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By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days' plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years' operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984

By M. L. Jeremic

Altered and unaltered coal from the Star-Key Mine near Edmonton, Alberta has been tested under compression and under tension. The test results showed that altered coal samples have an appreciably lower strength than unaltered coal. Altered coal samples do not give a linear load-displacement curve, peak strengths are poorly defined and yielding is observed over a range of loads, so the material can be regarded as relatively plastic. However, unaltered coal samples produce a linear loading curve with a high tangential modulus and an easily distinguished peak strength at which there is a sudden brittle failure. These findings lead to important differences in the theoretical design of ribs and pillars in underground mines in the two coal types. The substantial differences in the strength properties and behaviour of the two types of coal are governed by a higher intensity of cracks in the weathered coal. Two causes of the additional cracking can be suggested-subaerial weathering and subterranean weathering of the coal.

Jan 1, 1979

By L. E. Fischer

The background for the 630-million-dollar-plus iron ore project at Kudremukh is outlined. The system and plants for mining, crushing, concentrating, transporting via a slurry pipeline, filtering and shiploading 7.5 million metric tons of iron ore per year are fully described. The mode of operation and the problems encountered in such a transfer of North American technology to developing countries are analyzed. Difficulties encountered during construction are discussed and the progress milestones made over a two-year period are enumerated.

Jan 1, 1979

By P. D. Kondos, J. R. Goode

Given the global inventory of low grade and refractory gold deposits, processes that could turn these challenged deposits into mines are of considerable interest. Such gold deposits have low value and potentially high operating costs and so they pose special challenges for the mining engineer and metallurgist. Conventionally, refractory gold ores have been processed by whole ore pressure oxidation and roasting, or flotation followed by roasting, pressure oxidation or bio-oxidation of the concentrate. Halide-based processes have recently been developed that might be applied to concentrates. Low grade refractory gold ores have been processed using heap bio-oxidation followed by cyanide heap leaching or milling. Other processes are emerging. Barrick has completed an inventory of emerging technologies (1). A summary of the current status of these developments will be presented with the view that, with additional development, some of these technologies or a combination thereof may unlock the value of these deposits.

Jan 1, 2005

By James A. Robertson

"The Pronto Mine located at the east end of Lake Lauzon, Long Township, some 12 miles east of Blind River is of historic note being the discovery locality and the first producing mine of the Elliot Lake uranium camp. Radioactive bedrock was discovered in 1949, a commercial deposit was verified in 1953 and production commenced in 1955. Production continued to April 1960: total tons milled 2,264,404 from which 4,643,835 pounds U,O, were recovered at a recovered grade of 2.05 pounds U3O8 per short ton.The orebody is in a bed of pyritic quartz pebble conglomerate at the base of the Matinenda Formation of the Elliot Lake Group of the Huronian Supergroup. The rocks strike east and dip 15 degrees to 20 degrees south and unconformably overlie Early Precambrian granite, the upper surface of which is marked by a regolith. Several diabase dykes cut the orebody which is also affected by albite, chlorite, and carbonate-rich alterations. To the south the orebody is cut by a fault. The orebody is 6to 10 feet but locally 10 to 15 feet thick, has a strike length of 3,500 feet and extends down dip for 3,600 feet to a depth of 1,000feet. Some 300,000 tons of ore grade mineralization remain in the deeper portion of the mine.IntroductionThe Pronto Mine, (Photo I) at the east end of Lake Lauzon in Long Township some 12 miles east of Blind River, is of particular interest as being the discovery site and the first producing mine of the Elliot Lake camp.Production at the Pronto Mine commenced in 1955 and continued until 1960 when the mill was converted to treat copper ore from the nearby Pater Mine at Spragge. A description of both mines, based on material provided by the mine staff, was given in the report on ""Geology of the Spragge Area"" (Robertson, 1970).As little study has been done on Pronto geology or petrology since mine closure, the earlier description of exploration and geology is essentially repeated, but shortened, here- the main change being that the stratigraphic terminology has been amended as recommended by the Federal-Provincial Committee on Huronian Stratigraphy (Robertson et al., 1969)."

