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At 14%, the representation of women working in the mining industry is the lowest among primary industry categories in Canada1. With reference to mining operations and senior leadership, the gap in the industry is even more pronounced. In an effort to narrow the gender gap, recent industry, education, and policy efforts have been made to increase the number of women entering the industry through career awareness and early career recruitment strategies. These strategies implied that by increasing the numbers of women entering the industry there would be a natural progression of women into the hierarchies of organizations. Efforts to retain women in the industry have focused around removing career barriers such as reviewing flexible work practices and programs directed at work life balance. At this time, these efforts have resulted in negligible fluctuations to the gender gap within the industry. This research investigates the under-representation of Highly Qualified Women (HQW), and the interaction of workplace culture on their career advancement and retention within the industry. HQW (women with a bachelor?s degree or higher) are the focus of the work as they represent an essential source of leadership and technical capacity for mining organizations. This paper is based on the results of a survey of 170 HQW working in the Canadian mining sector. The findings from this research suggest that HQWs careers in mining are stalled, despite a strong indication by respondents of interest in their professional career advancement. With regards to workplace culture, respondents indicated that blatant forms of gender discrimination have been reduced in mining workplaces; however, exclusion from informal networks, implicit bias and subtler forms of workplace discrimination persist. Utilizing a framework to assess the workplace culture for women in attracting and retaining their employment, respondents provided detailed information on the aspects of workplace culture that are most problematic in relation to women?s career development in mining. Women consistently identified problematic workplace culture as a significant barrier to the career advancement and retention of women within the industry. The representation of women within the labour force will likely remain stagnant until the industry addresses workplace culture within the industry, and makes strategic efforts to develop inclusive cultures throughout mining and supportive organizations.

Aug 1, 2013

By R. D. Vaughn

The analysis of laminar flow of power-law non-Newtonian fluids in narrow, eccentric annuli is employed in this paper to discuss the problems of lubricant flow in journa! bearings and of errors introduced by eccentricity in experimental studies with concentric annuli on extruders and wellbore annuli. The velocity profile and pressure loss-flow rate equations are developed for the laminar flow region. In addition, the expected error in flow rate and pressure-loss measurements for concentric annuli as a result of eccentricity is determined. For example, a 10 per cent displacement of the core of an almost concentric annul us would cause a 1.8 per cent decrease in the observed pressure loss for a fluid with a power-law exponent n of 0.25. The corresponding increase in the observed volumetric flow rate would be 7. 5 per cent. INTRODUCTION Non-Newtonianism and eccentricity occur simultaneously in two engineering problems: (1) flow of lubricants in journal-bearings and pressure-reducing bushings, and (2) flow of non-Newtonian fluids in plastic extruders and wellbore annuli. The lubricants used for moving parts are often non-Newtonian in character — often they are plastic in behavior. A solution to the problem of flow of non-Newtonian fluids in narrow eccentric annuli is particularly pertinent to this problem. In all experimental studies of laminar flow of fluids in concentric annuli, such as in extruders and well casings, the error due to eccentricity must be estimated or studied. A number of publicationsl-4,6,7 have dealt with this problem for Newtonian fluids; however, I am not aware of work for non-Newtonian fluids. This work is directed to the non-Newtonian problem. Before the solution to the problem is given, the pertinent conclusions from the work on Newtonian fluids will be reviewed. Heyda 1 and Redberger and Charles 2 have published general solutions to the problem of the laminar flow of Newtonian fluids in eccentric annuli, apparently without knowing of the earlier work of Ca ld well 3 and Bairstow and Berry,4 which is reported by Dryden, et al. 5 Although several mathematical routes are encompassed by the work of these authors, the results appear to be equivalent. Redberger and Charles2 show that the error caused by eccentricity in concentric annuli is negligible for small diameter ratios (k < 0.5); however, for large diameter ratios (k + l), the error in the predicted flow rate can be as great as 100 per cent or more. Partial solutions to the problem are available from the work of Dryden,5 Tao and Donovan6 and Piercy, et a1.7 Tao and Donovan examined the case of flow in narrow, eccentric annuli (k + 1) with and without rotation of the annular core. These authors also reviewed previous work on this subject and verified their approach with experimental data. Dryden gives the solution for the limiting case of complete eccentricity or tangency. Piercy, et a l. published an early solution to the problem of narrow eccentric annular flow. The conclusions of Redberger and Charles2 and the experimental proof of Tao and Donovan6 both suggest that the region of large diameter ratios (k + 1) is of main interest and that the parallel planes approximation to the solution in this region is satisfactory. This method will now be extended to the laminar flow of non-Newtonian fluids in narrow eccentric annuli. THEORETICAL SOLUTION The geometrical aspects of the problem are illustrated in Fig. 1. To represent the non-Newtonian fluid the power-law model was selected. This model has many disadvantages which have been pointed out; nevertheless, its simplicity, its frequent and wide applicability justify its use in this work. Fredrickson and Bird8 and Savins9 have used it as a basis for a theoretical study of laminar flow of non-Newtonian fluids in concentric annuli.

