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By Z. Zhang

Aluminum boron carbide particulate reinforced composites have found new applications in nuclear industry due to their special capability to capture neutrons, Recently, Alcan successfully developed a liquid metal mixing process to fabricate Al¬B4C metal matrix composite instead of powder metallurgical technology. In the process, titanium is added into the composites to control interactions between boron carbide particulates and aluminum matrix, To understand the effects of titanium on the composites, the solidification microstructure of Al-16%B4C without or with titanium was examined by optical and electron microscopes. The results show that titanium can improve the uniformity of the particulate distribution within aluminum matrix if the titanium content in the composites is more than 0,5%, Furthermore, it is found that the layer with rich titanium on the surface of the particulates can limit the formation of AlB2 type compounds, which may greatly deteriorate the fluidity of the composites, In addition, it is also found that the amount of the reaction products in the composites increases with the increase of holding time. However, the rate of the increase is mitigated by the increase of the content of titanium in the composites. Besides, a procedure was proposed and implemented for the evaluation of uniformity of particulate distribution within aluminum matrix.

Jan 1, 2005

By W M. Gilchrist

This paper gives an estimation of the future requirements of the western world in relation to energy re-sources. It then goes on to outline the role that atomic power -with its basic raw material, uranium -will play in supplying these energy requirements. Canada's position in this picture is covered, and some interesting forecasts are made. Introduction I T is possible that the following remarks will appear to have more to do with power than uranium. However, to fully comprehend what is in store for the Canadian uranium mining industry, we must be able to estimate the potential requirement, and, to do this satisfactorily, a thorough understanding of the circumstances that will give rise to that demand is necessary. The growing need for electrical energy will play by far the major role, as large tonnages of uranium will be required for its generation. The nuclear weapon has, up to the present, comprised the major market for uranium.

Jan 1, 1964

By J. A. Chamberlain

DURING a recent trip across Canada and parts of the northern United States, the. writer examined some forty mine models. Construction -details and the uses to which the models were being put were outlined in a report to Eldorado Mining and Refining, Limited, and a specific model was proposed on the basis of the Company's particular needs at their Beaverlodge operation. It was felt, however, that portions of the report would be of some value to anyone contemplating building a mine model. For this reason, a synopsis of some of the more important aspects of the problem is presented here, together with a suggested model type that appears to have wide application. Thanks are due not only to Eldorado for permission to publish the following material, but also to the many mine personnel across Canada who allowed the writer to examine their models and gave freely of their time in discussion.

Jan 1, 1958

By R. O. Burt

"IntroductionThe introduction to this section on gravity concentration indicated the wide range of equipment types that exist for the concentration of minerals, in what is the broadest size range of any concentration process.The equipment described in this chapter includes jigs, tables and sHme plant equipment. In contrast to the equipment described in the two succeeding chapters, this range of equipment, in nearly every instance, superimposes a mechanical movement on the fluid motion to effect separation of the valuable mineral from the waste mineral. The motion may be vertical Gigs), reversing (tables), or rotary (slime plants): however, in common they ""dilate"" the bed of particles to allow preferential settlement of the heavier particles.Description of Process UnitsJiggingJigging is the sorting of different minerals by stratification, based on the movement of a bed of particles relative to a fluid in a vertical plane.The basic construction of a jig is shown in Figure 1. Essentially it consists of an open tank filled with a fluid, normally water, with a horizontal jig screen at the top and with a spigot in the ""hutch"", or bottom compartment, for removal of heavies. The jig beri consists of a layer of coarse heavy particles (ragging) on the jig screen. This ragging is of a specific gravity between that of the minerals it is intended to separate.In operation the bed is made fluid by a pulsating current of fluid to provide stratification. On the upward or pulsion stroke the bed of ragging and slurry is normally Hfted as a mass, then as velocity of the upcurrent decreases it dilates, loosening the whole mass. On the downward or suction stroke it closes slowly again. The ideal is to control this dilation of the bed of material so that the heavier and smaller particles penetrate the interstices of the bed, while the larger heavies fall under a condition akin to ""hindered"" settling."

