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By S. Rash Ahmadi

Welding is highly reliable and efficient metal joining process. In welding the metal adjacent to the weld joint is subjected to severe thermal conditions. As a result, complex changes in metallurgical structure occur in this region. These changes in structure depend on the material and the temperature history experienced. Friction stir welding (FSW) is relatively a new welding process in which, heat is generated by friction between the tool and the workpiece. The amount of heat conducted into the workpiece determines the quality of weld, residual stress and distortion of the workpiece. The objective of the current work is to study the transient temperature in a friction stir welding. So, a three dimensional transient analytical model is used to study the thermal distribution during the welding. Heat input from the tool shoulder alone is considered in the model. The process parameters like axial load, welding speed and tool rotational speed, used in actual FSW process are taken to build the model. This analytical model is very useful for select the optimized affected parameters in friction stir welding. The model illustrates the comprehensive equation including actual affected parameters in FSW and it can be used for different materials. In addition to the above the thermal history finds application in design of welding tools.

Oct 1, 2011

By Guoxiang Chi

This paper consists of two parts: the first part describes the principles and functionality of the BsnMod program, and the second part presents preliminary application of this program to paleo-fluid flow modeling in the Anticosti Basin. The BsnMod program simulates fluid flow and heat transfer during the evolution of sedimentary basins through numerical solution (finite difference method) of three partial differential equations, which describe sediment compaction, fluid continuity, and heat conservation. It can be used to estimate the evolution of fluid overpressure, flow rate, and temperature during the basin history. The program was written in C++, works under Windows environments, and has a user interface allowing inputs in dialogues and outputs in both tabular and graphic forms. The program was applied to the Lower Paleozoic Anticosti Basin in eastern Canada. The basin history consists of a passive margin stage and a foreland basin stage. Preliminary simulation results indicate that no significant fluid overpressures were developed in the passive margin stage and during the early period of the foreland basin stage, but strong overpressures were developed within the foreland basin succession during the middle and late periods of the foreland basin stage. Fluid flow rates were generally slow, and thermal profiles were not significantly disturbed by fluid movement throughout the basin history. Potential source rocks of hydrocarbons were found in the foreland basin succession. The strong overpressures in the foreland basin succession could have been a major driving force for hydrocarbon migration from the source rocks to the underlying potential reservoir rocks.

May 1, 2001

By J. Illescas, N. C. Murray

This paper provides an economic comparison and technical evaluation of different approaches for copper recovery from small-scale resources such as historic tails, dumps, pond and pit water as well as acid mine/rock drainage. Factors such as the location, the availability and cost of reagents, power availability and cost and a local market for end product alter the preferred processing technique. A number of scenarios are presented and technologies considered include; solvent extraction, ion exchange, sulphide precipitation, cementation, copper sulphate crystallization, membrane (RO) and copper cathode production.

Jan 1, 2014

By Ken Steele, Pam Sangster, Myra Gerow

Ontario leads Canada in production of structural materials and ranks third in production of non-metallic minerals. The total value of industrial mineral production in 1997 was $1.6 billion. The province is the leading producer of nepheline syenite, salt, talc, clay products, cement, lime, sand and gravel, stone and a major producer of gypsum and silica. Barite, sulphur in smelter gas, elemental sulphur, tremolite, serpentine, gemstones and peat are also produced. Table 1 shows recent actual industrial mineral production levels in Ontario. Other industrial minerals, including phosphate, petalite, diamonds, wollastonite, vermiculite, kyanite, garnet, graphite, silica, kaolin, dimension stone and anorthosite, have been the target of exploration and development projects. Investment opportunities exist at all levels from grass-root prospect through to production level.

Jan 1, 2001

By Joseph W. Mills

"The Mic Mac property comprises 994 acres held under mining concession and approximately 2,000 acres held under development licenses in Bousquet township, Abitibi county, western Quebec.Gold was first discovered in this locality by Tom Duval in June, 1936. In February, 1937, Cassels Duval Mines, Limited, was incorporated under Quebec charter to take over the property. In September, 1937, the property was examined by Agaura Explorations, Limited, and an option agreement was signed on October 6th, 1937. In June, 1938, an option for complete ownership was taken on adjoining claims belonging to Norgold Mines, Limited, and in September, 1938, a mining plant was installed and the sinking of a 3-compartment shaft begun. In June, 1939, an option was taken by Mic Mac Explorations, Limited, on seven claims of Mooshla Gold Mines Company, Limited, that adjoined the Norgold block to the east. In December, 1939, a new company, Mic Mac Mines, Limited, was formed, amalgamating the Cassels Duval, Norgold, and Mooshla claims, as well as two claim groups to the west of the mine known as the Vaughan and West Cassels groups."

