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By T. T. Chen

Hydrometallurgical products are difficult to characterize because of their fine grain sizes, heterogeneity, often amorphous structures and water soluble or hydrated constituents. Such products are advantageously studied using complementary mineralogical techniques including >50, ore microscopy, SEM-EDX, electron microprobe analysis, selective leaching and wet chemical analysis to determine the phases and their morphologies, to identify specific element carriers, and to elucidate the chemical reactions occurring during the metallurgical process. Sample preparation is an important consideration for these materials. For extremely fine-grained particles, or soft and brittle products such as elemental sulphur, the study of loose powder mounts provides information not available from the examination of polished sections. To demonstrate the application of the various mineralogical techniques, commercial zinc roaster calcines and leach residues, copper refinery anodes and anode slimes, and laboratory bornite leach residues were examined in detail. The various sample preparation and mineralogical methods are presented, and the use of these complementary and practical mineralogical techniques to improve the understanding of a particular hydrometallurgical system is discussed.

Jan 1, 1989

By James D. Hall

THIS essay deals with the materials and methods used in the waste filling of scopes in Canadian mines, with especial reference co the methods used at the Sullivan mine, Kimberley, B.C. The author would like to thank members of the staff of the Sullivan mine for information obtained, and acknowledges material from the following publications: Waste Filling of Stopes: Information Circular 6816, U.S. Bureau of Mines. Mining Methods and Practices at Lake Shore, by Leslie S. Weldon; Trans., C.I.M. & M., Vol. XXXIX, 1936, pp. 142-202. Development and Mining (at the Mcintyre Mine), by D. E. Keeley; Eng. & Min. Journal, November, 1933. INTRODUCTION Although mining in Canada is a relatively youthful industry, many of our mines have reached a stage of extraction which requires waste filling, both as a means of support and co make possible the winning of ore that would otherwise have co be left in the mine. Fill may be used at regular intervals as one of the cycle of operations, as in cur-and-fill and square-set scoping; or it may be introduced into a completed stope co provide permanent support for overlying rock formations, and co permit mining of pillars of valuable ore. Waste fill is sorted in resuing, which is a form of cut-and-fill scoping employed in narrow veins.

Jan 1, 1937

By Henrique Dias Gatti Turrer, Marcelo Nazaro Silva, Henrique Lopes Martins Pereira, Claudio Luis Goulart

The Minas-Rio industrial complex uses a pipeline with extension of 529 Km to transport the iron ore concentrate to the filtering industrial complex and exporting port. Since project phase, bench lab tests have provided important information for the pumped slurry rheology control. Based in these tests results was possible to verify the effects of slurry stability, rheology controller type and particle size distribution in the regrinded concentrate yield stress and relative viscosity. Controlling some characteristics of pumped slurry, such as particle size distribution, pH and solids concentration guaranteed to achieve the necessary rheology properties for its safe pumping through pipeline and resulted in a performance improvement over the years.

Oct 3, 2019

By E. J. Wade

The general location, climatic conditions and access of the Tasu mine are covered briefly, with comments on the Jack of conventional transportation and communication facilities. The Haïda story of Tasu and early at-tempts at production are presented, together with a discussion of the government legislation which throttled exploration and production in the late fifties. General and specific details of local geology, mineralogy and current ore reserves are also covered.

