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By Martin Bergeron

Producteur d?or de taille intermédiaire Mines Aurizon Ltée Bureau-chef àVancouverMine et projets localisés au Québec2

May 1, 2011

By B. W. Cavender

Innovative mining and metallurgical operating techniques and processes can be identified and developed by analyzing changes as they occurs within the mine, plant, technology or industry. Sources of change to be monitored for innovative opportunities include unexpected successes or failures, incongruities between perceived and actual events, process needs, changes in perceptions and the development of new knowledge. Innovation can be organized, practiced and managed. The perception of change as an opportunity rather than a threat is mandatory, as is the systematic measurement of innovative performance. Innovation is enhanced by specifically designed policies regarding organizational structure and staffing, daily management practices and compensation and incentives.

Jan 1, 1996

By Jacek Paraszczak

Possibility to move human workers away from dangerous places ?enhanced safety and improved working environment; ? Increase of actual operational time: ? Less losses due to shift changes, regulatory breaks, blasting periods, ventilation after blasting, etc.; ? Possibility to work in extremely dangerous conditions where man-operated machine could not be used (for example: ST-14 loader in backfilling operations in the Kemimine, following roof collapse). Reduction of the production cost through: ? Lower maintenance cost (less damage due to operator?s mistakes and no machine abuse); ? Higher productivity and effectiveness of the equipment (less machines to meet production targets, less operators required, lesser maintenance cost...). ? Although personnel health and safety are key drivers behind autonomous operation of mobile equipment in U/G mines, with significant capital and operation costs one expects to achieve: ? Productivity higher, or at least equal to that offered by man-operated equipment and systems; ? Lower production cost. Therefore, high effectiveness of the autonomous equipment is crucial to succeed.

May 1, 2010

Whereas traditionally, stable isotope research has been directed towards resource exploration and development, it is finding more frequentapplications in helping to assess the impacts of resource utilization upon ecosystems. Among the many pursuits, two themes are evident:(1) tracing the transport and conversions of pollutants in the environment and(2) better understanding of the interplay among environmental receptors, e.g. food web studies. Stable isotope data are used primarily to identify the presence of pollutants in the environment and with a few exceptions, the consequence of their presence must be assessed by other techniques. Increasing attention has been given to the isotopic composition of humans with many potential applications in areas such as paleodiets, medicine, and criminology. In this brief overview examples are used from the Pacific Rim to illustrate the above concepts. Stable isotope data will undoubtedly play an increasing role in multi-disciplinary research in the Pacific Rim. However, consideration should be given to more effective strategies, e.g. networking, for pursuing large scale problems such as long range circulation of pollutants.

Jan 1, 1990

By William Petrul

Image analysis studies were performed on mill products from laboratory flotation tests of the Zn-Pb ore from the Faro deposit in Yukon, Canada, to determine mineral liberations at specific grinds and to predict recoveries at optimum flotation conditions. The minimum and optimum grinds for liberating sphalerite and galena were predicted from size analysis data for the minerals in large ore pieces, and determined by image analysis studies of the mill products. The determined optimum grinds are about 2 Tyler mesh sizes larger than predicted because sane of the fine grained sphalerite and galena occurs in interstices between coarser grained pyrite and is liberated when the pyrite grains are broken apart. Materials balance calculations were performed on the analyzed values for the liberated and unliberated sphalerite and galenaa to determine their distributions in the mill products. The laboratory flotation tests recovered 74% of the sphalerite and 83% of the galena in Zn and Pb concentrates respectively. The mineral evaluation study indicates that the optimum recovery for sphalerite and galena are 85 and 83% respectively. The company is currently recovering 80% 'of the sphalerite and 82% of the galena.

