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By Xiaozhu Chen, Qi Ping, Pu Yuan, Qinyong Ma

"In order to investigate the fractal feature of coalmine deep rock fragments under impact loads, variable cross-section split Hopkinson pressure bar apparatus, 50 mm in diameter, was adopted to conduct impact compressive test for rock specimens from -962m deep coalmine. Various impact pressures, such as 0.3, 0.6, 0.9 and 1.2MPa, were selected to implement different loading rates. Sieving statistical analyses were conducted for rock fragments after being impacted, and the particle size distribution of broken rock in various loading rates were calculated with the fractal method and then the corresponding fractal dimension was obtained. Test results shows that there is a good self-similarity and fractal feature in fragments distribution of deep coalmine sandstone under impact loads. The fractal dimension of fragments is between 1.9 and 2.7. The research also indicates that there is an approximate power relationship between dynamic compressive strength and fractal dimension, and a strength power relationship between fractal dimension and average strain rate. Moreover, there is a linear relationship between fractal dimension and specimen absorbed energy. The rock fractured process can be quantitatively described through fractal dimension, which can reflect the deep rock broken degree and is an ideal index to evaluate the distribution of rock fragments.INTRODUCTIONBroken rock is one of the most basic processes in mining operations, rock fragmentation has always been an important index to evaluate rock breaking effect (Xu & Yu, 1984). Macroscopic fragmentation of rock material is the final results of continuous development, expansion, gathering and cutthrough of internal micro-cracks. This process, developing from microscopic damage to macroscopic fragmentation, is an energy dissipation process and shows fractal characteristics (Xie, 1993). Turcotte (1986) has conducted statistical analyses of fragmentation for different kinds of geological materials under various broken conditions, and arrived at the conclusion that fragmentation distribution is a fractal."

Jan 1, 2015

By DONALD E. BARNETT

Since the days of early settlement ew Brunswick has produced a variety of industrial minerals but it is perhaps only the recent discoveries of significant reserves of potash that have elevated the meaning of industrial minerals in their contribution to the provincial economy. With potash production commencing in July 1983, the role of industrial minerals will increase significantly to the value of mineral production in the province.

Jan 1, 1984

By Han Xing, Cui Jianzhong, Qin Ke, Shao Bo, Zhang Haitao

In this paper, a new approach that uses hot-top DC casting process to producing multi-alloy ingots is present. The different type and size of composite and coated ingots (4045/3004/4045 three-layer composite ingots with section 630mm by 1500mm and 4045/3003 coasted ingot with F140mm/F110mm in diameter) are cast by this approach. The macro-morphologies and microstructures of the composite ingots, the temperature distribution and the element distribution in the interface zone were investigated, also and the interface bonding strength was measured. Results show that the solid supporting layer formed on the cooling plates plays a key role in the casting process of composite ingots. The solid supporting layer can prevent the blending of two melts by resisting the impact of alloy melt, which ensures the stable casting process and casting high quality composite ingots, because the contact height is increased using hot-top DC casting. In addition, fabrication and properties of 4045/3004/4045 three-layer composite ingots with section 630mm by 1500mm are reported in detail.

