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By B. Arsenault

Aluminum coatings can provide galvanic cathodic protection for several metals and alloys, In order to be a suitable protective solution on structural components, the mechanical integrity of the component must be preserved, In particular, fatigue properties are a challenge for thermal-spray protective coatings on mechanical structures, To address the issue of the fatigue integrity of 7075 aluminum alloy with an arc-sprayed protective coating, different surface preparations prior to arc spraying were considered, In the present work, a feasibility study was performed using laser ablation as a surface-preparation technique before or during arc spraying of coatings, This was collaborative effort between the LERMPS laboratory in France, the National Research Council Canada and the Royal Military College of Canada, Both fatigue and adhesive properties of aluminum coatings were evaluated in relation to substrate-surface-preparation techniques including laser ablation (Protal® process), grit blasting and shot peening. Results indicate that a combination of key conditions, including the use of nitrogen as the arc spray gas, shot peening, and proper laser energy density for ablation, provide high fatigue resistance of metallic coated 7075 alloy substrates. Specimens prepared under these conditions show a similar fatigue resistance to uncoated substrates.

Jan 1, 2005

By Harry Siewert

"The commissioning of the 4th concentrator (C4) at Freeport Indonesia in early 1998 increased total mill throughput from 130k to 230k tonnes per day. The C4 flowsheet consists of a single 38 ft diameter SAG mill, four 24 ft diameter ball mills followed by four banks of 4,500 ft3 WEMCO flotation cells.The design of the C4 rougher flotation circuit was based on the expectation that the copper and gold recoveries achieved with the 4500 ft3 flotation cells would be equivalent to or better than that achieved with the 3,000 ft3 flotation cells in the 3rd concentrator (C3) rougher circuit. This assumption was due to the fact that the C4 flotation feed size would be less than 15% +212 microns compared to the C3 rougher flotation feed size of less than 23% +212 microns. By mid 1998 it had become apparent that the C4 rougher flotation copper and gold recoveries were below those predicted.In order to determine the cause of the lower recoveries, stage by stage rougher flotation surveys were performed in all four concentrators. The results of the surveys showed that the C4 rougher flotation circuit had a lower recovery of +200 micron material than that achieved in the C 1, C2 and C3 concentrators. Through mineralogical analysis, it was determined that a majority of the copper contained in the +200 micron fractions was liberated and recoverable. This paper describes the steps taken to increase coarse particle recovery, overall plant recovery and the results achieved."

Jan 1, 2001

By Edgar Stansfield

Introduction First, I should define more closely the vague term 'recent work' that appears in the title of this paper. Following the period of depression that was an aftermath of the first Great War, the Research Council of, Alberta carried on for ten years without a Council and without a financial yote by the Legislature. In November, 1942, a new Council was formed, under the chairmanship of the Hon. N. E. Tanner, Minister of Lands and Mines, and a vote was granted by the Legislature early in 1943. By 'recent work', I mean work during the present regime. The Council is now going full steam ahead, or would be if it could get suitable technical assistance and required apparatus and materials. Lack of these has so far made unnecessary my responsibility for seeing that we do not exceed our estimates. The Annual Meeting of the Research Council will be held in November (1945), and at that meeting the programme of work for next year will be discussed. The present time is therefore the correct time for any of you who may have ideas as to work which might profitably be undertaken by the Council, to submit these ideas for consideration. I propose to discuss my subject under several headings, and to give enough of these to show that the Council has wide interests.

Jan 1, 1946

By S. E. Kesler, C. M. Moore, J. C. Van Loon

The possibility that chlorine and fluorine form complexes with ore metals, thereby having a strong effect on the mobility of these ore metals during late magmatic and hydrothermal processes, suggests that the abundance of chlorine and fluorine in igneous rocks could be used to distinguish intrusions that have generated ore deposits. The simplest and most economical measure of this chlorine and fluorine is the water-leachable chloride and fluoride that is released from fluid inclusions in the rock during crushing of the sample. In order to evaluate the possible use of this technique, measurements of water-leachable chloride and fluoride were made with selective ion electrodes on samples from nine intrusive complexes. There does not appear to be any simple relation between the abundance of chloride and the presence of mineralization. Fluoride values in mineralized intrusions appear to be higher than those in barren intrusions.