Jan 1, 1989

By V. Labiouse, F. Orellana

"Hollow cylinder samples can be tested for both the characterization of rock properties and the physical modelling at reduced scale of engineering applications. Particularly, this type of experimental setup can be used to simulate different stress conditions around underground openings, as already developed in the petroleum engineering field e.g. to study the instabilities around deep wellbores during either drilling or the oil production phase. Some authors have also used this technique to successfully characterize the damaged zone around underground openings in the tunneling engineering field looking for an efficient design of their support.This article presents a new hollow cylinder testing device developed at the Rock Mechanics Laboratory of the Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland. It allows a full and independent control of the confining pressure and pore water pressure conditions at both the inner and outer boundaries of Thick-Walled Hollow Cylindrical samples. In order to mimicking a tunnel excavation in a porous rock mass, after initial recovery of the in-situ stress and pore water pressure, the hollow cylinders are subjected to a decrease in the internal confining pressure. Moreover, X-Ray Computed Tomography scans of the specimens are performed through the testing cell before and after the mechanical unloading to monitor the displacements undergone and the sample damage. The equipment, testing procedure and data analysis techniques are briefly presented in the paper.The good performance of the apparatus has already been checked on weak rock specimens, among others on Boom and Opalinus Clay samples. In many configurations, the mechanical unloading is found to induce a Damaged Zone (DZ) around the central hole. Its geometry and extent show a great similarity with in-situ observations around tunnels driven in the Boom and Opalinus Clay formations. Such similarities contribute to increase confidence in the understanding and modelling of the ongoing processes."

Jan 1, 2015

By PAULL. BROUGHTON

Commercial deposits of sodium sulphate are harvested from alkaline lakes that are widespread throughout semi-arid southern Saskatchewan and adjacent southeastern A lberta. Concentration of sodium sulphate occurs in undrained basins under semi-arid conditions. Precipitation runoff from land adjacen1 to 1hese basins leaches 1he mineral from the soils and carries it in solu1ion 10 the basins. The process may be largely subsurface, wherein spring seeps feed basins associated with buried (preg/acial) river valleys. Evapora1ion during summer concentrates salts in the brines, and chilling of water below sa/Uration poin1 during win1er resu//s in deposi1ion of sodium sulpha1e (mirabili1e) crystals on lake bo//oms. Sodium su/pha1e, commercially known as sa/1 cake, ranks second only 10 po1ash in cen1ral-wes1ern Canada's nonme1allic mineral production. // is recovered from su,face brines, directly from intermittenl salt beds, and, until recently, by solution mining of shallow subswface deposits. Sodium sulphate is extrac1ed from seven alkaline lakes and sail f/a1s in Saska1chewan and one in Alberta. Annual produc1ion is approxima1e/y a halfmillion tonnes. Manufacture of kraft paper is the mos1 significanl marke1 for salt cake, but addi1ional quantifies are used in the glass and detergent manufac1uring indus1ries.

Jan 1, 1984

By Ben Sheneider

AT THE Flin Flon plant of the Hudson Bay Mining and Smelting Co., Limited there are two types of multiple hearth furnaces used in the roasting of sulphides. This pa-per will deal primarily with the wedge-type furnace in the roasting of zinc concentrates. The other furnace, the Nichols-Herroshoff type, is used in the copper smelter and is described in the papers given by (1) J. H. Ambrose in 1935 and (2) R. E. Mast and G. H. Kent in 1954. The design and operation of these roasting furnaces at the present time is essentially the same as given in the write-up in 1954. No at-tempt will be made here to describe these furnaces, except to mention that there are five Nichols-Herreshoff multiple-hearth furnaces, four of which are used to roast a dried mixture of copper concentrate, zinc plant residue, and flux, before this material is fed to the reverberatory furnace.

Jan 1, 1961

ABSTRACT The inevitable uncertainty in modelling spatial variables decreases as more data become available. This reduction depends on the properties of the variable being modelled. Spatially continuous variables show less uncertainty for a given spacing than erratic variables. A geostatistical simulation based approach is developed to quantify the relationship between uncertainty and data spacing. Reference realizations are sampled to condition additional realizations and quantify uncertainty. The procedure is automated, making it straightforward to consider sensitivity and different geological domains. A case study of the relationship between uncertainty and data spacing for net oil sands thickness data from northern Alberta is presented. _ KEYWORDS Simulation, Sampling,

Jan 1, 2013

By A. J. Baer

"DEFINITION OF THE REGION AND ITS BOUNDARIESTHE EXPOSED PART OF THE GRENVILLE PROVINCE is the southeastern part of the Canadian Shield, characterized by crystalline rocks with K-Ar ages of about 1,000 million years. Its Canadian portion is bounded on the southwest by Georgian Bay •and by Paleozoic sediments south of a line passing through Orillia and Kingston, on the southeast by the St. Lawrence River valley and the north shore of the Gulf of the St. Lawrence, on the east by the coast of Labrador and on the northwest by the Grenville front, a linear tec-tonic feature that is a metamorphic transition zone and/or a fault. Rocks located to the southeast of the front have younger K-Ar radiom€tric ages than rocks located to the northwest of it.The region is formed of complexly deformed and highly metamorphosed crystalline rocks and in part differs from other areas of the Canadian Shield by the presence of large amounts of crystalline limestone and bodies of anorthosite."

