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By J. T. Birkholzer, M. Rutenberg, K. -H. Lux, R. Wolters, J. Rutqvist, L. Blanco Martin

In this paper, we present numerical results corresponding to the Thermal Simulation for Drift Emplacement (TSDE) test, conducted in the Asse salt mine (Germany) between 1990 and 1999 to simulate reference repository conditions for spent nuclear fuel in rock salt. This test is of significant relevance for nuclear waste disposal in salt because extensive research and measurement programs were set up for the experiment. In our numerical study, we use two sequential simulators, TOUGH-FLAC and FLAC-TOUGH, and we investigate two-way coupled processes, focusing on thermo-mechanical analyses due to the main effect of heating. The two simulators used have recently been updated and are able to deal with large strains and creep processes. Moreover, specific constitutive relationships and coupling functions for rock salt and crushed salt under repository conditions are available. Within the framework of a benchmark exercise between Lawrence Berkeley National Laboratory and Clausthal University of Technology, the same scenario has been modeled in three dimensions using the two simulators mentioned. The main objective of the current, first stage of the benchmark is to evaluate the capabilities of these two simulators to predict relevant processes under repository conditions for high-level nuclear waste in saliniferous media. The comparison of the numerical predictions between them is very satisfactory, leading to a successful code-to-code verification. The comparison between measurements and numerical results shows that the most important processes are captured by the codes and constitutive models used. However, some differences exist between measurements and numerical results. These differences will be addressed in the next stage of the benchmark exercise, in which a parameter fitting effort will be undertaken. Overall, from the results obtained it can be concluded that TOUGH-FLAC and FLAC-TOUGH have the necessary capabilities to reproduce relevant processes under repository conditions for high-level nuclear waste in saliniferous formations.

Jan 1, 2015

By Michael J. Beus

The National Institute of Occupational Safety and Health-Spokane Research Laboratory (NIOSH-SRL) have developed a Shaft Conveyance Monitoring System (SCMS). Assessment of current hoisting technology has shown that monitoring wire rope tension and conveyance position and load directly from the skip or cage top offers several significant safety, production, and maintenance advantages. The SCMS consists of conveyance position and guide displacement sensors, a battery power supply and charging system, and a new sensor to measure hoist rope tension. This device provides a warning of the occurrence of ?slack rope? a particularly dangerous condition. A 2.4 GHz radio link transmits data to the hoistroom. A reduced scale hoisting test facility has been constructed to test these components prior to field trials. The advantages of monitoring wire rope tension and conveyance position and load directly from a skip or cage top will be discussed. Field tests are underway in full-size shafts to refine the concept and evaluate long-term reliability and maintenance requirements. Application of this technology may result in decreased maintenance costs as well as safer, more productive hoisting operations.

May 1, 2001

By D. C. Treilhard

After a brief history of the mining and smelting operations of Kilembe Mines Limited, this paper outlines the smelter layout and describes . the. daily operations at the Jinja plant. Particular attention 1s paid to the details of the furnace and converter operation. A subsequent section of the paper deals with the significant developments in plant metallurgical practice, covering both smelting and converting.

Jan 1, 1966

"Since World War II, urban communities have expanded at an unprecedented rate. The industrial mineral industry supplies the sand, grave], limestone, crushed rock, cement, gyp-sum, etc. for urbanization. Most de-posits in use are close to or within communities. Pollution of water and air has become a matter of public concern. Waste disposal and the effects of noise and vibration are subjects of public debate. Need for the reclamation of land after operations such as strip mining is discussed in magazine articles and on TV pro-grams; i.e., the general public is educated in the unattractive features of mining.Legislation is on the books and being drafted to regulate mining operations and their side effects. To avoid over-regulation and restrictive legislation, it is necessary that the public be educated and legislators informed of problems peculiar to the mining industry. Our side of the story needs publicity."

