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By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005

By Claudia Gasparrini

"Factors affecting the extraction of gold are of a mineralogical nature. Knowledge of the mineralogy of the ore or metallurgical product to be treated, if appropriately combined with the metallurgical test work, may improve gold recoveries. .This paper outlines the mineralogical techniques f or the study of gold ores and metallurgical products and describes the gold mineralogy in relation to its metallurgy. An effective plan for studying refractory and other difficult ores, combining metallurgical test work, chemical analysis and mineralogy and capable of giving positive results over relatively short periods of time, is suggested.IntroductionFactors affecting gold recoveries are of a mineralogical nature and include (i) the gold-bearing minerals, (ii) their grain size and, particularly where the grain size is very fine (10 microns in diameter and less), (iii) their host minerals and (iv) the association these form with the gold-bearing minerals.Mineralogical studies of gold ores and metallurgical products containing gold in economic amounts (today down to 1/10 of one ounce per tonne or 2.84 ppm) are difficult and time consuming. Mostly because of such reason, metallurgical testing (test work) is usually done simply by trial and error without understanding the causes for failure or success.Mineralogical studies, if appropriately conducted and combined with the test work, provide an efficient mean s of improving recoveries through the understanding of gold losses derived from the use of the wrong technique for separation. The information they provide is therefore the first step in the development of recovery techniques, for those ores where the test work alone failed to produce positive results."

Jan 1, 1983

By K. R. Brown, P. L. Krawchuk

In-situ recovery (ISR) is under increased investigation as a viable methodology for the extraction of minerals in ore bodies that may be uneconomic to mine by traditional methods or for resources situated in locations where underground and surface mining operations are not feasible. Although the concept of ISR is relatively new with respect to hard rock applications, it is not a new technology; it has been used successfully in potash and uranium mining and also in heavy oil extraction for years where it has been proven to be both technically and commercially viable. ISR allows for the extraction of metals and minerals without the need to mine large amounts of ore that need to be processed at surface. The ore stays in-situ and only the valuable metals and minerals are produced to surface in a process that produces very little to no waste rock or tailings. This paper aims to discuss the geological conditions that make ISR amenable to an ore body as well as the application of maturing technologies such as advanced directional drilling and the creation of artificial permeability that will help to access deep ore bodies and enhance or create favorable recovery conditions for ISR in the ore body. INTRODUCTION In-situ recovery (ISR), also referred to as in-situ leaching, is a potentially disruptive technology for the mining industry. ISR is under increased investigation as a viable methodology for the extraction of valuable minerals that may be uneconomic to mine by traditional methods or for deposits situated in locations where underground and surface mining operations are not feasible. Although the concept of ISR is relatively new with respect to hard rock applications, it is not a new technology; it has been used successfully in potash mining, uranium mining and also in heavy oil extraction for years where it has been proven to be both technically and commercially viable. Recently there has been increased interest in deploying ISR in hard rock applications due to a number of factors: the drive for environmental stewardship is stronger than ever, technological advances in drilling, blasting, and leaching are strengthening ISR economics, and a large inventory of ore bodies exists that are not feasible to mine or extract using conventional open pit or underground mining techniques. ISR allows for the extraction of valuable metals and minerals without the need to mine large amounts of ore that need to be processed at surface. The ore stays in-situ and only the valuable metals and minerals are produced to surface in solution via a recovery process that produces very little to no waste rock or tailings. Where the right conditions exist, the ISR process has a much smaller environmental footprint (Hiam-Galvez, 2018) and potentially much lower capital and operating costs than using conventional mining techniques.

Jan 1, 2019

By F. Parada, R. Parra

"The neutralization process of SO2 from coal burning plants is a well-defined technology using limestone to form CaSO4 according to the following reaction: CaCO3 + SO2(g) + 1/2O2(g) = CaSO4 This paper presents the results of a study carried out to validate the option of capturing SO2 using gases from a non-ferrous smelter; SO2 content was up to 12% using a three-stage fluidized bed reactor. The difference in SO2 content affects equilibrium conditions and kinetics, rendering a direct extrapolation of the high efficiency achieved for low SO2 content impossible. The R&D program consisted of a laboratory study using a semi-pilot operation of a one-stage fluidized bed reactor and the construction and operation of a three-step reactor prototype. Results show that the reaction proceeds according to the unreacted core model that imposes a compromise between CaCO3 conversion and SO2 capture. For high SO2 capture, the calcine from the reactor contained CaSO4 and CaO. A complete capture of SO2 from gases with 8 vol.% can be achieved with a mean reaction time of two hours at 800°C."

