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By W. H. Hastings

Introductory In the amount of her coal reserves, Saskatchewan ranks third among the provinces of the Dominion, with a total, as estimated by D. B. Dowling, of 59,812,000,000 tons. All the coal so far discovered in the Province is lignite, and it would appear unlikely that bituminous or higher grade coals exist. General Occurrence of the Coal The location of the coal-bearing formations in Saskatchewan is shown on the accompanying map. It will be seen that the areas lie principally in the southern part of the Province. The more darkly shaded areas indicate locations where development is taking place, or where coal-seams are known to occur, either through outcrops in valley-sides or through having been encountered during boring operations. The coal-seams are not necessarily continuous throughout the shaded areas, but in all pans of these there are coal possibilities. It is quite possible that small outliers of the coal-bearing formations may occur further north in the Province, but, generally speaking, coal is not likely to be found outside the shaded areas.

Jan 1, 1929

By B. H. Good

This paper describes the research that has been conducted -in an effort to understand the nature and causes of sulphide fires -in the Sullivan Mine. Results of the investigation have led to several theories of the origin: of the fires, the nature of the chemistry and a method for assessing: the fire potential. Recommendations and the implications for the mining operation are also discussed.

Jan 1, 1977

By J. M. Janssens, Van Quach Tinh, M. Ruel, R. Leblanc

"Microscopic studies of peat moss indicate a highly porous material. In view of using this natural product as an adsorbing agent for the treatment of polluted water, studies of its adsorbing power for beef extract and alkyl benzene sulphonate solution were determined. The effects of time of contact, particle size, concentration of adsorbent and concentration of pollutant were studied. In the case of beef extract, there is a COD reduction of around 27 per cent; in the case of the alkyl benzene sulphonate, the percentage reduction varied from 72 to 95 per cent. A water treatment plant based on the adsorbing power of peat moss with simultaneous recuperation of the pollutant is proposed."

Jan 1, 1971

This paper deals mainly with the modernization in the coal loading system at the loading piers of the Dominion Coal Company, Ltd., Sydney, Nova Scotia. The history of the operation is briefly outlined, and the construction of the Company's new pier is described in considerable de-tail. Particular attention is paid to the bins and conveyors, and to the loading tower. The paper concludes with a description of the S.S. Cape Breton Miner, built specifically for the coal trade, and the unloading facilities at Lakeview, Ontario. Coal Shipping at Sydney C OAL from the mines operated in Cape Breton by the Dominion Coal Company, Limited, has been shipped from the International Piers, situated on the east side of Sydney Harbour, for over sixty years. There were three piers, of which two were active-ly used in the shipping of coal until 1964. Nos. 2 and 3 were high piers about 600 feet long, of wooden construction throughout. They were founded on' rock-filled cribs and creosoted piles driven into the harbour bottom, and each had two decks which carried standard-gauge railway tracks.

Jan 1, 1965

By Haruka Takeura, Tomoaki Murata, Kazunari Yoshida, Masato Adachi

"Pure magnesium is a material with high functionality, however, the cold drawing of this material is very difficult, that is why, until this day there are no optimal cold drawing conditions. Furthermore, cold drawing of pure magnesium wire shows a problem with internal defects that occurs under certain conditions. In this research, the aim is the suppression of internal defects, and final target is to create the optimal cold drawing conditions for pure magnesium wires. The first step is the investigation of the drawing limit by using 250°Cannealed wire. As a result, reduction of 10% per pass was chosen for stable wire drawing. However, in this case, it was found that internal defects occurred at total reduction of over 45% during drawing. Investigation of intermediate annealing conditions that can suppress internal defects, and influence on internal defect that the die half angle and reduction per pass. As a result, it was found that the drawing condition capable of suppressing internal defects most efficiently was 13% reduction drawing by using under 6°half angle die. Consequently, it’s possible to manufacture a cold fine drawn pure magnesium wire of 100µm, without defects in the center of the wire and hindering its mechanical properties.INTRODUCTIONMagnesium is a light and high functionality material that has high vibration absorbency, heat dissipation, electromagnetic wave-shielding and recycling efficiency (Conruy, 1989). However, proper cold wire drawing conditions haven’t been established, that is why warm or hot processing is commonly used (Oishi, Mori, &Kawabe, 2005). As a result, strength improvement of the wires is not possible, that is why the production of medical tools is disregarded. If it was possible to cold draw magnesium wires, the applications for material products would expand. Further, in wire drawing such difficult processing material, if appropriate processing conditions are not selected, defects will be generated inside the drawn wire."

