserves of fossil fuels in Canada and their recoverable oil content or equivalent.A conservation estimate of only the reserves of thermal coal represents an oil equivalent of 27.6 billion barrels , which equals the recoverable reserves of oil-sand bitumen and heavy oil. A more realistic estimate is probably several times this amount. Although coal can be converted to many other end products, such as fuel gas and synthesis gas for hydrogen and ammonia production, liquid fuels remain the most desirable product mainly because they can be transported more cheaply over long distances and their high energy density makes them uniquely suitable as fuels for transport and agriculture."

Jan 1, 1981

By Gene O. Cowie

"Zinc, which once enjoyed an unchallenged position in the field of decorative applications, has lost a substantial share of its markets to other materials, particularly plastics. This turn of events has led the zinc industry to explore new market areas, particularly those applications where the engineering properties of zinc can be utilized. This paper gives an overview of the zinc industry's efforts to develop the data base and product development technology which have enabled zinc alloys to emerge as engineering materials. It also indicates those areas in which the research facilities of the zinc industry must be employed to ensure that zinc alloys keep pace with developments in competitive materials and processes.The Materials RevolutionThe development and utilization of new materials and manufacturing processes progressed for centuries by evolution. Recently it erupted into a revolution, which may become as significant as the industrial revolution. The materials revolution has impacted upon many industries, but none has been affected more traumatically than the North American automotive industry. The plight of that industry is of great importance to us because their problems have, to a great degree, become problems to the zinc industry.Much of the impetus behind the automotive trauma came from the battery of motor vehicle regulations promulgated by the United States government in the 1970s. These regulations required that the efficiency of passenger cars, in terms of miles per gallon, be approximately doubled in ten years. In view of the fact that major changes in the automotive world require three years of lead time to implement, the industry was left with only seven years to perform the task. The automotive industry was simultaneously required to make progress in other areas, such as reduced emissions, reduced cost of repairs and increased levels of occupant safety. These added demands not only diverted some of the available resources away from efficiency goals, they often ran in direct conflict. For example, when you are required to provide a front bumper which will absorb the energy of a 5-mile -per-hour barrier collision, you must add both hardware and structure to the vehicle. This adds weight, and increased weight reduces miles per gallon."

Jan 1, 1983

By M. Kuyumcu

With annual production of almost 3.5 million metric tonnes of K20, former East Germany (GDR) was the world?s third-largest producer of potash, ranking behind only the Soviet Union and Canada. More than 80 % of production was intended for export to earn urgently needed hard currency. For this reason, beginning in the 1970s, East Germany began to mine unprofitable hard-salt sources and carnallitite fields, which are geomechanically problematic. In the course of restructuring from a centrally planned to a market economy after German reunification, only two of the nine existing potash mines were classified as economically viable for privatization. All six potash mines in the South Harz Region were closed between 1991 and 1993. The orderly safekeeping of these potash and other decommissioned ore mines and the rededication of mining areas were assigned in 1992 to a German state-owned company GVV founded especially for this purpose. Elaboration in the present documentation covers the local necessity of the type and extent of filling and safeguarding measures. As a result of the remedial measures taken, it was possible to prevent the collapse of cavities and damage to surface facilities. This documentation describes the safeguarding successes to date, with appreciable reduction and stabilization of surface settlement and with significant lessening of seismic events. Also presented are concepts updated to the state of the art for safeguarding of numerous potash mining shafts for long-term effectiveness in separation of the workings and watercourse levels in the cap rock. In the course of 100 years of production, six mining dumps resulted with a total volume of approximately 170 million m3. They consist of up to 95 % of water-soluble salts. Every year, precipitation dissolves up to 500,000 tonnes of this salt, which enters as a highly concentrated solution into watercourses and ground water. Explanation follows of measures for minimization of environmental pollution by covering of dumps and controlled drainage of alkaline solutions from the dumps. Finally, presentation is made of the results of the successful work until now by GVV for reuse of decommissioned mining sites with settlement of new companies for creation of additional jobs and for revitalization of the monostructured South Harz Potash Mining Region.