Jan 1, 1966

By A. V. Tarasov

The insufficient scientific and technical level of a number of operations in the nonferrous metals industry encourages development of new processes and equipment, including smelting in liquid bath, flame-type sparged smelting unit for combined processes, electrothermal process with the use of alternating current (PDF furnace), electrothermal processing of complex raw materials and intermediate products at nonferrous metallurgical plants, etc. One of the most important aspects for development of new processes and equipment in the Gintsvetmet Institute is their environmental safety. Special attention is paid to environmental protection measures, which is also of important economic and social significance. This refers also to a complete extent to processing of reserves of man-made raw materials and wastes available at the existing operations with the use of innovative techniques ensuring not only resource conservation and environmental protection, but also abatement of negative impact on the nature due to accumulated industrial and domestic waste, reclamation of the land used for waste disposal and recycling of nonferrous metals. Technologies and equipment developed in the Gintsvetmet Institute and based on electrothermal processes determine the prospects for ensuring more integrated usage of ores and man-made raw materials.

Jan 1, 2006

ZAY JEFFRIES (author&apos;s reply to discussion *).-Messrs. Merica&apos;s and Humfrey&apos;s criticisms of some of my conclusions are rendered in the true scientific spirit by means of which differences of opinion are gradually smoothed out and all participants are benefited. It is true that the statement of generalizations on such a complex subject is hazardous, but I shall endeavor to point out the explanations for the discrepancies noted. Owing to the fact that I am now submitting a long paper on the same general subject to the Institute, my present remarks will be brief. Dr. Meric&s Assumptions&apos; I agree with No. 1 and No. 2, with the modification that the A (amorphous) metal between grains of annealed metal has substantially the same properties as that at slip planes in deformed metal, but the two have different arrangements with reference to C (crystalline) metal and they may be in different conditions as regards internal stress, thickness, and nature of contact with C metal. Assumption 3.-I believe Fig. 1 is wrong. I know of no evidence to substantiate the curves. I believe cc (elongation of C phase) = 0 (approximately) at all temperatures and ?A (elongation of A phase) has finite values at elevated temperatures only; but these play no important direct role in the ordinary deformation of metals at low temperatures. I believe Ec (elastic limit of C phase) = Tc (tensile strength of C phase) because as soon as C metal begins to deform permanently it would rupture were it not for the A metal generated by its breakdown. We know that Ec = Tc in brittle crystals and a crystal cannot be permanently deformed without generation of A metal. Therefore Dr. Merica&apos;s

Jan 12, 1918

By Colin C. Harris, Jie Zheng, P. Sornasundaran

Powder surface and polymer structural changes during stirred milling have been studied as a function of grinding time, solid concentration and polymer molecular weight. It was found that specific surface area of limestone particles can be increased over 100% by using polymer additives. Particle surface and polymer structure were also found to change during grinding. Powder surface and polymer properties have been determined using Surface Tension, Fluorescence, TOC and HPLC/GPC analysis, and surface and polymer properties are correlated with operating variables and the mechanisms involved are explored. Particularly, the fragmentation of the polymer molecules was found to occur during long term grinding and this was beneficial for ultrafine grinding.