Jan 1, 1968

By Frank D. Shepherd

THE Gunnar Gold Mines property is on the west shore of Beresford lake, in the Rice Lake mining division, southeastern Manitoba. Gold was first discovered in place in the Rice-Beresford Lakes area in 1911 on the Gabrielle claim, now included in the San Antonio Mines property at Rice lake. Following an eastward trend of favourable prospecting ground, promising showings were next staked in the vicinity of Long lake during the years 1915 and 1916. At that time, William Walton and associates, among them Gilbert LaBine, staked the Eldorado vein, north of Long lake, and Eldorado Gold Mines, Limited, was formed to develop the property a Company that, later, was to become widely known through successful operation of its radium-silver mine at Great Bear lake, Northwest Territories. Continuing eastward from Long lake, Walton and his partners, Gunnar Berg, Leo Seaberg, and Wm. Quesnel, staked claims during the years 1920-24 in the vicinity of Beresford lake which, later, were to become incorporated into the Gunnar Gold Mines property. The presence of gold-bearing quartz on these claims had been known from the time they were staked, but an opportunity to consolidate them into a group was not forth-coming until early in the year 1933. Although promising gold showings had been disclosed during the performance of assessment work on individual claims, no continuous mineralization having mine-making possibilities was discovered until after the consolidation of the entire group. From this stage onward, progress was rapid. Active exploration was begun on August 1st, 1933, and late in October James Houston reported favourably on the property. On October 27th, Gunnar Gold Mines, Limited, was incorporated in the Province of Ontario to develop and operate the property. The Company is also registered in Manitoba. The authorized capitalization is 3,000,000 shares of $1.00 par value. Gilbert LaBine was appointed president of the Company, with James Houston as mine manager. Following completion of a diamond-drilling programme, planned in 1933, it was decided to install a mine plant capable of carrying development to a depth of 1,000 feet. A transmission line, 5 miles in length, was built to the Great Falls-Central Manitoba line of the Manitoba Power Company, Limited.

Jan 1, 1939

By Z. Zhang, M. -Y. Liu, X. -G. Chen, F. Breton

"The microstructures of AlSi10Mg foundry alloy in permanent mould (PM) and high pressure vacuum die (HPVD) castings were analyzed and compared. The as-cast microstructures of two castings mainly consisted of eutectic silicon particles, primary Mg2Si and Fe-rich intermetallic phases. The surface layer in HPVD castings, which has a unique feature and different structures, was carefully characterized. The dimension variation of microstructural phases along the cross section in PM samples is less than that in HPVD samples, although the size of microstructural phases in PM samples was much larger than that in HPVD samples. The mechanical properties of PM and HPVD samples were evaluated on as-cast and T6-treated conditions. The tensile properties of HPVD castings are remarkable better than those of PM castings on the as-cast condition. The T6 heat treatment greatly improves the tensile strength of PM castings while it has limited impact on the tensile strength of HPVD castings.INTRODUCTION The AlSi10Mg alloys are widely applied to the high pressure die casting (HPD) and high pressure vacuum die casting (HPVD). In the HPD process, the melt is injected into the die cavity under a high speed (30–50 m/s in the gate velocity for aluminum alloys), and solidified under a high pressure (up to 200 MPa in the cavity) and with a high cooling rate (up to ~103 Ks–1) (Gourlay, Laukli & Dahle, 2007; Ji, Wang, Watson & Fan, 2013). This results in a unique microstructure feature that is different to other casting processes under gravity. One major concern in HPD castings is porosity due to trapped air in the cavity (Ji et al., 2013), which seriously restricts the application of a heat treatment on the improvement of mechanical prosperities because of the formation of blisters on casting surfaces. For the process improvement, the high pressure vacuum die casting was developed in 1980s (Uchida, 2009). In this process, the melt is injected into the die cavity under reduced pressure (vacuum), which greatly reduces gas porosity in castings due to effectively avoiding the trapped air. Consequently, HPVD castings are heat-treatable without the formation of blisters on castings surface during heat treatment. The HPVD process has been widely applied to produce high quality structural castings in recent years attributed to reliable vacuum system development (Uchida, 2009). However, the microstructure features of HPVD castings are not systemically characterized yet."

