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"Acid resistant brick lined autoclaves and related vessels are utilized in pressure oxidation for the recovery of gold, copper, and other metals. The combination of the corrosion resistant membrane, acid resistant brick, mortar and steel shell is a composite system that requires a sophisticated stress analysis. In order to obtain meaningful results both the model and physical properties of the materials must be carefully selected. Evaluation of the calculated results requires an understanding of both the failure mechanisms of ceramics and experience with the performance of existing lining systems.INTRODUCTIONAcid brick lining systems are used in pressure oxidation autoclaves and related vessels to provide thermal and mechanical protection for corrosion resistant membranes that are applied directly to the interior of the vessel shell. The acid brick and mortar must be resistant to the process conditions and must provide a mechanically reliable structure.The construction of lined vessels incorporates a wide range of materials that can include the carbon steel vessel, austenitic weld overlay, lead lining, organic membrane, ceramic brick, mortars and other alloy components. The physical properties of the materials can vary by orders of magnitude and when combined in the construction of the lined vessel create a complex composite structure. The materials may be bonded together or act independently of each other. Stresses are induced into the lined vessel include pressure, thermal expansion, chemical expansion and mechanical loads.The complexity of these systems makes it is very difficult to account for all of the variables in the structural analysis of lined vessels. Historically calculations were simplified and designers primarily relied on experience with previous applications.The greatly improved tools for Finite Element Analysis (FEA) available today allow for detailed calculation of the stresses imposed on the vessel shell and lining. Koning & Lauzon (2004) presented a paper on design fundamentals including a discussion on the application of FEA methods at Pressure Hydrometallurgy 2004 in Banff. When a designer carefully constructs a model and selects the correct materials properties for the calculations, meaningful and useful results can be achieved."

Jan 1, 2012

By J. D. Bateman

Introduction The lifting of restrictions on the development of radioactive mineral deposits by private individuals has re-opened the search for uranium in Canada to a large body of professionally trained prospectors. The entry of private capital and experienced prospecting techniques into the search for radioactive minerals has been enormously stimulated by the atomic developments of the past several years; and we can now look forward to the discovery of new productive sources of uranium. The rate of new discoveries will, how ?ever, depend on the effectiveness of the methods used. The large number of new pitchblende occurrences reported within the past several months is largely a measure of the energy with which the portable Geiger-Müller counter has been applied in the field. The counter is simply a 'radio' receiver tuned to one of the products of spontaneous atomic disintegration that is characteristic of all radioactive materials. Its effective use depends largely on how it is applied under the various geological and topographical conditions that ma y be encountered, and also on an understanding of its limitations. Extensive geological information relating to the occurrence of radioactive minerals in Canada has been accumulated during the past several years, and it is now possible to define in a general way many of the geological formations in which pitchblende and related minerals are likely to occur. Furthermore, prospecting can be localized in those parts of the favourable formations that offer the greater promise of containing commercial deposits. In this selection, the Geiger counter is the most useful tool available to the prospector for the actual detection of radioactive materials. As an example, an area of two square miles in the Northwest Territories, within which about a dozen pitchblende occurrences had been found over a several year period by conventional prospecting methods, yielded more than forty-five additional discoveries by application of the Geiger counter. Yet earlier attempts at prospecting this area with the counter had failed, due largely to faulty instruments and lack of experience in field application. The limitations of the counter are very considerable; but, when they are recognized, there is no more useful tool for the discovery of radioactive ores. It was not until 1944 that a practicable portable counter was developed, and then only by co-operation in the field by geologists and physicists. Officers of the Geological Survey of Canada working with physicists of the National Research Council brought about the development of the modern counter.

