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By W. G. Worcester

IN the presentation of this paper to the Institute, three objects are in the mind of the writer: first, to set forth the close relation which, of necessity, exists between ceramics and the industrial minerals; second, to clarify the apparently hazy understanding which many have of ceramics in general; and lastly, of equal or even more importance, to stimulate a greater interest in the industrial minerals, especially in those used and required by the ceramic industries. While Canada is now producing in large quantities a fairly wide variety of the ceramic industrial minerals, there are some which are not known to occur in the Dominion. Hence it is to be desired that our geologists, prospectors, and others, while on field work, should be on the look out for commercial deposits of such minerals as diaspore, bauxite, ucts of a value in excess of $600,000,000, a figure which places ceramics as kyanite, massive topaz, and sillimanite. A find of any of these in quantity would prove of very great importance and value to the country as a whole. At this point it seems desirable to introduce formally the word ceramic or the plural of it, ceramics. In doing so it may be stated that the origin of the word dates far back in history in that it was derived in part from the Greek word Keramos, 'a potter' or 'pottery', which in turn has been traced back to an older Sanskrit root meaning 'to burn' or 'burned stuff', having reference, no doubt, to burned pottery or other clay wares; and the word was so used until near the close of the last century, when the world's first schools of ceramic engineering were established in the United States. The use of the term ceramics was then expanded to cover a much larger field the entire field of the silicate industries and products. At one time it was suggested by a limited number of ceramists that the term 'ceramic engineering' be changed to 'silicate engineering'. This proposal, however, gained little support and was soon abandoned.

Jan 1, 1945

By M. E. Hurst

Introduction Between 1903 and 1905, W. Mclnnis, of the Geological Survey of Canada, made a micrometer traverse of the Kawinogans (Crow) river from Kapkichegimaga lake to its junction with the Otoskwin river. He reported that a belt of Keewatin rocks, 1 to 4 miles wide, was exposed along the course of the river for 17 miles east of Kapkichegimaga lake. Prospectors and exploration companies paid little attention to the mineral possibilities of this belt until the summer of 1928 when, with the adoption of airplane transportation, the area became readily accessible. Within a short time widespread interest was aroused by the announcement of attractive finds, and a mild rush followed. During the winter months, hundreds of claims were staked on either side of Crow river for 12 miles east of Pickle lake. In the summer of 1929, much of this ground was systematically explored and a considerable amount of development work was done on the known deposits.

Jan 1, 1930

By S. Fahland, P. Vogel

"The Gorleben salt dome has been investigated since 1979 for its suitability as a repository for the disposal of high-level radioactive wastes. The geoscientific surface exploration was followed by underground exploration of the site beginning in 1983: underground excavation work included the sinking of two shafts from 1986 to 1994, the excavation of the infrastructure area and of drifts located in the first exploration area EB1 within the following years. The exploration was interrupted for ten years from 2000 to 2010 as part of a moratorium. After the expiry of the moratorium in March 2010, the geoscientific underground exploration at the Gorleben site was resumed. The investigations were interrupted again in autumn 2012 due to a political decision. The exploration programme included extensive geoscientific investigations: geological exploration, geophysical investigations, mining exploration and mining observation, laboratory tests, in-situ geotechnical measurements, geological modelling and numerical model calculations. To analyse and interpret the results of the in-situ measurements and mining observation geomechanical, thermal and thermo-mechanical model calculations were carried out. One of the main elements of the in-situ geotechnical investigations were high-resolution geothermal measurements performed in boreholes used for geological exploration and geotechnical tests.The geothermal measurements are used to evaluate several geotechnical findings, e. g. drift closure, rock deformation, stress change, and are completed by thermal model calculations to analyse and interpret the results of in-situ measurements and mining observation. The model calculations have been carried out using the special purpose JIFE code. To consider the whole exploration mine with the adjoining host rock as well as the successive excavation of drifts and boreholes in detail a three-dimensional finite-element model was developed. The model calculations are used to analyse the cooling-off of the surrounding rock of the drifts caused by ventilation. The cooling-off of the surrounding rock is an ongoing process affecting the results of further geotechnical measurements in the near field of the drifts. To predict a realistic time and space dependent distribution of the temperature field of the host rock within the exploration area which is influenced by ventilation thermal model calculations are necessary. Comparing the calculated temperature field with the in-situ determined rock mass temperature field within the exploration area EB 1 the results show a sufficient agreement. Furthermore there is very good correspondence, both qualitatively and quantitatively, between the experimental and the calculated findings regarding the temperature profiles including the effects of excavation and ventilation of the drifts."