Jan 1, 2018

"Real-time, on belt analysis of minerals is becoming increasingly important and critical in modern operations, especially in the mine-to-mill. Prompt gamma neutron activation analysis has long been utilised for real-time elemental analysis in bulk materials, with Scantech's GEOSCAN being the instrument of choice in the minerals sector. Working in the minerals space for 15 years, the GEOSCAN has been successfully implemented in a wide range of minerals applications including iron, copper, lead-zinc, manganese, phosphate and more, and it caters for the very high demands and increasing requirements of a contemporary processing facility. An area of focus has been on increasing the analysis frequency to allow for rapid analysis results with the same high degree of accuracy typically expected of the GEOSCAN. This paper discusses the underlying research and technology that has enabled such rapid analysis and presents a range of examples using a thorough statistical approach on real production material, demonstrating achievable accuracy over a short analysis time, and dispelling common myths about the speed of the technique. Potential applications are discussed to conclude the paper.INTRODUCTION Technology and the information it can provide plays a critical role in the evolving modern mineral processing landscape. The importance of technology to analyse various features of ores and concentrates being processed is obvious, and recent years has seen the advance of numerous technologies to provide a variety of real-time measurements on conveyed material flows. From sampling apparatus to particle size analysis to weight and density meters to full elemental analysis, the availability of information enables a variety of improvements in the process leading to improved efficiency and increased revenue. To maximise the potential benefits, access to real-time information is imperative, and rapid updates of information become necessary to make appropriate process control decisions based on the most relevant and up-to-date information."

Jan 1, 2017

Carrying Energy ?Energy ?Power, data, signal, hydraulics, pneumatics? ?Needs to be conveyed from a stationary point to a system in motion ?Cable Carriers (steel and plastic), Festoon Systems, Cable Reels and Bus Bars Polymer Cable Carriers ?Life Line for modern machinery ?Transmitting power, data, signal, hydraulics or pneumatic energy ?Constructed and designed to work in harsh environments, at high speeds and to do this continuously ?Meet a wide variety of cable (Media) requirements ?Virtually maintenance free ?High efficiency

Nov 1, 2011

By Lyle F. Smith

With the demand for larger diameter raises under all ground conditions and the increasing price of drill rods and operating costs, it was evident that there was a need for a raise borer with a variable-speed drive and fast-response torque limiting control. The raise boring machine described in this paper was developed after several years of market research and discussions with mine operators and construction contractors. This paper discusses the Ingersoll-Rand raise borers with the solid-state controlled DC motor drives. These machines have gained wide acceptance in the five-year period since being placed in operation and are designed to accommodate the range of raise diameters and lengths most required today.

Jan 1, 1978

By H. B. Sahu, N. M. Mishra, D. C. Panigrahi

The paper presents the development of a spontaneous heating liability index (SHLI) of coal based on a mathematical approach. The parameters for the calculation of this index have been determined by differential scanning calorimetric studies. Thirty-one coal samples representing both fiery and non-fiery coal seams of different ranks have been collected from different Indian coalfields and their SHLI values have been determined. In addition, the susceptibility of these samples to spontaneous combustion has been ascertained by standard crossing-point temperature measurement. The moisture percentage of all the samples has been obtained by proximate analysis. A comparative study between SHLI and crossing-point temperature, along with moisture percentage, indicates that SHLI predicts the proneness of coal to spontaneous heating more accurately.

Jan 1, 2008

By R. B. McIntosh, S Ramanchuk

A brief description is given of the process used by Sherritt Gordon Mines Limited to recover cobalt metal from nickel-cobalt sulphides. A description of the equipment with the operating conditions is presented with an evaluation of the corrosion test results for various stainless steels and other acid resistant materials for the part of the process involving the sulphuric acid leaching of nickel-cobalt sulphide slurry under air pressure. SINCE 1954 the Sherritt Gordon ammonia leach process has been used at Fort Saskatchewan to recover nickel metal, copper sulphides and cobalt-nickel sulphides from nickel concentrate produced at Lynn Lake, Manitoba. 'To develop a process for recovering cobalt and nickel from the cobalt-nickel sulphides, studies were carried out in the Sherritt Gordon laboratory and pilot plant and, late in 1957, continuous acid leaching of sulphides was started in the refinery. In September 1958 the present equipment

Jan 1, 1961

By A. Boeing

Rock-breaker automation and remote operation improves the safety and efficiency of mining operations. This article presents an overview of the Rocklogic rock-breaker automation system architecture that provides collision avoidance, automated parking, and remote operation functionality. The system consists of a distributed computer control system that interfaces with sensors attached to the rock-breaker, the rock-breaker hydraulics, and the site infrastructure. We present results of an automated Transmin rockbreaker installed in a production environment at an underground Australian mine site. The system has been in production use for over 900 days during which there have been no reported collisions, and 100% adoption of the remote operation technology. As a result, Rocklogic has significantly improved the safety of rock-breaking operations and reduced the rock-breaking cycle time, thereby improving the sites overall throughput.