Jan 1, 2015

By Zihe Ren, Edouard Asselin, Marcus Tomlinson, Tianbi Zhang, Jing Liu

"Raman spectroscopy is used to quantify the extent of disorder in the carbonaceous matter associated with preg-robbing ores. Previous studies of Goldstrike ores showed that the height and width of the peaks for the “D” (disordered) and “G” (graphite) bands, the so-called “Raman ratio” had a strong correlation to the preg-robbing value (PRV) measured for various ore samples. A brief literature review on Raman spectroscopy as it applies to preg-robbing ores is presented. Further, recent studies, presented here, have shown no correlation between the Raman ratio and the PRV for a wide variety of ores. This suggests that the extent of organic carbon crystal disorder is not the main factor in determining preg-robbing characteristics.INTRODUCTION Valuable base metals, such as nickel, cobalt, molybdenum, vanadium and tungsten, are used in a wide range of important technological applications. The demand for many of these metals has increased significantly over the last few decades, driven especially by economic expansion in Asia generally and China in particular. This has led in turn to a large growth in the output of mines in order to satisfy this increasing demand, as shown by the data in Table 1 (USGS, 1994, 2014). These data reflect an even longer trend of growth of these metals, with nickel, for example, showing an average rate of 5.3% per year from 1980 until 2015 (International Nickel Study Group, 2017). This rapid and sustained rate of growth means that annual mine outputs for nickel, tungsten, molybdenum and vanadium have had to double roughly every 11 to 14 years, whilst cobalt mine output has had to double roughly every 7 years, over the period from 1994 until 2014. With the average working life of a nickel mine being between 17 and 22 years (Statista, 2017), this means that from the time a nickel mine opens until it closes, the industry needs to find the equivalent of another three or four mines of a similar output to satisfy this relentless growth in demand for the metal."

Jan 1, 2017

By W. T. Robson

ONE of the problems encountered in any mine is the effect of increasing pressure manifested by increasing depth. Although the depth at which excessive pressure assumes serious proportion, and the manner in which it appears in underground workings, are influenced by a variety of factors, nevertheless the difficulty is present in all mines and its gravity increases with increasing depth. In the Kirkland Lake camp, as far back as seven years ago, mining had proceeded to depths sufficient to result in the formation of pressure great enough to cause violent disruption of masses of rock. It is proposed in this paper to deal with the effect of pressure caused by mining as observed at Lake Shore Mines, and to describe some of the methods which have been adopted to counteract it. There are many contributing factors in a study of the problem, and results vary widely in individual mines and in different localities. One feature common to all, however, is that there is ground subsidence, evidenced either by a gradual settling accompanied by crushing and shearing of the ore and wall-rocks, or the disruption of the ground surrounding the periphery of an excavation may take place suddenly, attended by more or less violent shattering of the rocks. Such violent failure of a mass of rock has been designated by the term rock-burst. The history of rock-bursts extends over a great number of years. They have occurred in some form or other in practically ali places where mining operations, at all but very shallow depths, have been carried out. Since the theoretical aspects of the subject have been dealt 'with at great length by capable and experienced writers (1), the present paper will give only a brief résumé of the theories propounded by those engaged in deep mining operations in various parts of the world.

Jan 1, 1940

By A. S. H. Kabir

Due to the high specific strength and excellent corrosion resistance, Ti-6A1-4V has been widely applied in aerospace industries. In this study, the welding performance of 3.2-mm and 5.1-mm thick Ti¬6A1-4V sheets was studied using a 4 kW continuous wave Nd: YAG laser. It is found that the use of filler wire, matching the parent metal composition, can bridge the joint gap and produce full penetrated welds up to a width of 0.6 mm without cracking. The laser welds were characterized in terms of the bead geometry, defects, microstructures, and hardness. With increasing joint gap, the percent porosity area increased, reaching just over 1% of the fusion zone area at a gap width of 0.6 mm for the 3.2 mm and 5.1 mm thick sheets. The maximum underfill depth in the Ti-6A1-4V laser welds was about 5% or 7% of the sheet thickness for the 3.2-mm and 5.2-mm thick materials, respectively, meeting the AWS D17-1 specification. The microindentation hardness was maximum in the fusion zone and sharply decreased through the heat affected zone until reaching the base metal value.

