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By D. M. Baird

"Enormous deposits of gypsum of exceptionally high grade are readily accessible in southwestern Newfoundland. Coming large-scale production from one of these is resulting in renewed interest in deposits which have been known for more than a hundred and twenty years. General stratigraphy and structure of the Carboniferous rocks in which the gypsum occurs are de-scribed. The stratigraphic position of the basal gypsum-anhydrite zone is described. This massive evaporite horizon, which reaches a thickness of about 1,0001 feet, appears at Fishels-Heatherton, where it is largely undeveloped, and again on the nose of an anticline east of Flat bay, where a present production of 20,000 to 40,000 tons per annum is soon to be expanded to make it one of Canada's major producers. Detailed descriptions are given of the several types of gypsum, the relation of the gypsum and anhydrite, and the distribution of sodium chloride in the evaporite beds, and the bearing of all these on the origin of the gypsum are discussed. Brief reference is made to relation to world markets, mining and transportation, grade, and reserves."

Jan 1, 1959

By D. H. Wilson

"This paper examines the increasing need for mechanical-electrical people within the industry and some of the reasons why such a shortfall exists. It is suggested that, in part, it is image related. The present industry-education relationship in addressing the situation is examined and some thoughts are expressed on how these may be built on, in order to help solve the problem of attracting people to this critical area.IntroductionAs a long-time proponent of plant engineering and maintenance as a management function, I would like to review the progress made by the industry/ educational approaches in satisfying the needs in that area. In doing so, I would like to make the following points:1) that there has been an accelerating shortfall of mechanical-electrical people relative to the needs of the industry;2) that the condition will probably get worse before it gets better; ,3) that the past industry I educational approaches to alleviate the problem have met with limited success; and finally4) I would like to review some of the things being done and consider how these efforts might be extended."

Jan 1, 1981

By Mike Smith, George Chung

"A 23 million dollar Flotation Plant has been commissioned at the Iron Ore Company of Canada in 1998. Nine OK-50 cells &re used to float silica in this 1,400 tomes per hour plant. The paper details project development, construction and operating results. This plant gives IOC the capability to produce not only high quality blast furnace pellets of varying silica, CaO and MgO levels, but also a high iron, DR grade pellet. The first activity was simply to sit down with the suppliers, Outokumpu, Wemco. GL&V and Svedala, to discuss applications and share experiences. We learnt what each supplier had to offer, what features would particularly suit this application, what options were offered, what were the materials of construction, how the equipment is maintained, which wear parts require replacement, etc., etc. We tried to learn as much about the equipment as the suppliers themselves knew. Then we tried to learn more: we contacted users and asked about any weak points, which options were worth incorporating and which items were not. We then discussed these points with the suppliers and established how potential problems might be overcome."

Jan 1, 1999

By F. C. Grensing, W. R. Crib

Copper-15 Nickel-8 Tin alloy is a relatively modern material, having been discovered in the 1970’s. It has complexities with casting, hot working and interdependent solid state phase transformations. A key to the high reliability manufacture of wrought rods, bars, plates and tube is the casting technology, which limits segregation, promotes microstructural uniformity and enables hot working. The EquaCast® continuous casting process has enabled the production of a broadening variety of wrought forms with typical yield strengths ranging from 100 to 180 ksi (690 to 1241 MPa) depending on size, shape and temper. This paper reviews the characteristics of wrought Copper-15 Nickel-8 Tin products which have registration in AMS specifications (4596 and 4597) and MMPDS-04 (CN-1) for use in aircraft. The design limits, microstructures, fracture characteristics and tribological behavior will be examined. This alloy system is emerging as a material of choice for aircraft bearings, corrosion resistant oil and gas exploration components, machinery and demanding off-road equipment applications. ToughMet® 3 is an alternative or upgrade to conventional moderate and high strength aluminum bronze bearing alloys.

Jan 1, 2010

By The Staff

"THE Wabana iron ore mines, owned and operated by the Dominion Steel and Coal Corporation, Limited, .are on Bell Island in Conception bay, on the east coast of Newfoundland. Mining began on surface in 1895 and, although open-pit work is still done on a small scale, the entire output may be considered to•be derived from extensive submarine workings. In 1958 the average daily production of hematite ore was close to 12,000 tons, almost all of which was concentrated in a heavy-media plant. SUMMARYThe character, occurrence, and extent of the submarine bedded deposits enabled early operators to meet prevailing market demands with the minimum attention paid to exploration. Mechanization of the mine and the pressure for sustained high tonnages since 1955 have emphasized the importance of an expanded exploration and development programme.A serious handicap has been the impossibility of utilizing normal diamond drilling methods to explore ore conditions in advance of mining faces. Drilling between tl1e bedded zones has been done but the major difficulty has been to delineate ore reserves in the lower bed, which has the greatest ore potential of the three mineable seams."