Jan 1, 2007

"Mining with blast holes drilled upwards may be done to recover sill pillars, or for economic reasons when the distance between the levels is relatively large. If the rock is sufficiently competent to accommodate large stope size, the distance between sublevels could be increased to as much as drilling accuracy allows. The same drill drift can be used for the drilling of both down holes and up holes. In the case of down holes, the initial opening of the stope (drop raise) is not as much a problem as for the inverse drop raise for mining with up holes. This is because, with a drop raise, a lot of space is available at the toe for the blasted rock to expand. In addition, the raise can be blasted in many shots, thus allowing smaller blasts each time. Inverse drop raises are generally much more difficult to blast because of the limited space for muck flow, and must, therefore, be taken down in a single blast, requiring special considerations in order to ensure a success. A case study of a 29 m (95 ft) inverse drop raise successfully blasted in a single shot at Heath Steele Mines is described. The paper covers technical considerations such as drilling accuracy, hole deviation survey, delay extension and protection, initiation methods and initiation sequence. Finally, a novel method for creating the initial opening called ’slot drilling’ is presented. This method, inspired from LKAB in Sweden, consists of drilling a row of interconnected holes using a special guide mounted on a regular production drill hammer.With a case study of blasting an inverse drop raise of 29 m (95 ft) in one blast, this paper further discusses some technical issues that are critical for the development of inverse drop raises. A novel method for creating the initial opening with a slot of interconnected holes is also presented with the experience acquired at different mine sites across the Noranda group."

Jan 1, 2000

By Adrian E. Scheidegger

"AbstractThe possibilities of deriving pertinent information about fractures in an oil pay from data obtained by core analysis are investigated. It is shown that it is possible to obtain an estimate of the fractured area per unit volume of the pay, and that the size of the fractures can be estimated if their shape is known. A suggestion of a routine procedure for the analysis of fractures is given.1.-IntroductionMany oil fields are producing essentially from cracks or fractures. Where this is the case, it is important to be able to obtain a knowledge of the size and distribution of those fractures in the oil pay. This knowledge has to be derived from the analysis of cores taken from the fields, as it is generally impossible to follow a fracture through the pay by direct means. The necessity of using statistical methods to extrapolate the meagre information obtained from the cores of the wells is therefore indicated.It is known that the fractures are much bigger than the diameter of the cores; thus, if they strike a core, the latter will generally fall into two pieces. The angle of the fracture with the vertical can be measured and, if oriented cores are taken, the exact position of the surface element representing the intersection of the fracture with the drill stem can be determined. Sometimes the edge of a fracture can be seen in a core. The number of •Cores that show such an edge can be noted. Of course, one has to be careful to distinguish between original fractures in the pay and fractures in the core caused by drilling operations. Only the former are relevant."