Jan 1, 1989

By Weimin F

In the last decade, great strides have been made in the raise boring technique in China. Extensively, the drilling and blasting method has been replaced by the mechanized raising method since 1980. There are now over 3C raise drills operating in more than 20 mines. The diameters for shaft boring varies from 500mm to 2000mm, and to depths up to 90m. Tlis paper mainly describes the performance, mtLin technical achievments and applications of all four kinds of raise drills, and auxiliary equipment. Finally, some recommend- ations for future improvement in the raise boring technique are presented also.

Jan 1, 1987

By C-D. Johansson, B. Ögren, B. M. Ludvigsson, K-Å. Johansson, R. Lindh, G. Berg, M. Maliarik

This paper presents the High Current Density (HCD) Silver Electrorefining Process. A 25-year history of development of the silver electrorefining process as well as associated equipment is given. The process is simple and robust, but at the same time highly automated. With low operating costs and man power requirement it allows consistent production of 99.99 % quality cathode silver. The process ensures that no toxic gases are formed in the working environment. Silver Electrorefining is a heart of a Silver Refinery plant covering the complete range of processes from casting of silver Doré anodes to casting of the bars of refined silver or/and silver granulation. The process has been successfully applied at 11 installations world-wide with plant capacities ranging from 30 to 1500 tpa.

Jan 1, 2014

By Daniel Adolfsson, Ryan Robinson, Fenwei Su, Jelena Blagojevic

"Cold bonded briquetting of steel plant by-products has proven to be a viable recycling alternative concerning technology, economy and environment in both the traditional blast furnace route and the direct reduction process. A critical parameter in cold bonded briquettes is the type and amount of binder used during production. The binder material must meet certain quality requirements concerning low and high temperature strength, chemistry and economy. Currently, SSAB Tunnplåt uses ordinary Portland cement (OPC) as binder in their cold bonded briquettes. In order to improve binder quality and possibly decrease OPC dependency, a binder feasibility study has been conducted concerning an internal by-product, ladle slag, as a supplement and/or partial substitute for OPC. Several characterization techniques have been used to study the behaviour of ladle slag, these include: XRD, XRF, SEM, glass content analysis, calorimetric analysis, particle size distribution and thermochemical stability considerations concerning the CaO-Al2O3-SiO2 system.IntroductionRecently, a project was initiated at SSAB Tunnplåt AB, in Sweden, which aimed at reducing the amount of ordinary Portland cement (OPC) as hydraulic binder in cold bonded briquettes by partly replacing it with ladle slag. OPC is traditionally used within civil engineering, and widely accepted as a hydraulic binder in a number of different applications. OPC consists of four major crystalline phases, i.e. C3S, C2S, C3A and C4AF. Tricalcium aluminate as well as the ferrite phase in OPC reacts very quickly with water, for this reason gypsum is added to the clinker in order to retard these reactions. The fact that gypsum is present in the system limits the recycling of briquettes to the BOF, since the presence of gypsum during steelmaking results in a significant amount of sulphur emissions. The latter along with the expense that follows, makes it worthwhile to consider alternatives for OPC as binder in cold bonded briquettes."