Jan 1, 1970

By Mauro Chiesa

A. New Dictionary, Since 2007/8 Traditional concept of ?cycle? is dead A dearth of projects AND good metal prices suggests otherwise In a depletion-business, good times for any greenfields in 2-3 yrs! ?Balance? sheet means quality assets = quality capital So, de-risk the assets, and ration the capital ?Replacement costs > historical costs ?Discounted assets depleting; replacement costs need self-financing (FCF) ?Public-sector slows permits, avoids assets and wants more of FCF ?Capital ?markets? are now ?market fragments? ..and? ??Shareholder? has changed from ?growth? to ?income + performance? ?Higher search costs, higher capital costs and higher cost of capital

May 1, 2013

By Kevin J. Melong

"Redpath Canada Limited and joint venture partner Thyssen Mining and Construction Canada have recently completed the sinking of the Scissors Creek service in Saskatchewan through its joint owned company, Associated Mining Construction (AMC). The Scissors Creek service shaft was sunk at Nutrien’s Rocanville mine. The following paper outlines the shaft sinking plant and the methodology related to sinking and shaft lining. KEYWORDS Hydraulic shaft jumbo, Hydraulic shaft mucker, Potash shaft sinking, Shaft lining, Sinking galloway INTRODUCTION The sinking and lining of shafts at mines to access mineral deposits has always been one of the great mining challenges for owners, engineers and contractors. Over the course of history in Canadian mining, the sinking of potash shafts through the notorious Blairmore formation of Saskatchewan has proved to be some of the most challenging shaft sinking projects on record. There is no doubt that today’s shaft sinking business demands the utmost in safety performance while delivering projects within schedule and budget. Given these requisites, Redpath and TMCC (executed under the joint venture company, Associated Mining Construction or AMC), were taxed with developing the shaft sinking system to deliver this program in the safest and cost effective manner, with due regard to schedule and quality. Traditionally the potash shafts sunk in Saskatchewan involved a significant level of manual labour, owing to the methodology of excavation by means of chipping the frozen shaft sections with hand held pneumatic machines, and manually placing tubbing segments or steel liners of the shaft lining system. Most certainly, the AMC team wanted to make a step change from those earlier sinking programs and develop systems for sinking this potash shaft that removed the high level of manual work, thus making this project inherently safer, while endeavoring to sink more efficiently. With that in mind, the team embarked on a design program to improve its overall shaft sinking systems without the requirement for excessive capital and methodology flexibility to adapt to potential changing conditions expected to be encountered during shaft sinking. This was especially important should the new approach be met with less than expected success, and retrofitting of the system was required. The concepts were developed to provide for a much improved work environment, while easing the manual labour burden on the workers with innovative equipment and approach to the work."

Jan 1, 2019

By Xu Wang, Yizhe Zhang, Yangge Zhu, Xiao’ou Xia, Fangming Liu

"The progress of lean magnetite preconcentration in China was introduced in this paper, such as using coarse crushing to reject tailings, and multistage grinding, multistage magnetic separation. The applications of “more crushing and less grinding” process and equipment in lean magnetite preconcentration could reduce production costs effectively. The related analysis and study on concrete cases were carried out in this paper.INTRODUCTIONIn the case of the slowdown and weak recovery in the global economy, bulk commodity prices fell sharply in 2015. Take iron ore's prices for example, about 60% grade iron ore's import prices in China from about $65 per ton at the beginning of 2015 fell to about $42 per ton in the end of the year, down by about 35%. But iron ore resources are non-renewable resources, with the continuous development and utilization of mineral resources, high grade iron ore resources will be exhausted gradually. Accompanying with the economic recovery iron ore prices after this fall is bound to return to its value to maintain a high level.The development and utilization of resources is gradually turning to the low grade iron ore. Restricted by technical development level and disadvantages of lean iron ore resources, the cost of utilization lean iron ore resources is relatively high. Making full use of their rich lean ore resources has become many countries' important strategy to get rid of dependence on foreign countries' ore. Over the years with the development and progress of lean magnetite mineral processing technology in China, the production number of concentrator has been greatly improved.As the world's largest steel producer and consumer countries, ensuring a stable and continuous supply of iron ore is particularly important for the healthy development of China's iron and steel industry. Chinese iron ore production and import data in recent years are showed in Table 1.With the expansion of iron and steel production, iron ore demand has also been a phenomenal growth. Taking 2013 for example, China's crude steel production is about 780 million tons in 2013, accounting for about half of the world's total output of crude steel. At the same time, China is also the first major iron ore import countries whose iron ore imports in 2013 was about 820 million tons, an increase of about 10%. The degree of external dependence is very high. In some years, the cost of China's iron ore imports was even more than $100 billion, and second only to oil’s import cost in all bulk commodities."