Jan 1, 1998

By Leigh Freeman

This article provides an overview for a series of leadership development workshops offered through the SME Young Leaders Program. The first of these workshops, “Accelerated Development Plan,” will be held at the upcoming SME Annual Meeting in St. Louis, MO on Sunday, March 26. How does a foundation of technical competencies relate to the development of social competencies necessary for management and leadership roles in the resource sectors? Technical competencies provide the foundation for a successful career. Social competencies provide the framework on that foundation. Successful leaders will be those who develop competencies in all areas.

Jan 1, 2006

By J. G. Thompson

OXYGEN, nitrogen and hydrogen are present in practically all metals in one or more of the following forms: (1) molecular gas in blowholes or blisters, (2) combined in nonmetallic inclusions such as nitrides, oxides or silicates, and (3) in solid solution in the metal. Gaseous elements, in some of these forms, are encountered in practically all metals and alloys but possibly have received most publicity in connection with iron and steel. In fact, the entire steel industry depends upon the control of the oxygen content during the refining process, as well as in the finished material, and it was only after the adoption of the use of efficient deoxidizers such as manganese that the production of good steel with a low carbon content became possible. In normally clean, sound steel the amount of hydrogen is negligible and the amounts of oxygen and nitrogen vary from a few thousandths to a few hundredths per cent. However, many of the effects attributed(27,31,40.41,53,54,55,56,62) ? to the presence of these elements are important and at first glance appear to be out of proportion to the amounts of impurities involved. The presence of oxygen is believed to affect the solubility of carbon in austenite and ferrite and thereby to affect the structure of the iron or steel. Such properties as strength, hardness, ductility, elastic limit, impact resistance, magnetic permeability, tendency toward caustic embrittlement, irregularity in carburization, the cutting life of tools, certain corrosion phenomena, the presence of flakes, seams, bands, ghost lines and hair cracks, and the tendency to age-harden, all have been attributed to the presence of oxygen.

Jan 1, 1932

By D. Boufounos

The large open pit areas of surface mining as well as the huge quantities of residues generated during the digestion of bauxite with sodium hydroxide solution to produce alumina are considered as the most important environmental problems associated with the exploitation of bauxites. Aluminum of Greece, which is the only aluminum refinery in the country, located in Agios Nicolaos, Paralia Distomou, Viotia, produces almost 680.000 tones of bauxite residue annually which is pumped through pipes from the refinery to the sea bed of Antikira gulf. In order to avoid any kind of environmental problems related to this disposal method and to reduce the total volume of bauxite residue disposed of in the environment, Aluminium of Greece investigates several alternatives for bauxite residue utilization. In this framework, it also examines the potential use of bauxite residues as a filler in abandoned mining open pits. Bauxite residues are mainly composed of fine particles of silica, aluminum, iron, calcium and titanium oxides and hydroxides. Furthermore, the material presents low hydraulic conductivity, slightly higher than the limit posed for low permeability layers by the EC landfill directive. Based on these properties the dry disposal method was selected for disposing bauxite residues in mining open pits since it has many advantages such as reduced overall disposal cost, effective use of land and minimum environmental impacts. The results obtained for this method, which is investigated at demonstration scale, are presented in this paper.

Jan 1, 2005

By Thomas M. Barczak

Wood cribs have been the dominant form of supplemental support in coal mining for many years. Recently, there has been a renewed interest in prop supports as a replacement for wood cribbing due to the increasing cost of mine timber and engineering advancements in prop design to improve their stability and yield capability. Prop supports generally consume less material, can be installed in less time with less labor, and provide less restriction to mine ventilation than wood crib supports. Several prop supports are now available or under development&apos;. These include: (1) Strata Products Propsetter? Support System; (2) Heintzmann ACS and Super Prop; (3) MBK-Hydraulik MEGA prop; (4) Advanced Mining Technology Inc. (AMTI) BTS Mortar prop; (5) Dywidag Coal Post; (6) Western Support Systems YIPPI support; and (7) "The Can" support by Burrell Mining Products. A comparison of the performance and cost of these support systems to wood cribs is made to provide mine operators with information needed to assess their application potential. Examples of current underground installations are discussed. Included in this assessment are full scale tests of these supports conducted in the U.S. Bureau of Mines&apos; Mine Roof Simulator.