Jan 1, 1954

By Phillip Mackey, Elmira Moosavi-Khoonsari

L'industrie du cuivre traverse une période passionnante, marquée par une forte demande, de bons prix et l'ouverture de nouvelles grandes installations. L'année 2022 a battu des records de production de cuivre, ce qui laisse entrevoir un potentiel de croissance supplémentaire. De grands projets sont en cours, comme la technologie Double Flash à Manyar, en Indonésie, qui peut produire plus de 500 000 tonnes de cuivre par an. À Munda, en Inde, on a construit la plus grande usine de cuivre du monde, qui produit plus de 1 000 000 tonnes de cuivre par an en combinant deux phases. De plus, l’installation de cellules de flottation de dernière génération au Mexique, au Chili et dans d'autres pays témoignent de la volonté de l'entreprise d'utiliser les technologies les plus récentes [1]. L'importance du cuivre dans la transition énergétique est évidente, l'accent étant mis à la fois sur la croissance et sur la protection de l'environnement. Cela se traduit par le développement d'usines de premier ordre dédiées aux pratiques durables.

May 2, 2024

By J. Beland

The Rimouski-Matapedia region is along the southwestern extension of the central Siluro-Devonian synclinorium of Gaspe Peninsula. As in Gaspe about 30,000 feet of Siluro-Devonian strata rest on a "basement" of tightly folded Ordovician rocks. The central synclinorium is divided up into two northeasterly trending belts each of which is characterized by distinctive lithologies and patterns of folding. The northwestern belt is gently to moderately folded and includes lithologies which point to a stable environment. The southeastern belt on the other hand is tightly folded and the lithologies indicate a less stable environment. A marked angular unconformity separates the basement from the Siluro-Devonian cover near the north-western margin of the northwestern belt. At the southeastern margin of the southeastern belt the relationship of cover to basement has not been as-certained because of a fault. The northwestern belt has several features significant in the search for petroleum; the Silurian strata are exposed in broad open anticlines

Jan 1, 1962

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 R. F. Baxter, C. M. Read, R. I. McCulloch

"Globalization of the aluminium industry continues to increase the pace of change and the intensity of competition, while simultaneously, society demands better products, cleaner technologies and sustainable industries. Bechtel, a global engineering, construction and project management company, is not immune to either the opportunities or the challenges created by globalization. However, and not withstanding the challenges, for aluminium industry ""players"" with a true global perspective, globalization presents very real opportunities that may be leveraged to deliver value creating goods and services. The following paper will focus on the exploitation of one of the opportunities created by globalization in the Knowledge Management domain - the application of high level tools and methodologies to improve global delivery of greenfield and brownfield aluminium smelter construction projects. Specific examples will be presented of value driven solutions that were delivered at the early stages of project engineering."

Jan 1, 2006

By J. M. Wetherill

"This paper presents the results of an investigation into the level of radon, as against the natural background, at the Vicary Creek coal mine in Alberta. The concentrations of radon and daughter products detected in the mine were considered to be insignificantly higher than the concentrations of naturally occurring radon and thus do not constitute a health hazard to the miners.INTRODUCTIONTHE HIGH INCIDENCE OF LUNG CANCER among miners exposed to radon was established some thirty years ago. The presence of this gas in mines is primarily associated with pitchblende extraction operations, al-though coal contains detectab`e quantities of U30s. A previous study bas shown that coal from southwestern Alberta (Exshaw and Banff) contains lower than average concentrations of this element (1).As part of a general investigation into the occupational health environment of coal miners in Alberta, field measurements were made to establish the level of radon and to investigate the natural background radiation in the Vicary Creek coal mine, located some 16 miles north of Coleman, Alberta, on the easternmost slopes of the Rocky Mountains."