Jan 1, 2017

By Diego L. Romero, Joy P. Romero

"IntroductionMinerals may be classed broadly as ferromagnetic (magnetite for example), as paramagnetic (attracts to regions of magnetic field convergence) and as diamagnetic (attracts to regions of magnetic field divergence). High-intensity separators are not necessary to separate ferromagnetic minerals from other classes. Rather, low-intensity units that generate fields below 5000 gauss are adequate for this purpose. However, paramagnetic minerals, such as ilmenite, with high magnetic ""attractability"" require fields of up to 10 000 gauss; those with low attractability may require even higher fields. Table 1 shows approximate ranges of field intensities necessary to separate ferromagnetic and paramagnetic minerals from minerals of lower attractability, along with the force with which they are attracted relative to iron in a standardized magnetic field.Uniform magnetic fields, not useful for separators, are generated between flat parallel surfaces; non-uniform fields, useful for separators, arise when at least one of the surfaces is of irregular shape. The diagrams below show how magnetic lines of force align relative to north and south poles.If a particle is placed in a uniform field, it feels no displacing force unless the particle distorts the applied field assymmetrically. This is not the case in non-uniform fields which are required for magnetic separators.Magnetic fields can be generated by permanent magnets (low intensity), by electromagnets (medium and high intensity) and even by superconducting coils (100 000 gauss fields and higher), although the latter are not as yet useful in production environments .The magnetic force of attraction per unit of mass, that acts on a paramagnetic mineral such as hematite, increases in proportion to the strength of the field . Unfortunately, the highest fields attainable with electromagnets is of the order of 20 000 gauss. Fortunately, the gradient of the fie ld (that is, the degree of convergence of magnetic lines of force) is important, because the attractive force per unit mass is proportional to it also . This can be stated:"

Jan 1, 1989

By D. MacGREGOR, VERA TUREK

The Badgeley Island quartzite deposir in Georgian Bay is worked by lndusmin Limired and was developed in 1969 to produce a high-qualiry silica for use in rhe ferrosilicon and glass industries. The quartzire is part of the Precambrian Bar River Formarion, and is a generally whire, fine-grained rock containing rhin sericire seams. Primary sedimenrary features wirhin the deposit are bedding and ripple marks. Amphibolite and diabase dykes cur the quarr zire body.

Jan 1, 1984

By P. Hr?enjak

Two groups of methods are usually used in design procedures of underground excavation of dimension stone: the analytical and numerical methods of analysis. In all of these methods the in situ rock mass strength represents the main problem. This is due to massive rocks in dimension stone deposits, consisting of large blocks of rock separated with particular discontinuities, for which the Hoek-Brown empirical criterion, developed for jointed rock masses, cannot be realistically used to estimate rock mass strength, especially for a particular block of rock mass or a particular pillar. On the basis of the regular underground excavation process of dimension stone by separating blocks with the flat jack application, we developed the in situ flexural strength testing method. We carried out numerical analyses and evaluation of uncertainty of measurement in order to validate the in situ flexural strength testing method. On the basis of very good validation results, as well as results of the in situ flexural strength testing of exploitable layers on the ?Kanfanar? quarry, we introduced a new coefficient of reduction, which can be used for correction of other strength parameters determined by laboratory testing for obtaining a realistic value of rock mass strength.