Jan 1, 2008

By Raymond D. Sloan

Development and exploration in Oklahoma showed a definite increase in 1941 over 1940 in production, wildcat activity and total well completions. Geological and geophysical work continued and possibly increased slightly in amount. Oklahoma retained third place in the ranking of oil-producing states of the nation, topped only by Texas and California, and followed by Illinois in fourth position. Production averaged 416,800 bbl. daily, a 1.7 per cent increase, as compared with 409,900 bbl. daily for the year 1940. Maintenance of the state's relatively stable producing rate resulted from the discovery of numerous small pools, the recombing of old areas, the establishment of new producing horizons, and the drilling of an increased number of marginal wells. The market for the Mid-Continent crude was strengthened materially to meet the increased demand. Coincident with a deeline in production in Illinois, shipment of Oklahoma-Kansas crude to the eastern points averaged 453,000 bbl. per day, an increase of 49.4 per cent as compared with 1940. The movement south amounted to an average of 42,000 bbl. per day, a loss of 41.7 per cent. Secondary-recovery programs in Oklahoma were given more consideration, operators realizing that in the future many pools would necessarily have to resort to this type of operation. Five permits for water-flooding were issued by the Corporation Commission during the year. These projects were in Rogers, Wagoner and Nowata Counties, in the shallow northeastern area, which has relatively extensive development of this type in the Bartles-ville sand at from 600 to 1000 ft. in depth. Gas repressuring of an individual lease in the 35-year old Glenn pool, Creek County, proved relatively successful, and after a year's operation was extended to cover a much larger area, with several operators participating. More of this type of work is expected in the future; however, it was given an initial setback when the legislative proposal authorizing secondary recovery in the Wilcox zone of Oklahoma's largest pool, the Oklahoma City pool, was pigeonholed by the committee. A continuation of the low discovery rates within the state would possibly lead to a revival of interest in the project. Many pools formerly classified as prorated areas were removed from this classification and transferred into the group of settled production. At the close of the year the issuance of the Federal Conservation Order M-68 and the interrelated Preference Rating Order P-98 caused a sharp decline in drilling operations, which is expected to continue until such operations are stabilized at a lower rate. The ultimate effect of these two orders on discoveries, production and reserves is a matter of speculation and conjecture. During the year, 2110 new wells were drilled, an increase of approximately 18 per cent as compared with the previous year. Of the total, 1235 were oil wells with a combined initial potential of 342,754 bbl. daily, 178 were gas wells with a total

Jan 1, 1942

By Raymond D. Sloan

Development and exploration in Oklahoma showed a definite increase in 1941 over 1940 in production, wildcat activity and total well completions. Geological and geophysical work continued and possibly increased slightly in amount. Oklahoma retained third place in the ranking of oil-producing states of the nation, topped only by Texas and California, and followed by Illinois in fourth position. Production averaged 416,800 bbl. daily, a 1.7 per cent increase, as compared with 409,900 bbl. daily for the year 1940. Maintenance of the state's relatively stable producing rate resulted from the discovery of numerous small pools, the recombing of old areas, the establishment of new producing horizons, and the drilling of an increased number of marginal wells. The market for the Mid-Continent crude was strengthened materially to meet the increased demand. Coincident with a deeline in production in Illinois, shipment of Oklahoma-Kansas crude to the eastern points averaged 453,000 bbl. per day, an increase of 49.4 per cent as compared with 1940. The movement south amounted to an average of 42,000 bbl. per day, a loss of 41.7 per cent. Secondary-recovery programs in Oklahoma were given more consideration, operators realizing that in the future many pools would necessarily have to resort to this type of operation. Five permits for water-flooding were issued by the Corporation Commission during the year. These projects were in Rogers, Wagoner and Nowata Counties, in the shallow northeastern area, which has relatively extensive development of this type in the Bartles-ville sand at from 600 to 1000 ft. in depth. Gas repressuring of an individual lease in the 35-year old Glenn pool, Creek County, proved relatively successful, and after a year's operation was extended to cover a much larger area, with several operators participating. More of this type of work is expected in the future; however, it was given an initial setback when the legislative proposal authorizing secondary recovery in the Wilcox zone of Oklahoma's largest pool, the Oklahoma City pool, was pigeonholed by the committee. A continuation of the low discovery rates within the state would possibly lead to a revival of interest in the project. Many pools formerly classified as prorated areas were removed from this classification and transferred into the group of settled production. At the close of the year the issuance of the Federal Conservation Order M-68 and the interrelated Preference Rating Order P-98 caused a sharp decline in drilling operations, which is expected to continue until such operations are stabilized at a lower rate. The ultimate effect of these two orders on discoveries, production and reserves is a matter of speculation and conjecture. During the year, 2110 new wells were drilled, an increase of approximately 18 per cent as compared with the previous year. Of the total, 1235 were oil wells with a combined initial potential of 342,754 bbl. daily, 178 were gas wells with a total