Aug 1, 2013

By G. M. Carr-Harris

"THE SUBJECT of permanent molding has received a great deal of attention in the technical press as illustrated by the many excellent articles in the bibliography which follows. In general, this covers the period 1940-1958 and is merely representative of what is available. Numbers in •brackets refer to items in the bibliography.It may be desirable at the outset to give a few definitions covering those terms directly related to this subject. The following is a definition of permanent-mold casting as given by J. W. Meier in a paper, ""The Non-Ferrous Metals and Alloys"", read before the Ottawa Valley Chapt.er of the American Society for Metals:""Permanent Mold Casting is used where a large number of castings of the same part are required and higher mechanical properties, greater density and closer tolerances are essential. Since metallic mold s are very expensive, the number of castings must be sufficient to, defray, at least partially, the added expense. Molds are usually made from a good quality cast iron, 1but other mold materials, such as the aluminum and copper alloys, graphite, ceramics, etc., are being used in certain cases. Important factors in permanent mold casting are the mold temperature; the proper mold dressing; and, as in all other casting methods, the mold geometry, that is to say, the design of spruces, gates, risers and vents""."

Jan 1, 1960

By B. Konda, R. Lauer, D. Camilucci, D. Gladwin

"Income based taxes are significant cost elements to be considered in evaluating investment in new mine development. This paper presents the results of comparative analysis of effective income-based tax rates for mining in the Northwest Territories (NWT), selected Canadian provinces and international jurisdictions. The study was done as background to a review of royalty regulations for the NWT. ObjectiveThis paper presents results of comparative analysis of effective mining royalty1 rates, and combined effective mining royalty and income tax rates on selected mine models for the Northwest Territories (NWT), with those for several other jurisdictions in Canada and abroad which compete with the NWT for mining investment.BackgroundThe February 27, 1995 federal budget directed the Department of Indian Affairs and Northern Development (DIAND) to proceed with a comprehensive review and amendments to northern natural resource management legislation in order “to increase revenues and ensure a fair return to the Crown.” DIAND is responsible for the administration of the Territorial Lands Act, and its regulations.The Territorial Lands Act gives the Governor-in-Council the authority to “… make regulations for the leasing of mining rights in, under or on territorial lands and the payment of royalties therefor,…”. In the NWT, the Canada Mining Regulations (CMR) provide for the disposition of mineral rights for most minerals, other than coal, petroleum and related hydrocarbons, in return for the payment of a royalty to the Crown.As part of this review of the NWT mining royalty regime, several computer mine models were developed and tax regimes in a number of jurisdictions were analyzed. Effective mining royalty rates, and the combined effective mining royalty and income tax rates were compared across the jurisdictions. The results presented in this paper are a part of the background work done in preparing a discussion paper on proposed changes to the NWT mining royalty that is expected to be released for public consultation in the very near future."

Jan 1, 1997

By Gordon W. Parsons, Ross E. Sampson

"THIS PAPER will trace the work done in bringing the Munro underground ""A"" •Orebody into production to replace the open pit, which was scheduled to be completed early in 1959. Included will be an outline of the exploration work and early planning, and of the final decisions on mining methods. Some of the more detailed work will be described and reasons will be given for the decisions made regarding development work, mine ventilation, ground support, and equipment. Brief mention will be made of open pit operations, as these have had some influence on underground development. Also, some of the main geological features of the ore occurrence will be de-scri0bed, as these had to be taken into consideration when making decisions on ore development and mining methods.LOCATION AND HISTORYhe Munro mine of Canadian Johns-Manville is in Ontario, approximately 50 miles east of Timmins and 40 miles west of the Que-bec-Ontari-0 boundary. The producing orebody is in the southwestern part of Munro township. Property controlled by the Company extends nortl1westerly about 2¥2 miles into Beatty township, on which two other interesting asbestos-bearing zones have been partially expl-0red. Active exploration work on the property was started in March, 194.9, and continued until the summer of 1950."