Aug 1, 2013

By D. A. Whitley, R. P. Carone

"Shaft sinking by blind shaft drilling offers the mining industry a different approach to shaft construction. Benefits of blind drilling include less construction time and fewer safety problems while being economically competitive with conventional sinking methods under certain conditions in soft water-bearing formations.Technology and equipment are available today to drill blind shafts up to 20 feet in diameter and over 3,000 feet deep. This is an extension of proven techniques developed by private industry. To drill a 20-foot-diameter hole requires a specially manufactured hydraulic drill unit with a rated hoist of 2 million pounds and 500,000 ft/lb of torque.This brief paper will discuss the following aspects of blind shaft drilling:• benefits;• equipment f or drilling;• circulation methods;• circulation rates;• shaft alignment; and• progress rates to be expected.IntroductionShaft sinking by blind shaft drilling offers the mining industry an improved alternative method for shaft construction. The drilling of 20-foot -diameter shafts to depth s in excess of 3,000 feet can be done by utilizing equipment specifically designed and manufactured for this purpose. This equipment is a distant cousin, at best, to standard oil well drilling rigs. The actual configuration of these drilling machines will be discussed in a following section.To most people, the drilling of mine shafts may seem to be a new or at least recent technology. However, as early as the I920s, German and Dutch miners were drilling 24-foot diameter shafts for coal mines. What led ""miners to resort to drilling were ground conditions that still plague conventional shaft sinkers today: soft , water-bearing formations. The major drawback to these early attempts was a low penetration rate due to poor bit cleaning. This, however, was not the end of early shaft drilling activity. From 1936 to 1950, a number of mine shafts were drilled by the calyx or coring method. This method employs a bit with a large bore down the center. As it drills, it cuts a core. When 5 to 10 feet have been drilled, the core is removed. The disadvantages of this method were the time and work involved in breaking the core free, and it was inadequate in soft water-bearing ground."

Jan 1, 1981

By N. E. Chaouai, M. Lavigne

"Indicator kriging is one of the non-parametric geostatistical techniques, ideal for estimating the reserves of irregular mineralizations (e.g. gold, uranium, platinum, diamonds, etc.). Such mineralizations are characterized by variograms which are very sensitive to extreme values (outliers) and very difficult to model.The classical approach to this problem in the industry is to trim off these high grades using arbitrary empirical upper limits established either from practice or subjectively. Contrary to this simplistic approach, indicator kriging discretizes the histogram of the grades (usually log normal) in several classes and carries out interpolation separately for each class. This paper gives an overview of the differences between ordinary and indicator kriging along with the steps required to carry out indicator kriging. The paper concludes with a case study involving a gold deposit estimation.IntroductionParametric geostatistics (ordinary kriging) has given us satisfactory results over the years in estimating the reserves of well behaved deposits with coefficients of variation close to 1 (e.g. sedimentary and porphyry type deposits). However, numerous problems have been encountered in estimating irregular mineralizations (e.g. small vein deposits of precious metals) with high coefficients of variation in the range of 2 to 5. Such deposits are characterized by a very small proportion of extreme values (outliers) which create distortions on the variograms (pure nugget effect) and render them useless(1,2).The solution often followed by the mining industry today is to trim off these values based on empirical limits. These limits are derived either by comparison with production results (or bulk samples) or by geological interpretations. Needless to say that such manipulations can lead to serious errors in estimating ore reserves (usually underestimation of total metal quantity), especially when production results or bulk samples are absent.On the other hand, the solution followed by the geostatisticians in the past was to smooth out the data using transforms (e.g. normal-score or natural logarithms). Such transforms are nonlinear and they required non-linear estimation techniques such as disjunctive kriging (DK) or multivariate gaussian kriging (MG) which require normal related hypotheses, not necessarily true in geology.Nonparametric geostatistics (indicator and probability kriging) have been -developed in order to handle these problems related to highly skewed distributions."