Jan 1, 2011

By L. Rodd, C. Walker, T. Koehler

"The energy content of slag represents approximately 80% of the total energy inputs to a laterite nickel electric smelting furnace. Conventional slag handling methods produce only low grade heat and the entire thermal content of the slag is wasted. A heat recovery system proven on BOF slag in the mid 1980's can be adapted to a laterite nickel rotary kiln electric furnace (RKEF) plant. Slag is granulated using a high velocity air jet inside a waste heat boiler to produce slag granules. Granules are cooled during flight via radiation to water-cooled boiler walls and by convection to the granulation air. This system has the potential to recover 80% of the total slag energy in the form of hot air and steam.Integration of the recovered slag energy into the RKEF smelter can be achieved by a number of methods, including the use of preheated air at the ore dryers, kiln or existing power plant. Energy from the slag boiler may be used to reheat boiler feed water from the power plant or to produce superheated steam and generate electricity. The heat recovery system can provide up to 25 - 30% of the total electrical requirement of each RKEF line and a reduction in CO2 emissions of 234,000 tonnes per year.The total cost of slag heat recovery, including CAPEX and OPEX, is $2.5/GJ, which is competitive with using coal when CO2 credits are $18 per tonne. With Clean Development Mechanism (CDM) carbon credits currently selling at €13 ($20 USD) per tonne CO2, there is considerable opportunity for slag producers in regions including South America, Korea, Indonesia and Africa. Increasing fuel costs and more wide-spread legislation for GHG emissions will likely create conditions in which slag heat recovery could generate a favourable return on investment."

Jan 1, 2010

ABSTRACT It is critical that historical processes and concomitant exposures to specific nickel substances be understood because some diseases linked to inhalation of certain nickel-containing substances have a long latency between first exposure and disease onset, and because nickel substances vary significantly in their toxicological properties. A discussion of the smelting history and related processes at Vale Canada’s (Inco’s) Copper Cliff, Ontario, smelter is integral to the understanding of these processes. The post-1950 processing history, equipment, propensity for aerosol formation, operational procedures, and ventilation controls used by Vale Canada in roasting, smelting, converting, and copper-nickel separation is discussed.

Jan 1, 2013

By J. H. C. Scrimgeour, T. Toong, R. E. Hamilton

"The principles involved in the use and application of mathematical models as an aid to the development of advanced process control computer systems are described briefly. This is followed by a brief survey of known models of this kind for the simulation of mining industry processes.The main part of the paper describes a dynamic model of the flotation process developed by Canadian General Electric. Using flotation rate constants for each species of mineral and gangue, the model provides a numerical solution of the differential equations describing cell behaviour. The cell mode] is used repeatedly as a subroutine in the •over-all-plant model. The features of the cell and plant models are described.Simulation runs from the plant model show stream .assays and other indications of plant behaviour printed typically in 1-to 10-minute steps for several hours of •Operation following typical disturbances such as changes in feed rate or reagent addition rate. The simulation can :Show expected behaviour for both uncontrolled and computer-controlled plants."

Jan 1, 1970

By D. McConchie

BauxsolTM, prepared by treating bauxite refinery residues with Mg2+ and Ca2+, has an excellent ability to remove arsenic from acidic waters. The addition of BauxsolTM to sulphidic waste rock at the Gilt Edge Mine, South Dakota, reduced As concentrations in leachate water from 35 mg/L to < 0.005 mg/L; the concentrations have remained below 0.005 mg/L for the five years since the treatment was initiated. However, ordinary BauxsolTM does not effectively remove As from near-neutral water and it needs to be acid-treated or blended with small amounts of reagents, such as jarosite or ferrous sulphate, to increase the proportion of positively charged binding sites on the particles. The use of a jarosite/BauxsolTM blend can effectively treat ponded water, and As(V) concentrations can easily be reduced from over 1 mg/L to < 0.001 mg/L; As(III) has to be oxidised to As(V) for effective removal. Metal contaminants in the jarosite are trapped by the BauxsolTM and only very small amounts of the As, or other elements bound during treatment, are liberated using a TCLP leaching test. The exhausted treatment reagents meet the criteria for classification as an inert solid and do not need to be disposed of in a secure repository.