Jan 1, 1960

By E. G. Joe

The continuing increase in costs for power and fuel are affecting significantly the cost of milling Canadian ores. In order to ascertain the scope and source of energy consumption in Canadian mills for further energy conservation opportunities, CANMET, in cooperation with the Canadian Mineral Processors, carried out a detailed survey on the metallic mineral processing plants. Sixty-seven mills representing almost 300 million tons of annual capacity participated in the survey. The results indicated that, in general, copper and iron ore mills, representing the bulk of the tonnage, consumed relatively low levels of energy per ton. Nickel-copper, zinc-copper and lead-zinc .ore mills were moderate in energy consumption, and uranium and some copper-lead-zinc mills reported much higher energy consumptions due primarily to the increased heat requirements of the ore pulp. Although plant heating costs varied somewhat with location, it was apparent that the lowest heating costs were achieved by those plants built with proper insulation and energy conservation design. If the cost per million British thermal units is taken as $2.00, the mill energy costs generally ranged from 40ft to $1.20 per ton.

Jan 1, 1979

By L Mariani, G. Mendoza-Suarez

In this investigation, TiH2 powders were coated with copper and nickel by electroless plating to delay hydrogen evolution. Copper-coated samples were found to have a mixed acicular (2D growth) and cauliflower (3D growth) morphology whereas the nickel-coated samples had a cauliflower morphology. Examinations of the coated powder cross-sections revealed that the coating thickness ranges from 0.2 µm to 4 µm. Uncoated areas on the powder surface and coating flakes unattached to TiH2 particles suggest poor adhesion between the coating and the substrate. The phase transformation undergone by the TiH2 during dehydrogenation was studied in samples taken at intermediary points in the heating cycles and examined by XRD. The findings reveal that as the powder is heated from room temperature to 800°C, it changes from TiH1.971 to Tiu and to aTi. Differential Thermal Analysis (DTA) was performed to study the effects of the coatings on the temperature of hydrogen release. It was found that increasing the number of plating iterations, and therefore the thickness of the coating, creates a significant shift in the temperature of gas release.

Jan 1, 2006

The primary steel industry of the Prairie Provinces consists essentially of three companies whose total annual melting capacity, as of January 1, 1963, was 333,000 net tons. These companies have steel rolling facilities. In addition, there are five other companies producing steel castings by melting scrap in electric furnaces which, with the plants having rolling facilities, gives a total annual furnace melting capacity of 380,000 tons. Since 1954, the annual production of steel ingots and castings has ranged from a low of 66,588 tons, in 1954, to a high of 211,138 tons in 1961. The present facilities on the Prairies for making steel ingots from scrap, and rolling them to produce light merchant mill products, appear to be sufficient for many years ahead. Steel scrap, as electric furnace feed to make steel ingots for the present line of products, will probably continue to be available at reasonable prices either on the Prairies or from the north-central United States. It is recognized, however, that residual elements in scrap may be-come of greater significance and necessitate more rigid control of scrap quality.

Jan 1, 1963

By F. N. Smith

The carbon steel casings of Heat Recovery Steam Generators (HRSGs) in a co¬generation plant were found to have developed cracks that originated on the inside surfaces. The HRSGs receive hot exhaust gases from the primary Gas Turbines (GTs), which are fuelled with pipeline natural gas. The GTs was initially operating without any suppression of nitrogen oxides (NOx). After being in service for about two years, some of the cracks were found to have penetrated right through the 1/4 in. thick casings. The casings are fitted with insulation on the inside (hot gas side). Examination of steel samples cut from the casing walls revealed (i) fine cracks propagating through the steel from the inside surfaces, and (ii) the presence of relatively large amounts of nitrate ion on the inside surfaces. It was concluded that the nitrate ions originated from nitric acid that was condensing on the relatively cool walls of the casings behind the insulation. Nitric acid was formed in the GT exhaust gases by the combination of water vapour (formed from combustion of the hydrocarbon fuel and from moisture in the combustion air) and nitrogen oxides (formed from nitrogen and oxygen in the combustion air).

Jan 1, 2005

By C. R. Ross

"THE ASSESSMENT of pneumoconiosis-producing dusts in mines and other industries is usually undertaken for one or more of three reasons: (1) To compare dust exposures at particular operations with standards of permissible dustiness in order that hazards may be evaluated and preventive procedures initiated where required.(2) To study particular operations with the objective of improving dust control devices or procedures by locating dust sources. (3) To obtain data which, along with the results of medical investigations, may assist in understanding the causes of dust-induced diseases or aid in the establishment of permissible standards of dustiness. Most dust measurements are made for the first of these reasons -to evaluate dust hazards so that they may be controlled. For this purpose, four quite different assessment techniques have been in widespread use for many years. One of these is based on the konimeter, an instrument familiar to most .Canadian mining men; a second on the impinger, which is also widely used in Canada, and almost exclusively so in the United States; a third on the thermal precipitator, used extensively in Britain and South Africa; and a fourth on the tyndallometer, a light-scattering instrument used in Germany."