Aug 1, 2013

By C. Groccia

As the search for new ore bodies drives mines to be developed at greater depths, the associated high stress environments present challenges for rock support design. Excavations in highly stressed brittle rock are often subject to large volume increases due to rock failure, a phenomenon known as rock mass bulking, which can result in significant wall convergence. Support systems need to be designed to minimize the amount of bulking and to accommodate large wall convergences. In order to design such a support system, empirical guidelines are often used to predict the amount of bulking. However, the empirical guidelines that are currently available are based on a limited number of case studies and consider few input parameters, which may result in an inaccurate bulking assessment. This paper describes methods of collecting quantitative field data at Creighton mine in Canada to better understand rock mass bulking and to further develop the empirical guidelines for bulking assessment for tunnels in highly stressed grounds. Measuring

Aug 1, 2013

By G. Reuben Yourt

THIS paper is chiefly a description of the improvements in dust control chat have been brought about in the assay office grinding room at Wright-Hargreaves. The fume exhaust systems are briefly included because they also are important to the health of the employees. There are three chief factors which determine the efficiency of a dust control system: First, the amount of time and thought spent in designing it. Second, how close! y it is kept up to date with the growth of the plant-a system that is adequate for the number of machines operating when it is installed may fall short of fulfilling its purpose as the plant expands. Third, unless someone is held directly responsible, a system is likely to get out of repair and gradually lose its efficiency-this can easily be detected by regular dust surveys. In designing the present system at Wright-Hargreaves, the object kept in mind was to reduce the dust concentration of all operations to a safe limit, chat is, well under 300 particles per cubic centimecer of air. By doing this, a condition would be attained chat would make it possible to discontinue the use of respirators, which at best are not very comfortable and do not remove all of the hazardous fine-dust particles.

Jan 1, 1941

By Walter Valery, Sergio Vicuna, Roberto Valle, Hamer Arevalo, Ben Burger, Lui Vargas, Alex Jankovic, Jim Seidel, Eduardo Nozawa

This paper describes the design, the first three years of operation and optimization of a large, single stage SAG mill at Minera Yanacocha’s Gold Mill facility located in northern Peru. The Gold Mill was commissioned in March 2008 with a 32’ x 32’ EGL, 16.5MW single stage SAG mill, to process 5 million tonnes per annum high grade oxide Au/Ag ore. Operational control, feed size distribution, grinding media, mill liner, grate and pulp lifter optimisation have allowed the mill to operate 15-30% above design throughput rates, but with a product P80 coarser than design. As part of the optimization, full grinding circuit surveys were conducted. Historical operating data and survey data were analyzed and used to evaluate possible circuit changes and determine alternative operating strategies. A number of changes were implemented which allowed the SAG mill to operate similarly to a large ball mill and achieve finer mill product that was closer to design. This paper summarizes life to date data analysis and improvements made by Minera Yanacocha as well as the grinding circuit optimisation study conducted by Metso Process Technology and Innovation.

Jan 1, 2012

By J. F. Henderson

Stable mining operations commenced in the Northwest Territories in 1933. Pitchblende from Great Bear lake and gold from the Yellowknife district are the main minerals produced. The value of pitchblende products produced from 1933 to 1941 was nearly $6; 000; 000; data on subsequent production are not available. The first gold was produced from the Con mine at Yellowknife in 1938. Other properties that later came into production include the Negus; Slave Lake; Thompson Lundmark; and Ptarmigan mines. The annual gold production reached $3; 862; 000 in 1942 but due to the war and consequent labour shortage fell to $333; 218 in 1945. The only producing mines at present (May; 1947) are the Con and Negus; but several promising properties are under development; including that of Giant Yellowknife Gold Mines where large tonnages of ore are being blocked out. With the reopening of former producing mines and new production from properties now being developed; gold production should rapidly increase and exceed its former peak within the next few years.