Jan 1, 2006

By W J. Dyck

Past attempts to establish an integrated steel industry on the West Coast of Canada have been unsuccessful for at least three reasons: (a) insufficient reserves of a suit-able iron ore supply; (b) a relatively small local market for iron and steel; and (c) the non-availability of an economical process to produce primary iron on a small scale. Today, the reserves of economically mineable ore deposits are ample to support a steel production of 100,000 to 200,-000 tons per annum. The local market has increased so as to be able to absorb most of this capacity. With-in the next few years, a small integrated steel plant, including the "H-Iron" direct iron ore reduction process for electric furnace charge stock production, will be able to show a profitable operation. Introduction

Jan 1, 1963

By Barry J. Turley

With over 700 large electric-drive haulage trucks operating in Canadian mining today and over 3700 in mines worldwide, most aspects of electric drive are well known. Recently, however, extensive application of these trucks to down-hill hauling in mountain mining makes it vitally important that many of us better understand the operation and proper application of the dynamic retarding feature of these vehicles. This paper is an attempt to clear up misunderstandings on this subject, to suggest precautions that mining operators should take in comparing competitive retarding systems and to challenge equipment manufacturers to evolve improvements to the important aspect of system performance.

Jan 1, 1978

By A. M. Salomon de Friedberg

With respect to impurities, HBM&amp;S&apos; copper smelter, located in Flin Flon, Manitoba, is in an unusual position. In addition to the usual concerns, the fact that copper and zinc production at Flin Flon is closely integrated results in the unique situation where feed to the copper smelter typically contains 7% to 8% zinc. This paper discusses the ramifications to copper smelter operations resulting from the marriage of HBM&amp;S&apos; metallurgical plants. Distributions of impurities (specifically Zn, Pb, Ni, As, Bi, Sb, and Cd) are presented and operating practices designed to reduce the impact of impurities on anode copper quality are detailed.

Jun 1, 1993

By F. A. Forward

Introduction The main line of ascent in the development of the nickel industry may be traced back through the International Nickel Company of Canada, Limited, to its earliest antecedents, the Canadian Copper Company and the Orford Copper Company. Mining geology is but one aspect of the overall development of this organization, and the stress it has placed on geology grew according to the need. In the early days, intensive geology was not required because ore supply was not one of the main problems of this or any of the pioneer companies. The difficulty then was to find economic methods for reducing the ores to nickel and copper, and markets for absorbing nickel in the face of a limited demand from consumers heavily prejudiced in favour of the New Caledonia product. "Very early in the history of the region it was patent to everyone that to share in the full benefits of the industry the same individuals or company must control the whole of the operation necessary to manufacture the finished product&apos; (1, p. 45). These conditions were fulfilled for the International Nickel Company in 1902 when the Canadian Copper Company (incorporated 1886), with its ample ore supply, took the initiative to merge its interests with those of the Orford Copper (Refining) Company (incorporated 1887) to form the new company which, with reorganizational changes, emerged as the producer of the overwhelming bulk of the world&apos;s nickel. The Mond Nickel Company, Limited, entered the field in 1899 with a refining process, and over a period of years acquired ore through purchase of mining properties. This Company operated successfully and independently until 1929 when its assets were joined with those of the International Nickel Company in order to permit the most economic exploitation of the Frood-Stobie orebody in which both Companies were interested.

Jan 1, 1948

By George W. Bain

Mr. Geo. W. Bain: Dr. H. C. Cooke&apos;s discussion of &apos;The Geology and Mineral Deposits of the Harricanaw and Bell River Basins&apos; possesses many of the elements of a good political address; perhaps his long residence in Ottawa has some bearing upon his method of discussing geological work. The three essential parts of the address are all included. First, the plank - "Contributed discussion on the Geology and Mineral Deposits of the Harricanaw and Bell River Basins"; second, the personal attack upon the opponent, to show antipathy to the opponent as well as to his ideas; and third, controversion of a number of statements, which have been made to appear as planks of the opponents platform, even statements and work which are in no way connected with one under discussion. In the following pages, I will confine my attention to a defense of my work in the Harricanaw and Bell River basins, leaving discussion of the other areas mentioned by Dr. Cooke until results of the re-surveys are published. It is intimated that it was impossible to make a geological examination of an area of 1,600 sq. miles on a scale of four miles to the inch (base map supplied) in three and a half months, because "the area is accessible only from the railway along the northern edge together with a few roads close to it, and from rather wide separated streams?. There is one way, known to most geologists, whereby a place can be reached other than by railway coach or motor boat, and that the oldest of all -- walking. Most of the region was reached in this fashion. The boundaries of all the 18 townships included in the map are surveyed, nine are divided into lots, and the north-south and east-west centre lines of most of the others are surveyed and have mile-posts placed.

