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By J. G. Thomson

Development of the Canadian North, a subject of growing national interest, must in part await the development of better forms of trans-port. The estimated 500,000 square miles of muskeg terrain in the north combined with the" scarcity of roads make essential the early development of special purpose muskeg vehicles. Good progress has been made in the last eleven years in classifying muskeg and some progress has been made in determining its mechanical properties. Limited travel is now possible through the use of special purpose tracked vehicles which have been built without adequate design data. A program to provide data which can be used to optimize muskeg vehicle designs began in 1957. The results of the second phase of this pro-gram are presented in this report. It is shown that vehicle performance in muskeg is directly related to the mechanical properties of the muskeg. Further, it is shown that good de-sign practice for tracked vehicles expected to operate in snow, sand, soft clays and loams is also good practice for muskeg vehicles. All indications are that muskeg mechanics is properly a part of conventional soil mechanics.

Jan 1, 1961

By Z. D. Hora

Sand and gravel resources of the southern coastal region of British Columbia may be linked to various episodes of Wisconsin glaciation. During Wisconsin and probably earlier times, the Fraser Lowland and coastal areas were subjected to repeated glaciations separated by non-glacial intervals. Each major glaciation was accompanied by isostatic and eustatic changes in sea level up to 200 m or more. As a result, the Lowland was covered by the sea during much of Quaternary time. Because the Fraser Lowland is surrounded on two sides by high mountain ranges, glaciers terminated in the sea during their maximum advance. Therefore, meltwaters released during deglaciation, together wit h retreating glacier ice, could produce widespread and extensive sand and gravel deposits both along the coast and throughout the Fraser Lowland and adjacent areas.

Jan 1, 1984

By J. J. Baz-Dresch

"The Cannon Mine, a joint venture between Asamera Minerals (the operator) and Breakwater Resources, is located in the centre of Washington state at the eastern base of the Cascade Mountains. The mine complex is located three blocks south of the city limits of Wenatchee, part of an urban area with a total population of 47 000. The closest residence is 350 feet from the mine portal.The B-Neath zone is a narrow, high-grade, downward extension of the southern tail of the mine's main ore body, the B-North zone. It also underlies the northernmost portion of the B-West zone (Fig . I) . The ore is usually reasonably competent but completely surrounded by very weak rock consisting of shear zone and unsilicified sandstones and siltstones.The zone has maximum dimensions of 420 ft in thickness, 500 ft in length , and 200 ft in width . The economic reserves extend from the 70-ft elevation (elevation above sea level) to the 630-ft elevation and consist of about 1.3 million tons of geologic reserves (proven and probable) at an average grade of 0.33 ounces per ton.Acquisition and ExplorationInitial DiscoveryThe initial discovery of the B-Neath zone was made by Tenneco Minerals during July through September, 1984. Their 22-hole surface drilling program consisted of 18 200 ft of drilling. Tenneco Minerals had acquired the 91/2 acre lease from United Mining Corporation.Asamera Minerals subsequently purchased Tenneco's lease in July, 1985; Tenneco retained a royalty position which was later purchased by Echo Bay Mining.Follow-up drilling by Asamera Minerals consisted of both surface and underground drilling. Eight surface holes (7200 ft) were drilled commencing in December, 1985. Following evaluation of the geologic data, an access drift was driven on strike along the top of the ore zone on the 500 level. Diamond drilling from this platform consisted of 17 200 ft in 79 holes."