Jan 1, 1968

By B. Daniels, A. Tieu, W. Yan, B. Ren, M. Vijay

"Plasma or thermal sprayed coatings are becoming more widely used in a wide range of industrial applications. The preference to use thermal sprayed coatings is mainly attributed to its superior wear, and corrosion resistant properties akin to hard chrome but without the harmful health implications of chrome in the coating process. Specifically, High Velocity Oxygen Fuel (HVOF) plasma sprayed Tungsten Carbide & Cobalt (WC/Co) coatings are presently being tested on aircraft landing gear. This coating can be efficiently applied and is highly resistant to corrosion and wear. However, HVOF coating's durability also makes it difficult to be stripped for inspection and overhaul. Current coating removal methods usually involve a multi-step process whereby the coating must undergo diamond wheel grinding, chemical dipping, grit blasting, ultrahigh pressure (UHP) 380 MPa (55 Kpsi) water blasting, and subsequent chemical dipping, depending on the type and thickness of the coating. As explained by Yan, et al [l]"" a unique method has been developed for removing HVOF coatings with the use of only water. The method consists of modulating a stream of water at a pressure of only 69 MPa (10 Kpsi) with ultrasonic waves to generate a forced pulsed waterjet. The resulting cyclic loading of the hard coating due to the impact of the water pulses easily causes it to flake off the substrate. This paper will briefly describe the fundamentals of the forced pulsed waterjet technique with an emphasis on insitu applications of the removal of various plasma and HVOF coatings."

Jan 1, 2006

By Dallas W. Davis

Twin - Kennecott Deal Announced April 15, 2004 ! Kennecott earns 56% interest, if in 4 years, spends C$10 million and recovers at least 200 cts of +1 mm diamonds in all dimensions from any contiguous body ! Earn-in can take up to 6 years, but incurs stepped reduction of interest from 56% to 46% or 0% if $C10 and 200 carats not achieved ! By funding all costs through feasibility study, Kennecott earns 71% in 7 years, or, stepped reduction to 62% if completed after 8 years ! By achieving production within 10 years and funding Twin?s share of development and construction costs, Kennecott earns further 4% ! If no election to develop a mine within 2 years of feasibility study completion, Twin may present development proposal which Kennecott has 60 days to elect to follow or transfer management to Twin and dilute to 49% ! Each party has one time right to elect to market its diamond share ! On signing and annually, Kennecott will purchase $C250,000 of Twin shares at 130% of then prevailing market price until achieved earn-in

May 1, 2004

Keeping the sediment on the mine site and out of the water course is essential from the regulatory, environmental and sustainability perspectives. Regulation of this aspect of mining is embedded in environmental legislation and government receiving water quality standards, and government control has apparently been considered to be the most appropriate method to define mine site discharge standards and the environmental implications of sediment in downstream watercourses. A literature search for guidelines for the site specific design and operation of sediment ponds treating mine site runoff to remove total suspended solids, turbidity and flocculant-induced toxicity, revealed little information on the mining industry?s and government?s roles in defining the ?how to achieve? related to sediment pond design. Is there a need or reason for an industry-driven leadership to clearly define the ?how to? keep the sediment on the mine site and out of the water course? Currently, this issue is addressed in Canada by a federal mining regulation for metal mines which specifies discharge quality for sediment. This paper focuses on the method used in British Columbia, Canada, to regulate and provide a scientific methodology to control the discharge of sediment from mine sites. Management plans relative to this topic are discussed and are considered to have value from the exploration, construction, operation and the onset of closure phases. In addition, the balance and linkage between the erosion control management plan and the sediment pond management plan are discussed in terms of how they may be designed to complement each other to lower the risk of exceeding discharge and receiving water quality standards. If there were an industry-driven standard, or guidance document relative to addressing sediment release, it would benefit mining companies by eliminating the repetitive analysis of this topic for each new mine, mine expansion, and mine modification; also, government may often replace certain aspects of permitting with a regulation, if there is a government/industry established standard defining Best Achievable Technology (e.g. the Canadian Metal Mining Effluent Regulations).