Jan 1, 1973

By Elmer Palmer

As part of the Goldcorp Inc growth plan Minera Peñasquito SA de CV has developed its polymetallic deposit with a large ?state of the art? concentrator to process lead and zinc ores. The plant consists of two grinding lines including 38ft diameter SAG mills and 24ft diameter ball mills. During mid to late 2009 concentrator commissioning activities commenced. First concentrates were produced in October 2009 and now the plant is meeting its design basis of 65,000 mtpd per line. This paper describes the design and operational experience to date for its grinding circuit design, together with the recently commissioned HPGR crushing circuit.

Jan 1, 2012

By Kenneth M. Haley

THE development of Reserve Mining Company's pelletizing practices began in 1949 in a pilot plant located at Ashland, Kentucky. Three years later the participating companies -Armco Steel Corporation, Cleveland Cliffs Iron Mining Company and Republic Steel Corporation concluded the work and the small plant was shut down. Oglebay Norton and Company was the operating manager and Armco Steel Corporation furnished labor and services. Arthur G. McKee and Company were the designers and constructors. The equipment flow sheet that was employed in that pilot operation is shown in Figure 1. This was Reserve's first step from the laboratory work per-formed by the Mines Experiment Station of the University of Minnesota in developing a commercial operation. The plant used New York state concentrate, purchased from Jones and Laughlin Steel Corporation's Benson Mine. This concentrate, minus 14 mesh, 64.3 per cent Fe, 5.7 per cent Si02, was processed at Ashland to 80 per cent minus 325 mesh in conventional ball mill, classifier, thickener, filtering

Jan 1, 1961

By Euler De Souza, J. Daniel Stinnette, Julian Varaschin

"This paper outlines some of the factors that affect the airflow required for the ventilation of modern diesel-powered equipment and of electric equipment and examines how they can be applied in determining reasonable ventilation rates for Tier IV compliant diesel equipment and for electric equipment operating in mining environments. Airflow calculations for modern diesel-powered equipment and for electric equipment are more complex and must be based on a combination of factors that are unique to each mine. Methodologies for ventilation rate determinations for each case are proposed in this paper.INTRODUCTIONTraditionally, airflow requirements for production and support equipment operating in underground mines have been determined by multiplying the vehicle power by a ventilation rate that was either mandated by regulations or determined empirically from known quantities. However, in light of the drastic reductions to diesel equipment emissions mandated by the US EPA Tier IV and EURO Stage 4 regulations, there is still a great deal of uncertainty in the underground mining industry among those responsible for the ventilation of planned new mines or the expansion of current mines. The question remains, what ventilation rates should the ventilation system designer apply for modern diesel equipment?Also, given the ongoing development of grid/battery-electric equipment and active construction of fully electric mines, it has become critical to determine adequate airflow rates per brake kilowatt of electric engine power. One of the most important criteria for determining ventilation rates for electric equipment is the amount of heat they generate, as this is the most significant emission produced by electric equipment (which do not produce exhaust gases or particulates). Therefore, ventilation rates required to dissipate heat from electric equipment must be suitably determined for all electric vehicle fleets operating in underground mines."

Jan 1, 2019

By J. E. Nesset

Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right 'strength' is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry may also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.