Jan 1, 1955

By L. J. Han, Y. J. Zong, S. Y. Wen, J. J. Wei

"Stress strain curves characteristics, deformation and strength properties, and failure process and characteristics of sandstone samples under different stress states were analyzed through triaxial compression tests carried on using TAW-2000 microcomputer control electro-hydraulic servo rock triaxial test system. The experimental results reveal that peak strength, residual strength, elasticity modulus and deformation modulus increase linearly with confining pressure, and failure models transform from fragile failure under low confining pressure to ductility failure under high confining pressure. Macroscopic failure forms of samples under uniaxial compression was split failure paralleling to the axis of samples, while macroscopic failure forms under uniaxial compression was shear failure, the shear failure angle of which decreased linearly with confining pressure. There were significant volume dilatation properties in the loading process of sandstone under different confining pressure, and then based on acoustic emission damage and volumetric dilatation damage the damage evolution properties of samples were analyzed, and damage constitutive model were established, realizing the real-time quantitative evaluation of samples damage state in loading process. INTRODUCTIONDamage is a phenomenon that micro defects in material under monotonic loading or reloading will lead to progressive decrease of the cohesion and damage of volume units. Many scholars at home and abroad have carried out systematic researchers on damage evolution characteristics and constitutive model of rock, and have achieved a series of remarkable results in this field. Lu Y.D. (2004) studied the complete stress-strain curve’s characteristics of marble under triaxial compression, and established the bilinear elastic-linear strain softening-residual ideal plastic damage constitutive model. Ren J.X. (2001) studied the damage evolution laws of coal and rock mass by computerized tomography triaxial loading system, realizing the quantitative evaluation of damage state. Zhang Z.L. (2011) studied the deformation and failure mechanism of strong weathered sandstone by triaxial compression test, and analyzed the damage evolution processes and established the damage evolution equations based on the density method. Li X.J. (2012) studied the microscopic damage characteristics of siltstone under triaxial compression by scanning electron microscope and digital image technology, and analyzed the statistical distribution characteristics of cracks azimuth angle, length, width. Zhou J.W. (2012) studied the strength, deformation and fracture damage characteristics of sandstone by uniaxial cyclic loading and unloading tests, and defined damage variable based on linear damage mechanics theory and acoustic emission (AE). Cao W.G. (2006) established a new damage model and a statistical damage constitutive model of rock under specific confining pressure according to the force of damaged part and undamaged part in rock on the base of statistical damage theory. Li S.C. (2014) studied the damage evolution characteristics in the whole uniaxial compression process of sandstone by electrical resistivity and AE, and proposed a status qualitative criterion for rock damage."

Jan 1, 2015

By G. C. Lipsyy

ALL mineral production? of Can11.da is transported in a mine car at some stage during its extraction. There are as many types and varieties of mine cars as there are of mines. Many of the cars in use were developed in the blacksmith shop. Others were designed by engineers and improved by the mine foremen and the mechanics. Every mine car has the ideas of miner, blacksmith, mechanic, and engineer incorporated in it. Many of these ideas are not generally known. This paper was written to make at least some of this information available to the mining industry. In drawings, tables, and notes, it gives all the important details pertaining to the cars. It .does not recommend any particular type of car for any particular piece of work, nor does it present drawings from which a car can be built. It gives the engineer or master mechanic information on many cars which he can apply to his own particular problems. It is hoped that this information will be of use to mine operators. If a few new ideas are conceived as a result of the paper, the author will feel that the effort of compiling it has been worth while. In order to obtain the data for the preparation of the paper, a questionnaire, copy of which is here reproduced, was sent to all the operating mining companies in Canada. An accompanying letter briefly explained the purpose of the paper and asked for co-operation in furnishing as complete information as possible.

Jan 1, 1945

By N. Erarslan, M. Ghamgosar

With the increased use of mechanized rock excavation, there have been developed internationally a number of methods to assess the abrasivity of rock materials. These methods range from determination of abrasive and hard mineral content using petrographic thin section analysis to weight loss or rate of wear flat development on specified test pieces. The Cerchar abrasivity index (CAI) test has been widely accepted for the assessment of rock abrasiveness and is determined as the abrasion of a steel pin after scratching over the freshly-broken or saw-cut surface of a rock. Two types of testing devices are in use today: (i) the original ‘Cerchar apparatus’, and (ii) the ‘West apparatus’, which was adopted herein. The CAI is calculated from the measured diameter of the resulting wear flat on the steel pin after 10mm scratching. This test has been considered to provide a reliable indication of rock abrasiveness for isotropic rocks. However, a great amount of rocks in natureis anisotropic. Phyllite is an anisotropic and foliated metamorphic rock and various types of phyllite specimens were tested in this research. Although phyllite is a type of rock primarily composed of quartz and the expected CAI value can be high, mechanical cutting of this rock should not be very problematic compared with igneous rocks have same CAI value. As phyllite is a foliated metamorphic rock, most of the specimens split into sheets through the quartz seam by the tip during scratching normal to the axis of quartz seams. Hence, viability assessment of Cerchar abrasivity test and F-Schimazek index values for the anisotropic rocks is investigated in this research.

