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By G. H. McKay

AT the Eagle mine, near Gilman, Colorado, where the Empire Zinc Company have installed an underground mill, transportation problems were comparatively simple. A railway siding on the Denver and Rio Grande railway is equipped with an unloading dock or platform at the portal of their service incline adit to the mill. This 18-degree incline is approximately 600 feet long from the unloading track to the head of the mill skipway. For the Big Missouri mill, upwards of 2,500 tons of material and equipment had to be trucked from tidewater at Stewart, B.C., a distance of 21 miles to the Big Missouri camp at elevation 2,800. From that point, this freight had to be moved either over or through the Big Missouri ridge, rising to elevation 3,450, to its final location 800 feet from the surface between elevations 2,150 and 2,350. Immediately after leaving the government dock at Stewart, the road crosses the International boundary line into Hyder, Alaska, and then follows a water grade for eleven miles along the lower stretches of the Salmon river. leaving the river, the road climbs for two miles before crossing back into British Columbia territory at Silver Heights, and then continues for another mile and a half to where the Big Missouri road branches off from the main road to the Premier mine. For a distance of four miles from the junction of the roads, the Missouri road is very narrow, with many sharp curves and with irregular up and down pitches and grades up to 25 per cent until it reaches the Summit. From there on, a fairly easy grade leads a mile and a half to the end of the road on Joker Plats. In winter, the last stretch of road is subject to heavy snow drifting, especially through a narrow funnel-shaped gulch, known as 'The Gap', where the snow may pile up to a depth of over twenty feet.

Jan 1, 1938

By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT: As part of an overall study of properties and processes influencing consolidation of oil sands fine tailings resulting from different extraction processes, self-weight consolidation tests were per-formed. Fourteen 2 m and 1 m high standpipe tests were instrumented to monitor the rate and magnitude of consolidation of seven fine tailings materials. Tests provided valuable information about the variation of consolidation related to differences in fine tailings material properties that result from a change in bitu-men extraction process (caustic versus non-caustic). In addition, the effect of adding a coagulant to caustic fine tailings was measured. Test results are presented and discussed in terms of consolidation rate long-term volume decrease, compressibility, and downward drainage. Non-caustic fine tailings had fasterinitial consolidation, which is important in tailings ponds for reducing storage capacity and returning decant water at a faster rate to the extraction plant. Similar results were obtained for caustic fine tailings with a coagulant addition. However, long-term settlement of the different fine tailings appears to con-verge to a similar value over time because it is then governed by effective stress.

Jan 1, 2011

By P. Mundell, R. Torbin

"There are many physical and operational obstacles in pipelines that make the passage of inspection robots impossible including:•,Small radius bends•,Low operating pressure•,Plug valves•,Large changes in pipe size•,No permanent access to the pipeline.The inspection of unpiggable pipelines requires the marriage of a highly agile robotic platform with NDE sensor technology operating as an integrated system. Foster-Miller and GE/PII are developing a robot that is essentially a battery powered, train-like platform. Both front and rear tractors propel the train in either the downstream or upstream direction. Like a train, the platform includes additional ""cars"" to carry the required payloads. The cars are used for various purposes including the NDE sensor module(s), the power supply, and data acquisition/storage components. The robot is designed with a slender aspect ratio and the ability to change shape as required by the physical obstacle presenting itself. The MFL sensor module must also morph itself through the physical obstacles, and thus, will require some level of segmentation. The segmented MFL magnetizers and transformable sensor module represent a major advance in the science of sensor technology and pipeline inspection."