Jan 1, 2009

By Technische Universität Braunschweig, K. Saksl, J. Furste, P. Eschenbacher, F. Brunke, D. Wolter, M. Kohnke, C. Siemers, J. Kiese, M. Schlemminger

"In general, titanium alloys combine outstanding mechanical properties with corrosion resistance and biocompatibility and are, therefore, used in many challenging applications. Nevertheless, for special products, well-tailored properties are required which might not be achievable by a specific design so that new or modified alloys are needed. In this overview paper, alloy development strategies performed at the Institute for Materials of the Technische Universitat Braunschweig are discussed at different examples, namely, (1) oxidation-resistant, microstructural-stabilized and cold-workable alloys for exhaust applications, (2) aluminum- and vanadium-free, medium-strength and cold-workable alloys for implants and osteosynthesis applications and (3) free-machining alloys by the addition of particles with low melting points for non-safety critical light-weight constructions to replace heavier steels, e.g. in automotive applications. A special focus is set on the alloy development techniques and the analyses carried out to achieve well-balanced properties by the optimization of the alloy compositions. INTRODUCTIONTitanium belongs to the allotropic metals and can therefore exist in two different equilibrium lattice modifications. Pure titanium crystallizes at 1668°C in a body centered cubic (bcc) structure called ?- titanium which at 882°C transforms to a hexagonal close packed structure (hcp), the a-titanium. A martensitic ?-to-a-transformation is possible at large cooling rates. This thermally induced hexagonal martensite is called the a'-phase. The transformation temperature named ?-transus-temperature (T ?) can be influenced by alloying elements (Peters & Leyens, 2002).For titanium alloy production typical alloying elements are aluminum (Al) and oxygen (O), both a-stabilizers shifting the ?-transus temperature to higher temperatures, whereas tin (Sn) and zirconium (Zr) only show a limited influence on the ?-transus temperature. The ?-stabilizing elements are subdivided into two groups: Niobium (Nb), molybdenum (Mo) and vanadium (V) stabilize the ?-phase between the melting point and room temperature and are therefore called isomorphous -stabilizers. Elements like copper (Cu), iron (Fe) or silicon (Si) also stabilize the ?-phase to lower temperatures but undergo a eutectoid reaction during cooling. ?-titanium then dissociates to a-titanium and an intermetallic compound. Consequently, these elements are called eutectoid ?-stabilizers (Boyer, Welsh & Collings, 1994)."

Jan 1, 2016

By Nick D. Rose

The Dy deposit is a 21 Mt Pb-Zn-Ag-Au SEDEX-type massive sulphide resource located in the Anvil District, Faro, Yukon. This relatively unexplored orebody lies at a depth of 480 to 920m below surface, dips 20 to 35o and comprises vertical ore thicknesses of 3 to 28m at a 9% Pb + Zn cut-off grade. The deposit has been tested at depth with 63 surface diamond drillholes, but has not yet been explored or developed by underground means. Over the past decade, pre-feasibility investigations were conducted for two separate owners of the property to determine the economic viability of developing an underground mine at Dy. Following these previous studies an assessment was undertaken between 1998 and 2000 to further investigate geotechnical considerations for underground mining. The results and conclusions drawn from this study provide direction for possible future exploration at Dy.

May 1, 2002

By S. C. Ellis

THE bituminous sand of northern Alberta has already an extensive literature, and most of the reports dealing with the subject are still available (see Selected Bibliography at end of paper). A phenomenon so striking and, as regards its extent, so unique, as the deposit in the vicinity of McMurray settlement could not fail to attract the notice of the early explorers, and we find references to it as far back as the latter part of the eighteenth century. However, scarcely a thought had been bestowed upon the possible economic value of minerals in the the remote northern parts of Canada before the second decade of the present century, and practically no detailed mapping had been done north of the town of Athabaska. The late Wm. Ogilvie made a track survey of Athabaska river in 1884, and surveys of certain lines-including the 23rd base line-had been completed by 1911. Between this base line and lake Athabaska, nothing had been attempted. Actually, no definite information at all was available regarding the character and extent of the bituminous sand when, in the earl y summer of 1913, a reconnaissance party set out from Athabaska for McMurray. At that period, the journey was made in summer by scow or canoe. No telegraph line had been laid, and a casual mail service by canoe or dog team once in three months formed the only means of communication with the outside world. The investigation has begun by the Mines Branch was continued during several subsequent years. The sand deposits were studied and sampled, the bi rumen was extracted from the sand and studied chemically and physically, and the economic significance of the deposit was given exhaustive study.