Jan 1, 1960

By Roland B. Hoag, Roger G. Webber

Sulphate concentration in groundwater is a good measure of the extent of oxidation of sulphides, provided that sulphide minerals are the primary source of the sulphate. A study was conducted near the Eustis Mine in Quebec to determine where and how the sulphate in groundwaters originated. Atmospheric precipitation is the only source of sulphate other than oxidation of sulphides, and in this study area it is equal to 0.01,. millimole per litre. The oxidation of sulphides can be divided into subsurface oxidation (mainly inorganic processes) and surface oxidation (including both organic and inorganic processes) . The maximum sulphate concentration due to subsurface oxidation of sulphides depends on the solubility of 0 2 in water and is 0.25 millimole per litre. Surface oxidation is, therefore, responsible for any amount greater than atmospheric plus subsurface contributions (0.29 millimole per litre). Surface inorganic oxidation occurs in waters with a pH greater than 15 and is controlled by the kinetics of the oxidation processes. Organic (bacterial) surface oxidation is dominant only in acid (pH< 1.5) waters. The bacterial action accelerates the oxidation of sulphides, and large quanttties of sulphate may be introduced into solution.

Jan 1, 1976

By Lionel A. York

THE first application of the cementation process took place in the year 1864, according to H. Standish Ball, when a break in the brickwork lining at a depth of 270', in one of the Rhine Preussen pits near Homburg, was sealed by running in milk of cement from the surface by means of a small hand pump. At about the same time Monsieur Portier adopted the method in France for repairing breaks in shaft lining. Figure 1 is descriptive of the Portier system and is of interest when compared with modern practice. During the next thirty years numerous attempts were made to improve the process; the general method used in sinking being to put clown bore holes outside the perimeter of the shaft for the purposes of injection. The cementation process was first recognized as an important as-set to mining in 1896 when Monsieur A. Francois developed his method of boring and injecting inside the shaft below the permanent water level. The Francois cementation process rapidly attained fame on the Continent and many shafts were sunk by its use in France, Belgium and

Jan 1, 1961

By Stavros A. Argyropoulos, Radhakrishna Valiveti, Bernard Closset

"The use of microprocessors in metallurgy is currently increasing at a very fast rate. A large number of companies are offering systems ""off the shelf"" which are aimed at the data acquisition and process control market. There are two main drawbacks to these systems: first, they are usually quite expensive, and second, they are not completely compatible with the target metallurgical application. An alternative is to develop a microcomputer-based system "" in lab "".A dedicated microcomputer system has proved to be very useful in many metallurgical research applications(1,2)). However, in this system the analog input signals had to be transferred over long distances , and significant noise was introduced despite the use of shielded cables. In order to overcome this problem a network of low pass-filter s was designed and built. The usage of the abovementioned system brought the need to digitize the analog signals in-situ and transfer the digital signals, which are much less susceptible to noise over very long distances. This distinctly different design philosophy has become a reality with the evolution of microprocessor technology over the last few years. This design philosophy is utilized in this development."

Jan 1, 1984

By W. R. Bacon

"MAGNETITE HAS BEEN found in many .parts of the coastal area of British Columbia, but the more important deposits are on Vancouver Island and Texada Island. The locations of these deposits are shown on Figure 1.Interest in the magnetite deposits dates back to the 1870s, when land was acquired on the southwest coast of Texada Island by the Puget Sound Iron Company. This ground included the Prescott, Paxton, and Lake deposits. During the years 1885 to 1903, and 1908, 28,898 tons of magnetite ore was shipped to the company's blast-furnace plant at Irondale, Washington, U.S.A. This production was almost entirely from the Prescott open-pits.In the years following the Texada Island discoveries, other magnetite deposits were found in the coastal area, and various plans were proposed to utilize the local ores in the establishment of a steel industry in the Pacific Northwest. None was carried to fruition but, in 1951, open-pit mining was begun at Iron Hill, Vancouver Island, to furnish iron concentrates for steel mills in Japan. In 1952 mining of the Texada deposits was resumed to supply the same market. Production figures for these recent operations are as follows:"