Jan 1, 2015

By Richard K. Komarek, Antonios Zavaliangos, Roman T. Dec

Current industrial compacting and briquetting practices are largely based on trial-and¬error techniques. This paper introduces a two dimensional finite element model of compacting/briquetting process in the roller press. Compared with other modeling techniques used in the past, finite element method offers the most versatile approach because it incorporates adequate information about powder behavior, geometry and frictional conditions and offers predictions for the density distribution, velocity field, stress distribution, roll force, roll torque and other important process variables. More over, when the model includes elasticity, it offers predictions on the internal stress state in the briquet after its exit from the pressing zone. This enables to perform realistic computer experiments which are helpful for establishing the pressing system design, forming cavity geometry and process conditions necessary to produce compacted or briquetted product with the desired properties.

Jan 1, 2004

By P. W. A Severin

"The Sturgeon Lake deposit, a partly eroded lens of massive sulphides with an underlying sulphide stringer zone, is one of five orebodies that occur in the Sturgeon Lake area of northwestern Ontario within volcaniclastic rocks of the Archean Wabigoon Subprovince in the Superior Province of the Canadian Shield.The Sturgeon Lake Cu-Zn-Pb-A g-Au deposit was discovered in October 1970 as a result of an I.P. survey. Production from this open-pit mine began in March 1974 and continued until the ore was exhausted in March 1980.The Sturgeon Lake property is underlain by basaltic volcanics, minor amounts of mafic lapilli tuff and rhyolite volcaniclastics. A quartz crystal-bearing rhyolite occurs at the top of the felsic volcaniclastics and is ""capped"" by the Sturgeon Lake massive sulphide deposit. The felsic volcanics have been intruded by a crudely layered sill-like, carbonatized mafic intrusion. Recent work suggests that the felsic rocks that underlie the Sturgeon Lake deposit are lateral equivalents of those in the vicinity of the Mattabi Mine and are not correlative with the dacitic volcaniclastics that underlie the Lyon Lake and Creek Zone deposits. Hydrothermal processes that resulted in the formation of the Sturgeon Lake orebody have resulted in a depletion of Na2O, CaO and FeO and an increase in MgO, K2O, copper and zinc. In the vicinity of the sulphide stringer zone, the rhyolites are ""bleached"" due to silicification and sericitization. The rocks lying immediately below the massive sulphides are locally strongly chloritic.The Sturgeon Lake deposit may have formed on a top ographic high which prevented mafic flows and dacitic volcaniclastics that underlie the Lyon Lake and Creek Zone deposits from inundating the Sturgeon Lake fumarolic vent from the west. Continued or resurgent activity from the Sturgeon Lake fumarole may have resulted in the formation of the Lyon Lake and Creek Zones as more ""distal "" deposits in topographic lows. The Sturgeon Lake, Lyon Lake and Creek Zone deposits were subsequently overlain by mafic tuffs and flows."