Jan 1, 1986

By T. H. Janes

"IntroductionSULPHUR is a constituent of many industrial products. It is part •of almost anything we eat, wear, or use. In fact, sulphur is so important that there has been an increasing tendency in recent years to measure industrial growth in terms of sulphur consumption.The uncertainty of obtaining adequate supplies •of elemental sulphur from the Frasch-mined domes. of Texas and Louisiana in the United States led all countries in 1950 to seek alternative sources of supply of this necessary element.Canadian industry has been supplied, for many years, with most of its sulphur requirements by United States Frasch-mined sulphur. World demand for this sulphur has necessitated the imposition of controls on its distribution, as production has not kept pace with demand. Until the third quarter of 1950, Canadian manufacturers of pulp and paper, heavy chemicals, explosives, and textiles •experienced little difficulty in obtaining their needs of elemental sulphur from the United States. However, at that time, low producers' stocks and declining reserves threatened to reduce shipments from producers, with the prospect of a continuing shortage for some time. These conditions, together with higher prices, stimulated the search for alternative sources of supply in Canada."

Jan 1, 1952

By Henk Dijkman, Wageningen University, Paula Gonzalez Contreras, Irene Sánchez-Andrea, Jan Weijma, Silvia Vega

"More than 20 years ago, Paques B.V. introduced innovative biotechnologies to recover metals and to remove sulfate from aqueous streams. These technologies find their origin in the exploration of microorganisms involved in the global sulfur cycle. Currently, several sulfur cycle biotechnologies are applied successfully at full-scale. The sulfur cycle is closely linked with the iron cycle, and also the latter offers opportunities for application of innovative biotechnology for the mining industry. Microorganisms of the natural iron cycle carry out reactions that are not feasible by chemical methods such as ferrous iron oxidation with oxygen at pH below 4. Iron oxidation with oxygen can be conducted using microorganisms living at pH between 0.5 and 7 and at temperatures between 0 and 95ºC. Remarkably these microorganisms can also carry out arsenite oxidation at similar acidic conditions and high temperatures. Making use of the extreme features of these microorganisms, Paques and Wageningen University have developed a biological process to precipitate arsenic as scorodite. This biological formation of scorodite is a novel combination of biological oxidation and biocrystallization. Depending on the level of saturation, biological oxidation rates and operational conditions, we could control the formation of the iron precipitates such as jarosite and scorodite. Currently new microorganisms have been harvested from hot springs and rock acid mine drainage to foster the growth of specialized microbial communities with potential high iron and arsenic oxidation capacities and higher resistance to other metals. In our paper we address the ongoing research and development of the bioscorodite process.THE USE OF IRON TO REMOVE ARSENIC In 2015 several environmental disasters related to the release of mine wastewater and tailings occurred. On August 5th, a waste water spill occurred from the Gold King Mine near Silverton, Colorado. A dam holding the tailing pond was damaged and spilled three million US gallons (11 ML) of mine wastewater and tailings, including elements such as cadmium, lead and arsenic, into Cement Creek, a tributary of the Animas River in Colorado. “At their peak, arsenic levels were 300 times the normal level and lead was 3,500 times the normal level” (The Guardian, 2015). In early November, another collapse of a mining dam in the Brazilian state of Minas Gerais spilled between ten and sixteen thousand US gallons of water and sediment after a dam failed from an iron ore mine. Arsenic and mercury polluted the Doce River, arsenic levels were found more than ten times above the legal limit in some places of the river (The Guardian, 2015). Waste production is inevitable during Mining. However, a preventive waste management strategy could have minimised waste production, maximised waste reuse and classified waste by their hazardous degree."

Jan 1, 2016

By A. Shaak

The town of Hedley is some 200 miles due east of Vancouver and lies in the bottom of the Similkameen River valley, at the junction of Twenty Mile creek, at about the 1,700-foot elevation above sea level. The Nickel Plate mine camp is on Nickel Plate mountain at an elevation of about 5,600 feet, four miles slightly east of north from Hedley, to which it is connected by 9 miles of road, and by 10,000 feet of tramway and electric railway. The latter is used both to transport the ore to the 275-ton mill at Hedley and to furnish the mine with supplies. History The Nickel Plate claim was staked in 1898 to cover the sole outcrop of the Nickel Plate system of orebodies. Soon afterwards it was optioned by the Marcus Daly interests of Butte and underground exploration commenced. Early exploration was successful, and a power plant, tramway, and mill were constructed. The mill began operations in 1904. Production under Daly control ensued from June, 1904, to August, 1909, and amounted to 167,000 tons. The Hedley Gold Mining Company was organized and commenced operations in 1909. The capacity of the mill was increased by stages to 200 tons and a steady production, except for short periods in winter, was maintained until 1930. By 1930, gold to the value of nearly $10,000,000 had been produced since the discovery in 1898. The South American Development Company optioned the property in 1932. Active exploration was conducted during 1933 and 1934 by the Kelowna Exploration Company, a subsidiary of the South American Development Company. This work was sufficiently successful that, coupled with the increase in the price of gold from $20.67 to $35.00 per ounce, production re-commenced in December, 1934, and continued uninterrupted until July, i946, when, along with all B.C. gold mines, a strike closed operations. Under the present ownership, the mill capacity was increased to 275 tons.