Jan 1, 1949

By M. F. Goudge

Introduction It is only fitting on this occasion of the fiftieth anniversary of the incorporation of the Institute that we should indulge in a bit of retrospection and review the progress that has been made within this period in the various branches of the mining industry- progress that is so closely associated with the members of this Institute. Such a moment of retrospection will enable us better to appreciate the present status of the industry and to perceive more clearly the trends that should guide us in making sound plans for the future. The past half century has been a period of amazing industrial progress in Canada. In this period, the economy of our country has changed from one based chiefly on agriculture and the export of raw materials, to an economy based largely on a well integrated manufacturing industry. In all' o( these major developments, industrial minerals have played an important part and will play an increasingly, important part in the future. By ?industrial minerals? we mean the various non-metallic minerals (exclusive of fuels) as well as the rocks, sands, and clays used for industrial purposes. They are now used so widely and in such large quantities that modern industry could not function without them, and their continued availability at low cost is vital to the industrial future of Canada. The key position occupied by industrial minerals in modern Canadian industry was well illustrated two years ago when a strike occurred in the only Canadian plant producing soda-ash and calcium chloride at a time when those materials were already in short supply and unavailable from other sources. Within a short time of the shutdown of this plant, in which the two principal raw materials are limestone and salt, the great aluminium reduction plants on the Saguenay river were forced to curtail operations because of the lack of soda-ash, essential to the process of extracting aluminium from its ore. Automobile production, already harassed by a shortage of steel, was further hampered when glass for windshields and windows could not be supplied because the glass industry was slowed down almost to a standstill for want of soda-ash. Soap became almost unobtainable both to the housewife and to industrial users, because soda-ash is required in its manufacture. As a consequence of the soap shortage, the production o synthetic rubber at Sarnia was threatened because soap in large quantities is essential to the polymerization process. Motorists on gravelled highways all over Eastern Canada drove through clouds of dust because calcium chloride, used for dust laying, was not to be had. There were other cases of dislocation of industry related to the shutdown of this particular plant, but the above illustrates the wide ramifications of industrial minerals in modern industry. However, it is extremely doubtful if many Canadian citizens realized that these apparently unrelated happenings were connected in any way with limestone and salt.

Jan 1, 1948

By A. Roy MacLean

"In the Maritimes, there are twelve coal areas. From east to west, these include the Sydney coal field, the St. Rose - Chimney Corner, Inverness, Mabou, Port Hood, Pictou, Colchester - Debert, Springhill, Joggins - Chignecto, Beersville, Lake Stream, and Minto. The first eight are in Nova Scotia while the remaining four are in New Brunswick.In all these areas, the coal was formed during the Carboniferous period, which existed some 300 million years ago. However, within this period not all coal formation took place during the same time. There were three main intervals, which occurred at the time that the Riversdale, Cumberland and Pictou groups were laid down (Hacquebard, 1970). The oldest coals are those of the Riversdale Group. These coals were of rather limited extent, and only a few mineable seams are present, particularly at St. Rose -Chimney Corner and Port Hood. From these two areas only 2 M tons have been extracted, and 'measured' resources of 7 and 9 M tons respectively remain. The Cumberland Group coals are confined to Cumberland County and include the coals of Springhill and Joggins River Herbert -Chignecto. Some 43 M tons have been removed and only 7 M tons of 'measured' coal remain, with an addit10nal 39 M tons of 'inferred' resources. However, there are additional resources at Springhill, which will be discussed in more detail in a later section. The coals of the Pictou Group are the youngest and the most abundant, both in actual number of seams and in regional distnbution. These coals were formed during the Westphalian C and D, a time during which the main coal deposition in Europe also took place. Here belong the coals of the Sydney, Inverness, Mabou, Pictou, Debert, Beersville, Lake Stream and Minto fields. Their total production amounted to 469 M tons or 91 % of the Maritime total of 514 M tons. The remaining resources of all Pictou Group coals have been calculated at 254 M tons of 'measured' coal and 949 M tons of 'inferred' coal. As can readily be seen, the bulk of both past production and remaining resources occur in the Sydney coal field. The Sydney figures represent 73% of total production, and 87% of total 'demonstrated' resources in the Maritime Provinces. Next to Sydney, the Pictou coal field has been the greatest producer, with 59 M tons; it also has the second largest 'measured' resources, amounting to 25 M tons. However in terms of 'inferred' coal resources, the Mabou coal field, ~ith 140 M tons, ranks second to Sydney."