Jan 1, 1990

By Derek Perkins

"Brenda Mines Ltd. operates an open pit copper and molybdenum mine located in south central British Columbia. The main economic mineralization is chalcopyrite and molybdenite. Pyrite, galena and sphalerite are also present in varying quantities. The mineralization is present in small veins and fractures in a porphyritic quartz diorite host rock.The mill processes approximately 30,000 tonnes of ore daily. The ore is crushed in three stages and then ground in conventional rod mill - ball mill circuits with cyclone classification. The cyclone overflow is fed to the bulk flotation circuit as a pulp with a density of 50% solids. The particle size distribution is approximately 35% plus 65 mesh. Bulk rougher and cleaning flotation produce a concentrate grading approximately 20% copper and 4% molybdenum. This concentrate is fed to the separation circuit, where the copper is depressed with sodium hydrosulphide and the molybdenum is floated. These products are further ground and then upgraded by column flotation. The molybdenum concentrate is pumped to the leach plant to reduce concentration of lead and copper. It is then washed, filtered, dried and packed for shipment to Europe. The copper concentrate is filtered, dried and subsequently shipped to Japan.Prior to November 1977, the mill flotation control was carried out by the assay laboratory using a Philips PW 1540 sequential x-ray spectrograph. The assay set consisted of twelve samples, analysed on a two hourly basis for copper, molybdenum, lead, iron and silica.In order to provide elemental composition information on a much shorter sampling interval and to produce speedier control analysis for automating process control, an Applied Research Laboratories PCXQ on stream analyser was purchased. The installation of this analyser, reduced the turnaround time of the control analyses from (2) hours to (20) minutes. At Brenda, the following assays are used in the mill control strategies."

Jan 1, 1989

By D. M. Morrison

"Microseismic systems at five mines in the Sudbury Basin provide the basic data for Falconbridge Limited's rockburst research. Daily and long-term analysis of this data as well as underground observations has confirmed the fault-slip mechanism of rock bursting at three mines. A detailed analysis of the complete history of Falconbridge Mine is being conducted and Distinct Element numerical models are being used to simulate both the stick-slip behaviour of faults and the dynamic effects of the induced vibrations on rock and backfill. University research includes acoustic tomographic imaging of the rock mass based on seismic wave propagation and collection of full micro seismic waveforms to allow application of advanced seismic and statistical analysis techniques. INTRODUCTIONFalconbridge Limited currently has five mines operating in the Sudbury Basin: East, Lockerby, Onaping, Fraser, and Strathcona Mines, which along with the Falconbridge open pit produced 2.8 million tonnes of ore in 1986. The underground mines range from about 600 m to 2000 m below surface and one of the consequences of mining at these depths is the occurrence of rockbursts.Research into rockburst phenomena at Falconbridge began over 25 years ago and research is continuing in an effort to avoid the problem by improved mine design, to protect mine openings from damage by design of effective support systems and to better understand the processes which precede a major fault slip rockburst. Since the early 1980s, significant progress has been made due principally to micro seismic monitoring and advances in microcomputer technology coupled with detailed underground investigations.It is now possible to identify the fault-slip mechanism as the cause of many of the rockbursts which occur at Falconbridge mines. By gaining an understanding of effect of mining-induced stresses on the pre-existing geological structures, areas which may experience rock bursting can be identified and can be protected against severe damage by appropriate support techniques."

Jan 1, 1989

By Jeffrey T. McGinty, Frank M. Wheeler

Plant layout is the arrangement of equipment, process areas, departments, infrastructure, and support facilities. Plant logistics is the flow of parts, people, resources, and information throughout the production process. This chapter: outlines key factors and provides checklists to facilitate layout development; presents risk management approaches to test the logistics and functionality of alternative layouts; and uses real-world examples to illustrate effective simulation modelling to assess plant layouts.