Aug 1, 2013

By Du Xinfeng

The resource quantity of the low rank coalbed methane (CBM) accounts for 47% of the total resource quantity of CBM in China. Compared with the exploration and development of the high rank CBM in Qinshui Basin, China and the low rank CBM in Powder River Basin, USA and Albert Basin, Canada, the exploration and development of the low rank CBM are still in the initial test stage. In this paper, on the basis of analyzing the mining geological conditions such as that the Huanglong Jurassic Coalfield is largely situated in the hills and gullies zones, and the coal reservoir has the features such as the low metamorphic degree, large coal seam thickness, simple coal matrix texture, high permeability and small CBM content and so on, it discusses the key technologies such as the development pattern of CBM, well location arrangement, drilling and well completion technology and fracturing technology and so on. It indicates that the underbalanced drilling and the cavity well completion based on the reservoir protection will be the development directions of the CBM development technology in this area.

Aug 1, 2013

By R. R. Montigny

A brief description is given of the history, location and geology of the Granisle Copper Limited operation on Copper I land in Babine Lake. Detailed information is given with regard to pit design, planning, drilling, blasting, excavation and haulage. Equipment maintenance and mining costs are also presented.

Jan 1, 1971

By F. W. Gray

Ideal utilization of the heat energy in coal should theoretically be secured by supplying each atom of combustible material present with the exact quantity of oxygen necessary for complete combination. An intimate and equal admixture of the fuel particles with air is therefore to be sought. Coal, or the combustible substances of which coal is composed, may be used in solid or liquid or gaseous form. The use of coal in small particles intimately mixed with air is, in effect, a specification of coal in pulverized or dust form. There has been much important development of this manner of using coal, which may be instanced as the outstanding advance in the use of coal as a solid. The completeness and efficiency of combustion in a properly designed dust-fired furnace permits the use of locally available coals of inferior quality, and enables them to be used commercially instead of imported coals of better quality. That is to say, some grades of coal of low calorific value, that are not economically useable in lump form on grates, are useable in pulverised form, because of the more complete combustion thereby obtained, and the consequent more efficient results. In the case of coals that are unsuitable for steam-raising in grate-fired furnaces, because of clinker troubles, (arising usually from a combination of high sulphur content and low-temperature fusibility of the ash content) use in pulverised form has obvious advantages, and in addition gives the benefit of any heat units that are contributed by free sulphur in the coal.

Jan 1, 1924

By George W. Bain

The area in Quebec immediately north of the Ottawa river is underlain by a large area of granite gneiss intruded in lit-par-lit fashion into Grenville sediments and low silica intrusives of the Buckingham Series. This complex of metamorphic rocks is intruded by a much later magma found, chiefly, as a very large stock about 20 miles in diameter and extending from Brownsburg to Grenville, and as dykes and small outliers at various places adjacent to its outer margin. 1A similar stock at Rigaud, Quebec, is situated south of the Ottawa river and has been described by O. E. Le Roy. The earliest representatives of the later magma are a series of granodiorite dykes characterized by abundant hornblende, along with primary magnetite and subordinate sulphides scattered as roundish grains through anorthoclase and aligoclase feldspars and subordinate quartz. The rock is found as narrow dykes and shows no prominent secondary structures, either in the field or in thin sections under the microscope.

Jan 1, 1926

By A. Ghahreman, M. Oliazadeh

"Heap leaching is an attractive process for low grade deposits where the metal content of ore does not justify the high cost of milling and agitated leaching. In general, the heap leaching capital cost is low, construction is rapid, and production costs are low. The primary disadvantage of heap leaching is low recoveries (typically 65% of agitated leach recovery); thus, recovery improvements could convert more lower-grade deposits into minable reserves. This will also allow to process primary sulfide ores and result in a dramatic expansion of the technology, as ~80% of total ore types are sulfidic in nature. The old gold operations tailings are another massive source of low-grade gold material that can be retreated by the heap leach process. The major parameters affecting the recovery rates are ore characteristics (mineralogy, particles size of metal and host minerals, ore permeability), and operational conditions (segregation of ore, compaction, leach cycle time, lift height, and solution application rates). The design of a percolation leach process is based on a limited number of coarse ore bottle roll and/or column tests under ideal conditions. The economics of the projects and engineering design of the process facilities are developed based on the bench scale test work results and the application of the conventional engineering scale up factors. This paper will deal with the parameters affecting the HL efficiencies and focus on the potential improvement of gold heap leach recoveries. This would include design of heap leach operation and evaluation of processes such as fine crushing and bioleaching.INTRODUCTION Gold heap leaching is a hydrometallurgical process designed to treat amenable low-grade gold ores that contain typically 0.5 to 1.5 g/t gold (Marsden and House, 2006; Wong Wai Leong and Mujumdar, 2010). Ore is stacked by various types of equipment on an impermeable barrier, and a sodium cyanide solution is applied to the surface of the stacked ore. Gold, silver, and other metals contained in the ore are dissolved to various degrees by the cyanide application, as it percolates downward through the stack of the ore. The pregnant leach solution (PLS) is then collected at the bottom of the heap. The PLS is then sent to the gold recovery plant where the metals are extracted. The barren leach solution (BLS) is then reapplied to the top of the pad. Ore is placed on a pad or previously leached lift by various means, including ramp conveyor belts, radial-arm and self-leveling stackers, and trucks. Once trucks are used to construct the pads, the pad can be compacted and hence the pad should be graded and ripped or scarified (roughened up) with wheeled or tracked equipment to produce shallow cuts to increase surface area exposure to the leachate."