Jan 1, 1990

By R. M. Giegerich

"This paper begins with a brief history of Madawaska Mines, a brief description of the geology, mining methods and equipment, and the historical development of 7/8-in. tapered drilling equipment. It then outlines the performance characteristics and inherent problems of the traditional 12-degree, tapered connection, blade-type insert bits. Service-free (Unipass) button-type insert bits are presented as a possible solution to these problems. The paper concludes with an analysis of button bit performance to date.Brief History of Madawaska MinesMadawaska Mines Limited, near Bancroft, Ontario, is in Faraday Township, Hastings County, approximately 100 miles northeast of Toronto and 100 miles west of Ottawa.The mine re-opened in 1976committed to 1,500 tons per day to provide approximately 600,000 pounds of yellowcake (U3O8) per year to A.G.I.P. (an Italian government agency) under the joint ownership of Federal Resources Corporation, Salt Lake City (51%), and Consolidated Canadian Faraday Limited (49%). At present, the mine is producing approximately 2 pounds per ton (.1% U3O8) at the rate of 60,000 pounds per month. The mine employs about 400 employees.Brief Description of Geology, Mining Methods and EquipmentGeologyThe Grenville metasediments of the mine area are chiefly paragneiss, amphobolite and some carbonate (marble) rocks, which were intruded by a basic rock, altered to a metagabbrometadiorite. These formations are generally concordant, striking east to northeast and dipping 45 to 60 degrees to the south. Locally, the metagabbro is often discordant. The above group of rocks (mixed hybrid gneisses) forms the hanging wall of the south-dipping Faraday granite sheet and was intruded by nepheline syenite, syenite and granite. The ore occurs in the granite-syenite-pegmatite dykes that are probably genetically related to the Faraday granite. The ore shoots are erratically distributed within the pegmatite bodies, mainly on the hanging or footwalls but also medially. Their size varies from 50 to 350 feet in length, 5 to 40 feet in width and 50 to 200 feet in height. The ore occurs most frequently in a medium-grained granite or syenite, well hematized with 10 to 30% mafic crystals of pyroxene, amphibole and/or relics of the host rock."

Jan 1, 1982

By P. Mayer

"Determining the correct mechanism of a boiler tube failure is important for the prevention of future tube failures. Proper corrective measures can be undertaken to alleviate the root cause or causes for a failure only when the correct mechanism is known. A mechanism of boiler tube failure is defined as the process which degrades the tube and produces a failure.An expert system package was developed for use by electric utility power plant personnel during investigation into the cause of a boiler tube failure. It is intended to assist their efforts to recognize and identify a basic failure mechanism that can produce the type of boiler tube failure under investigation. The program guides the user to the most likely failure mechanism by asking simple questions, answers which can be obtained by determining the failure location, type of fuel, and from visual inspection of the failed tube. Expert systems are a form of artificial intelligence which imitate the decision-making process of experts.IntroductionBoiler tube failures (BTFs) continue to be the single largest source of forced outages in fossil fired electricity generating stations. Because of this a concentrated effort is being made to minimize boiler tube failure occurrences. Eliminating boiler tube failures could be worth $5 billion a year to the electric power industry(1).The aggressive service environment of fossil-fired boilers is largely the reason for these failures because the combined effects of stress, temperature, corrosion, erosion and vibration cause deterioration of boiler tube material properties and reduction in wall thickness.Determination of the boiler tube failure mechanism is important for the prevention of future problems. The root cause for a failure can be established and proper ameliorative measures taken only when the failure mechanism is identified correctly. The correct identification of failure mechanism is a complex process which may include many individuals and institutions. Technical specialists in metallurgy, chemistry, combustion, and boiler design frequently cooperate with the station staff in a failure investigation . These individuals rely on personal experience and numerous reports , theories, studies, private communications and investigations concerning the different failure modes and mechanisms."