Jan 1, 2015

By S M. Roscoe

Relationships of Noranda sulphide deposits to volcanic rocks are reviewed and chemical variations within the volcanic sequence are described. The assemblages of minor elements in the pyrites and pyrrhotites of the Noranda and l\llatagami deposits are similar and are characterized by a high content of cobalt, tin and other elements. Isotopic compositions of lead, other geochronological data and stratigraphically disposed zonal distributions of sulphides and minor elements indicate that the deposits were formed prior to folding and metamorphism. Lead isotope data indicate that the Matagami deposits, and several others, were probably formed about 2.95 x 109 years ago and that the Noranda deposits may be about 50 million years younger. The volcanic sequence at Noranda is younger than the thick sequences bordering it on the east and on the west. The relationships are consistent with the hypothesis that these strata-bound sul1>hide de-posits are coeval with their associated volcanic rocks. T HE writer has been engaged in a metallogenic study of the region between Sault Ste. Marie and Chibougamau. An essential objective of this study is the classification of mineral deposits with regard to their composition, form, geological

Jan 1, 1965

By J. S. Fox

"Besshi-type Cu-Zn (-Ag-A u ± Co) deposits are tabular, stratiform volcanogenic sulphide bodies which are usually associated with mafic volcanic rocks of oceanic or intra-plate geochemistry, but which can also be found locally with ultramafic volcanics or subvolcanic mafic intrusions. A thick sequence of continentally-derived clastic sediment usually encloses both the mafic volcanics and the ore. Besshi-type deposits form subaqueously, in epicratonic rifting environments, more-or-less proximally, and as a result of hydrothermal convection in their subjacent mafic volcanic - clastic sedimentary piles. They belong to a rift -related metallogenic spectrum that includes sediment-hosted and Cyprus-type base metal deposits, and may diller genetically from these mainly with respect to rate and degree of crustal extension. Modern analogues to these deposits are f ound in the submarine volcanogenic sinters of the Gulf of California rift system.The associated lithologies and tectonic selling of Besshi-type deposits clearly distinguish them from Kuroko-type ores. This difference also seems to be reflected in their lead isotopic character. For example, leads from Besshi-type deposits in the Sanbagawa belt of Japan and from the Blue Ridge belt of southeastern U.S.A. lie on extended anomalous lead lines and have lowslopes in 207Pb/204 Pb - 206Pb/ 204 Pbspace (Sato and Sasaki, 1980; Leriuray, 1982), wheras those from most Kurokotype mining districts exhibit only narrow isotopic ranges and lie near or on the orogene growth curve (e.g. , Franklin et a I., 1981). More over, where Besshi- and Kuroko-type deposits are found in the same orogene, the former often occur earlier in the tectonic cycle than the tatter (e.g., Japan, the Norwegian Caledonides, the southern Appalachians and south-central Finland).Besshi-type deposits are not confined to any particular part of the world, or to any geological epoch. Moreover, in many mineralized belts, Besshi-type deposits are the predominant volcanogenic ore type. On a world-wide scale, deposits of this type therefore constitute an important base metal resource."

Jan 1, 1984

By John Drew Ridge

"Over the years, ore geologists have made innumerable observations as to the relationships of certain kinds of ore deposits to particular types of rocks and to the types of primary and secondary structures that these rocks contain. On the basis of these, the places in which to look for new are deposits are more clearly defined than they would be in an exploration program based largely or solely on concepts of ore genesis. This paper discusses the affinity of certain rock types and structures for such ore deposits as: (1) tin-tungsten associated with granitoid rocks; (2) lead-zinc of simple mineralogy in carbonate rocks; (3) massive base-metal sulphides in sedimentary or volcanic rocks; (4) massive base-metal sulphides and oxides at, or near, contacts with igneous rocks; (5) gold or gold-uranium in, or adjacent to, conglomerates; (6) shale- or sandstone-hosted copper; and (7) porphyry coppers. Additional varieties could be considered, but it appears that these examples are sufficient to demonstrate the validity of the suggestion that the use of observational characteristics is far more useful in mineral exploration than that of theories of ore genesis.As by-products of the theory of plate tectonics, many concepts have been put forward to explain how ore deposits of different kinds have been formed. Most, if not all, of these theories seem to be as valid as present-day information permits. However, do these ideas add to the ability of the ore geologist to find ore deposits? I doubt it, and offer reasons as to why I think so.To produce maximum results in any exploration program, the one that makes the greatest use of information produced about the geologic environment of the area being investigated is the one that will provide the greatest return in deposits found for the sponsors of the program. Such exploration is best designated as total exploration, and it certainly is the most effective way of uncovering such new deposits as may exist in the area being studied in particular and of adding to the sum total of nonfuel minerals deposits available to the industrial world in general."