Jan 1, 2019

By R Chandramohan

Comminution is the science of size reduction of brittle materials. It is integral to mineral extraction and is one of the most energy intensive processes in the mining industry. There are a number of tests used to quantify the strength of ore, which are then used to size the AG / SAG mill in circuit design. The calculated energy utilized for breakage in these devices is based on the assumptions that the materials treated are of average shape and that the processing equipment is designed to break the ore as efficiently as possible under the given operating conditions. In drop weight tests, it was found that shape significantly influences the measured rock strength. Controlled experiments with variations in blends of rock shape show that mill throughput increases with the addition of weaker shaped rocks.

Jan 1, 2012

By André Chagnon, Héroux. Yvon

"Résumé - Cette étude porte sur l'altération de la matière organique et des argiles dans les boues carbonatés dévoniennes du facies ""F' de la Formation de Pine Point et ses équivalents stratigraphiques la Formation d'Evie et l'unité bitumineuse de la base de la Fonnation de Hom River. La matière organique se compose principalement de bituré solide et de quelques fragments de fossiles (organaclastes). La majorité des échantillons ne renfement que de l'illite et des inter-stratifiées illite/smectite.Si on compare les températures d'homogénéisation (Th = 100°C) des inclusions fluides de la sphalérite et des dolomites associées a la minéralisation aux températures estimées à partir de la réflectance de la collinite (84°C à 117°C), l'on ne peut pas conclure à la présence d'une anomalie thermique dans le district minier de Pine Point. De plus, la réflectance des organoclastes n'est pas plus élevée dans le district minier de Pine Point que dans les localités plus éloignées des gites. L'analyse des minéraux argileux conduit à la même conclusion: aucune anomalie thermique n'est décelable dans les unités échantillonnées à l'intérieur du district minier de Pine Point quelque soit l'indicateur utilisé.La kaolinite et la matière organique altérée, affichant des valeurs anomales de sa réflectance, se trouve essentiellement en présence de soufre et de sulfures. Cela suggère une origine authigène de la kaolinite et une altération de la matière organique reliées au phénomènes de minéralisation.Abstract - The alteration of organic matter and clays is studied in the Devonian Pine Point Formation carbonate muds, ""F"" facies, and its lateral equivalents the Evie Formation and the bituminous unit at the base of the Hom River Formation. The organic matter is mainly composed of solid bitumen with few fossil fragments (organoclasts). Most samples contain only illite and mixed layer illite/smectite.If we compare the Th (100°C) from fluid inclusions of sphalerite and dolomites associated with mineralization to the temperatures calculated from the reflectance (Ro) of the collinite (84°C to 117°C), we cannot detect a thermal anomaly in the Pine Point mining district. This result is based on the reflectance values of organoclasts from the mining district that are not higher than those reflectance values measured on organic matter (OM) away from the ore deposit. A similar conclusion is reached from the clay study: none of the parameters used allow us to identify a thermal anomaly in the samples from the mining district.The kaolinite and the altered OM showing anomalous Ro values mainly occur with sulfides and sulfur. This association suggests an authigenic origin for the kaolinite and an alteration of the OM due to the mineralization events."

Jan 1, 1994