Jan 1, 2005

By V. “Ram” Ramachandran

"In view of the increasing number of environmental regulations that have been promulgated all over the world in the last thirty years, non-ferrous smelters and refineries have had to learn and adapt to treating process bleed waste streams containing heavy metals. The result of such treatment invariably yields a gypsum-saturated solution containing salts such as alkali metal sulfates, chlorides and fluorides. Presence of anions such as sulfates, chlorides and fluorides in the discharge streams – presently not a major problem- are coming under increasing scrutiny and will have to be addressed in the near future. It is envisaged that discharge limits for sulfate ions will be in place in the near future. Treatment of brackish water to produce drinking water also results in brine streams containing alkali salts that have to be addressed for proper disposal. This paper reviews treatment options for such streams containing high levels of total dissolved solids with emphasis on sulfate removal. Areas covered would be: a) chemical treatment for removal of various constituents that make up the total dissolved solids b) processes for sulfate removal processes –thermal and non-thermal-to recover and reuse of treated water and c) brine use and treatment options.INTRODUCTIONThe rising cost of water and meeting the ever-changing stringent environmental discharge regulations make water recycling and reuse essential. The metallurgical industry has used water as a medium for dissolving and/or rejecting metals and chemicals in addition to removing thermal energy. Any excess process effluent is collected and sent to end-of-pipeline treatment and ultimately discharged to surface water for disposal under a permit. The conventional- and probably the cheapest way -of treating metal-bearing process effluent streams is lime neutralization followed by sulfide polishing for elimination of heavy metals to produce a stream that meets NPDES discharge limits. This results in a stream containing dissolved solids.These dissolved solids normally comprises of inorganic salts. The possible constituents are cations calcium, magnesium, sodium and potassium. The anions are sulfate, chloride, fluoride, nitrate, carbonate and bicarbonate. In addition to these constituents, the treated effluent streams contain very small amounts of heavy metals, oxyanions such as arsenites, arsenates, selenites and selenates. Process streams from gold operations contain residual cyanide. Small amounts of ammonium ions are also present in these streams based on the pH of the solution."

Jan 1, 2012

By L. E. Djingheuzian

Introduction For many years the immense deposits of bituminous sands of northern Alberta have been attracting the attention of our governments, engineers and .scientists ( 6). Undoubtedly these bituminous sands represent one of the greatest potential resources of liquid fuels in the world. However, their commercial development has been retarded by the complexities of the technological problem and by the economic factors involved in the processing of the sands. The technological problem has been attacked from several angles ( 2, 3, 1, 11), and cold water separation of bitumen is one of them. To the ore dressing engineer, the cold water process is of utmost importance since, by the use of standard ore dressing machinery, it accomplishes most efficiently and economically the separation of bitumen from bituminous sands. The significance of using ore dressing equipment was especially enhanced by the fact that the scientific principles which underlie the design of standard machines were demonstrated in the cold water separation process with an extraordinary clarity. This greatly facilitated the analysing of limitations and advantages of different machines during-the pilot plant investigations and helped to complete the investigations practically in the allotted time.

Jan 1, 1952

By W. L. Brown

"The Normetal mine is about 7 miles east of the Ontario-Quebec boundary, and 13 miles north of the town of Dupuy on the Canadian National railway. The mine workings are largely on lots 44 and 45 in the south half of range 10, Desmeloizes township.The surface outcrop is reported to have been discovered by a trapper previous to 1925, but the details are obscure. The property was originally owned by the Canadian Exploration Company of Amos, Quebec, and was later transferred to Abana Mines, Limited. The latter Company carried out underground work from two shafts down to the 550-foot level. The property was acquired by Normetal Mining Corporation in 1931 and was reopened in 1933, when development work was carried down to the 800-foot level. The mine was closed down in 1935 because metal prices did not justify production at that time. It was reopened early in 1937 and milling commenced in September of that year. To the end of 1945, a total of 1,497,- 169 tons of ore was milled from which was produced 184,533 tons of copper concentrates containing 84,738,368 lb. copper, 2,744,100 oz. silver, 26,230 oz. gold, and 153,524 tons of zinc concentrates containing 163,752,433 lb . zinc."

Jan 1, 1954

By O. A. Ojo, D. L. Chen, N. Zhou, J. Q. Zhang, A. K. Khan

Dual phase (DP) steels are designed to consist of hard martensite dispersed in a relatively soft ferrite matrix, which offers a favorable combination of high strength with good deformability. Fiber laser welding (FLW) is becoming increasingly important for joining advanced materials due to its flexibility and deep penetration. In this study, the microstructure of a dual phase steel, DP980, welded by FLW technique was carefully analysed. Gleeble thermo-mechanical simulation coupled with analytical transmission electron microscopy (TEM) revealed that the FLW process produced significant microstructural changes in a narrow heat affected zone (HAZ) and fusion zone (FZ), which can result in dramatic changes in mechanical properties. This is reflected in the micro-hardness profile obtained across the welded material. The salient phase transitions induced by the FLW, including the formation of new martensite grains in the upper-critical HAZ and FZ, are discussed.