Jan 1, 1983

By M. S. Badollet

"The study of the physical properties of asbestos minerals requires a careful isolation of the fiber from the wall rock and, at a later stage, a comparison of these physical properties with those of fibers that have passed through the milling and beneficiation processes.The effects of mineral impurities, loss of fiber length and the formation of extreme fines (asbestic and/or associated minerals) often show up in the formation of special asbestos products as well as in the commercial production of asbestos papers, mill-boards, asbestos cement products, plastics and insulation materials, and in the filtration of blood plasma and wines.Numerous test methods have been developed in Canada and in England for use in the asbestos industry. Special treatments of asbestos fibers have been used to improve their physical and chemical properties and to eliminate impurities.Numerous problems connected with the use of asbestos fibers are discussed, such as the effects of asbestos on filtration, surface area, surface treatments using organic or inorganic materials, the surface charge on the fiber, the presence of magnetite and air pollution elimination. Biological studies on finely ground asbestos, when dispersed in 0.9 per cent sodium chloride solution and then sterilized and injected into hamsters, show that by reducing the dose, the tissue damage can be largely avoided. In these experiments, Arizona asbestos fibers were carefully extracted from the wall rock, finely ground, and examined chemically and micros-copically for any mineral impurities that might be present so that any effect on the hamsters would be directly due to the presence of the asbestos. The harsh Arizona fiber induced more extensive tissue response than the soft fiber when tested in hamsters."

Jan 1, 1969

By G. Roy, D. R. Lentz, A. O. Wills

"Abstract - Diamond-drill hole DDH-B357, located 1.5 km north of the Brunswick No. 6 Zn-Pb- Cu-Ag volcanic-sediment-hosted massive sulfide (VSHMS) deposit, intersects three exhalative horizons within variably altered felsic volcanic rocks of the Nepisiguit Falls and Flat Landing Brook formations. These three petrographically indistinguishable iron formation intervals (Fe2O3T = 21.4 wt.%) likely represent cogenetic hydrothermal sedimentary units because they display a common geochemical signature: Fe2O3T = 42.9 ± 10.5 wt.%, MnO = 5.4 ± 3.1 wt.%, elevated base metal values (Zn+Pb = 1999 ± 1091 ppm), strong enrichment in additional exhalative components (CaO = 5.3 ± 3.9 wt.%; P2O5 = 1.43 ± 1.00 wt.%), oxidized signature (Fe/Mn = 10 ± 6), as well as a common immobile element signature (Zr/TiO2 = 0.025 ± 0.007) representative of a pelagic source. The calc-alkaline to transitional host volcanic rocks can be discriminated by Zr/TiO2, and to a lesser extent by Th/Nb: Nepisiguit Falls Formation: Zr/TiO2 = 0.053 ± 0.004, Th/Nb = 1.08 ± 0.37; Flat Landing Brook Formation: Zr/TiO2 = 0.107 ± 0.043, Th/Nb = 0.86 ± 0.17. A symmetrical repetition of the footwall-iron formation-hanging wall stratigraphic sequence is observed in DDH-B357, with distinct felsic volcanic rock domains separated by the three iron formations. This is best explained by parasitic F2 folds on the west flank of the south-plunging Brunswick antiform, similar to the fold closures known to host massive sulfide accumulations in the Brunswick No. 6 and No. 12 mines. Iron formation geochemistry and felsic volcanic rock chemostratigraphy from drill core sampling can provide an effective mineral exploration tool for the structurally complex rocks of the Bathurst Mining Camp. Sommaire - Le forage au diamant DDH-B357, situé à 1.5 km au nord du gisement de Sulfures Massifs à Encaissant Volcanique et Sédimentaire (SMEVS) de Zn-Pb-Cu-Ag Brunswick No. 6 recoupe trois horizons exhalatifs au sein des roches volcaniques felsiques diversement altérées des formations de Nepisiguit Falls et de Flat Landing Brook. Ces trois intervalles de formation de fer, impossibles à distinguer pétrographiquement les uns des autres, représentent vraisemblablement des unités sédimentaires hydrothermales cogénétiques sur la base de leur signature géochimique commune: Fe2O3T = 42.9 ± 10.5 % poids, MnO = 5.4 ± 3.1 % poids, des teneurs élevées en métaux usuels (Zn+Pb = 1999 ± 1091 ppm), un fort enrichissement en composantes exhalatives additionnelles (CaO = 5.3 ± 3.9 % poids; P2O5 = 1.43 ± 1.00 % poids), une signature oxydée (Fe/ Mn = 10 ± 6), ainsi qu’une signature d’éléments immobiles communs (Zr/TiO2 = 0.025 ± 0.007) indicative d’une source pélagique. Les roches volcaniques encaissantes calco-alcalines à transitionnelles peuvent êtres reconnues par leur rapport Zr/TiO2, et à un moindre degré par leur rapport Th/Nb: Formation de Nepisiguit Falls: Zr/TiO2 = 0.053 ± 0.004, Th/Nb = 1.08 ± 0.37; Formation de Flat Landing Brook: Zr/TiO2 = 0.107 ± 0.043, Th/Nb = 0.86 ± 0.17. Une répétition symétrique de la séquence stratigraphique Mur-Formation de Fer-Toit a été observée dans le forage DDH-B357, avec des domaines distincts constitués de roches volcaniques felsiques séparés par les trois formations de fer. La meilleure explication est que le flanc ouest de l’anticlinal Brunswick à plongée sud est affecté par des plis parasites F2, similaires aux zones de charnière contenant les sulfures massifs des mines Brunswick No. 6 et No. 12. La géochimie des formations de fer et la chimiostratigraphie des roches volcaniques felsiques en forage peuvent fournir un outil d’exploration minérale efficace dans les roches structuralement complexes du Camp Minier de Bathurst."