Jan 1, 2016

By E. Ghali

"Corrosion of support system components (e.g., bolts, mesh, plates) is a safety and economic concern in underground mines. This paper reports the results of a five-year study wherein corrosion coupons were installed at select locations in participating mines, recovered at regular intervals, analyzed for signs of corrosion, and tested to quantify loss in capacity. Complementary tests were conducted on recovered mesh and friction bolt specimens. The data provide insights into contributing factors for support systems corrosion, which aid in the selection of appropriate support strategies and reliable assessment of the useful life and need for rehabilitation of a support system.RÉSUMÉ La corrosion des composantes des systèmes de soutien (p. ex. boulons, grillages et plaques) est une préoccupation économique et de sécurité dans les mines souterraines. Cet article présente les résultats d’une étude de cinq ans pendant laquelle des coupons de corrosion ont été installés à des endroits spécifiques dans les mines participantes; ces coupons ont été retirés à des intervalles réguliers, analysés pour des signes de corrosion et mis à l’épreuve pour quantifier la perte de capacité. Des essais complémentaires ont été effectués sur les grillages récupérés et sur les échantillons de boulons d’ancrage. Les données aident à comprendre les facteurs qui contribuent à la corrosion des systèmes de soutien, ce qui est utile dans le choix de stratégies appropriées de soutien et pour une évaluation fiable de la durée de vie utile et du besoin de remise en état d’un système de soutien."

Jan 1, 2015

By Jacques Nantel

"The molybdenite property of Brynnor Mines Limited, Boss Mountain Division (wholly-owned subsidiary of Noranda Mines Limited), is situated approximately 360 miles northeast of Vancouver on the east slope of Takom-kane mountain in British Columbia's Cariboo District. Orebodies at the deposit fall into two categories; quartz breccia, and veins and stringers. The development of the breccia ore zone was started in June, 1964. The bulk of the ore is being mined from the stringer ore zone. The ore-body has been divided into 100-foot stopes and pillars. A sub-level blasthole method is used and the broken ore is handled in drawpoints and scram drifts. The development, drilling, blasting and handling of the ore are reviewed. The future pillar recovery operation is also analysed. The paper is also concerned with a scheduled shaft sinking program."

Jan 1, 1970

By N. E. Izatt

Molecular recognition technology (MRT) has a wide range of applications in the hydrometallurgical and chemical processing industries for the selective removal of iron as well as various other impurities from a variety of streams, including aqueous solutions through a wide pH range, as well as organic solutions. An example of a commercial application is provided for the removal of iron from an aluminum chlorohydrate stream. In this example, MRT has a selectivity for iron relative to aluminum which is significantly higher than that of ion exchange resins. A discussion of MRT capabilities for other impurities and streams is also provided.

Jan 1, 2006

By C. G. Anderson

As the global demand for copper and gold steadily increases and the need for environmentally sound processing also grows, successful hydrometallurgical treatment of enargite (Cu3AsS4) concentrates has come to the forefront. This type of concentrate contains considerable arsenic so that successful arsenic fixation, for example as scorodite, is of the essence. This paper outlines the successful application of low temperature and low pressure nitrogen species catalyzed (NSC) hydrometallurgical pressure oxidation of enargite concentrates. The successful stabilization of the arsenic as an iron arsenate compound is discussed. Also, the use of experimental design software is highlighted as a process application and optimization tool.