Jan 1, 2014

By Jason Berenyi

Presentation Overview ? What is Potash? ? Where are the potash deposits? ? Current potash mines ? production, capacity and planned upgrades ? Saskatchewan Saskatchewan?s Potash Production Potential s ? Current Status of Potash Exploration ? Increasing Demand for Potash ? Saskatchewan global role

May 1, 2009

By P. Scinto, P. Hudson

"Modern day ore bodies are becoming increasingly harder, more abrasive and lower grade. The Mako deposit is located in Senegal and consists predominantly of primary mafic and felsic lithology that are both very competent and very abrasive ores (Axb < 30, BWi >20 and Ai >1.0). The deposit was initially discovery in 2010 and the Toro Gold management team fast tracked the Mako Project through development and into production to achieve its first gold pour in January 2018. The comminution circuit comprises primary crushing single stage SAG milling with recycle crusher (1oCR SS-SAC). The mill reached design throughput and grind size seven weeks after first ore. The Mako project marks another successful international application of single stage milling, which represents a simple and easy to operate comminution circuit for small-to-mid size projects with a low capital cost. This paper describes the ore interpretation, comminution modelling, grinding circuit selection and design, as well as an overview of the commissioning and ramp-up of the mill.INTRODUCTION The Mako Gold Project is operated by Toro Gold Ltd., which holds a 90% interest in the project. The project is located in south-eastern Senegal in the Kedougou region, close to the Gambia river and township of Mako. The Mako deposit lies in the “Kenieba Window” of eastern Senegal and western Mali, which hosts a number of gold mining operations and development projects. The Mako Gold Project has an estimated life of 8 years with overall recoverable gold estimated at 924 koz. The process plant is designed to treat 1.8Mt/a of ore and produce 128 – 143 koz of gold per annum. Lycopodium Minerals Pty Ltd (Lycopodium) was appointed to provide feasibility studies and EPCM services for the greenfield project. Forming part of consultancy services provided by Lycopodium, Orway Mineral Consultants (OMC), a subsidiary of Lycopodium, was involved in the design, commissioning, ramp up and ongoing post commissioning support of the comminution circuit."

Jan 1, 2019

By Scott Honan, Tassos Grammatikopoulos, Mike Johnson, Kelton Smith, Niels Verbaan, Ernesto Bourricaudy, Eric Larochelle, Rick Sixberry

"NioCorp is developing the niobium/scandium/titanium Elk Creek carbonatite resource deposit. The carbonatite phase contains significant niobium (0.71% Nb2O5), titanium (2.68% TiO2) and scandium (72 g/t) and is composed predominantly of calcite, dolomite and ankerite. Niobium is mostly (80%) contained in the pyrochlore and the balance in various Fe-Nb-Ti oxides, which also host most of the titanium. Scandium is distributed homogeneously throughout the ore mineral assemblage. The process flowsheet recovers separate niobium, titanium and scandium products. Scandium is extracted from whole ore hydrochloric acid leach solutions through solvent extraction, and is further refined through a re-leach and precipitation process. Scandium leach residues are treated with sulphuric acid to recover separate niobium and titanium precipitates. Both hydrochloric acid and sulphuric acid reagents are recycled within the flowsheet. This paper will discuss key bench and pilot test results (focusing on the scandium flowsheet) and will present a conceptual flowsheet developed by the project team for NioCorp at SGS Minerals.INTRODUCTION NioCorp is developing North America's only niobium/scandium/titanium project. The Elk Creek project is located near Elk Creek, Nebraska, and is the highest grade niobium project in North America and the largest prospective producer of scandium in the world. These elements are unique and valuable superalloy materials that are strategic and critical to many industries and national defense technologies. The project includes the Elk Creek Carbonatite (the Carbonatite) that intruded older Precambrian granitic and low to medium grade metamorphic basement rocks. Both the carbonatite and Precambrian rocks are interpreted to be unconformably overlain by approximately 200 meters (m) of Paleozoic marine sedimentary rocks of Pennsylvanian age. As a result of this thick cover, there is no surface outcrop within the Project area of the carbonatite, which was identified and targeted through magnetic surveys and confirmed through subsequent drilling. The available magnetic data indicate dominant northeast, west-northwest striking lineaments, and secondary northwest and north oriented features that mimic the position of regional faults parallel and/or perpendicular to the Nemaha Uplift."