Jan 1, 1960

By G. S. Farnham

Abstract This paper lists the interests of the Physical Metallurgy and Chemical Research laboratories of the Metallgesellschaft, which were visited by the authors, members of a group of Canadian investigators sent to Germany by the Department of Reconstruction in 1945. The Physical Metallurgy Research Laboratory The following information was obtained from Professor E. Schmid, Chief of the laboratories. It is understood that Dr. Schmid is a former Nazi and was to be removed from his post in November (1945). Aluminium Research The laboratories investigated the corrosion resistance of the high-strength aluminium-magnesium-zinc alloys. The same test procedure as used by V.L.W. was followed and Dr. Schmid co-operated closely with Dr. Brenner on this project. Intercrystalline corrosion was combatted by additions of chromium, titanium, or vanadium, and the work in this field parallels that of Dr. Brenner of V.L.W. * Dr. Schmid reports that Bollenrath and Siebert believe that corrosion difficulties with these alloys can be overcome to some extent by heat treatment. He himself was of opinion that the correct answer lay not only in correct alloying but also in correct heat treatment. The heat treatment involved either interrupted quenching or a change in quenching rate from a solution temperature of 500°C. The procedure is either a slower cooling from solution temperature or an interrupted cooling with a holding period at l50°C. Work had been done on piston alloys, the 11-13% Si, 1% Ni, 1% Cu, and 1% Mg being the favoured material. This is called Lo-Ex and is similar to Mahle 124 or KS1275.

Jan 1, 1946

By Mike Fontaine

The success of a project is defined by meeting the financial performance objectives of the business case within a stipulated timeframe. Early in design, little information is normally available; the uncertainty introduces risk to the project outcome. Using a range of risk management tools and techniques, a project can be developed from front end loading phases 1 through 3 (FEL1–FEL3), and project implementation (FEL4) and then into operations with an optimized probability of success. For every project element, the risk management framework embodies: establishing a context; assessing risk (identify, analyze, and evaluate); and treating risk. Embedded within design activities, this process mitigates or eliminates risks. Monitoring and control, as well as extensive communication and consultation with stakeholders, is integral to the risk management process.

Jan 1, 2015

By A. Plumtree

The morphology of environmentally assisted cracks in stressed pipeline steel has been investigated. For a dilute and neutral solution (NS4) simulating ground water in contact with the steel, semi-elliptical cracks grow faster on the surface (2c) than in the depth (a), hence, the aspect ratio (a/c) decreases. This is explained using a deterministic concept since corrosion is dominant and the primary constraint is the conservation of charge. By contrast, when mechanistic conditions prevail, significant growth occurs in the depth. When underloads are imposed in the loading history, temporary accelerations in crack growth occur because corrosion rather than mechanical effects become dominant.

Jan 1, 2005

The morphology of environmentally assisted cracks in stressed pipeline steel has been investigated, For a dilute and neutral solution (NS4) simulating ground water in contact with the steel, semi-elliptical cracks grow faster on the surface (2c) than in the depth (a), hence, the aspect ratio (a/c) decreases, This is explained using a deterministic concept since corrosion is dominant and the primary constraint is the conservation of charge, By contrast, when mechanistic conditions prevail, significant growth occurs in the depth, When underloads are imposed in the loading history, temporary accelerations in crack growth occur because corrosion rather than mechanical effects become dominant.

Jan 1, 2005

By Olivia Gamache

When working in remote and extreme environments, projects are faced with new challenges for engineering and project execution. This is heightened when also working in countries with a developing environmental regulatory framework, small skilled workforce available for recruitment, and minimal infrastructure such as power, roads, and water. There is an increasing realization that social and environmental aspects need to be built into project execution. Giving proper attention to these issues during project development and execution, and maximizing opportunities is an ongoing challenge.

May 1, 2013