Jan 1, 1990

By David Deglon, Martin Harris, Mehdi Safari

"This study investigates the effect of energy/power input on the flotation of a platinum ore in a pilot-scale oscillating grid flotation cell. Oscillating grids generate near ideal hydrodynamic environments, characterised by turbulence which is relatively homogeneous and isotropic. Secondary rougher feed and primary cleaner tail streams were floated in a pilot-scale oscillating grid flotation cell at power inputs from 0 to 2.5 W/kg, using 0.50 and 1.50 mm bubbles. From this study one may conclude that the effect of energy/power input on the flotation rate is strongly dependent on the particle and bubble size. Flotation rates generally increase with increasing particle size and decreasing bubble size. Increasing energy input generally leads to an increase in the flotation rate for finer particles and an optimum flotation rate for intermediate & coarse particles. Optimum conditions for intermediate/coarse platinum ore particles are using small bubbles at low energy inputs, or large bubbles at higher energy inputs. These results suggest that higher energy inputs are generally beneficial for the flotation of platinum ores as these consist predominantly of finer particles (-75 µm) and most industrial flotation applications operate with larger bubbles (1.0-2.0 mm).INTRODUCTIONThere is a considerable body of experimental and theoretical evidence to suggest that energy/power input plays an important role in flotation kinetics, particularly in the finer particle sizes where flotation efficiency is poor (Deglon, 2005). A number of excellent studies into the effect of energy on flotation kinetics have been carried out in impeller stirred cells (Ahmed and Jameson, 1985; Deglon, 2002; Pyke et al., 2003; Newell and Grano, 2006). Investigations using this type of cell have a number of limitations. The impeller influences particle suspension, bubble break-up and agitation in the cell. In addition, turbulence is highly inhomogeneous and anisotropic, with power intensities near the impeller orders of magnitude higher than those found elsewhere in the cell (Deglon, 1998; Koh and Schwarz, 2003; Schubert, 1999, 2008). These limitations have resulted in the development of novel cells for the investigation of energy input."

Jan 1, 2016

By K. Schimann, H. D. Knipping, J. P. Fouques

"The Cigar Lake uranium deposit, in the Athabasca area of north Saskatchewan, was discovered in May 1981 by Cogema (Canada) Ltd., as operator of the Waterbury Lake Joint Venture.The deposit, which is devoid of direct surface expression, is located at the unconformity between the Lower Proterozoic (Aphebian) Wollaston Group meta-sediments and the Middle Proterozoic (Helikian) Athabasca sandstone, at a depth of 410 m to 450 m below surface.At the end of 1984, the deposit had been defined by 105 mineralized holes over a length of 1800 m and a width of between 25m and 105m. It has the shape of flat-lying /em 5 m to 30m thick and shows a remarkable longitudinal and lateral continuity from the information obtained to date. A well defined bulge of the unconformity underlies the mineralized zone over its entire length.The deposit appears to be controlled by an east-west trending structure within which a particular rock facies (""augen gneiss'') has developed in the graphitic metapelites of the Wollaston Group. It is surrounded by a strong alteration halo affecting both sandstone and basement, characterized by extensive development of Mg-AI rich clay minerals (illite-chlorite). The mineralization is hosted principally by the Athabasca sandstone, and consists mainly of uraninite and sulfa-arsenides of nickel and cobalt. Numerous geochemical and geophysical surveys have been carried out in the Cigar Lake area, and although no specific geochemical or geophysical anomaly can be directly associated with the mineralized body, there may be locally a good coincidence.However, a combination of several methods proved extremely useful in interpreting the regional geology and defining the drilling targets within the favourable areas.Although the Cigar Lake deposit shows many similarities with several classical deposits of the Athabasca region, it is characterized by the intensity of its alteration processes and the presence of massive, extremely high grade mineralization.At the end of 1984, the global geological reserves estimated by geostatistics on the main mineralized ""pod"" of the deposit amounted to 110,000 metric tonnes of uranium at an average grade of 12.2% U, with a precision of 25% at the 95% confidence level."