Jan 1, 1982

By E. Bonsall, J. J. Brummer, A. R. Graham

"A method and device are described for sampling diamond-drill core by cutting a continuous fillet of constant cross section from the cylindrical surface of the core throughout appropriate sample lengths. The apparatus employs a tapered, abrasive-set, cutting wheel, the conical cutting surface of which projects slightly into a rectangular core-guiding trough set parallel to the axis of rotation. The depth of fillet and thus the amount of sample per unit length can be regulated by adjusting the core guides. The freshly cut fillet itself, by engaging in a guide beyond the cutting wheel, acts to prevent rotation of the core during operation of the device.The cuttings which form the sample are normally collected in a tray below the cutting-wheel and appear at about 80 per cent -100 mesh. They require little or no further treatment or comminution before analysis. Speed, economy and convenience of sampling are thus greatly increased as compared with conventional sampling by im-1>act breaking or sawing, followed by crushing, grinding and sub division for assayAssays from fillets (about 1/20 the cross-sectional area of the core) and from 180-degree segments, from the same ninety-three core-samples, representing 431 feet of nickel-copper mineralization, gave the following results:"

Jan 1, 1968

By G. A. Pinsky, Pickard M. K

"IntroductionTWO METHODS of mucking have been used in sinking C shaft, the five-compartment production shaft of the Yellowknife property of Giant Yellowknife Gold Mines, Limited:(a) Band mucking during the original sinking in 1949 and 1950 (l); and(b) Mechanical mucking with the Cryderman shaft mucker during the recent deepening in 1954.This paper briefly describes the recent deepening and compares the performance figures of the two sinking operations.PlanningProduction planning in 1952 showed that it would be advisable to deepen C shaft in 1954 to provide for three new production levels and the installation of an underground crusher. To complete the required shaft work it would be necessary for a shaft crew to deepen the shaft about 500 feet, to partly excavate three level stations and a crusher station, and to cut a station for the loading pocket. Figure 1, a vertical section of the lower part of the shaft, shows the details of the deepening programme.During the planning period, Giant had a rather small supervisory staff and at the same time was experiencing a heavy labour turnover. As it was obvious that production would suffer if the sinking crew were recruited at the mine, it was decided that the merits of contracting-the shaft sinking to an independent contractor should be investigated."

Jan 1, 1955

By H. Sano

Most of the dust generated from the copper smelting process in Chile has been stored after the stabilization by hydrometallurgical process because it contains high concentrations of arsenic. However, in recent years, the dust generation has increased because of degrading the quality of concentrate. In addition, the environmental regulations become stricter. On the other hand, valuable metals such as copper and zinc are contained in the dust at high concentrations and it is desirable to recover them. In this study, the effect of dust recirculation to the smelting process was examined in order not only to decrease the amount of dust but also to recover copper. Dust generation and the distribution of arsenic, lead, zinc etc. among the matte, slag and gas phases were evaluated as a function of the amount of recirculated dust, partial pressure of oxygen and temperature. It was found that the direct dust return to the smelting process was quite effective for the recovery of copper and the reduction of dust generation, but the acceptable dust amount was limited by the produced matte quality.

Jan 1, 2007

By Chris Twigge-Molecey

Demand for metals will continue to grow as global population numbers and prosperity levels steadily increase. Consequently, there will continue to be a need to design and construct new metallurgical plants. Business success in general requires projects to be financially successful and return appropriate value to their owners. However, in the metals industry, private and public sector financing sources have become very sensitive to the perceived inability of projects to contain costs and meet other business objectives. Thus, the capital for projects has become more difficult and expensive to obtain. It is instructive to note that Ernst and Young (2011) identified that: “Delivery of predictable project results bestows competitive advantage and market confidence to those corporations who successfully instill this discipline”. The implication for future projects is that they must be systematically developed to minimize perceived risks—and more importantly—to demonstrate that the risks are managed to achieve the business case. Then, provided that the project has been developed in a well-structured way, project success can again be defined as a project with: a final cost within 10% of the budget approved at the end of FEL3, when the project is properly defined and the permit conditions are agreed upon; a start-up date within three months of the definitive, scheduled startup date; production levels at 85% of design capacity within a year of starting commercial operation; production meeting the target environmental restrictions; and with zero lost time accidents during construction and startup. The plant design is one of many integrated activities required to achieve these objectives. This book represents a valuable link between the existing engineering literature that encompasses a wide range of engineering fundamental textbooks and design manuals and the project management literature such as the Project Management Body of Knowledge, or PMBOK® (Project Management Institute, 2014). It is evident throughout this book, that the design team is a small but essential part of a much larger project team comprising the project management, construction management, and construction contractor staff. Design activities must be regarded and managed as part of the integrated whole, with two fundamental links throughout the design process:

Jan 1, 2015

By A. K. Verma

This paper provides a brief overview of evolution of deformations, stresses, and pore pressures due to different excavation stages during construction of an URL. Excavation of a rockmass develops a damage zone of finite width around the excavated zone which is associated with changes in permeability and which affects the fluid flow mechanism. In this study, a coupled hydromechanical (HM) analysis has been conducted for a water saturated porous rock mass which has been created by sequential excavation and backfill of vertical disposal pit of an URL. For this purpose, an Atomic Energy of Canada Limited?s in-floor concept for a deep geologic repository suitable for Indian conditions has been used. Changes in rock deformations, stresses, strains and mechanically induced pore pressure in an undrained condition, during excavation, as well as those caused by mechanically induced rock deformations after backfill of the disposal pit, have been modeled. A three-dimensional finite difference tool FLAC3D has been used for the analysis.

Jun 1, 2012

By A. W. Jacob

THE shatter cut, or burn cut as it is often called, is one in which the centre of the round is almost reamed out by drilling holes so close together that the blasting of a few holes shatters the rock embraced by all of them. The idea of shattering the centre of a face by shooting holes drilled parallel to one another is not new. Some miners have used this method for years past, when drilling quartz or a face near timber. But, they followed the age-old practice of first blasting the cut, then the square-up. It was not thought possible to shoot both together. In the case of machine men, the two largest contributors to silicosis are dust from drilling and dust from blasting. It follows, then, that material reduction of exposure to either constitutes an important step in lessening the incidence o silicosis. It was? the hope of being able to do away with the necessity of the men having to return early to a face, through dust concentrations of 60,000 to 80,000 particles per cubic centimeter, that aroused interest "in the shatter cut at McIntyre. Efforts to this end were successful. Now, with this kind of cut, all holes of a round are shot simultaneously.

Jan 1, 1942

"Here, we statistically proved that giant earthquakes occur at lunar phases specific to each subduction zone. Enough attention during the lunar period, especially when seismicity is occurring, will significantly reduce damage from giant earthquakes. Two case studies in which giant earthquakes occurred after seismicity in dangerous lunar phases were discussed, and the mechanisms underlying why giant earthquakes occur around neap tide at some subduction zones were explained by prohibition of giant earthquake occurrences due to high strain rates at spring tides at N–S subduction zones. The prohibition was statistically proven for uniaxial creep tests on Inada granite with slight stress disturbances. INTRODUCTIONIn previous studies, we showed that from 1900 to present, giant earthquakes (MW ??8) have occurred at lunar phases specific to each subduction zone (Fujii & Ozaki, 2012; Ozaki & Fujii, 2012). Although we later proposed a possible reason for these occurrences, the study lacked statistical analyses (Fujii et al., 2013). Therefore, this paper shows the results of such statistical testing and presents case studies for the Tohoku 2011 and Chile 2014 events, thereby providing updated data on giant earthquakes through July 2014."

Jan 1, 2015

By G. J. Arseneau

Mineral resource statements are reported as tonnage and grades. While great care is placed on generating a reliable estimation of grade, the determination of bulk density for resource estimation is often overlooked. Often mineral resource statements are prepared using a simple average value of bulk density. While a simple average estimate of bulk density can be appropriate for some deposit types, an over simplistic estimation of bulk density can result in serious errors in tonnage estimates and consequently to an over or under estimation of metal content. The construction of a reliable bulk density model requires an adequate bulk density database in order to develop a good understanding of the variability of bulk density with grade and geology. A reliable bulk density database is also essential in determining the appropriate modeling technique to minimize the errors in mineral resource statements caused by incorrect bulk density determinations. This paper summarizes bulk density measuring techniques and draws on examples from various deposit types examining the basic principles of bulk density modeling and domain construction for each deposit type. Examples are presented of simple bulk density domains and more complex grade variable bulk density domains with a discussion of best approaches for minimizing errors in density estimation.