Jan 1, 2017

By T. C. Cheng, G. P. Demopoulos

It is the object of this paper to discuss various options for improving the hematite process in terms of increased throughput hence lower capital cost and production of saleable quality hematite. With reference to increasing the throughput of the process, it has now been determined via the analysis of Akita Zinc Co&apos;s continuous industrial autoclave performance data that the process kinetics is limited by the rate of the hydrolytic precipitation reaction. By correlating the hydrolytic precipitation rate to supersaturation ratio, it is shown that accelerated kinetics can be achieved via the following measures: (1) in-situ neutralization with addition of zinc calcine; (2) elevation of temperature; and (3) dilution of feed; of which, the first one was retained for further evaluation. According to presented estimates, addition of calcine, amounting to only 2.6% of the total zinc calcine processed, can allow for shortening the retention time by at least 50%. Such drastic shortening of retention time may be either used to increase the throughput of a given autoclave circuit or alternatively to release autoclave capacity for clean hematite production. Hydrothermal treatment of the crude hematite product proved effective in producing clean hematite as according to laboratory tests, hence allowing the sulphur content of hematite to be reduced from around 4% to less than 1%. A conceptual flowsheet incorporating in-situ neutralization for accelerated kinetics with hydrothermal upgrading of crude hematite without sacrificing production capacity and with minimum upset of the plant&apos;s water balance is described.

Jan 1, 2004

The Daly-Judge Tunnel, begun in 1887 to drain mine workings, is now a source of potable water for the Municipality of Park City. The water is exceptionally clean; however, when roof falls occur, suspended solids levels become too high and water from the tunnel cannot be used in the treatment plant. In 2001, the tunnel was inspected and rehabilitated to ensure that the water supply for the 2002 Winter Olympic Games would be uninterrupted. Twenty-five timber tunnel sets were removed, and 86 steel sets were installed. Timber lagging was installed or replaced over about 230 m (750 ft) of tunnel length.

Jan 1, 2006

By N. Bahrani

Photogrammetry surveys were used to document a footwall slab failure that occurred at a surface coal mine located on the eastern slope of the Rocky Mountains. Photographs taken before and after the failure provided the pre- and post-failure geometry of the slope and the failed slab. A 2D finite element model was constructed using slope profiles. The model contained joint elements that represented the bedding surface upon which the slab slid and the model was used to analyze the footwall slope. The in situ stresses, rock properties and the bedding surface shear strength and stiffness properties are discussed. The process of mining out a valley and exposing a highwall was modelled. As expected, elastic valley rebound occurred in the model, but shear stress and shear displacement reversals along the slip surface were also observed. The modelling results provided new insight into shear strength degradation that occurs when the pit floor approaches and then passes a specific point in the highwall.