Jan 1, 1986

By M. R. Babcock

"The Rabbit Lake story began in the late sixties and will continue well into the twenty-first century. It is a story of success, of multiple ore body discoveries, of unique systems, and new methods made possible through innovative and state-of-the-art design. Two quite different geological systems host the five ore bodies mined, or slated to be mined. These two systems have yielded two distinct ore types, each with characteristic mineralogical properties and each requiring its own specific mill circuit.Emphasis on communications and our unique systems have led to a satisfactory and fulfilling work environment resulting in the historically low employee turnover which has contributed to the operation success.A comprehensive environmental study after twelve years of operation has given the Rabbit Lake Operation a completely clean bill of health. INTRODUCTIONRabbit Lake can be described as Saskatchewan's first highgrade uranium mining operation, which set the stage for the province's current role as the leader in uranium mining throughout the western world. The importance of the Rabbit Lake operations - past, present and future.LocationThe Rabbit Lake operation is located in northeastern Saskatchewan (Fig. 1)- 805 km north of Saskatoon, Saskatchewan, and 814 km northeast of Edmonton, Alberta. OwnershipGulf Minerals Canada Limited discovered the Rabbit Lake deposit in 1968. Mining operations began in 1975and were operated by Gulf until purchased by Eldorado Nuclear Limited in 1982. In 1988, Eldorado merged with Saskatchewan Mining Development Corporation (SMDC) to form Cameco-A Canadian Mining &. Energy Corporation. The new corporation is one of the world 's largest uranium companies.Cameco's $1.5 billion in assets include the Rabbit Lake uranium mine (Cameco 100010); the Key Lake uranium mine (Cameco 66.67%; Uranerz Exploration and Mining Limited 33.33%); the Cluff Lake uranium mine (Cameco 20%; Amok Ltd. 80%); the Fuel Services Division at Blind River and Port Hope, Ontario (Cameco 100%); and a 100%); and a 48.75% interest in the Cigar Lake uranium deposit which is now at the test mining stage (Cogema Canada Ltd . 32.625% ; Idemitsu Uranium Exploration Canada Limited 12.875%; Corono Grande 3.75%; Korea Electric Power Corporation 2%). In addition, Cameco is involved in a number of base and precious metal explor ation projects."

Jan 1, 1989

By David L. Huston, Wouter Bleeker, Bruce E. Taylor, Ron Cook, Bob Stewart, Elizabeth R. Koopman

"Abstract—Detailed oxygen isotope mapping of rhyolites in and around the Kidd Creek mine indicates that the orebodies are associated with relatively low (<12‰) whole rock values that extend up to 200 m laterally from ore. The zone of low d18O values is overlain stratigraphically by a carapace of higher (>13‰) values that extends up to 1.5 km laterally from and 300 m to 500 m above ore. Immediately above the stratigraphically highest orebody this carapace is cut by a zone of lower d18O values extending from the ore zone. Zones of higher d18O values also occur in massive rhyolite bodies that occur in the footwall of the orebodies.The zone of low d18O values partly coincides with a Na2O depletion anomaly associated with hydrothermal alteration, except that the Na2O depletion anomaly has a greater lateral extent, and the low d18O anomaly extends farther into the stratigraphic hanging wall. These data suggest that d18O mapping may detect hanging wall alteration above massive sulfide bodies more effectively than conventional lithogeochemistry. Zones of high d18O values, which define zones through which large quantities of low-temperature hydrothermal fluids have passed, may also have usefulness in exploration.Oxygen isotope variations at Kidd Creek record three stages of a hydrothermal system that evolved in temperature with time, as follows: (1) an early, low-temperature event that produced rocks with high d18O values, (2) a high-temperature event that produced rocks with lower d18O values, and (3) a later, low-temperature event that also produced rocks with high d18O values. The high d18O signature of the massive rhyolite was recorded during early-stage, low-temperature (<200°C) alteration, and was probably preserved owing to decreases in permeability associated with low-temperature silicification. The low d18O signature of cherty breccia and chloritite was recorded during the thermal peak at >300°C. High d18O values in the carapace above the deposit were recorded as the hydrothermal system waned."