Aug 1, 2013

By L. S. Almeida, U. A. Courbassier, C. T. Guimãaraes, M. N. Souza, V. L. Silva, H. P. Dias, G. A. Bicalho, B. S. Rocha, P. N. Rodrigues, A. Carnevale

During primary aluminum production the anode changing is a very important task. So improvements on it will be essential to avoid disturbance and have a better operational control. After anode changing a good current distribution will be guaranteed using a cavity cleaner and precise anode setting. Albras switching a manually anode setting to an automatic one solved the setting problems. In this paper it will be shown some pot line results and the improvements on workers ergonomic and safety conditions. The device was developed in a partnership between Albras and Pesto.

Jan 1, 2006

By A. Dahi Taleghani, Amir Shojaei

A continuum damage mechanics (CDM) based constitutive model has been developed to describe elastic, plastic and damage behavior of rock during drilling. In addition to inelastic deformations, this model incorporates rock anisotropies like toughness anisotropy due to the bedding planes orientation that is a common observation in soft Shales. The pressure sensitive inelastic deformation of porous rocks together with their damage mechanisms are studied for drained and undrained conditions. Fracture mechanics of microcrack and micro-void nucleation and their coalescence are incorporated into the formulation of the CDM models to accurately capture different rock failure modes. The performance of the developed elastoplastic and CDM models are compared with the available single cutter test data of a specific shale play and then the models are introduced into a commercial finite element package through user-defined subroutines. A workflow to derive the required model parameters is presented through inverse modelling of the single cutter test data. The developed CDM model outperforms the traditional discrete element and fracture mechanics approaches by removing stress singularities at the fracture tips and simulation of progressive fractures like formation of the cuttings ribbon without any essential need for remeshing. This model would provide a robust tool for modeling bit performance and rate of penetration using conventional elements of FEA with a reliable results and a computational cost less than similar computational techniques like discrete element methods.

Jan 1, 2015

By C. Peña, C. A. Zaror, M. Bustamante, M. Vega

The goal of this paper is to present the carbon footprint of Chilean cathodic copper, as a function of the electricity generation mix, ore grade, and process efficiency. Ore grades and acid leach-solvent extraction-electrowinning (LX-SX-EW) yields in the range 0.5-1.0% and 60-80%, respectively, were considered here. Additionally, electricity supply from two Chilean suppliers, SING (1.0 ton CO2/MWh) and SIC (0.4 ton CO2/MWh) was assessed. Simulation results show that oxide plants located in northern Chile, served by the SING network, feature carbon footprint within 4.3 - 11.4 MWh I ton cathodic copper, as compared with 3.5 - 9.3 MWh I ton copper in plants served by SIC. The footprint was found to increase as ore wade and process yields decrease.

Jan 1, 2011

By M. Dupuis, V. Bojarevics

It is well known that horizontal current density in the metal pad contributes greatly to the generation of MHD driven bath-metal interface wave. It is possible to compute very accurately the metal pad current density using a very detailed finite element model [1], but a MHD model must be compatible to this level of mesh refinement and to recalculate the current distribution at each time step, including the full busbar supply system. The accuracy of the instability prediction of the cell depends on the accuracy of the metal pad current density calculation. This study presents the comparison of the metal pad current density calculation of the detailed finite element model and the MHD-Valdis model for different metal pad heights and ledge thickness. It also presents the corresponding cell MHD stability predictions.