Jan 1, 1995

By D. Bessinger

The present paper provides a brief overview of the thermodynamics of titania rich slags, an outline of the Multi-Phase Equilibrium (MPE) package and its application to ilmenite smelting. Through assessment of published experimental data on various systems containing TiOx, it was found that despite considerable scatter in measured phase equilibria data for the binary Ti2O3-TiO2system,the behaviour of binary and higher order titania rich slags and oxide solid solutions phases could be represented by solution models in the MPE package. Results from the applications of the MPE model on the stability of solid phases and slag-refractory interactions will be presented and discussed. Parallels will be drawn between the predictions by the model and observations made during pilot plant tests. Key words: Thermodynamics, titania slags, ilmenite smelting, phase equilibria, refractory.

Jan 1, 2003

By Alden B. Greninger

The study of mosaic structure of crystals1 has been confined until recently to the field of theoretical physics. Crystallographers, in general, have neglected the subject, although X-ray crystallographers constantly make use of formulas for intensities of X-ray reflection as modified by mosaic structure. Work on mosaic structure has centered chiefly on the task of proving or disproving the secondary-structure theory of Zwicky,² and very little attention has been paid to the visible imperfections of crystals. A. Goetz has been responsible for most of the supposed experimental confirmations of Zwicky&apos;s theory.3 On the other hand, Smckal,4 and Orowan,5 among others, maintain that there is neither theoretical nor experimental evidence to substantiate Zwicky&apos;s secondary structure. Lately the subject has been intensively investigated by Buerger,6 one of whose recent papers led to a symposium on mosaic structures.&apos;

Jan 1, 1935

By Alden B. Greninger

The study of mosaic structure of crystals1 has been confined until recently to the field of theoretical physics. Crystallographers, in general, have neglected the subject, although X-ray crystallographers constantly make use of formulas for intensities of X-ray reflection as modified by mosaic structure. Work on mosaic structure has centered chiefly on the task of proving or disproving the secondary-structure theory of Zwicky,² and very little attention has been paid to the visible imperfections of crystals. A. Goetz has been responsible for most of the supposed experimental confirmations of Zwicky&apos;s theory.3 On the other hand, Smckal,4 and Orowan,5 among others, maintain that there is neither theoretical nor experimental evidence to substantiate Zwicky&apos;s secondary structure. Lately the subject has been intensively investigated by Buerger,6 one of whose recent papers led to a symposium on mosaic structures.&apos;

Jan 1, 1935

By R. W. Smith, R. W. M. Lai

Although several recent papers have shown that equilibrium contact angle in dodecylamine solution-quartz systems can often be directly correlated with flotation behavior, it appears that under conditions of relatively high amine strength and pH such a correlation can&apos;t be made. Under these conditions, when there are precipitated amine dipoles present, it appears that a dynamic contact angle formed immediately after introduction of fresh gas bubbles into the system is also of importance. The dynamic angle decreases in magnitude as a function of time. Apparently the decrease is the result of changes in interfacial tensions (liquid-gas and solid-gas) as a function of time. Dynamic angles of the type described can&apos;t be observed in trimethyldodecylammonium chloride solution-quartz systems. Several recent papers1-3 have shown quite conclusively that contact angle data can often be correlated directly with flotation behavior in cationic surfactant solution-quartz systems. At the same time, Iwasaki, Cooke, and Colombo4 have shown data for a dodecylammonium chloride solution-goethite system where, in the vicinity of pH 12 and a collector concentration of 10" M, 100% flotation occurs when equilibrium contact angle appears to be zero. A clue to this discrepancy can be found in the work by smith2 who reported the occurrence of dynamic, time dependent, contact angles in a quartz-dodecyl-amine solution system at relatively high pH values and at surfactant concentrations greater than or equal to 10-4 M. It was found that under these conditions, if a fresh bubble was brought into contact with a properly conditioned and polished quartz surface, a large angle was obtained. The large angle, however, instantly started to diminish in magnitude, sometimes to a smaller stable angle and sometimes to its complete disappearance. Also, if the bubble was preconditioned for some minutes (or sometimes even seconds) in the same amine solution, the smaller or sometimes zero stable angle was obtained when the bubble was brought in contact with the quartz surface. One is immediately led to the thought that perhaps it is these dynamic angles when they exist, not stable angles, that are of primary importance in flotation. The present investigation attempts to further study the relationship between contact angle and flotation