Jan 1, 1968

By Frank Speller

WE are here to honor again the memory of Henry Marion Howe, one of the foremost metallurgists of his time, and it is indeed a great privilege to be called upon by the Board of Directors of .this Institute to give the memorial address this year. Professor Howe started active investigation of corrosion of iron from a metallurgical standpoint in 1887, and made several important contribu-tions to the subject from 1895 to 1908.(1) ? The papers named in the bibliography are only a few of his valuable papers, but in all his works he sets a high standard of scientific accuracy, together with a clearness and power of expression rarely equaled in engineering literature. There-fore it seems appropriate on this occasion to review the work on corrosion of this distinguished gentleman and then endeavor to make a brief inventory of what has been accomplished since his time. Howe saw the beginning of the steel industry in America and before he died (May 14, 1922) witnessed it develop to a production of 45,000,000 tons per year. He was naturally very much interested in the infant industry and was quick to see the importance of the question of corrosion. It was my privilege to discuss the subject of corrosion frequently with Professor Howe at various times from 1905 to 1908; in this, as in other metallurgical problems, he sought the truth without bias and always insisted on proving an opinion or conclusion before accepting it. We should remember that when Howe started his investigation of corrosion, in 1887, steel was rapidly supplanting wrought iron. Certain papers in the early eighties (now forgotten) claiming much greater durability for wrought iron than for steel aroused Howe's interest. He could not reconcile the statement that steel was intrinsically and incurably less durable than wrought iron with the continued and widening use of steel,

Jan 1, 1934

By E. J. Rapperport, M. F. Smith

A presentation of the W-Ru constitution diagram is given. Techniques utilized in the determination of phase boundary values include electron micro-probe analysis of two-phased alloys and diffusion couples, as well as normal metallographic and X-ray methods. The primary features of the diagram are: 1) a terminal solid solution of ruthenium in tungsten with a maximum solubility of 23 at. pct Ru at 2300°C; 2) a terminal solid solution of tungsten in ruthenium with a maximum solubility of 48 at. pct W at 2205°C; 3) a o phase of maximum breadth about 6 at. pct based on the composition W3Ru2 which forms peritectically from the melt at 2300°C, and which decomposes eutectoidally at 1667 °C to form a twigs ten and 0 ruthenium; 4) a eutectic at 45 at. pct Ru and 2205°C with the products being o plus ß ruthenium. THE W-Ru diagram has previously been studied only in a cursory fashion. Raub and alter' obtained a 1400°C isotherm in which they observed no intermediate phases, and on which they established the limits of solubility as 36.5 at. pct W in ruthenium and about 1.5 at. pct Ru in tungsten. In addition, Obrowski2 found a o phase forming peritectically from the melt and existing only above 1650°C. Below this temperature the phase was presumed to decompose eutectoidally. The present work finds the diagram as given in Fig. 1. I) EXPERIMENTAL PROCEDURE The materials used for alloy preparation in determining the W-Ru constitution diagram were 99.9 pct pure ruthenium powder supplied by Baker Chemical Co., and 99.9 pct pure tungsten powder from General Electric Co. Typical analyses of these elements are given in Table I. Initial alloys at 10 at. pct intervals were prepared from the metal powders by the following method. Powders sufficient for 25 g of the alloys were weighed out with an accuracy of 0.1 mg and blended mechanically. After blending, the powders were compacted, in a steel die, at approximately 30,000 psi. The compacts were sintered in an electric vacuum furnace in order to remove adsorbed gases and to achieve partial densification prior to arc-melting. Vacua of 10-4 mm Hg or less were maintained in sintering as the furnace temperature was raised to approximately 2000°C. Sintering times ranged from 10 to 20 hr. The sintered compacts were arc-melted under a protective atmosphere of purified helium. Melting was conducted on a water-cooled copper hearth, utilizing a nonconsumable tungsten electrode. In the melting process, each alloy was turned over and re-melted on opposite sides from four to six times to ensure complete melting and to eliminate gross in-homogeneities. The arc-melter used had a vacuum capability of 5 X 10-6 mm Hg, and a leak rate of about 20 -liters per hr. Chemical analysis techniques for refractory metal-platinum group metal combinations are not well-established; therefore, composition control and determination depended principally upon weight-loss observations and calculations. This consisted in weighing each alloy after sintering and after arc-melting, and calculating the maximum and minimum composition values, assuming the total weight losses to be first all tungsten, and then all ruthenium. Since composition uncertainty was directly related to weight loss, care was taken to minimize losses in handling, compacting, and melting. Prior to homogenization and equilibration the as-arc-melted alloys were analyzed in several