Jan 1, 1985

By D. B. Smith

DURING the summer of 1953, test work commenced at the Sullivan Concentrator with a view to the modification of filtration practice by the inclusion of wet cyclone classification of the lead concentrates, with separate filtration of the underflow and overflow products. Formerly, practice was conventional and the equipment employed comprised one 50-foot diameter thickener ?with the underflow routed via a 20-foot stock tank to two 8-foot by 12-foot Oliver filters. Heating of the filter feeds to 40° C. and the use of mechanical slappers on the filter drums ?have both been standard features of Sullivan practice for years. Both of these have been retained. Currently (February, 1956), lead concentrates are being classified into sands and slimes by 12-inch cyclones with the underflow, at 75 per cent solids, being fed to No. 1 Oliver filter. The overflow is thickened to 75 per cent solids and filtered separately by a No. 2 Oliver filter . The tonnage split is approximately two of underflow to one of overflow. The overflow contains 75 to 80 per cent of the total minus I 500 mesh slimes in the feed.

Jan 1, 1956

By H. W. Manley

SULPHUR, like the minerals of coal, iron and petroleum, is one of the essential materials in our modern expanding industrial civilization. Before discussing the salient features of the production of sulphur from the Canadian sour gas, it seems appropriate to outline the historical past and probable future utilization of sulphur. The ancient Greek writer Homer spoke of its "pest-averting sulphur" and the "divine purifying fumigation". Ancient alchemists found sulphur to be a fascinating and baffling material. The discovery of gun powder in the year of 1250, and its application to the art of war a, century later, made sulphur an important commodity in the progress of mankind. The initial manufacture of sulphuric acid in the year of 1736 by the Englishman Joshua Ward, established the basis of a chemical industry that today utilizes 80 per cent of the consumption of elemental sulphur. Commercial production of the chemical soda ash ( N a2C03) discovered in 1787 by the famous Leblanc Process, in-creased international demand for the element sulphur and marks the birthday of the Sicilian sulphur industry.

Jan 1, 1961

By Mitchell P. Rothman

This paper concentrates on profits and other measures of return in the Canadian mining industry, especially in the non-mineral-fuels sector. The paper examines the historical patterns of mining profits, both before and after taxes, as compared with profits in other sectors of the Canadian economy, as well as some of the more important influences on mining profits. These include the prices of mineral products, provincial and federal tax policies with respect to mining , and the effect of inflation on mining profits and the financial position of mining firms - in each case, comparing mining with the other sectors of the economy. Finally, the paper provides an analysis of current and prospective rates of mining profits in relation to the capital required to ensure the future viability of the Canadian mining industry.

Jan 1, 1977

By L. Paulino, R. A. Camilli, J. Yamamoto, J. C. Araujo

The first paper presented on this work [1], showed how bath ratio was increased from 78% to over 95% using a structured approach to reduce bath chemistry variability. This update will illustrate the steps taken and update the results presented earlier, showing the effects of long power interruptions and several load reductions as well as load increase during the period from 1999 to 2005. Current efficiency was affected by such processes upset; however, bath ratio in range (±0.05) is still higher than 90%, even after an increment of more than 6 kA. This review will explain each of the steps taken to reach stability in this critical smelting parameter.

Jan 1, 2006

By L. E. Djingheuzian

ANON-CATARACTING (N-C) ball mill is so operated that the balls are not thrown in-ward at the top of their paths. The result is to maintain, in the mill, a quiescent pool in which classification will occur at a limiting size corresponding to the pulp density. N-C operation is produced by effecting proper relationship among mill speed, ball diameter, volume of ball load, and pulp density. Such operation is typified by the primary ball-mill operation of the Tennessee Copper Company, Copper-hill, Tenn., and the Cleveland Cliff Iron Company, near Ishpeming, Mich.