Jan 1, 1946

By Yuanming Pan, Brett Rogers, Baoquan Hu, Gary Yeo, Christine Austman

The nature and distribution of radiation-induced defects (RIDs) in quartz from the Maw Zone, a yttrium- and rare-earth-element-enriched sandstone breccia complex exhibiting intense hydrothermal alteration, have been investigated by electron paramagnetic resonance (EPR) spectroscopy. EPR spectra show that detrital quartz in sandstone, from five diamond drill holes intersecting the Maw Zone and one above the crest of the so-called Quartzite Ridge, contain only background-level RIDs, indicating that Ubearing fluids were absent in this area. However, close to the sandstone-basement unconformity, in hole WR-194 immediately west of the Quartzite Ridge, the concentration of RIDs in detrital quartz is significantly above background but at least an order of magnitude lower than those at the Key Lake and McArthur River deposits. Widespread drusy quartz at the Maw Zone, which signifies intense hydrothermal alteration, is associated with hematite-, sulfide- and carbonate-bearing mineral assemblages, which exhibit complex crosscutting relationships. EPR spectra of drusy quartz in all three types of mineral assemblages are low in RIDs as well, supporting the EPR evidence that fluids at the Maw Zone did not carry significant U. These EPR results suggest that, in spite of intense hydrothermal alteration and favorable structural geology, the Maw Zone is unlikely to host any significant U mineralization. Moreover, this study shows that the EPR technique is potentially a useful exploration tool, capable of determining whether individual alteration zones in the Athabasca Basin were associated with U-bearing fluids or not.

Jan 1, 2013

By Kurt F. Weitz

"The number of materials that can be classified as fillers covers an extremely wide range: this paper outlines those fillers of the industrial mineral type that find extensive application in the paint and plastics industriesIn the paint industry, mineral fillers are known as extender pigments. Extenders are added to paint and plastic compositions to (1) lower the cost and (2) rein-force or modify the physical properties of a composition.Commonly used extenders are classified according to chemical type and discussed in terms of the change in physical properties that they impart to a paint or plastic film. Available cost reductions and data on the consumption of extenders in the Canadian paint industry are also included."

Jan 1, 1970

By J. E. Shigley

The gemological properties that allow natural emeralds and blue sapphires to be distinguished from other gemstones are summarized in this paper. A variety of synthetic and laboratory-treated emeralds and blue sapphires are also encountered in the jewelry industry today. Gemologists distinguish these latter materials from their natural counterparts based primarily upon features seen with magnification, such as inclusions and/or growth zoning. In some cases, however, these observations and standard gem-testing methods are insufficient, and the use of non-destructive analytical methods, such as optical spectroscopy and chemical analysis, are required for positive identification. The commercial value of synthetic and treated gems are much less, and can be insignificant in comparison to that of an important untreated natural gemstone. Identification of synthetic and treated gem material is essential to maintaining integrity in the jewelry industry. Loss of consumer confidence in the gemstones sold at the jewelry counter could have a negative impact on the exploration and mining of natural emerald and blue sapphire.

Jan 1, 1998

By M. F. Goudge

ROCK wool, one of the most recent additions to the list of Canadian-made, insulating materials, is a soft, light, fibrous material consisting of interlaced, flexible, glassy fibres so exceedingly fine that, individually, they are almost invisible to the naked eye and will float in air. In the process of manufacture, a suitable rock, generally a self-fluxing argillaceous dolomite consisting of nearly equal proportions of acidic and basic constituents, is melted to a completely fluid state and then converted into fibres either by a blast of steam or air, or by a mechanical device. The increase within the past five years in the number of plants in the United States making rock wool and slag wool has been remarkable, especially in view of the depressed conditions prevailing 'with most industries during this period. In 1930, there were only 8 plants reporting production of .these materials, whereas at the present time there are 44 plants in the United States listed as making these products, and there are 3 plants in Canada. In 1929, the total sales of rock-wool products in the United States amounted to-$2,377,324. In 1934, according to the National Rock and Slag Wool Association, 26 member companies reported sales of $3,695,405, and in 1935 the sale's of 30 member companies had a value of $5,571,469. The establishment of the rock-wool industry in Canada followed the publication in 1931 of a report (1) by the Mines Branch, Department of Mines, Ottawa, in which was set forth the results of field work and laboratory studies which indicated that large deposits of rock in the Niagara peninsula, hitherto regarded as valueless, were suitable for the making of rock wool. This report was supplemented in 1934 by another report (2), giving the results of further laboratory and commercial-scale tests on the rock from these particular deposits, which proved conclusively that rock wool of good quality could be made from the rock in question.