Jan 1, 1964

By R. A. Wyman, F. E. Hanes

THE demand for high-quality aggregate is increasing in all phases of the construction industry and in all organizations associated with road building in Canada. The production of aggregate in Canada has increased almost continuously since the end of the war and has quadrupled since 1948. Increases during the past fifteen years can be accounted for by the expansion in all types of construction, particularly that of roads and highways. Total construction in 1959, based on preliminary estimates, has been valued at $7 billion, and an increase fore-cast for 1960 indicates optimism on the •construction horizon (1). Cement produced in Canada in 1959 amounted to 6.3 million tons. This is more than 2.5 times the 1948 production. Increased cement production indicates an increased use of concrete, and thus an increased need for aggregate. Natural sand and gravel deposits are gradually being depleted.

Jan 1, 1962

By Gordon R. Peeling

The Problem Five years after the consensus of the Whitehorse Mining Initiative the industry was losing public confidence Public opinion surveys ranked mining just above the tobacco industry Project opportunities were being lost to public and political opposition Operating practices called into question by a number of tailings dam failures CBC broadcast of "The Ugly Canadian" Our social licence was being lost

May 1, 2013

By Eamonn F. Maher

Superconductivity is one of the most remarkable scientific phenomena ever investigated. It is the phenomenon whereby some materials exhibit zero resistance to the passage of an electric current when cooled to low temperatures, and requires a quantum mechanical explanation. Four Nobel prizes in physics have been awarded specifically on the subject of superconductivity, with many more enabled by superconducting technology. For example, particle beams are generated in accelerators and manipulated in ?particle beam lines? in the ?Big Physics? projects around the world eg. at CERN, Geneva, leading to major discoveries in fundamental particle physics. Similarly, at the JET Propulsion laboratory near Oxford, U.K, controlled nuclear fusion has been demonstrated, and magnetic containment of plasmas is key. In the chemical and biological sciences high field NMR spectroscopy has become indispensable for examining organic matter, revealing the mysteries of the workings of cells, genetics, and in the development of new polymers and pharmaceuticals. With all these very advanced uses for superconducting magnets, it is easy to forget that superconductivity is big business, not just a scientific curiosity. MRI (Magnetic Resonance Imaging) superconducting magnets, the key component of high resolution body scanners, use approximately half of the world?s superconducting wire ? the other half being mostly used in accelerator magnets. The MRI market is about 3 billion dollars per annum, and one MRI magnet uses 200km of wire. New applications for superconducting magnets are now appearing including ?Catheter steering?, enabling much shorter timescales for life-saving brain tumour removals and ?Functional MRI?, a whole new area in patient diagnostics. Whilst the use of low temperature superconductors (LTS) is now well established commercially in superconducting magnets and niche electronic applications, the application of LTS in electric power distribution and transport has been very limited to date. It is now more than fifteen years since the so-called High Temperature Superconductor (HTS) materials were discovered: these can be operated at liquid nitrogen temperatures rather than liquid helium temperatures. However, materials processing and scale-up issues have prevented their widespread use, and in particular the required price/performance criteria are only beginning to be reached except in certain niche markets. BSCCO (Bismuth Strontium Calcium Copper Oxide) tapes up to one km long are now readily available, and have been demonstrated in high current cables for power distribution networks, but the general consensus is that 1) it is difficult to reduce the price much further because of the silver matrix required and 2) in applications where coils are required eg. motors, generators, transformers etc the properties of BSCCO are rather poor because of the critical current dependence on magnetic field. Magnetic fields are always associated with coils and windings, and such fields are of course fundamental to the operation of all electrical machines. YBCO (Yttrium Barium Copper Oxide) however, has good characteristics in field and for the last few years there has been intensive research and development costing several tens of millions of dollars worldwide into the scale-up of production of so-called ?coated conductor?. This ?second generation? tape can be produced by any of many different film deposition techniques, with more or less success for short lengths, but as yet it is unavailable in lengths more than a few tens of metres.