Jan 1, 1995

By David L. Huston, Wouter Bleeker, Bruce E. Taylor, Ron Cook, Bob Stewart, Elizabeth R. Koopman

"Abstract-Detailed oxygen isotope mapping of rhyolites in and around the Kidd Creek mine indicates that the orebodies are associated with relatively low (<12‰) whole rock values that extend up to 200 m laterally from ore. The zone of low d18O values is overlain stratigraphically by a carapace of higher (>13‰) values that extends up to 1.5 km laterally from and 300 m to 500 m above ore. Immediately above the stratigraphically highest orebody this carapace is cut by a zone of lower d18O values extending from the ore zone. Zones of higher d18O values also occur in massive rhyolite bodies that occur in the footwall of the orebodies.The zone of low d18O values partly coincides with a Na2O depletion anomaly associated with hydrothermal alteration, except that the Na2O depletion anomaly has a greater lateral extent, and the low d18O anomaly extends farther into the stratigraphic hanging wall. These data suggest that d18O mapping may detect hanging wall alteration above massive sulfide bodies more effectively than conventional lithogeochemistry. Zones of high d18O values, which define zones through which large quantities of low-temperature hydrothermal fluids have passed, may also have usefulness in exploration.Oxygen isotope variations at Kidd Creek record three stages of a hydrothermal system that evolved in temperature with time, as follows: (1) an early, low-temperature event that produced rocks with high d18O values, (2) a high-temperature event that produced rocks with lower d18O values, and (3) a later, low-temperature event that also produced rocks with high d18O values. The high d18O sig- nature of the massive rhyolite was recorded during early-stage, low-temperature (<200°C) alteration, and was probably preserved owing to decreases in permeability associated with low-temperature silicification. The low d18O signature of cherty breccia and chloritite was recorded during the thermal peak at >300°C. High d18O values in the carapace above the deposit were recorded as the hydrothermal system waned."

Jan 1, 1995

By R. H. McCorkell

"Sample drops were evaporated on Lexan disks on which fission tracks were etched and counted after neutron irradiation. [U] = 0.01 ppb could be measured. This method is rapid, cheap, simple and accurate when sufficient control and checking is possible, but several types of error were encountered in its use, the natures and sources of which were investigated but not always determined. The most troublesome were ""annealing"" processes which sometimes altered the fission tracks so that they were not fully revealed, or acquired varying appearances, after etching. Several different annealing processes seemed to exist and seemed to be produced by alteration of the Lexan surface by dissolved components in the solutions and, perhaps, by radiation and local heating during neutron irradiation. The appearances of the etched tracks varied with the natures of the droplet solutions even when annealing appeared to be absent, and for this reason, standards are best prepared by additions of known amounts of U to sample solutions. Contamination of sample droplets by U-containing dust from the air is best avoided by preparing the disks away from areas where other U-analysis is being carried out.IntroductionFission tracks are regions of radiation dam age produced in solids by the fission of atoms such as 235U. They can be enlarged to sizes visible through optical microscopes by etching surfaces through which they pass with solvents in which the solids are slightly soluble. A sample to be analyzed for U may be placed against a film of a solid of negligible uranium concentration (the track detector) and irradiated with thermal neutrons in a nuclear reactor to fission 235U. The track detector is then etched and the number of tracks per unit area, ?, which is proportional to the uranium concentration of the sample, c, and the neutron do se, n, is found by counting through a microscope. Uranium in solutions ha s been measured by evaporating drops on track detectors, irradiating, etching and determining the number of tracks per drop, T(2,3,4,5). Extensive test s of this method are reported here."