Jan 1, 2009

By M. Melashvili

"The SART Process was introduced to the gold mining industry in the late 1990s and several commercial plants were built over the following 10 to 15 years. Most of these plants have operated well and enjoyed plant performance in line with expectations based on the underlying chemistry of the process. However, two of the plants have consistently suffered from high reagent consumption and poor product quality, which has motivated a re-examination of the process fundamentals.The primary product in the SART Process is synthetic chalcocite, Cu2S, and the stoichiometric requirement for sulphide addition is therefore 0.5 moles per mole of copper in solution. It is shown here that when sulphide is added in excess of this amount (generally with the express purpose of lowering residual copper in solution) it not only fails in its intended purpose, but can have a negative impact on the settling and filtration characteristics of the copper sulphide product, as well as the final product quality. Moreover, these problems are exacerbated the higher the selected operating pH in the pH 3 to 5 range, and the longer the residence time of slurry in this pH range.Freshly precipitated copper sulphide compounds are known to be very fine and slimy, with poor settling and filtration characteristics. It is therefore important to engineer the SART Process in such a way as to encourage growth in the average particle size of the precipitate crystals. This was the rationale for recycling a portion of the thickener underflow to the primary reactor when the SART Process was developed. However, the theory of crystallization predicts that compounds of extremely low solubility, such as chalcocite (Cu2S: KSP = 10-48), are unlikely to experience growth in crystal particle size through heterogeneous nucleation and are more likely to grow through aggregation. On this basis, the SART practice of recycling a portion of thickener underflow to the primary reactor in the commercial plants is unlikely to lead to crystal growth via nucleation, and could in fact promote breakage of the aggregates that formed in the thickener. Recycling thickener underflow could therefore have the opposite of the desired outcome. The result of testwork that is reported here lends credence to this theory and questions the wisdom of recycling in the SART process."

Jan 1, 2016

By A. Brown

"The first printed report on Canada's coal resources was published in Paris in 1672(1. Written by Nicholas Denys, then Governor for France of Isle Royale (Cape Breton Island), the report dealt exclusively with the coal of the Atlantic region because little or nothing was known about the interior of North America. Clearly, also, he wrote about a resource of which much was known among the military and early settlers of that day. This early knowledge is not surprising because the presence of coal is clearly displayed in the coastal cliffs of Cape Breton as it was also, at a later date, to the first arrivals on Vancouver Island.An example of early use was that of the French garrison at Fort Louisburg in the first half of the 1700s. Still earlier, in 1643, Governor Winthrop of New England reported the receipt of a small ship load of coal from New Brunswick (2). Despite this early knowledge there was no significant development of coal mines until the 1800s. This had to await the ending of wars between the French and British factions and the growth of population. Basically, also, its development awaited the beginning of the Industrial Age. Organized coal mining began in Canada in 1825 with the formation of the General Mining Association. This British firm was the creation of a group of London jewellers which had been granted royal rights, by the British crown, to all minerals in Acadia (substantially the present Maritime Provinces). The Association took over a number of existing small mines and opened up larger operations in the Sydney coal field. Subsequently, it expanded to the mainland Nova Scotia fields at Stellarton and Springhill. The Association continued in existence as the major coal producer in Canada until 1899 when it sold its properties to the Nova Scotia Steel and Coal Company, Limited (3). This Montreal-based firm managed the coal mines as a major Canadian producer of coal until 1968 when financial problems led to the expropriation of the mines by the Government of Canada. The federal government established the Cape Breton Development Corporation to operate the larger mines on Cape Breton Island. This Crown corporation continues to be a .major producer of coal in Canada."

Jan 1, 1985

By W. D. Sinclair, R. J. Cathro, E. M. Jensen

"The Cash is one of the largest porphyry copper-molybdenum Deposits found in Yukon to date. It is 80 km northwest of Carmacks, within the unglaciated portion of the Dawson Range, and is associated with the Big Creek fault, an important tectonic feature. Part of the mineralized zone is blanketed by up to 70 m of alluvial drift . The remainder is covered by a relatively thin residual soil layer. The mineralized zone, however, was not detected by conventional stream-sediment sampling because pathfinder elements, such as Cu and Mo, have not been geochemically dispersed into the main drainage system. The deposit was discovered by a combination of soil analysis and inspection of rock fragments from small pits.Twenty widely spaced, shallow drill holes have outlined an areaover 2700 m long and 550 to over 1000m wide that grades more than 0.1% copper equivalent (% CuE = % Cu + (5 x % MoS2)). Two smaller zones grading over 0.4% copper equivalent occur within the larger area. The limits of the widest end of the deposit have not been delineated.The Cash deposit is fairly typical of high-level, calc-alkaline porphyry copper-molydenum occurrrences in the Canadian Cordillera {cf, CIM Special Volume 15) and is representative of most prospects in the Dawson Range. It is associated genetically with a subvolcanic complex of small, irregular stocks and dykes of feldspar porphyry and related breccias of Late Cretaceous age. Copper and molybdenum sulphides occur along fractures, in quartz veinlets and disseminated in feldspar porphyry and in older metasedimentary and intrusive rocks. Higher-grade zones of copper and molybdenum have associated potassic alteration. Phyllic alteration is, in part, superimposed on potassic alteration. Argillic alteration occurs locally.This paper describes the history of the discovery and the geochemical and geophysical characteristics, together .with the regional geology, and the nature and distribution of the host rocks, hypogene mineralization and hydrothermal alteration."