Jan 1, 1937

By R. Heikkilä

The utilization of Building Information Modeling (BIM) and model based 3-D control of work machines have increased a lot in new road construction in Finland as well as in other Nordic Countries. Up today, much less attention has been paid into the development of maintenance and rehabilitation processes. As a part of a large research and development program RYM PRE Infra FIN BIM in Finland, a focused research project of the BIM with experiments in total five (5) pilot projects has been performed. A main idea of the new BIM based process has been to utilize mobile laser scanning method for initial data acquirement, the use of novel 3-D analyze and modelling methods for point cloud processing, the use of new type optimization method for the planning of geometric and structural improvements needed for the existing uneven road surfaces, and further, through the creation of 3-D machine control models apply the newest 3- D machine control systems for continuous 3-D control of practical construction work using milling machine and asphalt paver. Finally, an evaluation is made between the new process model and the traditional way of working.

Aug 1, 2013

By H. W. Smith, N. Ichiyen

A convenient method for the calculation of metallurgical balances, based on statistical treatment of all available data, is presented. An error analysis is included. Examples show the advantages of the method, and also that such balances are less precise than might be supposed.

Jan 1, 1973

By W. H. Zieman

"THIS IS THE THIRD of the consecutive Annual Forums on Grinding that were instituted by Mr. L. E. Djingheuzian in 1957. The first was on the subject of Ball Milling (Transactions, Volume LX, 1957) and the second on The N on-Cataracting Ball Mill (Trans-actions, Volume LXI, 1958). From the discussions at these forums it was evident that one of the most important factors affecting the efficiency of grinding is the shape of the liners. In order to make a study of liners in use, it was •decided to seek the co-operation of operators across the country by sending out questionnaires requesting basic information. Additionally, these operators were urged to set down briefly any pertinent information on the subject acquired through experience and experiments at their own particular plants. A compilation and analysis of these data were to form a basis for discussion at the Forum on Liners at the Annual Meeting in Montreal, April, 1959. The response of the milling fraternity to this solicitation was most gratifying, and clearly indicated the importance attached by the operators to the effect of liner design upon overall grinding performance."

Jan 1, 1959

By Shin-Kun Ryi

The world nowadays faces many challenges associated with excessive utilization of fossil, fuels, such as poor air quality and greenhouse gas emissions. Hydrogen appears to be an attractive alternative to the conventional, fossil, fuels with better energy efficiency and less environmental, impact. Pd and Pd-based alloy are the most often used membranes for hydrogen separation due to their superiority over other membranes. However, the stability of the commonly-used thin Pd-based composite membranes at high temperatures still, remains a big challenge. In this presentation, we will, report our progress on thin Pd-Ru alloy composite membrane by electroless plating high temperature applications.

Jan 1, 2010

By Y. Chengxian

Many factors about the HIC (hydrogen-induced cracking) resistance of pipelines are discussed in this paper. The main factors that influence the ability of HIC are environmental and material factors. The chemical compositions, non-metal inclusions and microstructure are discussed in detail, while a group of tests on HIC resistance are done according to varying C, S, Mn and P contents in pipeline steels, different experiment time and different strength to the coupon. It is concluded that decreasing the amount of C and S can obtain good HIC resistance; the test time has an effect on the different microstructure of X70; microstructure is the most sensitive factor for the initiation processes of HIC.