Jan 1, 1967

By D. L. Wood, J. H. Westbrook

The tensile behaviors of the CsCl structure compound AgMg are extensively documented in terms of strain, strain rate, temperature, composition, and metallurgical processing treatment. The observations lend themselves to presentation in terns of three regimes of deformation behavior; 1) low temperatures where deformation is primarily by slip; 2) intermediate temperatures where the deformation mode is also slip but with the detailed behavior dominated by dislocation interactions with solute atoms; 3) high temperatures where defomation is primarily by diffusion controlled processes. Of all the material groups of potential interest as high-temperature structural materials, the inter-metallics have been the least studied, particularly with respect to their mechanical behavior. Moreover, the application and processing of intermetallics for uses which exploit their often unique physical properties have been impeded by a lack of understanding of their mechanical properties. Previous work in this area* has been largely *For a recent review, see Westbrook.&apos; exploratory, aimed on the one hand at the direct empirical development of materials of engineering utility and ,on the other at identification of the important parameters affecting the mechanical behavior of inter metallics. As a consequence, there has not been available, heretofore—for any inter-metallic—data, sufficient in extent or precision to provide an adequate phenomenological description of the effects of metallurgical variables on deformation behavior. Such documentation is prerequisite to intelligent application or processing design and is also necessary for testing present and future theoretical analyses of mechanical behavior. It was therefore an objective of the present investigation to document the deformation behavior of a simple ordered intermetallic over as wide a range as possible of all the usual metallurgical variables. The compound AgMg was chosen as the subject of this investigation because it met all of a group of desired criteria, namely: 1) congruent but moderate melting point; 2) simple crystal structure; 3) ordered structure persisting to the melting point; 4) broad solubilities for the component elements. The first and last criteria were expected to aid in the preparation of homogeneous single-phase specimens: the second and third to help simplify the

Jan 1, 1962

By Vladimir Vigdergauz, Elena Belogub, Dmitriy Makarov

The influence of supergene oxidation on physicochemical and technological properties of polysulfide ores was studied. Modeling and analysis of oxidation pyrite copper-zinc ore samples from the Valentorskoye deposit show that sulfide floatability is decreased by the longer-term oxidation. The treatment of oxidized samples by sulfuric acid in oxidative conditions and its impact on the elemental sulfur composition on the surface of sulfides was discussed. It is shown that an enhancement of the floatability of sulfides of oxidized polysulfide ores after leaching by sulfuric acid could be perspective for the developing of combining floatation-hydrometallurgical technology of the nonferrous metals recovery.

Jan 1, 2014

Jarrah Decline is currently the only underground operation at the Boddington Gold Mine, (BGM). The mine is located 120 km SE from Perth in WA, with mineralisation hosted within deeply weathered felsic and intermediate intrusions and volcanic rocks of the Saddleback Greenstone Belt (Morley and McBride,1995). Open cut operations commenced in April 1987 with a mill throughout of 3.OMtpa. A number of upgrades have since taken place, with the oxide material throughput currently milled at a rate of 7Mtpa. In 1992 a separate circuit, the supergene mill, was commissioned to treat copper material from the open cut and now ore from the Jarrah Decline. Current throughput in the supergene plant is 30,000 tonne per month, with a varied blend according to mill requirements. Total gold production from the Jarrah Decline in 1994 was 60,000 ounces from 90,000 tonne of ore.

Jan 1, 1990

By R. Pallini

The Franklin Research Center (FRO, a Division of The Franklin Institute was contracted by the U.S. Department of Energy to investigate the application of elastomeric materials for the purpose of smoothing loads on dragline thrust rollers. This report covers the design, fabrication, and demonstration of a portable- device for measuring roller circle track deviations and roller loadings. The results of this work are documented in this report. During December 1981, a field test group visited the Falkirk Mine, Underwood, North Dakota for the purpose of demonstrating the use of the designed and built device. The data collected indicates the practicality and usefulness of such a device for determining actual dragline roller circle roller loads, while the dragline is in service. The device was useful in determining roller load peaking that may be a contributing Factor in the premature failure of these thrust rollers. The device could be used for field evaluation of elastomeric cushioning materials used to eliminate these load peaks.