Jan 1, 1949

By P. R. Geoffoy, T. Koulomzine

"The discovery of the Mogador deposit concealed by 100 feet of overburden was the result of combined application of geological reasoning, ground geophysical surveys, studies of glacial float and extensive diamond drilling. The ground was acquired because it lay on the projected intersection of the Manville and Laflamme River faults. Systematic ground prospecting led to discovery of mineralized floats. A first unsuccessful exploration campaign lasted several years and consisted of 137 drill holes.In 1951 the boulder nests were reexamined and an associat'on of the mineralized float with boulders of a granodiorite, unknown in outcrops of the district, was established. Consequently, ground magnetic surveys were extended and re-interpreted, and a large anomaly interpreted as corresponding to a batholith was outlined. The existence of the batholith was immediately confirmed by drilling and the Mogador deposit discovered in third hole of new drilling programme in a zone of fractured volcanics paralleling southern contact of batholith.The Mogador deposit is a complex replacement of silicified volcanics by pyrite, pyrrhotite, sphalerite, chalcopyrite and galena carrying values in silver and gold. A total of 1,230,000 tons has been indicated, most of it now classified as fully developed proven ore."

Jan 1, 1960

By A. Desbiens, A. Pomerleau

During the summer of 1994, a new PID-based control strategy was installed on line B of the grinding circuit at the Kidd Creek Division of Falconbridge Ltd. Part I of this paper described the methodology used to select the appropriate control strategy using a phenomenological dynamic simulator. Part II presents the implementation of the control strategy. Prior to the controller installation, it was necessary to solve various problems related to the process, such as a cyclic behaviour of the rod mill feed tonnage, a problem related to the mill water source and the calibration of the flowmeters. Once these problems were solved, the control strategy was accomplished in two steps. Step 1 corresponds to the installation of control loops to regulate the pump box level and the cyclone overflow density. Step 2 describes the implementation of a loop to control the cyclone feed density. According to Part I, a loop to control the circulating load is also part of the original design. However, reasons are given to explain the rejection of this loop. For both steps, technical procedures such as filtering, process identification and controller tuning are detailed. Finally, the operator’s interface is briefly described.

Jan 1, 1997

By G. R. Guillet

THE LATE Dr. D. F. Hewitt, Ontario&apos;s foremost authority on industrial minerals, was the first to point out the importance of urban minerals when he produced figures (Hewitt 1968) to prove that the Toronto-Hamilton area was Ontario&apos;s second largest mining camp in 1966 (Fig . 1). In that year, the value of mineral production within a 60-mile radius of downtown Toronto exceeded individually that of Steep Rock, Kirkland Lake, Timmins, Manitouwadge and Elliott Lake. Only the nickel and precious-metal production of Sudbury .surpassed in value that of Toronto&apos;s pits and quarries. Although that position was unchanged for some years during the early sixties, it was admittedly an unusual situation: gold was still pegged at an artificially low value; uranium was stagnant; and Texasgulf had not entered the scene. However, the point had dramatically been made. The combined value of production from hundreds of sand and gravel pits and dozens of limestone and shale quarries was of formidable proportions. The mining industry of the urban fringe could not be denied. Construction aggregates, cement, building stone and bricks were fueling an apparently insatiable appetite for urban expansion and redevelopment.

Jan 1, 1978

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 F. R. Archibald

IN a recent paper on Roasting of Beattie Concentrate (1), the importance of controlling the temperature, and the sulphur dioxide concentration was pointed out. It is the purpose of the present paper to present further information by which the most satisfactory conditions for roasting are more specifically defined. Incidentally, a method of illustration is developed for representing roasting curves on a three-dimensional diagram. The primary purpose of this investigation, as in the case of the earlier work, was the search for information that would be of practical value in improving plant operation and gold recovery. For this reason, emphasis is laid on the regulation of essential variables and on definition of their optimum values and limits for maximum gold recovery in the subsequent cyanidation process. Good roasting is considered at least as much an art as it is a science, and, in this light, theoretical consideration of the nature and sequence of the chemical reactions involved is of secondary importance. The presentation which follows includes a series of graphical illustrations, an interpretation of the graphs, some theoretical considerations, and a description of laboratory technique.

Jan 1, 1940

By R. H. Duthie

As at any other mine in Canada, grade control procedures are used at Steep Rock Iron Mines (1) in order to ensure that concentrator and pellet-plant operator s have a uniform feed so that they can manufacture a pellet to suit buyers&apos; specifications and (2) to maximize ore recovery so that as little as possible finds its way to the waste dump or is downgraded by contamination. At Steep Rock, material grading 40% to 66 % Fe is considered ore. The ore may contain up to 10% sulphur. These ranges create six different stock pile types, with the possibility of more if large concentrations of arsenic are encountered. Although grading and mining techniques used to accomplish these ends are fairly standard, there is an appreciation and willingness by hourly and staff pit personnel to make grade control effective. This produces vertical and horizontal communication, which is necessary for success in this field. At Steep Rock, the waste-to-ore ratio is greater than at any other iron ore mine in Canada. Also, a high percentage of the ore mined is direct pellet feed. For these reasons, .grade control is very important.

Jan 1, 1977