Jan 1, 2005

By P. Bakke

Following extensive R&D efforts, Hydro Magnesium has launched a new alloy series with remarkable combinations of properties. The AE alloy family is based on additions of aluminium and rare earth elements to control mechanical properties, including elevated temperature creep strength. By combining these alloying elements with manganese additions, high purity alloys with outstanding corrosion performance are defined. A basic philosophy behind the developments has been to simultaneously approach all the critical issues related to developing a commercial material. Apart from the obvious requirements for material properties, the critical issues relate to die casting performance, as well as alloy production, recycling and environmental compatibility. Some of the important elements related to alloy production and recycling are addressed in the present paper.

Jan 1, 2006

By G. M. Furnival

A PROGRAMME of structure drilling was commenced in the Southern Alberta Plains in June, 1943, for the purpose of determining the geological structure of the underlying sediments. More than 270 holes have been drilled throughout an area of some 1,800 square miles or 1,000,000 acres (see Figure 1). The Southern Plains of Alberta are covered by a mantle of glacial drift,' at places exceeding 200 feet in thickness. Only where this mantle has been dissected by deep drainage channels is bed-rock exposed to any great extent. Along such channels, surface geological mapping can be conducted to ad- vantage. Accordingly, geological mapping was commenced _in 1942 and continued each season to the present. To supplement this information, a survey of the water wells was carried on in conjunction with the mapping. However, to obtain more positive and evenly distributed structural control throughout the area as a whole and to define more adequately structural trends indicated by the preliminary mapping, it was necessary to resort to the use of drills to penetrate the glacial mantle. Various types of light drills are commonly used for this purpose and provide geological information in the form of drill cuttings, cores, drilling time rates, etc. Correlation of information is generally obtained through comparison of cored sections, drill cuttings, micro-fossils, and drilling time rates. However, in this case the holes were electrologged and correlations were made chiefly by comparison of such logs. The data so obtained is plotted and portrayed in the form of structure contour maps on recognizable stratigraphic horizons and in the form of isopach maps of the recognizable stratigraphic intervals penetrated in the holes. This method had not been widely used in Alberta previously and the technique employed was necessarily developed after the project began.

Jan 1, 1945

By A. Zarei-Hanzaki, O. Golmahalleh, S. M. H. Hosseini, H. Azizi-Alizamini

The main importance of acicular ferrite microstructures arises from their desired combination of mechanical properties in comparison with the bainite and ferrite-pearlite microstructures. Several factors affect the microstructural transition from bainite microstructure into the acicular ferrite one. As is well established any factor corrupting the prior austenitc grain boundaries nucleation potential, such as the thin layer of allotriomorph ferrite and the austenitc deformation inhomogenities may promote the acicular ferrite formation instead of bainite. Accordingly, this study deals with the effects of the aforementioned features on the acicular ferrite formation in low carbon microalloyed steel. The results indicate that the formation of strain-induced ferrite at the prior austenite grain boundaries accompanied by deformation inhomogenities in the austenite grains change the effectiveness of allotriomorph ferrite on acicular ferrite formation from active to inert one.

Jan 1, 2004

By Laura A. Sanders

Mineral scale formation is prevalent in numerous mining operations. Such scale formation can occur in the direct-contact heat exchangers ahead of an autoclave. In these heat exchangers, the incoming slurry comes into contact with steam in a stage-wise fashion, which is re-circulated from the downstream flash vessels to heat the slurry in stages ahead of the autoclave. Calcium sulfate scaling causes severe problems in mining operations where increased temperatures are involved due to rising temperatures promoting calcium sulfate scaling through a decreasing solubility. In a number of these operations, the scale formation can occur in the presence of mineral solids, where fine-grained charged particles are at concentrations in excess of 35%. Scale prevention is not difficult in standard aqueous systems; however, the presence of solids leads to significant deficiencies in the prevention of scale due to the adsorption of the polymer onto the charge solids instead of the polymer interaction with the scale. Therefore, a technical solution to prevent mineral scale build up occurring in presence of pulp slurry in mining operations is needed. Several novel antiscalant technologies were developed and evaluated which provided a substantial improvement in the scale prevention in such systems.

May 1, 2013