Jan 1, 2006

By W. Hawker, A. M. Ivana

"Pressure oxidation is used to liberate gold from refractory sulphide ore and concentrates with over fifteen autoclaves in operation. Despite the importance of pressure oxidation, the autoclave chemistry and chemical thermodynamics are not well established. For example, there is no consensus on aqueous iron speciation or stability of jarosite phases. Additionally, there remains questions about basic ferric sulphate formation and stability. In addition to a review of the current state of knowledge, a methodology to study the ferric precipitation reaction and relate the results to chemical thermodynamic predictions is presented which will be used to accurately define the phase boundaries of the iron precipitates in the future (hematite, jarosite and basic ferric sulphate).INTRODUCTION With declining availability of orebodies that respond to simple leaching conditions, pressure oxidation has become a prevalent technology to liberate gold locked in sulphide mineral matrices. Gold pressure oxidation was established 32 years ago, with McLaughlin being the first facility in 1985 (Thomas & Pearson, 2016). Pressure oxidation is carried out at elevated temperatures ranging from 180 to 240°C as shown in the summary of operations in Table 1 (Ruonala et al., 2016; Fleming, 2010).A considerable amount of research has been done to study iron solubility and precipitation under autoclave conditions (Tozawa & Sasaki, 1986; Umetsu et al., 1977; Sasaki et al., 1993; Fleuriault, 2016; Cheng & Demopoulos, 2004; Papangelakis et al., 1994; Yue et al., 2003). These reports provide a description of the process chemistry and iron behaviour in the autoclave. However, there remain questions about the type and stability of aqueous species and solid phases. This detailed information is required to build a robust chemical thermodynamic model of the system, allowing for equilibrium and kinetic reaction limitations to be discerned."

Jan 1, 2017

By Stephen Mullowney

Outline ? Setting the stage ? Deal activity ? Q1 2013 update ? Key deal sectors ? Deals by geography ? Outlook for 2013 Key Observations 2012 ? Major retreat in M&A activity ? Glencore-Xstrata deal dwarfs all other deals ? Gold & copper dominate deal activity

May 1, 2013

By F. McGravie, S. T. Solinski, W. W. Robertson

During this, the Centennial year of the discovery of the Hall-Heroult process, it seems appropriate to review some of the developments which have taken place in Canada and to explain why it has become an important world centre for the production of primary aluminum. For many years after it was recognized that the element aluminum existed, scientists were frustrated in their efforts to isolate it. In the early 1800s H. C. Oersted and Frederick Woehler prepared small quantities sufficient to measure some of the physical properties. A quasi-commercial process involving reduction with metallic sodium was developed by the French scientist H. St. Claire Deville in 1855 but the cost was very high ($30. 00 per kg). It was not until 1886 that Charles Martin Hall in the United States and P.L.T. Heroult in France, more or less simultaneously but completely independently, discovered the process which is essentially that in use today. Some of the early pioneers in the industry quickly recognized the potential of the hydro-electric resources in Canada as economic energy suppliers for aluminum production. The first commercial production in Canada was in Shawinigan, Quebec in 1901, only 15 years after the process was discovered. Subsequently operating plants were established at nine different locations in Canada (Quebec and British Columbia) (Table 1). Operations continue today in all locations except one (La Tuque). The table shows present plant capacity which for the older plants was reached in an evolutionary manner including replacement of obsolete capacity or upgrading and modernization of existing designs.

Jan 1, 1999

By J. S. DeLury

Introduction The problems of metallogenesis are largely related to those concerning the origin of igneous rocks, which, in turn, are involved with the question of crustal mechanics. Many ore-bodies are genetically related to associated intrusive and there is an equally close association apparent between igneous intrusion and crustal deformation. The problem of ore-deposition is concerned, therefore, with the fundamental problems of geology. For a long time speculations regarding crustal movements rested largely on the contraction theory and its associated conceptions. Vertical movements were considered to be all important and horizontal movements secondary to them. Magmas were pictured as rising more or less vertically in the crust and were believed to form in vertically disposed magma-chambers or reservoirs. The principle of magmatic differentiation seemed to offer the best explanation of the origin and association of diverse rock types and it seemed also to require the existence of quiescent magma-chambers for the admittedly slow process of differentiation. Accumulating evidence of the importance of horizontal movement in the crust, has, along with other considerations, discredited the contraction hypothesis and many of the inferences that go with it. The same evidence may require some change in the prevailing conception of the origin of the various types of igneous rock and of the mechanics of intrusion. Geologists are now at sea concerning some of the vital and fundamental problems of the crust, and the field is open for speculation. The writer is developing a hypothesis which seems to permit an explanation and? a correlation of earth structures and phenomena. If it rests on a firm foundation, the hypothesis, because it is fundamental, is certain to have a profound bearing on the problems of economic geology. It is for this reason that an outline of the hypothesis is offered at this time. Only a few of its economic bearings are foreseen at this time and these will be indicated.

Jan 1, 1932