Jan 1, 2015

By L. P. Chrismas

"IN 1975, Nova Scotia produced 1.8 million tons of coal with a FOB mine value of $47.6 million. Of this total, about 30 per cent or 600,000 tons was coking coal and the remainder was steam and industrial-grade coal. The Nova Scotia Power Corporation consumed 630,000 tons in three generating stations and 570,000 tons were sold to Sydney Steel for making coke for its steel operations. Exports, principally to Great Britain, comprised 370,000 tons in 1975 in addition to the 300,- 000 tons shipped to other provinces for use by cement and pulp and paper companies. In 1975, just over 100,000 tons of coking coal were imported into the province from Alberta. Before 1975, low-volatile coking coal was traditionally obtained from the United States. In 1975, production came from seven individual mines and one project involving reclamation from mine dumps in Pictou County. Of the seven producers, four are owned by the Cape Breton Development Corporation, a federal Crown corporation; the remaining three are small independent mines, but, even though small, they are sizeable contributors to the economies of their local areas. After 101 years of continuous operation, Devco's Princess mine was closed in 1975. The Nova Scotia coal industry, in terms of value, accounted for about half of total mineral production in 1975. The industry provides jobs for 3,000 men and women. It is also significant that in 1975 Nova Scotia produced about 6.5 per cent of Canada's total coal production of 28.3 million tons. Detailed statistics on Nova Scotia's coal industry appear in the Appendix."

Jan 1, 1976

By B. J. Keating

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

Jan 1, 1960

By M. Mohan Rao

A Sievert ' technique was used. The few determinations made on 10 per cent and 20 per cent V alloys did not show any deviations from Sieverts' law up to I>N2 = 1 atmosphere. The same held true for alloys of 0.2 per cent Ti. Nitrogen absorptions in Fe-Ti alloys, containing from 0.50 to 0.77 per cent Ti at 1,600°C, follow Sieverts' law at low PN2 values, but, due to the formation of a delta titanium nitride phase, deviate from this law beyond critical values of PN2? There is evidence that this phase is Ti1.1N. The behavior observed can be described by the followmg equations: Ti,.,N(o) = 1.7Ti + N K = (fT; ? % Ti)1?7 (f;;.? %~_) = 0.0020 K = fN. %~ = 0.042 '\)-:>N 2 I NTRODUCTJON Nitrogen's solubility in liquid iron-vanadium alloys was investi-gated briefly by Brick and Creevy ( 1), and more extensively by Kash-yap and Parlee (2) and by Pahlke and Elliott (7). Nitrogen's solubility in liquid iron-titanium alloys

Jan 1, 1963

By L. X. Li

Coking coal producers often encounter variations in clean coal quality when mining multiseam deposits containing coals with different washability and coking properties. This paper describes how, for a single coal property, an initial clean coal specification with an ash content of 8.5% on an air-dried basis (ADB) and a free swelling index (FSI) of 5.5 can be improved to a specification with 7.5% ash content ADB and an FSI of 6. This is accomplished by sorting coal seams into two groups for processing and blending. A preliminary economic model demonstrates how this improvement enhances economic returns through a beneficial factor.

Jan 1, 2014

By Barry W. Schmitke, J. M. Marino

"Cigar Lake Mining Corporation is presently operating an underground test mine in northern Saskatchewan, with a view to developing a high grade uranium deposit. The mining test is intended to demonstrate that the innovative mining methods designed are safe and economical. Two vertical mining methods are considered for the test:• box hole boring from the lower level;• blind boring from the upper level.In both cases, it is anticipated to freeze the ground before excavation to ensure hole stability and limit the inflow of water. Special care will be taken to minimize radiation exposure of personnel.Remote controlled equipment will be used where applicable.The access to the orebody was an important component of the test. After shaft sinking to a depth of 500 m, development work commenced at the 420 level in fractured sandstone which was grouted to restrict the inflow of formation water. The drifting continued in a section of poorly consolidated sand, clay and sandstone; this area was frozen to allow stabilization prior to excavation. At the 480 level relatively little water was encountered in the altered basement gneiss and grouting was not necessary; however, extensive ground support was required in the soft ground areas."