Jan 1, 1958

By R. E. Baylis, M. R. Tolley, S. Singh, A. J. Murray, R. Boden, L. E. Macaskie, T. P. Hathway, D. Vavlekas

We report rare earth element (REE) recovery using immobilized Serratia biofilm depositing metal phosphate via a robust enzymatic mechanism. Activity was approximately halved at pH 3.5 and restored at pH 5.5. REE(III) was recovered selectively against Th(IV) but the method was non-selective between different REEs (La, Y, Eu, Nd). Biofilms were active for a year (half life of ~ 3 months). The activity of aged biofilm was enhanced by pre-nucleation (‘priming’) with NdPO4 prior to onset of flow-through conditions. The use of different ‘priming’ metals and bacteria via a combinatorial approach revealed some REE selectivity through the selective exclusion of specific REEs.

Jan 1, 2014

By S. Esfahani, M. Barati

Heat recovery from blast furnace slags is often contradicted by another requirement, to generate amorphous slag for its use in cement production. As both the rate and extent of heat recovery and slag structure are determined by its cooling rate, a relation between the crystallization kinetics and the cooling conditions is highly desired. In this study, slags with different basicities were studied during non-isothermal cooling. Their continuous cooling transformation (CCT) diagram were plotted and compared with each other. Then, a mathematical model was developed that predicts the amount of crystallization during cooling. The results were validated by experiments performed by Single Hot Thermocouple Technique and image analysis. A second mathematical model that calculates temperature history of slag during its cooling was coupled with the above model, to allow optimizing the slag/air ratio for both heat recovery and slag glass content.

Jan 1, 2015

By Christiaan Zeilstra, Jan van der Stel, Koen Meijer, Gerard Louwerse, Tim Peeters

The steel industry is producing about 5% of the world wide CO2 emission. Therefore the European steel industry has defined a research program to reduce the CO2 emission by 50% per ton: ULCOS. Since its start in 2004 ULCOS has identified four technologies for further development. Two of these technologies which produce liquid hot metal are discussed. The ULCOS blast furnace is based on recycling of decarbonated topgas and the capture and storage of CO2. The concept has been demonstrated during three campaigns at LKAB EBF in Luleå, Sweden. The smelting reduction process HIsarna is a combination of the cyclone-technology and Hismelt. The process has been demonstrated successfully in four campaigns at a pilot installation on the IJmuiden steelmaking site.

Jan 1, 2015

By A. O. Dufresne

WITHOUT transportation, mining would be quite impossible. Any person familiar with the operation of a mine knows full well that from the minute ore is blasted, it is kept moving until it reaches the treatment plant. In the mill, by means of conveyors and elevators, the ore is brought from receiving bins to one machine after another until finally its valuable mineral is separated from the gangue. The finished product must then be shipped -either by boat, rail, or motor trucks to industrial centres, where it undergoes further treatment and transformation into finished commercial goods. Everybody appreciates that the winning of an or-e includes, amongst various operations, the moving of large quantities of material of generally low value. Transportation, therefore, must be considered One of the most important factors in the economics of mining. My assignment, this afternoon, is not to treat of that phase of transportation as it directly affects mining operations, but rather to consider some of the aspects of overland transportation and its influence in bringing about the development of mining camps in Canada. I shall take the liberty of rapidly surveying conditions facing prospectors, mine developers and operators from the time a region is still in a pre-pioneering stage until such time as a mine starts shipping its concentrates.