Jan 1, 2006

By Z. G. Tao, Y. Y. Peng, W. L. Gong, M. C. He

"This paper presents an overview of the major landslide hazards in open pit mines in China, the currently used landslide control and monitoring techniques, and development of a new slope control technique incorporating the reinforcement, sliding force monitoring, remote sensing and forecasting in one system in order to constrain the displacement of the sliding blocks in the landslide to minimized the influenced area and provide precise warnings timely for the imminent landslides. For implementation of the new technique, a novel rock cable with large deformation and high resistance (also known as HE cable) was developed, which can elongate as long as 2m. At the same time, the necessary and sufficient condition for initiating a landslide and energy balance equations are formulated. Based on the proposed mathematical models and Beidou satellite system, the software and data transmission hardware for remote sensing and forecasting were developed the new landslide control technique has been applied successfully in 245 landslide sites in 12 provinces across China. In this article, two practical application cases in the open pit mines are reported.INTRODUCTIONChina is one of the countries in the world with the most widely distributed landslides and suffering the heaviest damage. According to the incomplete statistics, landslide hazards have caused death of hundreds of people and direct economic losses of several hundred million RMB each year. The landslide hazards have a great impact on the life and property safety of the people, safety of the infrastructure, as well as the social stability. Thus development of new techniques for forecasting and prediction of the landslides is imperative and of great importance. In general, the forecasting and prediction of the landslides consists of three major aspects, i.e. sliding time forecasting, landslide activity intensity forecasting and landslide hazard degree forecasting. Since a considerable part of the landslide-suspected area are adjacent to the residential areas or important infrastructures, development of the advanced landslide control and monitoring techniques to cope with the sliding time forecasting problem is more important.Over the past one hundred years, the most widely used slope monitoring techniques are based on displacement monitoring (Xu, et al. 2007; Toshitaka, 1998). In the early days owing to the limitation of the technology and equipment, the ground surface displacement and underground water level change were inspected mainly by man power for inferring the possibility of a landslide. In recent several decades, more and more ground surface displacement monitoring devices were brought to the market, such as the automatic total station, theodolite, digital level, borehole inclinometer and GPS based instruments, etc. Based on these modern techniques, some advanced instruments have been developed and applied to the landslide monitoring, for example, the “landslides early warning monitoring system” (Leonardo, et al. 2002), the “In-SAR” technique (Reevea, et al. 2000), the GPS and satellite geodetic survey based technique (Reevea, et al. 2000), and real-time telemetry technology (Xu, et al. 2007). These monitoring approaches have made significant contributions to the landslide disaster monitoring and forecasting. The major limitations for the ground surface displacement monitoring techniques are lie in the inconsistence between the displacement in ground surface and that in the sliding surface for the sliding mass, resulting in low degree of forecasting accuracy."