Jan 1, 1942

By W. R. Crane

THE support of roof in mines is dependent largely on the character of the top rock and its occurrence. The formations overlying the orebed in the Birmingham district are sandstone and slate. The sandstone occurs in beds of sufficient thickness to constitute important elements in the system of support; the slate is relatively strong but is thinly stratified. The alternating beds of sandstone and slate furnish an excellent combination in that the former are strong and the latter are impervious; however, their continuity is broken by jointing or slip planes. The thickness, and consequent weight of the overlying formations, is important in so far as the size and arrangement of pillars are concerned but may be relatively unimportant, temporarily at least, as a factor in the support of the roof. The position of the respective beds of sandstone and slate, their relative thickness, and their inherent weakness because of the occurrence of faults and folds, may exert a predominating influence on their support in place, which is affected only in part by the weight of the cover. The only mine in this district that operates under a cover of approximately 2000 ft. (1900 ft.) is the Shannon so-called "twin slope," situated 14,000 ft. southeast of the portal of the No. 7 mine of the Tennessee Coal, Iron, & Railroad Co. The conditions in this mine indicate what may be expected in other mines when the same depth is attained; in fact the effect of pressure is shown in several mines that have not reached two-thirds of that depth. It is evident then that conditions affecting the support of roof will not improve but rather will become more difficult with the extension of the mines into the valley under a constantly increasing weight of cover. Further, the difficulties will probably be augmented by the occurrence of faults and other disturbed ground, the presence and position of which at present are largely unknown.

Jan 9, 1924

President Robert E. Murray opened the meeting at 9:30 a.m. He called on the Auditing Committee to give its report. Jack Leech read the report and asked that it be approved. A motion was made, seconded and carried. The Resolutions Committee was asked to present its report. Mr. J. F. Ratchye submitted the following: (1) RESOLVED. Whereas, in the year since the last convention of The Rocky Mountain Coal Mining Institute, the Institute and the Coal Mining industry have suffered the loss through death of the services of: James L. Elder William T. Gibbs Julian E. Tobey John H. Plehn NOW, THEREFORE, BE IT RESOLVED, that there be spread upon the minutes of The Rocky Mountain Coal Mining Institute recognition of the passing of these members, who have so greatly contributed to the advancement of the industry, both nationally and in the Rocky Mountain area, and that a copy of this resolution be sent to the next of kin as evidence of the sincere regard and sympathy of the members of the Institute. (2) RESOLVED: that in recognition of faithful service to the coal industry generally, and to this Institute, Life Membership in The Rocky Mountain Coal Mining Institute be hereby con¬ferred upon the following members:

Jan 1, 1979

By Carmina Quintanar, Mario Palominos

"The mining industry is currently facing significant challenges to identify and adopt sustainable collector chemistry that effectively recover value minerals in difficult-to-process low-grade resources. These are typically characterized by complex mineralogy and the presence of significant amounts of penalty gangue sulfide minerals, especially pyrit which is a challenge to separate from value minerals at many major mine operations. Three chemical strategies for dealing with gangue sulfides and penalty elements are: a) selective flotation of value minerals while rejecting penalty minerals in the whole circuit, b) rejecting penalty minerals in an appropriate part of the circuit using selective depressants, c) using a combination of selective collectors and depressants in appropriate parts of the circuit. This paper will evaluate different strategies for dealing with those penalty elements and propose the most efficient alternative. New products and application technologies have been developed in the past 25 years by Cytec for implementing these strategies as dictated by the particular needs of a given plant. However, in recognition of the growing interest in meeting the sustainability challenges, Cytec Research and Development have been focused in the development of greener products (collectors, modifiers and frothers) and processes using FLOTATION MATRIX 100TM approach used to develop the optimal collector system for each specific ore. An overview of these new developments is given in this paper using case studies of application of selective collectors and polymeric modifiers including the newer, greener chemistries."