Oct 1, 2003

By T. S. Blair

I feel a certain sense of responsibility in bringing before you the subject of the direct process in iron manufacture. I am aware that, in such a body as I have now the honor of addressing, there are few who are not already so well informed upon its past history that it would be a weariness to them to listen to anything else than an account of practical success. Yet, to claim that success involves so much that, if I do not make good my claim, I deservedly expose myself to severe criticism. The whole literature of the art, so far as it relates to the direct process, is, up to this time, but a history of failure. It is safe to say that more money, time, and talent have been fruitlessly spent in the pursuit of this object than in all the other unsuccessful efforts in the whole line of iron metallurgy. A distinguished authority in patent law has remarked that " the invention records of the United States and of foreign countries are filled with the waifs and abandoned relics of these abortive struggles." Dr. Percy, whose great work may be taken as an epitome of all that was worth mention, whether useful or curious, in pig-iron metallurgy, up to the date of its publication (1864), after giving elaborate accounts of various attempts at the direct process, condenses his own opinion of all that had been then effected, into a brief but summary comment upon a pamphlet of one of the sanguine inventors who had said: "It is evident that the present mode of working iron

By Edgar C. Bain

In studying the structural characteristics of martensite it is desirable that a clear conception of the material from which martensite is produced should first be obtained. Any theory of its formation and structure incompatible with the facts of its parent substance, austenite, can be eliminated with little consideration. Austenite is the name applied to solid solutions of carbon and other elements in gamma iron. At temperatures above about 900" C. (1650" F.), pure iron exists in a system of crystallinity1 entirely different from the crystal structure below that temperature. This high-temperature allotrope of iron is of an atomic structure associated with great ductility, having very manifold symmetry and an abundance of easy slip planes. The exceptionally ductile and malleable metals (gold, silver, platinum, copper, aluminum, and nickel) have this same atomic arrangement— the face-centered cubic. The low-temperature allotrope of iron, alpha iron, the solid solutions of which are known as ferrite, has a body-centered cubic arrangement of atoms. Like it, in crystal structure, are the less ductile and malleable metals, molybdenum, tungsten, titanium and chromium. Fig. 1 shows the two atomic arrangements known in iron; the diagrams are drawn to scale. Either of these modifications of iron may dissolve other elements in the solid state; by so doing, the temperature of the transformation is changed. In general 2-7, it appears that a solid solvent metal dissolves a metal solute by substituting foreign atoms in its own space lattice. Thus, iron may dissolve nickel in either of its crystalline forms by permitting an atom of nickel here and there to occupy the normal position

Jan 1, 1924

By Shail J. Butani

In 1986, the Bureau of Mines conducted a probability sample survey, Mining Industry Population Survey, to measure such employee characteristics as occupation; principal equipment operated; work location at the mine; present job, present company, and total mining experience; job-related training during the last 2 yr; age; sex; race; and education. The population estimates are necessary to properly analyze the Mine Safety and Health Administration (MSHA) injury (includes illness and fatality data) statistics; that is, to compare and contrast injury rates for various subpopulations in order to identify those groups that are exhibiting higher than average injury rates. This report uses the survey's results to characterize the U.S. coal mining workforce from March through September 1986. A companion report, Information Circular (IC) 9193, "Characterization of the 1935 Metal and Nonmetal Mining Workforce:' provides similar information for the U.S metal and nonmetal mining industry.