Jan 1, 2015

By K. H. J. Clarke

"ALTHOUGH nickel was not identified as a separate element until a Swedish scientist, Axel Frederick Cronstedt, did so in 17 51, its utilization dates from pre-historic times. From its humble beginnings nickel has grown in importance until, today, in our clocks, television sets, automobiles, and air-planes, in our bridges, tableware, farm implements, and the equipment which processes our food, it is constantly at our service.For convenience in assembly, data and information relative to The Marketing of Nickel will be outlined in five phases: (A) Sources, (B) Distribution, (C) Utilization, (D) Market Development, and (E) Conclusions."

Jan 1, 1960

By J. A. Folinsbee, Andre Robitaille, Tony Y. Chong

"Conventional crushing and grinding is followed by gravity concentration to recover free milling gold. Refractory gold, finely disseminated within the pyrite and arsenopyrite matrix, is recovered by flotation followed by pressure oxidation, cyanidation, and cementation. Non-refractory gold is recovered by cyanidation/CIP processing.A comprehensive test program aimed at improving flotation recovery was initiated in June 1995. Plant testing indicated that flotation tails value could be significantly reduced using mechanical flotation cells. Based on these test results, a flotation circuit that incorporates one of the three existing flotation columns followed by mechanical scavenging and cleaning was developed. Detailed engineering was completed in September 1996. Construction started in February 1997 and was completed in 3 months at a cost of $3.2 million. An on-stream X-ray analyzer was installed to provide real-time arsenic and iron analyses and inferred sulphur value on some of the flotation streams.The new flotation circuit proved to be an instant success. Flotation tails values were reduced by 27%. Final tails solids and solution was reduced from 0.035 to 0 023, and 0.0014 to 0.0006 oz/ton Au, respectively. Based on a mill throughput of 1,620 stpd this decrease in tails value will result in an increased gold production of 7,500 ounces per year. The payback for the project is estimated to be around one year.This paper describes the evolution of the project from bench scale testing to commissioning. Also, the operational and economic impacts on down stream processing are highlighted"

Jan 1, 1998

By Dave Thomas

?Uranium is a common trace metal at the earth?s surface, but these are amazing super-high grade (up to 25%) pods, veins and disseminated uraninite (UO2) near unconformities between Proterozoic siliciclastic red beds and metamorphic basement with graphitic metapelite and radiogenic granite. ?Pitchblende fills extensional features in reactivated fault zones and replaces matrix in sandstone ?One mining district in Canada ?the Athabasca Basin ->30 deposits /prospects -most in eastern ¼of basin -produces 1/3 of world?s U -employs northerners -VERY high tech -VERY high safety standards Unconformity-associated uranium depositsUnconformity-deposits

May 1, 2006

By S. Bergquist

In this paper, it is investigated how different types of automation would affect the safety for workers in asphalt paving. The risk for the workers on road construction sites is consistently high in comparison to the average risk of the working population. Automation has been suggested as an alternative for improving the safety in roadside construction assuming that removing workers will inherently eliminate the risk of them being injured. In this paper, the potential for improving the safety using automation is analyzed in detail. By investigating accident statistics and understanding the type of accidents that appear, several different automated functions for increased safety are proposed and described. Based on available statistics, it is possible to estimate the safety benefit, as the reduction in fatalities, for several of the proposed functions. The highest safety benefit would be achieved by automating the road traffic driving through the work zones. This has the potential of reducing the total number of road worker fatalities with over 30 %. In addition, it would decrease the number of road traffic accidents in work zones. Automation of construction machinery and dump-trucks also has the potential to increase the safety.

Aug 1, 2013

By M. R. Khalesi, S. Bellec, C. Bazin, D. Hodouin

Batch grinding tests conducted on a gold ore indicated that gold is not randomly distributed within the size fractions of the ground ore. Since gold leaching performances were found to be dependent of the size of the gold carrying particles an integrated gold ore grinding-leaching simulator should incorporate a method to predict the gold size distribution of a ground ore. The paper describes the results obtained from batch grinding tests showing the non random distribution of gold within the size intervals of a ground ore and the initial developments of a grinding model to predict the gold size distribution in a batch grinding product.

Jan 1, 2011