Jan 1, 1983

By T. Robson

"A multi-seam underground mining operation employing mechanized room-and-pillar methods provides 35 per cent of Smoky River's annual ROM coal production (2 million tonnes) from the Smoky River coal field. Surface mines provide the balance. Tectonic activity, which has resulted in deformed coal seams and a rugged relief to the area, has provided natural boundaries to discrete mining areas. Coal transportation to the central preparation plant incorporates a 3 km long underground conveying system. The company is committed to efficient resource recovery and a safe and healthy working environment. Introduction The Smoky River Coal operations (SRC) are centered in the Smoky River coal field located in west central Alberta, some 360 km west of Edmonton and 20 km from the Town of Grande Cache (Fig. 1). Combined mining operations produce 2 million tonnes per year run-of-mine coal from which 1.65 million tonnes of high quality, low volatile, coking coal are obtained. The underground mining operation, employing mechanized room-and-pillar methods, provides 35 per cent of SRC's annual ROM coal production (2 million tonnes). Surface mines provide the balance. Tectonic activity has resulted in deformed coal seams and a rugged relief in the area. This has provided natural boundaries to discrete mining areas. Background Exploration of the Smoky River coal field took place over four decades commencing in 1926. McIntyre Mines Limited (parent to Smoky River Coal Ltd.}, commenced development of the property in 1968 having secured a long-term contract for the delivery of coal to Japan. Production of underground coal at Smoky River commenced toward the end of 1969 and has been continuous on the property since that time. Originally, two underground mines were opened. Original planning envisaged the use of room-and-pillar techniques to develop blocks of coal for subsequent extraction by longwall retreat mining. Following initial development, two longwall units were established, the first in November 1970 in No. 5 Mine and the second in February 1971 in No. 2 Mine. Difficulties were experienced on both units, and production commitments could not be achieved. The longwalls were discontinued, and mechanized room-and-pillar was subsequently used for all underground mining."

Jan 1, 1985

"Eastern Canadian thermal coal mined at Minto, New Brunswick, and in western Cape Breton at St. Rose, Inverness County, Nova Scotia, contains 6-8 per cent sulphur. Both coals are high volatile bituminous. types. The Minto coal averages 18 per cent ash, 7 per cent sulphur and has a Btu rating of 11,900 per lb. Pyritic sulphur accounts for 75 per cent of the total sulphur and the remainder is largely organic; the amount of sulphate sulphur is negligible. This means that in a 7 per cent sulphur coal, 2 per cent is organic and 5 per cent pyritic sulphur. Pit-head St. Rose coal contains approximately 10 per cent ash, 7 per cent sulphur and 11 ,800 Btu/lb. The distribution of sulphur is different to that of Minto coal because about 12 per cent sulphate sulphur is present. Thus, a 7 per cent sulphur coal would contain 4 per cent pyritic, 2 per cent organic and 1 per cent sulphate sulphur.The iron sulphides, pyrite and, to a lesser extent, marcassite occur over a wide size range from large sulphur balls to crack fillings, lenses, and individual crystals and framboids. Coarse-grained pyrite and sulphur balls are easily separated during washing. It is the fine grain sizes, intimately mixed with the coal constituents, that are difficult to separate. Quantimet analyses of the fine grains in coal from both localities showed that about 50 per cent were smaller than 30 micron(1).No efforts have been made to wash the Inverness coal of Nova Scotia and in 1980 washing ceased in New Brunswick. Previously, the Minto coal was processed in an antiquated jig circuit which reduced ash from the strip operation run-of-mine value of more than 20 per cent to less than 18. More effective removal of ash and sulphur could clearly be obtained. Laboratory tests on both Minto and St. Rose coal have shown that ash rejection rates of 40 to 50 per cent at yields of 70-80 per cent were possible(2), Little information on sulphur removal was available."