Jan 1, 1936

By B. F. Osborne

"A new sensor cannot be considered in isolation from the process in which it is utilized. This paper, describing an on-stream particle size analyzer, therefore gives considerable emphasis to the slurry handling techniques employed to ensure that the instrument is presented with a representative sample. A new sampler is described, which continuously abstracts a small, representative sample from a closed pipeline containing a flowing slurry. This sample is then diluted, thoroughly mixed and pumped to a head tank, from where a continuous stream is fed at a constant rate to the size analyzer. Data are presented to show that particle size segregation is minimal throughout this sampling and sample preparation. A continuous particle size analyzer based on a separation principle is described, and the basic parameters of size distributions, and how they relate to this particular instrument, are considered. Typical results are given. An electronic system is presented which accepts the basic sensor outputs, and converts these to a particle size signal suitable for process control. Finally, the use of an inplant computer to process the sensor signals to obtain a particle size signal is briefly considered."

Jan 1, 1972

By R. P. Nicholson

On September 3rd, 1947, the Acadia Coal Company put into operation a central coal preparation plant. This plant was designed to process all coals mined by this Company in the Pictou County coal field. The problem, briefly, was to make a three-way separation of the raw coal fed into the plant. It was desired to remove all stone, metal, and wood from the marketable coal and to produce a splint coal from the raw material which would be suitable for making power. This splint coal product is belted directly to the power plant which is adjacent to the wash plant. To attain this object it was therefore necessary, first, to wash the raw coal, removing all splint, stone, metal, and wood. The stone, metal, wood, and highest-ash splint had then to be removed by a second washing in order to obtain the lower-ash splint for use in the power plant. The plant is on the east side of the Allan colliery, in the town of Stellarton (see accompanying photograph). It is of steel frame construction with wood siding, covered on the exterior with corrugated galvanized iron. Considerable concrete had to be poured for the foundation piers as the plant site is largely 'fill' ground. This necessitated the construction of extremely heavy footings containing a large amount of reinforcing steel. In all, 884 cu. yds. of concrete were poured for the various pits, tanks, and foundations; its average test was about 3,500 lb. per square inch. At the time the plant was constructed, the steel shortage in Canada and the United States was acute and, in order to obtain steel for the structure which is four stories high- an unused part of the Allan bankhead was torn down. Enough steel was obtained from this demolition to fabricate the new plant.

Jan 1, 1948

By C. R. Stelck

"AbstractThe Cardium formation of northeastern British •Columbia •contains an erosional unconformity that becomes progressively more severe northward until, •at Liard river, the stratigraphic hiatus eliminates the underlying Lower •Cardium sandstone, the Kaskapau formation, and the upper Dunvegan sandstones. The area of unconformity roughly coincides with the distribution of the continental facies of the earlier Dunvegan formation. Along Wapiti river, the zone fossil Scaphites ventricosus Meek and Hayden is found in the Bad-heart member of the overlying Wapiabi shale; Scaphites :preventricosus. Cobban marks the base of the Wapiabi shale; Scaphites cf. corvensis •Cobban is found in the middle shale member of the •Cardium formation. The log of the Red-Willow No. 1 well shows close similarity to the outcrop sections south of Wapiti river. The Cardium formation is mainly late Turonian in age. Two other pre-Cardium Turonian sands of north-eastern British Columbia are named the Wartenbe and Tuskoola sands.IntroductionTHE Upper Cretaceous Cardium (Bighorn) sandstone formation of the Foothills of northeastern British Columbia carries within its formational limits an erosional unconformity. The unconformity decreases to the southeast, becoming in immediate shoreline regions, now under the plains, a minor diastem. Such diastems, or stratigraphic intervals of non-deposition, occurring in the shallow unda-zone are paralleled in the deeper portions of the unda-zone by the phenomena of sub-aqueous winnowing. '.This winnowing and re-working •at critical depths creates sand areas with porosity."