Jan 1, 1992

By K. Soldenhoff, M. Fainerman-Melnikova

The use of strong base resins for uranium recovery is severely affected by the presence of chloride ions in solution. In areas where high-quality process water is not readily available, the use of saline water would extend the potential application for ion exchange in uranium processing. This study presents measurements of uranium uptake, using a wide range of commercially available weak base anionic exchangers, from solutions with chloride concentrations ranging from 2.5 to 22 g/L Cl. Out of 14 weak base anionic resins tested, 3 were identified that were not severely impacted by the presence of chloride and significantly outperformed a gel strong base resin typically used for uranium recovery in high-chloride environments. The uranium loading was sufficiently high for the consideration of development of the application of uranium recovery from uranium ores leached with seawater.

Jan 1, 2012

By M. Rudolph, T. Leißner, TU Bergakademie Freiberg, C. Mämpel, R. Möckel, M. Embrechts, T. Leistner

Tin-mining activities have taken place in the region of the German Erzgebirge (Ore Mountains) for over hundreds of years up until 1991. For long times, gravity separation processes used to be the dominating beneficiation approach in those mining districts to recover cassiterite, the main tin-bearing mineral. For fine (< 100 µm) and very fine (< 20 µm) particles these approaches might not represent effective techniques, significant valuable materials could not be recovered and reported to tailings, where it was subsequently disposed. Thus, there are substantial amounts of cassiterite still present in these tailings disposals, most of it as very fine particles with already high degrees of liberation. That fact brings these tailings disposals into focus for potential reprocessing using beneficiation approaches, which are more sensitive to fine and very fine particles. In this paper we present results concerning the laboratory-scale treatment of material from exemplary heaps of the former Altenberg and Ehrenfriedersdorf mining sites using various flotation methods (including conventional froth flotation and oil-assisted flotation). Different size ranges of the material were previously prepared in order to investigate their response to the different techniques. For the study, special emphasis is put on agglomeration flotation, an oil-assisted flotation method. Therefore, an aliphatic oil phase of alkane basis is used to either selectively aggregate or collect the cassiterite particles. Recovery and flotation performance results are presented with respect to different process parameters: various collectors (including sulphosuccinamates and phosphonic acids) and depressants (including sodium fluorosilicate and oxalic acid) regime, oil dosage, agitation time and pulp density during oil/pulp agitation. Furthermore, the oil/particle aggregation behavior is analyzed via particle image analysis and, additionally, collector adsorption characteristics are investigated by contact angle measurements and zeta potential analysis. The data obtained is correlated with the testwork results achieved in order to interpret the flotation response of very fine cassiterite particles.

Jan 1, 2016

By A. E. McIlhinney, I. E. Puddington, C. E. Capes, A. F. Sirianni

"Two main problems are associated with the removal of pyritic sulphur from coals. The first is due to the fine state of dissemination of pyrite, which requires grindin1 to a very fine size to accomplish liberation. The second problem is caused by the similar surface chemical characteristics of coal and pyrite, which complicates separatio11 methods based on this property. In the work described here, the problem of fine particle size was overcome by using the selective oil agglomeratioa method developed at the National Research Council of Canada. Recovery of more than 90% of the combustible values was possible, even with particles only a few microns in diameter. Experiments using conventional chemical depressants for pyrite met with little success. It was found, however, that pyrite may be rejected during coal agglomeration through treatment with the iron.oxidizing bacteria, thiobacillus-ferrooxidans. The conditions for maximum pyrite separation are described and possible mechanisms by which the bacteria act are discussed."