Jan 1, 1954

By George Hope, Brigitte Lacouture

"The Red Dog mine has increased mill throughput most years since start-up. Although flotation equipment has been added over the last 10 years, the Red Dog metallurgical performance has been restricted by a lack of adequate flotation capacity. Two reduced tonnage trials conducted in 1997 as well as numerous SAG relines have consistently indicated the potential to significantly increase both zinc concentrate recovery and grade with additional flotation capacity. Later in 1999, a new circuit was designed with increased flotation capacity while simplifying the current circuit, providing for three stages of dilution cleaning, and creating a retreat section. The purpose of the retreat section is to target the more complex particles and allow the chemical environment to be fine tuned for improved iron depression. In total, 21 Outokumpu OK50 (50 m3) mechanical flotation cells and four 3.66 mØ column cells were added to the current flotation circuit. The VIP (value improvement program) mill optimization project is also addressing thickening, water treatment, and power generation issues and has a total budget of US$105 M. Start-up of equipment was phased in to minimize the impact on current operations and the project was completed by the end of 2001. IntroductionRed Dog Operations started production in November 1989. The mine is located above the Arctic Circle in northwest Alaska. It is linked by an 80 km road to a port-site facility where the concentrate is stored. Concentrate is shipped to markets throughout the world during the one hundred days of open seas. As of January 2002, the Red Dog main pit had 38.4 Mt of reserves grading 19.2% Zn, 5.3% Pb, and 102 g/t Ag. Additional reserves and resources contribute an additional 72 Mt at 15.6% Zn, 4.2% Pb, and 78 g/t Ag. Red Dog is a Mississippian to Permian, black shale-hosted, zinc-lead-silver deposit located in the DeLong Mountains, western Brooks Range, Alaska. All the rocks associated with the mineralizing event are considered to be part of the exhalite rock package. Silicification was a dominant component of the mineralizing event and the host shale has been silicified and locally resembles a chert. The major sulphides in decreasing order of abundance are sphalerite, pyrite, marcasite and galena. Most of the deposit’s silver occurs within the crystal structure of the galena. The dominant ore mineral, sphalerite, is very fine grained to amorphous and is commonly intergrown with silica. Ore textures are massive, fragmental, chaotic, veined and rarely show classic sulphide sedimentary layering. The upper portion of the orebody has been physically and chemically weathered. Oxidation has altered the sulphides to sulphates. The zinc and iron sulphates are very soluble and are readily depleted from the weathered cap, while the lead sulphate is residual and is, therefore, enriched."

Jan 1, 2003

By C. Juers

Laboratory chromate coating was applied on AM50 and AZ91D alloys and compared to phosphate-permanganate one. Evaluation of the corrosion behaviour was performed using electrochemical DC and AC methods in ASTM water D1384-87. This electrolyte was chosen because it was moderately aggressive and found to give generally good correlations with long period exposure results in atmospheric conditions. Electrochemical impedance spectroscopy was used to determine more accurately the corrosion rates from the analyses of the high frequency capacitive loop. Anodic polarization was applied in order to evaluate the pitting resistance of the different coatings. These results were correlated with weight loss data evaluated from experiments performed by immersion tests in ASTM water D1384-87 and climatic cyclic chamber tests.

Jan 1, 2006

By Y. X. Li, L. R. Xiao, S. Gong, S. S. He

Porous copper and porous copper based alloys with controllable pore structure have been manufactured successfully by sintering evaporation process. This process consisted of mixing copper or copper based alloys with NaCl powders, hot pressing and final high-temperature sintering to evaporate the filler material of NaCl powders. NaCl was eliminated completely during vacuum sintering, and strong metallurgical bonding in the walls was achieved. The pores’ structural parameter (pore size, shape, and direction) and porosity can be controlled effectively. These porous copper and porous copper based alloys with controllable pore structure have great potential in many fields. Including heat dissipating materials, heat absorbing materials, chemical catalyst carriers, electromagnetic shielding materials, filtering materials, damping materials, silencing materials, battery electrode materials. INTRODUCTION The development of porous materials began in the 1960s. The research of activated carbon with high specific surface area made porous materials enter the stage of material research (Belyakov et al., 2008; Ferey et al., 2008). With the rapid development of science and technology, porous materials play an important role in material research, and gradually become an indispensable part of the material research field (Wu et al., 2012). The research of porous materials has gradually extended to metal, ceramics, plastics and glass and other fields. It has been successfully applied in many fields, such as functional materials, industrial production, aviation, medical materials, biochemistry and electronics, which fully shows that porous materials have considerable development prospects. Porous silicon, plastic porous materials and glass porous materials are the most widely used in the field of non-metallic porous materials (Capelle et al., 2012). Compared with non-metallic porous materials, metal porous materials have developed rapidly in the late 1980s and become new materials with good mechanical properties and excellent physical properties. Porous metal materials have many advantages, such as large specific surface, small specific gravity, good silencing effect, high stiffness, high electromagnetic shielding performance, good shock absorption performance, etc (Li et al., 1999; Ferey et al., 2008). Among its many applications, metal porous materials can be used as both functional materials and structural materials. In some cases, metal porous materials have dual functions and structures. It is a multi-purpose engineering material with excellent performance. At present, porous copper, porous aluminium and porous nickel are the most concerned materials (Chen et al., 2002; Yang et al., 2017; Liu et al., 2018). The preparation methods of porous copper and copper-based alloys mainly include self-propagating high temperature synthesis (SHS), capsule-free hot isostatic pressing (CF-HIP), spark plasma sintering (SPS) (Kvanin et al., 2008; Takahashi et al., 2008; Zhang et al., 2014). However, these methods can not accurately control pore structure parameters (including pore size, shape, orientation, distribution, etc.). In porous materials, pore structure plays an important role in the overall performance of materials. In order to control pore structure parameters accurately and optimize material performance, it is necessary to explore and develop new preparation technology. In this paper, the sintering evaporation process (SEP) was introduced for the preparation of porous copper and copper-based alloys. The core process of the preparation method is hot pressing and evaporative desalination. Hot pressing can make the pore orientation consistent. Evaporative desalination can ensure the complete removal of NaCl in the form of vapor in a short time, thus eliminating the corrosion of residual NaCl on the matrix metal (Gong et al., 2011).