Jan 1, 1955

By K. G. Baxter, D. G. Dixon

The Sepon process plant utilises an autoclave to oxidize a flotation concentrate containing pyrite, residual copper minerals, and sulphur. The concentrate is produced from the residue of a preceding atmospheric copper leaching circuit. The function of the autoclave is to provide iron and acid for that atmospheric copper leaching circuit. The key issues in the operation of the autoclave are to maximise the production of acid and ferric ions and to avoid scaling issues related to sulphur balling in the autoclave. Scale control in the autoclave was examined using various dispersants and residue recycle without success. Operation of the autoclave at high temperature and high acidity addressed the scale issue through rapid oxidation of the sulphur and produced a ferric sulphate precipitate in the residue that could be re-leached to provide ferric iron. This paper presents the development steps followed, through batch and continuous piloting that resulted in an autoclave circuit design that addressed the above process requirements. Following definition of the process design basis, modelling of the autoclave operation was carried out to assist with engineering design. The model included thermodynamics and kinetics of oxidation of pyrite, elemental sulphur and covellite and also considered gas/liquid mixing, oxygen solubility as a function of temperature and solution composition, ferrous to ferric oxidation, gangue reactions with acid and precipitation/re-dissolution of basic ferric sulphate and alunite.

Jan 1, 2004

By D. -A Tremblay

Dynamic wetting spread factors and interfacial heat transfer coefficients were determined for aluminum droplets solidifying on copper substrates, The spread factors were determined from the droplet geometries while the heat transfer coefficients were obtained by solving inverse heat conduction problems, 1-D and 2-D heat transfer models are presented and the results they provided are compared, For the latter, a sensitivity analysis was also performed to determine the influence of thermophysical properties and boundary conditions. Experiments were alternatively carried out with three different gaseous atmospheres and the dynamic wetting spread factors were correlated to the interfacial heat transfer coefficients.

Jan 1, 2005

By Werner Unland, Nick Holl

"The paper presents the engineering design and experience gained so far with a dewatering system for an open-pit uranium mine planned at Key Lake in Northern Saskatchewan.The results of hydrogeological investigations preceding engineering exhibit an extensive unconfined overburden aquifer hydraulically connected with the underlying Athabasca Formation and basement rocks, both of relatively low hydraulic conductivity. The overburden aquifer is embedded in a bedrock trough, with the deepest depression between the planned pits. The hydrogeological data were used in a numerical dewatering model simulating groundwater flow atdifferent stages of the pit development.Based on the model results, the engineering design had to provide for different pumping rates, varying between 1.0 and 0.21 ms/sec. This problem was solved by using a double line pressure system. The design concept for the complete peripheral discharge system and the well design used for 26dewatering wells are discussed.Experience with reverse-circulation techniques applied for the construction of the dewatering wells is presented. Theoretical and practical considerations which led to the constructionof wells of different diameters are discussed.The design of the in-pit dewatering system provides for seepage ditches, horizontal drains, pit-bottom sumps and inpit dewatering wells where required."

Jan 1, 1980

By R. P. Chapman

The geochemical interpretation of results of statistical analysis of published multi-element stream sediment data from southwest and northern New Brunswick is presented. Element concentrations in southwest New Brunswick are low and comparable to element concentrations in background areas in northern New Brunswick. Deposits of copper and nickel are indicated in southwest New Brunswick. Anomalous element concentrations occur in several areas in northern New Brunswick and the elements most commonly associated with these anomalies are Cu, Pb, Zn, As and Ag; and also Mo, Wand Sb. Bedrock geology greatly influences element concentrations and may cause false anomalies. Manganese has a pronounced effect on the dispersion patterns of Co and also Zn, Mo, Pb, As, Ba and Ni. Nickel and Cr are strongly sympathetically related and this association is independent of bedrock type.

Jan 1, 1977

By R. S. Boorman, H. G. Ansell

"Poor separation of lead from a copper concentrate of a major base metal producer was thought to have resulted from copper (0.2-0.4%) in the galena which caused it to float with chalcopyrite. No inclusions of copper mineral were detected which could account for the flotation of galena. The tendency for copper-bearing galena to float with chalcopyrite was confirmed by Hallimond-tube experiments in which the floatability of copper-doped synthetic galena (0.1-0.4% Cu) was approximately four times as high as copper-free galena. The difference in the cell edge (5.9338 ± 0.0003 A, Cudoped galena; 5.9361 ± 0.0002 A, Cu-free galena) indicated that the copper was lattice-bound and did not occur as submicroscopic mineral inclusions."

Jan 1, 1973