Jan 1, 2014

By Royle A. G

The paper describes a geostatistical structural analysis of an 80 square mile lease of the Athabasca tar sands. Each step of the analysis is presented with the ultimate objective of condensing the principal structural characteristics of the chosen regionalised variables into the opera- tional form of the variogram model. The variogram model is then used to form kriged local and global estimates, with the corresponding estimation errors.

Jan 1, 1977

By Manuel Ruiz, Esteban Chumpitaz, Ricardo Huancaya

"En Cía. Minera Coimolache estamos comprometidos con el cuidado del medio ambiente y la generación de energía limpia que nos permite optimizar los costos de operación, motivo de ello estamos apostando por el uso de energías renovables para las facilidades de nuestras operaciones mineras. Se conoce como energía renovable aquella cuya fuente es inagotable, llega a nuestro planeta o existe en él. Ejemplo de esta energía tenemos la energía solar, eólica, geotérmica, biomasa y las marinas. Este tipo de energía también se considera como limpias, ya que no genera impacto negativo al medio ambiente por el contrario es energía que minimiza los efectos del calentamiento global."

Sep 1, 2017

By Cesimiro Fabian

The crystallite size of copper electrodeposits was determined by X-Ray powder diffraction analysis using a General Area Detector Diffraction Solution (GADDS) diffractometer. Crystallite size was calculated for copper thin films which were deposited on a 316 stainless steel rotating cylinder electrode (RCE) in the presence and absence of additive ?A?. The crystallite size was calculated from a corrected full width at half maximum (FWHM) of the [110] peak profile using the Scherrer equation. The test of significant difference on crystallite size was derived using Kruskal-Wallis method. It was found that in the absence of the additive the median crystallite size was 426, which decreased to 364 in the presence of the additive. As the additive degraded, the crystallite size increased to a size similar to that observed in the absence of additive.

Jan 1, 2003

By R. J. Cowan

In the art of cementation a controversy has been going on for years as to whether solid or gaseous carbon is the active agent in carburizing steel. More recently opinion has crystallized into a compromise to the effect that carburizing is a gaseous cementation of steel in the presence of solid carbon. The importance of this theory has a particular bearing upon the work to be described. In the art of carburizing, use is commonly made of such words as '' Catalytic" "atomic," "nascent" and "activated," in an attempt to describe the process. These words are used indiscriminately. For instance, the gas is said to be "catalytic" and carbon to be "nascent," or vice versa. In using these expressions, investigators are confirming the acceptance in their minds of the active conditions of both gas and carbon in the cementation process. Reactions at Metal Surfaces For many years attention has been directed to the consideration of reactions that occur on metal surfaces. When heated under the influence of certain metals a complex gas will be broken down and one of the constituents thereof usually found to be very active chemically in combining with the metal. The process of nitriding is an example of this type of reaction. In this case ammonia (NH3) breaks down at the metal surface and the nitrogen which is thus liberated reacts with the surface to form a nitride whereas molecular nitrogen not so liberated is inert and will not react chemically with the metal. Whatever term or terms may be used to describe such reactions, the fact remains that they are highly important and valuable in their commercial applications. Since the metal surface plays so important a part in these reactions, it is evident that any accumulation of reaction products thereon interferes seriously with the progress of the reactions. For this reason it is desirable to remove all such products as rapidly as they are formed in order to bring active gas into contact with the surface and thus facilitate the desired reactions. This is accomplished best by conducting the operation in a continuous manner, thereby causing the reacting gases to pass over the