Jan 1, 2019

By R. K. Carnochan

MANY improvements have been made in recent years in the milling of industrial minerals and it is the purpose of this paper to review some of the more important innovations that are now being used in the preparation of these products. Some of the observations which will be made have been prompted by what was seen on a recent trip to industrial mineral milling plants in the north and central sections of the eastern United States. The flotation plants visited were those of the Valley Forge Cement Company at West Conshohocken, Pa., the International Agricultural Corporation at Mount Pleasant, Tenn., and the Aluminum Ore Company at Rosiclare, Ill. Besides these, sand plants in Pennsylvania, West Virginia, and Ohio, coal-cleaning plants in Pennsylvania, pyrophyllite, mica, feldspar, clay, and kyanite plants in North Carolina, and a zinc mill and the Tennessee Valley Authority ceramic laboratory in Tennessee were visited. The milling of industrial minerals can be considered under three broad headings, namely, crushing, grinding, and purification. Usually there is both a separation and grinding problem in treating an industrial mineral, but the problems are distinct, although sometimes a separation is made while grinding, as in the case of a Raymond throw-out mill, which grinds and at the same time throws out most of any hard material present in its feed.

Jan 1, 1939

By Andrew Kerr

Abstract - The base-metal and PGE contents of samples from magmatic sulfide mineralization are commonly correlated with their sulfide contents, indicating that the metal contents of bulk sulfides remain approximately constant within a given prospect or part thereof. Calculated sulfide metal contents provide valuable information in mineral exploration and research, but there are few formal descriptions and analyses of the procedures. Sulfide metal contents are best calculated using an assumed value (35.7% S) for a typical pyrrhotite-chalcopyrite-pentlandite mixture, and there appears to be little advantage in accounting for sulfide species separately. Regression of metal data against sulfur is probably the most rigorous approach, but is not always practical. Above 10% S, calculations are very robust, but lower sulfide contents generally demand at least some correction for non-sulfidehosted metals. Such corrections can become significant below 5% S, and/or in olivine-rich samples. They are best accomplished by mass-balance calculations, using concentration data from unmineralized host rocks. Significant uncertainties are introduced by analytical errors for sulfur, base-metals, and PGE, which are commonly measured from separate sample aliquots. These combined errors in sulfide metal contents generally exceed ±10%, but expand further at low S contents. In general, treatment of data from samples containing <2.5% S must be approached with caution, especially for PGE, for which the exact host minerals may not be known. Application of the method in simple grade-potential assessment is straightforward, but research studies involving sulfide-poor samples are inherently more complex. Under-correction or over-correction of data for non-sulfide-hosted metals can lead to false negative or positive correlations between sulfide metal contents and sulfide content. As the latter may itself be linked to geological parameters, such as depth within an intrusive body, undue significance could be ascribed to such trends. There are also valid geological reasons for such correlations, and such data require careful assessment to separate true and artificial variations. Propagated analytical uncertainties increase significantly in sulfide-poor samples, and must also be borne in mind whenever data from different localities or units are compared and contrasted.