Jan 1, 1988

By Edgar C. Bain

In studying the structural characteristics of martensite it is desirable that a clear conception of the material from which martensite is produced should first be obtained. Any theory of its formation and structure incompatible with the facts of its parent substance, austenite, can be eliminated with little consideration. Austenite is the name applied to solid solutions of carbon and other elements in gamma iron. At temperatures above about 900" C. (1650" F.), pure iron exists in a system of crystallinity1 entirely different from the crystal structure below that temperature. This high-temperature allotrope of iron is of an atomic structure associated with great ductility, having very manifold symmetry and an abundance of easy slip planes. The exceptionally ductile and malleable metals (gold, silver, platinum, copper, aluminum, and nickel) have this same atomic arrangement— the face-centered cubic. The low-temperature allotrope of iron, alpha iron, the solid solutions of which are known as ferrite, has a body-centered cubic arrangement of atoms. Like it, in crystal structure, are the less ductile and malleable metals, molybdenum, tungsten, titanium and chromium. Fig. 1 shows the two atomic arrangements known in iron; the diagrams are drawn to scale. Either of these modifications of iron may dissolve other elements in the solid state; by so doing, the temperature of the transformation is changed. In general 2-7, it appears that a solid solvent metal dissolves a metal solute by substituting foreign atoms in its own space lattice. Thus, iron may dissolve nickel in either of its crystalline forms by permitting an atom of nickel here and there to occupy the normal position

Jan 1, 1924

The underground storage of LPG and other hydrocarbons is in current commercial use in Northern Hemisphere countries in Europe, Asia and the USA.Elgas Pty Ltd, a 50 per cent joint venture between AGL and BOC, embarked on a worldwide feasibility investigation in 1989 to establish the viability of constructing an underground LPG storage facility in Sydney, Australia, the first of its kind in the country. Elgas recognised that with the limited 19 000 tonnes of storage capacity at Port Botany and the limitations imposed by use of small coastal ships (up to 10 000 tonnes capacity), a larger storage facility was required to utilise higher capacity ships from more remote sources such as the North West shelf and overseas. This would achieve security of supply in high demand periods and economies of scale. The underground option also provides improvements to safety and environmental standards.

Jan 1, 1999

By John W. White

Anthracite mine refuse, or culm dump material as it is sometimes called, is the waste material resulting from the sizing and cleaning of run-of-mine deep and strip-mined anthracite coal. It may also contain mine rock, carbonaceous shale, pyrite, and other debris from mining operations. This material is generally stored in piles or banks, some of which are over 100 years old. Many of the older banks contain a considerable amount of good coal, particularly in the finer size ranges, since these sizes did not have any particular economic value in the early days of anthracite mining. Today, the refuse material from a cleaning operation must be piled in an orderly fashion and in such a way as to minimize the tendency to ignite. There are well over 400 of these banks in the anthracite region containing over 1100 million tons of refuse located in the north-eastern part of Pennsylvania. The banks range in size from a few thousand tons of material up to as much as 13 million tons. Most of

Jan 1, 1972

By Joseph L. Uraco, Harry C. Verakis

The use of explosives in underground coal mines presents a potential risk for serious injuries and death to miners. Widespread disasters have occurred from the explosion of methane and/or coal dust initiated by blasting with explosives. Many of these disasters took place in the early 1900's when the use of black powder for blasting was prevalent. Historically, the investigations in the U.S.A. to develop and test safer explosives for blasting coal began in 1908 when a testing station was established in Pittsburgh, Pennsylvania. Since that time, great strides have been taken in the development of safer explosives. The use of safer explosives has significantly reduced blasting accidents in coal mines. Enactment of legislation, such as the Federal Coal Mine Health and Safety Act of 1969 and enforcement of regulations has also improved blasting safety. More recently, MSHA began a major revision of its regulations for blasting in coal mines. In 1988, MSHA published final rules for the approval and use of permissible explosives in coal mines. The approval requirements for explosives address testing and evaluation. The requirements include tests for sheathed explosives which represent a new technology. The use regulations provide increased safety protection for miners by including standards to address identified hazards. Major aspects of these standards, such as qualifications for blasters, multiple-shot blasting and the use of sheathed explosives are discussed.