Jan 1, 1981

By Gerhard Heinrich

"The composition and the possible utilization of a slag sample from a nickel smelter operation in the Sudbury district were investigated. The sample containing 0.136% Ni, 0.10% Co and 0.29% Cu could be characterized as a fayalit e slag with a sulphide bearing glass matrix. While the fayalite contains most of the Co, Ni is enriched within both sulphides and fayalite. Cu is only present in higher amounts in sulphides or metallic droplets. This, as well as the small grain sizes of the mineral phases, inhibits significant enrichment by mechanical methods. However preconcentration is possible by means of magnetic separation. An effective hydro metallurgical approach proved to be oxygen pressure leaching with sulphuric acid. Accordingly, the method proposed for processing the investigated slags is to combine the normal utilization as coarse construction material with pressure leaching of the fines and the ground upgraded magnetic fraction. Besides the recovery of base metals, the leaching process yields fine-grained residues, which, after addition of CaD, will set to a cement-like material, or can be used as a pozzolanic cement colour. INTRODUCTIONDuring the pyro metallurgical processing of nickel ores, the valuable metals nickel, cobalt and copper are enriched within the sulphide matte, similar to the smelting of copper ores. The resulting waste materials are slags, which may still contain valuable metal contents of up to 0.5% or above . These contents are close to the cut-off grades of some nickel-cop per-cobalt deposits. The methods that are used to recover copper from slags comprise in general further pyro metallurgical treatment, often after enrichment by flotation. Another area of application for such slags is their use as construction material. However, this might cause environmental problems if nickel containing dusts are produced.Based on one example, the characerization and a possible way of complete utilization of nickel smelter slag s as construction materials in combination with partial base metal recovery are described in this paper. The investigated slag sample was obtained from a dump site in the Sudbury district, Ontario. Detailed test series for process optimization were not possible during this study due to the limited available sample size."

Jan 1, 1989

By D. W. I. Griffiths, J. C. Bélanger

"La Division Matagami de Minéraux Noranda inc. a profité de la construction de sa nouvelle mine (Isle-Dieu) pour continuer sa modernisation.L&apos;utilisation d&apos;automates programmables (PLC) s&apos;est intensifiée pour contrôler et automatiser de plus en plus d&apos;équipement dans ses minessouterraines, au concentrateur, dans les atelierset bureaux.Tous les PLC comrnuniquent entre eux et les IBM PC sont utilisespour exterioriser l&apos;information et faire Ie lien entre Ie personnel et les automates. Le système Central IBM 36 emmagasine les donnees traitees par lesPLC (a travers les PC). Ces donnees sont transmisesau programme d&apos;entretien de chaque equipement et compile les heures, cycles, tonnes, etc., fait imprimer automatiquement les feuilles d&apos;entretien préventif &apos;, etc.Les principales realisations adate et en progrès pour la mine Isle-Dieu sont:• automation complète du système de remblayage du concentrateur ala mine Isle-Dieu situee a2 km de la mine principale;• automation du fonctionnnement des ventilateurs qui comprendra la position des portes de ventilation, Ie chauffage, Ie débit, etc.;• automation des pompes, surveillance des sous stat ions électriques, concentration des gas (CO, SO2) à chaque niveau en tout temps et du propane à l&apos;entree d&apos;air frais;• tonnage et cycles par Ie treuil; et• contrôle d&apos;autres équipernents à differénts niveaux. D&apos;autres travaux furent egalement effectues par les employes, tels que:• la conversion d&apos;un Scooptram ST5A de diesel à électrique;• I&apos;installation complete de systèmes de depoussierage a I&apos;eau (scrubber) pour le concassage secondaire;• I&apos;installation d&apos;un marteau hydraulique avant les concasseurs coniques;• la rénovation des cellules de flottation ; et• l&apos;installation d&apos;un système de gardiennage par caméra. D&apos;autres projets seront effectués ou étudiés:• automation d&apos;un Scooptram"";• automation d&apos;un marteau hydraulique;• récupération de Scooptrarn; téléguidé:• gestion de l&apos;énergie, contrôle de la demande, surveillance et contrôle de l&apos;équipernent de machines fixes(compresseurs, boulloires, pompes à vide, génératrices, débits et pression d&apos;air, eau pour diagnostiquer les problémes, analyser les coûts;• concasseur portatif pour fabriquer de la pierre concassée pour utiliser dans les chemins sous-terre, et• utilisation de micro-ondes pour transmettre les images captées par camera."

Jan 1, 1990