Jan 1, 2001

By P. V. Golde, R. A. Poole, G. R. Baiden

"The results being presented in this paper are those obtained during 1996 on a drilling automation project at Stobie mine. This project has successfully demonstrated that the remote operation of multiple drills (by a single driller) from surface using Tamrock Data Solo 1000 Sixty drillrigs is technically feasible and can potentially bring significant rewards in terms of productivity and work environment improvements, as well as labour and maintenance savings. BackgroundThe ObjectiveThis paper is an update of a previous report on remote drilling research at Stobie mine. Enabled by the communications system installed at the mine, the ability to remotely control underground equipment from surface has been demonstrated (Poole et al., 1996). This paper discusses the needs and process required to carry this concept to consolidate the operation of multiple machines under a single operator.The TeamThe team assembled to develop and implement the automation and the communi-cations extensions needed to allow the multiple machines’ operation from the surface by one operator included the following:INCO Mines Research supplied the project management and original project initiative. The primary purpose was to prove the advantages of savings associated with the driller not being required to travel to the underground drill location coupled with the savings associated with one-man, multiple-machine techniques.Tamrock EJC supplied the Data Solo 1000 Sixty drills and the Tamrock specific machine-based custom software. The drills were produced in Finland with no provision for remote operation of the drill from other than the umbilical attached local console.Automated Mining Systems supplied the modifications to the drill communications equipment to allow the machine communications to become broadband compatible. As well, Automated Mining Systems also supplied the hardware necessary to be able to remotely control the portable video camera, as well as the data logging equipment.Stobie Mine personnel were made available to test the function and then integrate the concept of remote control drilling into the Stobie operations."

Jan 1, 1997

By R. Vracar, D. Sinadinovic, Ž. Kamberovic

The paper presents a study on the oxidation of polymetallic gold ore by oxygen in an autoclave. It presents optimum parameters of autoclave leaching of sulphide refractory ore in self-generated sulphuric acid solutions aiming to get products with favourable technological characteristics from which precious and other useful metals can be recovered. A high partial oxygen pressure (1.5 MPa to 2 MPa), high leaching temperature (190°C to 200°C), pulp density 80 g/L to 240 g/L, ore fraction size 76 µm and leaching time up to 4 hours yield good results in rich ores. The full extent of copper and zinc conversion as well as a high extent of iron conversion has been achieved, while lead, gold and silver and a minor part of iron remain as a solid residue among gangue minerals.

Jan 1, 2001

By S. Kapusniak

Specialist Machine Developments (SMD) is a design and manufacturing company involved in the design of Remotely Operated Vehicles (ROV?s), ploughs, trenchers and mining machines for use in submerged environments. Established in 1971, the company has made over 500 vehicles for subsea use. These range in size from small remotely operated swimming vehicles with a weight of less than a tonne to heavy duty seabed crawling machines with a weight of up to 310 tonnes (in air). Primarily, these machines have been designed for offshore vessel-based applications, but the machines are equally suited to other submerged mining applications onshore. Many onshore deposits can technically and theoretically be mined using currently available submerged mining ROV technology. Similar equipment to that in use subsea could easily be fast-tracked into use to extend the life of opencast mines facing severe hydrological problems. It could also easily be used to mine vertical ore-bodies where the stripping ratio has become uneconomical due to increasing depth. In some cases mining ROVs could even be suitable for use as the primary extraction method for a new mine. Exploration and extraction techniques used in oil and gas gradually developed and moved from land to offshore in the middle of the last century. Are we about to witness a similar shift with other minerals? This paper describes the design concepts of submerged mining equipment, targetted subsea mineral deposits, the suitability of submerged mining ROVs for onshore deposits, limits to their application and parallel research and development activities which will help to accelerate the use of such equipment in the emerging submerged mining sector.

Aug 1, 2013