Jan 1, 1982

By Robert W. Hunt

HAVING devoted considerable time to the investigation of the Clapp-Griffiths converter and the metal produced in it, it may perhaps be of interest to the Institute to learn the conclusions which I have formed. Of course, it is well known that the stationary converter of small size is the very oldest type of vessel used in the pneumatic process. Hence it will be only necessary to call your attention to the points which are special features of the Clapp-Griffiths. This converter has a slag tap-hole, situated at such a height in relation to the metal under treatment that, when the cinder is formed and boils up as the blow progresses, it can run off and thus be removed from contact with the iron, and will also be out of the way when the decarbonized metal is tapped into the casting ladle and the manganiferous alloy added. The manner of shutting off the blast, when the process is completed and the metal is being tapped, is another distinctive feature. The tuyeres are situated around the sides of the vessel, and enter the interior some little distance above the bottom; they are provided with plugs through the centers of which there are small openings. When the blow is completed, these plugs are forced forward into the outer orifices of the tuyeres, thus shutting off the blast, excepting the small quantity&apos; entering through the passages named. While this is sufficient to keep the metal from running into the tuyeres, it reduces to the minimum the action of the blast while the metal is being tapped. Of course, this is of great importance, as in an ordinary stationary converter any delay in getting open the tap-hole means overblowing, and even while the first part of the charge is running out the oxidation is in frill force. Duplicate or movable bottoms are used, thus more than doubling the possible output of the plant. The pressure of&apos; blast is quite light, never ex-

Jan 1, 1885

By J. P. Witherow

The Clapp and Griffiths steel-process may be considered a pneumatic system, similar to the Bessemer, with the difference that the converter is fixed or non-tilting, and that the blast is introduced around the lower section of the converter instead of through its bottom. Mr. Griffiths was engineer-in-chief of the Gilchrist & Thomas basic dephosphorizing process during all the time those gentlemen were experimenting and working up their system, as Mr. G. communicated to me. After separating from these gentlemen, he began developing the present Clapp and Griffiths type of converter. Dr. Clapp, of Nantyglow, Monmouthshire, was a prominent physician in a large iron district. Previous to his association with Mr. Griffiths, he took out some patents on a process of his own for the manufacture of steel, which patents stood in Mr. Griffiths&apos; way; hence the consolidation. Early in the summer of 1883, my attention was called to the experiments of Messrs. Clapp & Griffiths in Great Britain by a friend who had just returned from England. Later in that summer I went to Newport, on the border of Wales, where I met Messrs. Clapp and Griffiths and their friends. After visiting two small converters of their type which were in operation at different works, and spending a few days in the iron-districts of Wales, I went to London, where I met my friend Henry W. Oliver, Jr., who had already heard of the new steel-process. We decided to revisit Wales and examine more fully the process, more especially that Mr. Oliver might have the opportunity of coming practically in contact with the men and die process himself, so that his judgment might not be influenced by my sanguine feelings. On

Jan 1, 1885

When a mine decides to construct surface structures close to, or on undermined ground, it is required in terms of the regulations of the Mine Health and Safety Act to obtain permission from the Department of Minerals and Energy (DME). Apart from the legal requirements, the stability of the structures is crucial as damage to the structures due to surface movements could result in loss in life, equipment and/or production. This paper deals with the rock engineering aspects of a study that was conducted on one of the chrome mines in the Bushveld Complex (BC) involving the construction of plant structures on shallow undermined ground. The paper addresses the legal requirements and guidelines regarding ground stability of surface structures placed on undermined ground and the assessment of the undermined area with regard to the following: ?sources of potentially damaging surface movements ?safe mining spans ?stability of the pillars ?effect of the loading of plant structures on underground stability. Due to the irregular layout and geometry of the pillars in conjunction with a changing surface topography, numerical analysis and not the conventional tributary area theory was used to determine the imposed loads on the pillars. In order to subject the plant structures to minimum movement, the plant should be located in areas where the pillars would remain stable, the elastic deformation of the hanging wall is minimized and hanging wall failure extending to surface is unlikely to occur. The study indicates that although the depth of undermining is shallow (between 27 m and 60 m), potential damaging surface movements are not anticipated due to the stability of the pillars, competent nature of the overlying strata and negligible effect of the plant structure loading on the underground stability.

Jan 1, 2004