Jan 1, 1956

By U. Erb, L. Monaco

"Electrodeposited nanomaterials are increasingly implemented in advanced industrial applications in the aerospace, automotive, defence, electronic and energy sectors due to their outstanding physical, chemical and mechanical properties, including increased strength and wear resistance, and superb magnetic properties. As with the development of any class of new materials, the corrosion behaviour of these electrodeposits requires considerable attention. This presentation reviews major developments in the understanding of the corrosion behaviour of nanocrystalline metals, alloys and metal-matrix composites over the last 20 years, with emphasis on how their intrinsically high density of intercrystalline defects does not compromise their corrosion resistance as initially expected.INTRODUCTIONOver the past 20 years there have been considerable advances in the understanding of the corrosion behaviour of nanocrystalline metals, alloys and metal-matrix composites. In this paper, the corrosion properties of nanocrystalline nickel, cobalt, zinc, and copper and some of their alloys are reviewed with emphasis on how a reduction in grain size affects their corrosion behaviour in different environments.It is possible to synthesize nanocrystalline material with microstructural refinement down to the range of 1 to 100 nm using a large number of processing methods. There are five basic synthesis methods that can be used to classify the different techniques: vapor-phase processing, liquid-phase processing, solid-phase processing, chemical synthesis, and electrochemical synthesis. Depending on the synthesis method, different microstructures (equiaxed, textured), shapes, and forms (films, particles, bulk material) may be produced. In addition, other factors may be introduced (eg. residual porosity or amorphous phases), aside from microstructural refinement, which can contribute to the observed properties (Erb, 2010). In order to interpret and categorize the resulting microstructures, a dimensional structure modulation scheme was introduced by Siegel (1996) in which zero-dimensional nanomaterials refer to individual particles, clusters, etc. One-dimensionality results from a layered (less than 100 nm thick) structure. Two-dimensional nanomaterials are thin, layered structures containing grains (less than 100 nm) within each layer. Finally, three-dimensional nanomaterials are bulk structures with an average grain size less than 100 nm."

Jan 1, 2012

By David G. Dixon, Ahmad Ghahremaninezhad, Edouard Asselin

"Atmospheric leaching of chalcopyrite in sulfuric acid solutions is a slow process due to the mineral’s passivation. We have investigated the nature of the passive film in this work. Electrochemical reduction and oxidation of chalcopyrite over the potential range of -0.5 to 1.2 VSHE were investigated in 0.5 M sulfuric acid solution (pH 0.3) at 25 ºC by multicyclic voltammetry and open circuit potential measurement. The influence of scan limits on the evolution of current peaks was studied with both stationary and rotating electrodes. It was observed that the anodic oxidation of chalcopyrite begins at potentials above 0.6 VSHE, most likely by preferential dissolution of iron atoms over copper atoms. The selective electro-dissolution process results in formation of a metal-deficient sulfide passive film (i.e. Cu1- xFe1-yS2, y > x). The passive film dissolves at 0.9 VSHE. Elemental sulfur is one of the products of chalcopyrite dissolution above 1.0 VSHE. Cathodic reactions within the potential region of 0.1 to 0.6 VSHE and anodic reactions at potentials lower that 0.5 VSHE are associated with at least one soluble species from solution. The soluble species involved in the cathodic reactions are likely ferric and cupric, while the soluble species involved in the anodic reactions is likely H2Saq."

Jan 1, 2014

By P. A. Gonzalez Contreras

Scorodite is considered as a secondary mineral formed from the product of weathering of primary minerals by chemical or biological reactions. In the case of biological scorodite formation, microorganisms mimic and accelerate what in nature takes a very long time, i.e. biocrystallisation. The goal of the biological scorodite formation is to form very stable arsenic crystals suitable for long-term and safe disposal. The biological formation of scorodite is a novel combination of biological oxidation, biocrystallisation, and proper bioreactor design to achieve the biological formation of scorodite crystals in one step. We have explored simultaneous biological arsenic and iron oxidation at 30ºC and at 70ºC leading to arsenic-jarosite phases and scorodite, respectively. As biologically formed scorodite crystals are very stable (TCLP < 1 mg/L As (V)), the risk of arsenic toxicity is minimized when leaching takes place. This process is suitable for arsenic concentrations above 0.5 g/l As achieving up to 20 mg/l As in the effluent. This biological scorodite formation system is a selfsufficient bio-oxidation system and therefore many new applications can be explored such as reprocessing of arsenic trioxide, orpiment or calcium arsenate to scorodite crystals for a stable and safe disposal.