Jan 1, 1931

By Stuart M. S, Allen P. B

The Childe Harold deposit was mined by the Granny Smith Joint Venture (GSJV) from late-March through to early-December 1993. This was a fast-tracked mining project whose history began with an offer to purchase agreement being signed at the end of October 1992. A feasibility study was completed by the end of December 1992 after completion of a reverse circulation (RC) and diamond drilling program. Subsequent additional definition drilling culminated in a remodelling of the reserve by March 1993, by which time all necessary governmental and company approvals had been granted. The crucial aspect of mining Childe Harold quickly was to maintain oxide ore supply to the Granny Smith mill at the maximum possible rate for blending with existing fresh ore stocks. As a result, high production rates had to be balanced with

Jan 1, 1994

By James R. Hein, Jane Reid, Robert W. Embley, Se-Won Chang, Randolph A. Koski

"Abstract - This is the first reported occurrence of an active hydrothermal field in an oceanic fracture zone setting. The hydrothermal field occurs in a pull-apart basin within the Blanco Fracture Zone (BFZ), which has four distinct mineral deposit types: (1) barite mounds and chimneys, (2) barite stockwork breccia, (3) silica-barite beds, and (4) silica, barite, and Fe-Mn oxyhydroxide in sediments. All deposit types contain minor amounts of sulfides. In barite stockwork, silica-barite beds, and mineralized sediment, Ba, Pb, Ag, S, Au, Zn, Cu, Hg, Tl, As, Mo, Sb, U, Cd, and Cu are enriched relative to unmineralized rocks and sediments of the BFZ. Fe and Mn are not enriched in the barite stockwork or silica-barite beds, but along with P, Co, and Mg are enriched in the mineralized sediments. Silver contents in deposits of the hydrothermal field range up to 86 ppm, gold to 0.7 ppm, zinc to 3.2%, copper to 0.8%, and barium to 22%.Mineralization occurred by diffuse, low to intermediate temperature (mostly <250°C) discharge of hydrothermal fluids through pillow lavas and ponds of mixed volcaniclastic and biosiliceous sediments. Bacterial mats were mineralized by silica, barite, and minor Fe hydroxides, or less commonly, by Mn oxyhydroxides. Pervasive mineralization of bacterial mats resulted in formation of silica- barite beds. Silica precipitated from hydrothermal fluids by conductive cooling and mixing with seawater. Sulfate, U, and rare earth elements (REEs) in barite were derived from seawater, whereas the REE content of hydrothermal silica deposits and mineralized sediments is associated with the aluminosilicate detrital fraction. Fe-, Zn-, Cu-, Pb-, and Hg-sulfide minerals, Ba in barite, and Eu in all mineralized deposits were derived from hydrothermal fluids. Manganese oxides and associated elements (Co, Sb, Mo, W, Cl, and Cu) and Fe oxides and associated elements (Be, B, P, and Mo) precipitated as the result of mixing of hydrothermal fluids with seawater."

Jan 1, 1999

By J. L. Huiatt, D. G. Foot

The Bureau of Mines, U.S. Department of the Interior, investigated methods of recovering potash values from process and waste brines. Laboratory pan evaporation of four chloride brines produced crude salts containing predominantly sylvite, halite and carnallite. Six sulfate- chloride brines produced crude salts containing primarily schoenite, kainite, leonite, sylvite, carnallite, and halite. Potash grades ranged from 7.2% to 22.2% K20, and recoveries by crystallization ranged from 85% to 99%. Sylvite flotation from chloride evaporites with amine collector, recovered 90% to 97% of the potash in a concentrate containing 54.3% to 60.3% K20. Fatty acid flotation of the high sulfate evaporite recovered 78% of the sulfate minerals in a 28%-K20 concentrate. Flotation of the remaining chloride minerals with amine collector recovered 80% of the potash in a 59.7%-K20 concentrate. Solar evaporation of 37 854 L (10,000 gal.) of brine recovered 99% of the potash in a crude evaporite containing 24.5% schoenite and 20% sylvite. Flotation in a 45-kglh (100-lblh) continuous flotation unit recovered over 95% of the potash in schoenite and sylvite concentrates, containing 28% and 62.3% K20, respectively. An economic evaluation is included.

Jan 1, 1985