Jan 1, 1973

By John E. Callahan

"A stream sediment geochemical survey covering an area of 13.000 sq. km near Churchill Falls. Labrador. was conducted for Brinex (British Newfoundland Explorations Ltd.) prior to partial flooding by the Churchill Falls power project. Stream sediments (minus 80-mesh) were analyzed for Cu, Pb, Zn, Ni, Ag, Mo. U and Mn, and the heavy mineral, nonmagnetic fraction (minus 60-mesh) for Cu, Pb, Zn, Ni, Ag, Mo, Ba and Mn. A binocular examination of the concentrates for sulphides and pyrope garnet was done on the heavy mineral concentrates. The concentrates were also examined for fluorescent minerals.Two distinct areas with high trace-element values indicate the need for follow-up studies. The first is in an area of gabbro erratics containing massive and disseminated sulphides (pyrrhotite, pyrite and minor chalcopyrite) on the western edge of the survey area along the Esker Road. The second, largest area (several hundred square kilometres) is anomalous in U and Mo and associated with felsic intrusives (Red Wine Complex?), syenites. granite gneiss and sedimentary rocks (Seal Lake Group?).The binocular study showed that almost 15% of the heavy mineral concentrates contained pyrite and no other sulphides. This indicates that this technique may be worthwhile in determining the presence of sulphide minerals in stream sediments from glaciated environments. The only fluorescent mineral observed in the study was zircon."

Jan 1, 1981

"INTRODUCTION Secondary mine ventilation has been hamstrung by the availability of fans that satisfy many competing operational factors. The sometimes legislated requirement of adequate volume to the working face, the minimisation of excavation required to fit the selected secondary fan and the power requirements of various operational phases has, in the past, not been satisfied with just one system. The new system being introduced overcomes all these competing requirements in one simple unit with an added bonus of being very durable without loss of performance when wear occurs on the impeller. Existing Operational Situation Several studies (e.g., CIPEC, 2005; LCG Energy Management Group, 2009) have found that between 42% and 49% of mining energy costs are associated with mine ventilation, depending on the type of mine and the equipment used. If we then look at the general breakdown of installed power of the secondary fan to primary vent fans, the ratio is around 2:1. Thus the total energy costs of the secondary ventilation represents about 25% of the overall mining energy costs. It is of interest to note that the cost of running a typical two stage axial vs the cost of purchasing and general maintenance cost of the same fan over a 10 year period, the breakdown will be conservatively in the order of 40:1.The currently available secondary ventilation axial fan have one duty curve at any given time. Generally this can be changed manually within the motor power parameters but requires a minor outage and removal of the fan to do the pitch adjustments. As the bag vent ducts grow longer, the supplied air reduces to a point where inadequate air is supplied to the working face. This is exacerbated by underground equipment putting additional resistance in the heading and further reducing the supplied air at the working face. This shortfall is normally corrected by the installation of an additional fan in the system to overcome losses in the bag system but comes at a cost of production as the heading needs to be shutdown to install the second fan. This also means that the heading is supplied with excessive air on the shorter runs with a wastage of fan power."

Jan 1, 2019

By A. Bouchard

"Based on laboratory testwork, a two-stage cleaner / re-cleaner circuit with feed regrind was proposed to replace an existing single-stage middling circuit treating a scavenger concentrate at Inco’s Clarabelle mill. In order to effectively transfer the technology and implement the new flowsheet in the plant, an extensive on-site pilot plant campaign was conducted. After demonstrating the improved metallurgy, the two-stage middlings circuit was successfully implemented at the operation.The present paper describes the on-site pilot plant testwork and the plant metallurgical improvement after implementation of the new middlings circuit. The addition of TETA / Na2S03 greatly enhanced the pentlandite selectivity against pyrrhotite and the two-stage cleaning considerably improved the pentlandite selectivity against rock minerals. The improvement was immediate after the installation of the new middlings circuit. Size by size recovery analysis indicated that a finer regrind would further improve the metallurgy of the new two-stage cleanerhe-cleaner circuit and those modifications are in progress at the mill.INTRODUCTIONThe milling operation at Inco’s Clarabelle mill has been described elsewhere (Kerr and Kipkie, 1985; Agar, 1991). While maximizing the recoveries of chalcopyrite (Cp) and pentlandite (Pn), continuous effort has been directed toward improving pyrrhotite (Po) and rock minerals (Rk) rejection. Inco discovered diethylene triamine (DETA) and triethylene triamine (TETA) (Marticorena, et al., 1994) for pyrrhotite rejection. Falconbridge further improved pyrrhotite rejection using DETA and SO2 (Kelebek, et al., 1995). No special technologies are used in the rejection of rock minerals."