Jan 1, 2014

By D. K. Fountain

"High metal prices and advanced technology in open-pit mining methods have resulted in considerable interest in the development of large, low-grade mineral deposits. Brenda Mines Limited is presently testing such a deposit of copper-molybdenum mineralization near Penticton, British Columbia.The mineralization of economic interest at Brenda has a total metallic sulphide content of between 1 and 1.5 per cent. This sulphide content approaches the limits of detectability of standard geophysical methods. How-ever, due to a favourable geological environment, it has been possible to utilize the Induced Polarization Method to outline the mineralization at the Brenda property."

Jan 1, 1968

By R. K. Mishra, A. Kula, X. Jia, M. Niewczas

The mechanical properties of Mg-Gd and Mg-Y solid solutions have been studied under uniaxial tension and compression between 4K and 298K. The results reveal that Mg-Gd alloys exhibit higher strength and ductility under tension and compression attributed to the more effective solid solution strengthening effect and grain boundary strengthening. Profuse twinning has been observed under compression, resulting in a material texture with strong dominance of basal component parallel to compression axis. Under tension, twining is less active and the texture evolution is affected mostly by slip. The alloys exhibit pronounced yield stress asymmetry and significantly different work-hardening behaviour under tension and compression. Increasing of Gd and/or Y concentration leads to the reduction of the tension-compression asymmetry due to the weakening of the recrystallization texture and more balanced twinning and slip activity during plastic deformation. The results suggest that under compression of Mg-Y alloys slip is more active than twinning in comparison to Mg-Gd alloys.

Jan 1, 2015

The Carboniferous sedimentary rocks of southwestern Newfoundland merit investigation because of petroleum, salt and gypsum possibilities and indications of base metallization along the equivalent of the Horton-Windsor con-tact. In this paper, Lower Mississippian (Anguille) strata are divided into three formations: (1) the Cape John below, (2) the Snakes Bight and (3) the Seacliffs. A correlation between these formations and the Craignish, Strathlorne and Ainslie formations of the Horton group? in western Cape Breton Island is suggested. The criteria for the Anguille subdivision are essentially lithological, but preliminary study of included spore assemblages suggests more precise interformational correlations between Anguille and Horton sequences. The re-measured lower portion of the type section of the Codroy group is presented to define more clearly the stratigraphic position of numerous gypsum and limestone beds. Because of rapid facies changes within the Codroy group a simplified two-fold division into upper and lower units is proposed on the grounds of

Jan 1, 1964

By B. J. Keating

"AT PRESENT, it is not certain that any of the sulphide de in the Province of Nova Scotia attain the lower grade limit of 60 per cent sulphides over the minimum area of 1,000 square feet suggested as cut-off specifications for inclusion in this Symposium. However, several of them do include massive sections of substantial size and others represent concentrations of sulphide material that are well above average. It is felt, therefore, that a tentative classification of the deposits and presentation of their geological settings are justified and may help round out the genetic aspects of this study. Accordingly, data considered to be the most pertinent are assembled here in the event that some may fit into larger-scale patterns of mineralization that may take shape as a result of this investigation.The three principal massive sulphide deposits in Nova Scotia are the Stirling, the Smithfield, and the Walton. The locations of these are shown on the accompanying key-map (Figure 1).Three other deposits, the locations of which are also indicated on the map, are the Meat Cove, Rocky Brook, and Gays River de¬posits. Although these fall far short of the minimum dimensions and grade specifications referred to above they are singled out because they have received more than passing attention and are illustrative of the mineralization types to which they belong."

Jan 1, 1960