Jan 1, 1981

By M. J. Davie, D. S. Ross

"The successful design of a new mine water pumping system is in part dependent upon the accuracy with which the operating conditions can be forecast. This paper outlines the data which should be obtained on water quantity and quality. Methods of modifying the quality are also discussed. Some pumping systems for disposal of sludge are described, citing operating examples. The various types of mine dewatering pumps are described in terms of design characteristics as they affect operating efficiency and installation and maintenance costs. Piping system parameters are outlined. Finally, a hypothetical case study of pumping from a depth of 3,000 ft is assessed, with particular reference to capital costs.IntroductionMany mine operators would agree that the pumping system usually receives a low engineering priority during the design stage, and as a consequence causes some of the most frustrating problems during production. For a ""dry"" mine (up to 200 gpm), design of the pumping system may indeed be simple, but outside of the potash industry such mines are not common. For ""wet"" mines, the pumping system is important because it significantly affects the initial capital and on-going energy costs of the mine and, in the area of sludge disposal, the working conditions and production costs. Indeed, a failure in the pumping system usually has serious, and sometimes disastrous, consequences.The intent of this paper is to outline the factors which should be considered in the design of a pumping system and to describe the types of pumps used in mine dewatering and relate them to practical operating systems."

Jan 1, 1980

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By P. B. Demarsh

"Location: - Mine village of Perron, 11 miles east of Val d’Or in northwestern Quebec.Life; - Started production 1932, ceased 1951.Ore: - Flat lying quartz tourmaline veins within granodiorite. Gold values related to coarse segregations of pyrite. Specific gravity 2. 80.Capacity: - 30 tons 1932-35; 125 tons 1935-37; 350 tons 1937-51.Assay: - Heads 0.21 to 0.34 oz. per ton. Grade obtained by mining 600 tons daily, sorting belt reject 250 tons, balance to milling; tailings loss 0.003 to 0.005 oz. per ton; extraction 9 8. 5%.Grind: - 70% minus 200 mesh. Detention time 26 hours.Treatment: - Cyanidation process.Reagents: - Per ton, aero cyanide (NaCn) 0.36; unslaked lump lime 1.50; zinc 0. 03; lead acetate 0. 006; steel consumption 2. 50.Water: - Equal mixture of swamp creek water and underground seepage.Cost: - Per ton, sorting and crushing 0.21; grinding 0.31; cyanidation 0.11; filtration 0.05; precipitation 0.02; miscellaneous 0.22; total 0.92.Power: - Hydro-electric, 25 cycle, 12, 000 volts reduced to 550 volts.Labour: - 95% Maritime and European, balance Quebec and Ontario.Tailings: - Absorbed over large swampy area on barren mining claims.Personnel: - 1 7 men including supervision.Flow sheet: - Canadian Mining Manual 1947"

Jan 1, 1966

By D. Komljenovic, E. Lafontaine, J. Paraszczak

Availability of the production equipment used in underground mines has a substantial impact on production costs and, thus, on mine profitability. Appropriate collection of pertinent data and information, as well as use of adequate performance measures and their analyses, can help mine operators identify cost-effective opportunities to improve equipment availability. This paper presents study results aimed at reviewing and analyzing means and measures used to quantify equipment availability and its contributing factors (reliability, maintainability and maintenance support) in several Canadian underground mines. It overviews sources, as well as quality and quantity of relevant data and information, and examines performance measures and their definitions, as applied to surveyed mines. Problems concerning data acquisition and meaningfulness of the performance measures are discussed. The paper concludes with some suggestions and recommendations concerning several aspects of equipment availability assessment. Evidence suggests that the latter may become a more useful tool for mine operators in their efforts to reduce production cost.

Jan 1, 2008