Jan 1, 2001

By D. Bouchard, M. Forté, A. Charette

A transparent replica of a casting die was built to achieve a better understanding of the filling mechanisms of aluminum in high pressure die casting. Water and tomato paste were respectively used as analogues for the Newtonian liquid aluminum and the non-Newtonian semi-solid aluminum. The transparent die was installed on an industrial casting press and filling was filmed with a high-speed camera. Differences between the Newtonian and non-Newtonian fluids are presented and discussed.

Jan 1, 2006

"The Hardy Cross algorithm offers a reliable method of solving network systems of fluid flow and has become widely used for solving water and ventilation flow networks. A limitation is that computational iterations and time to solve a network rises rapidly with the size of the model and modern detailed ventilation networks have typically grown to thousands of airways. Non-linear matrix solving methods can offer improved performance, however these are more complex and may be unstable if initial estimates are poor. This paper presents improvements that can be applied to the traditional Hardy Cross algorithm to greatly reduce iterations and solving time for large ventilation models. INTRODUCTION The Hardy Cross algorithm (Cross, 1936), was originally developed to solve water flow in city and urban pipe networks. Using principles of Kirchhoff’s electricity current laws, Hardy Cross developed an iterative algorithm for solving non-linear equations associated with network water flow. Traditional network analysis research refers to the various members of system networks as branches, nodes and meshes. This terminology has been changed in this paper to airways, junctions and loops respectively which are terms more familiar to engineers in mine ventilation. When Kirchhoff’s laws are applied to fluid networks, the following assumptions can be made: •The sum of fluid flows into a junction must equal the sum of fluid flows out of the junction.•The sum of pressure losses around any loop through a network system must be equal to zero.An iterative solution can therefore be achieved by initially guessing flow in a network, calculatingthe pressure losses around the network loops (Figure 1), and applying flow corrections using Newton’s method for each loop if the sum of the pressure losses does not equal zero. To solve the system, a loop must be defined for every segment or series of segments between a junction of 3 or more airways.The Hardy Cross algorithm has been used extensively for ventilation network analysis since the introduction of the first electronic computers (Tien, 1997), however numerous other variations and methods have since been developed through the use of matrices to solve the required system of nonlinear equations. Commonly used algorithms such as the Newton Raphson method (Brown, 1969), the Gradient method (Todini & Pilati, 1988), the Linear Theory method (Gupta & Prasad, 2000), and Coupled Network Solver (G. Danko, 2008) have found general use in fluid flow network solvers (Rossman, 2000). Despite poor and sometimes unpredictable convergence performance however, the Hardy Cross algorithm still has unique properties that make it attractive for ventilation models. Some benefits are:"

Jan 1, 2019

By V. K. Karra

A mathematical model for the performance of a vibrating screen is developed in terms of an oversize partition curve. This is a normalized curve for any assemblage of particles presented for screening when their size is normalized with respect to the 50 per cent passing size (d50 ) under the prevailing screening conditions. Based on the throughfall aperture (hT) of the wire mesh on the deck, the effects of oversize (% >hT), half-size under (% <0.5 hT), deck location and feed rate were evaluated using the existing screen sizing information. All these variables and also the near-mesh (1.25 hTx 0.75 hT) content (%) of the feed affect the d50. Performance data from different decks of a double-deck screen with various feed rates, size distributions and screen apertures were used to evaluate the near-mesh factor. Effects of wet screening and material bulk density are also incorporated in the model. This generalized model is useful for the simulation of a multiple-deck screen. It furnishes the sieve analysis information of all the deck output streams and therefore has a potential use in the over-all circuit evaluation when used in conjunction with relevant crushing and grinding performance models. An example illustrating the prediction capabilities of the model is given.

Jan 1, 1979