Jan 1, 1992

By Jon Y. Kaneshiro, Gregory E. Korbin, Stephen J. Navin, Larry J. Stout

Sewage presently being discharged into the Tijuana River Valley pollutes the valley as well as the beaches in the South Bay of San Diego, making the beaches unusable nearly year round. The SBTO will convey flows down a 8.5 m (28 ft.) by 58 m (190 ft.) deep drop shaft, through a 3.35 m (11 ft.) by 5.8 km (3.6 mile) long tunnel, and up a 46 m by 2.7 m (150 ft. by 9 ft.) riser shaft connecting to a 1.5 km (0.95 mile) of seafloor pipeline and 1.2 km (0.76 mile) of diffusers on the ocean floor. The drop shaft will be sunk through 38 m (125 ft.) of saturated sands and gravels and 20 m (65 ft.) into the dense fine sands of the San Diego Formation. The tunnel liner has been designed as a five piece, single pass, gasketed, bolted, reinforced concrete liner designed to withstand an external head of 76 m (250 ft.) of water and internal operating head of up to 27 m (89 ft.) and to accommodate movement at the numerous fault crossings. The tunnel is contemplated to be driven with a state-of-the-art Earth Pressure Balance Machine (EPBM) or slurry shield machine through a wide range of conditions from clay to gravel with boulders.

Jan 1, 1995

By Richard R. Klimpel

In a process-oriented production environment, the first objective of any plant engineering effort is to safely produce sufficient product output with an existing plant layout to provide a profitable return to the plant owners and stable employment for plant employees. In such an environment, the terminology macro-engineering means looking at a plant from a perspective beyond "putting out routine fires" or "keeping the plant running." It means asking questions like: • What are the current equipment bottlenecks in the existing plant? • What portion of the plant is most sensitive to fluctuations in raw feed characteristics or other processing condition changes? • If one had X dollars to spend beyond routine maintenance, how could it be best spent to have the greatest impact on overall plant profitability? • What portions of the plant do we know least about? While these questions may seem obvious, they often go unasked due to time pressures, limitations on people or other resources and poor profitability of the existing plant. Even when the questions are asked, frequently a high level of personal bias or a lack of accurate information lead to less than optimal answers and sometimes a lack of confidence in engineering technology. Therefore, in a majority of process plants, there has been little serious change in the equipment layout or engineering operation practice since the start-up of the original plant design.

Jan 1, 1992

By A. J. Kauffman

This inventory of the industrial mineral resources of the Pacific Northwest indicates that each of the States comprising this great region annually produces nonmetallic materials valued at mans million dollars. Commodities or their products that have a large, localized market predominate. These include Portland cement, sand and gravel, stone, clay, and lime. The region's output of magnesite, vermiculite, pumice, and diatomaceous earth is outstanding. The magnesite deposits of Stevens County, Wash., are the largest and most important in this country. Mast of the domestic vermiculite production is obtained from deposits in Lincoln County, Mont. Oregon and Idaho rank third and fourth, respectively, as domestic pumice producers. Production data for diatomaceous earth show Oregon second and Washington fourth among the producing States.

Jan 1, 1952

The Electricity Generating Authority of Thailand own and operate an opencut mine supplying coal to on-site power stations at Mae Moh, 600 km North of Bangkok. The mine is being expanded from an annual production of 1.5 million tonnes per year in 1982 to over 9.5 million tonnes per year by 1991. The mine will be amongst the largest open pit operations in the world. It is technically difficult to operate and plan due to complex geology, weak strata and surface constraints including reservoirs, forests and traditional villages. This paper presents a case study of mine planning for the above project including associated collection and processing of geological and geotechnical information. The existing operation is described, as well as the strategy adopted for the mine at expanded production. The planning covers various phases of mine planning including a Conceptual Study, a Definitive Study and detailed short term planning. Each stage incorporated new information and reflected a higher level of confidence in the data and resulting plan. Sophisticated computer techniques were required including geological modelling, calculation of volumes, geotechnical analysis, scheduling and costing. The planning was undertaken on site by a team of Australian and Thai Engineers as part of the Thailand-Australia Lignite Mines Development Project which is a four year programme of assistance funded by the Australian Government.

Jan 1, 1986