Jan 1, 2006

By A. Mortazavi, H. Nasab

"The storage of petroleum products on surface is associated with difficulties and limitations. Accordingly, a viable alternative is to excavate underground space in rock and provide a safe way for oil storage. Soft rocks such as salt domes provide good conditions from environmental and operational points of view. The potential for high-volume storage and low permeability are encouraging aspects for oil storage in salt domes. The complicated shape of oil storage caverns, the complicated behavior of salt rocks, and boundary conditions associated with large underground openings are important challenges in the design of oil storage caverns. The aim of this paper is to delve into the stability and deformation mechanisms of storage caverns created in salt domes. A parametric study of effect of the cavern size, orientation, and depth is carried out as a function of ground stress regime. The stress field and deformation mechanisms are calculated for each case aiming at providing design guideline.INTRODUCTIONOne of the most popular soft rock that is used for underground oil storage is salt rock (halite). Salt rock has particular characteristics which makes it suitable for oil storage. Salt rock has several advantages for oil storage, these are: high production rate, high degree of availability, short filling period, high level of safety and low permeability [1]. The low permeability is due to the fact that halite deforms in a plastic manner over a wide range of pressures, temperatures and rates of deformations. This property prevents joints or gaps opening up in the formation, thus preventing the escape of liquids and gases. The state of stresses around the cavern in salt domes depends on the depth of the cavern (initial stresses and rock mass temperatures are increasing with depth), the in-situ stress state within the rock mass, and the internal oil pressure in the cavern. Furthermore, the salt creep behavior and the cavern geometry are influencing stress redistributions during loading and unloading phases.Rock mass structure, cavern geometry, material behavior and cavern operation patterns require complex physical models to describe the load-bearing behavior of the geomechanical structure. The determination of stress, strain and deformation in the rock mass due to cavern construction and operation are complex problems which can be evaluated employing numerical tools such as the Finite Element Method (FEM) or Finite Difference Method (FDM). In this study, the finite difference method was used to evaluate the behavior of oil storage cavern in salt rock."

Jan 1, 2015

By Ralph W. Edie

"IntroductionTHIS PAPER presents some analyses of diabases from a number of metallogenic provinces in Canada and the United States. It is intended as a contribution to the literature on the genesis of mineral deposits associated with diabase.As it has been in the past, opinion today on the origin of the cobaltnickel- native silver and associated pitchblende type of deposit is sharply divided. Some geologists hold that this type of deposit is in some way genetically related to intrusive diabase; others are of the opinion that the deposits are related to granite. The controversy, like others of a similar nature, probably will not be settled satisfactorily for many years to come, •but in the meantime it is recognized that, with respect to most deposits of the type referred to, altogether too few facts are known for accurate conclusions on genesis to be drawn. To contribute in a small way to factual data on this whole .problem, the writer analyzed diabase from several districts in Canada in which deposits of the aforementioned type occur. For comparative purposes, the copper, cobalt, and nickel content of diabase from Cornwall, Pennsylvania, and of norite from the Sudbury basin of Ontario, was also determined.Insofar as is known, none of the analytical work undertaken had been previously carried out."

Jan 1, 1953

By James R. Hunter, Sandra K. Zacharias, Ursula M. Franklin

Archaeometallurgical remains can be a valuable source of information about past technological activities and, by inference, the societies that undertook them. Material traces of former metal-producing or metal-working centres can include raw materials, products, or metallurgical installations such as mines, furnaces or forges. Of these remains, the most common is slag, often left undisturbed since its original production. Physical and chemical analyses of archaeological slag and metal can often reveal the processes and materials involved in their formation. Mineral composition and softening temperature of a slag, for instance, can indicate the conditions of the metallurgical operation, such as temperature and atmosphere and, thus, help identify metallurgical processes which took place at a site(1). The present report illustrates the value of such analysis. Metal-working remains from Sainte-Marie among the Hurons, near Midland, Ontario, on the south side of Georgian Bay have been analyzed in order to determine the techniques and processes used by the 17th-century blacksmith who worked at the mission headquarters from 1642 to 1649. Samples were selected from a very large collection of blacksmith refuse which was excavated from the site by archaeologist Kenneth Kidd in 1941-42(2).

Jan 1, 1999