Jan 1, 1927

By Richard N. Zimmer

This paper discusses the installation of corrugated steel linings in bored raises at Inco&apos;s Thompson Mine. The procedure for the installation of these linings is outlined and the relative advantages are compared with conventional methods of ground support. Future trends in the use of corrugated steel products are then discussed.

Jan 1, 1978

Of the twelve known ore zones on the Sunro property, acquired by Cowichan Copper Co., only the "B" and "C" orebodies of the "River Zone" had been explored sufficiently to indicate the grade and tonnage. The "B" zone was selected for initial production. The portion of this orebody above the main adit level was developed for horizontal-ring, longhole mining. Ore from the stope would be scraped directly to the coarse ore bin. The lack of a suitable mill site on surface, as well as the 8,000-ft. tramming distance, led naturally to the installation ground. I N November, 1960, a lease was obtained by Co-wichan Copper Co. Ltd. (N.P.L.) from Sunro Mines Ltd., covering the main ore (River) zone of the Sunro property. A total of twelve zones had been located on the property. Nine of these lay within the leased area. With the exception of the "B" and "C" orebodies of the River Zone, there had been insufficient exploration for tonnage and grade calculations. Exploration by previous companies had

Jan 1, 1965

By A. R. Sorta, D. C. Sego

ABSTRACT Temperature, solute, texture, and thixotropic effects on time domain reflectometry (TDR) measurements of water content in oil sands tailings are investigated. Results indicate that TDR water content measurements are influenced by temperature, residual bitumen, and percent clay in the tailings. A correction of 0.03–0.10/ °C must be applied to the apparent dielectric constant (Ka) to account for the effect of temperature. The Ka-volumetric water content relationships of slurries differ significantly from the commonly used Topp calibration equation. The age of the tailings and the addition of phosphogypsum did not influence TDR water content measurements.

Jan 1, 2013

By C. H. Hopper

DIAMOND drills have played an important part in the development of mines for many years. Recently. they have also entered the production field arid the use of diamond drills m the primary breaking of ores has become a big branch of the industry. The writer has estimated roughly that the total diamond drilling in Canada during 1942 was 5,625,000 feet, of which 2,250,000 feet, or 40 per cent, was for blast-holes. This accounts for 6,750,000 tons of ore broken, using the conservative factor of 3 tons per foot of hole. Many consider that the use of diamond drills for blast-holes is the most important advance in mine practice of the past decade, and the industry owes a great deal to the staff of Noranda Mines, Limited, for the pioneering they have done in the development of long-hole mining methods and for publishing their results. A great many mines have followed Noranda&apos;s lead. At the Waite-Amulet, Aldermac, Flin Flon, Canadian Malartic, Hoyle, and Matachewan Consolidated mines, most of the ore is broken by long-hole blasting. While the mines were developing new methods, the diamond-drill industry was developing mechanically-set bits and better machines. Through the effective use o smaller, cheaper diamonds, as well as more efficient setting, bit costs per foot are only one-half what they were ten years ago. Few people realize that a diamond bit is relatively inexpensive. The common EXT coring bit, for example, contains some 200 small diamonds, weighing altogether about 2.70 carats which, at $3.40 per carat, cost $9.20. After use, the equivalent of about 100 of these diamonds may be recovered. Therefore the true cost of the bit is only $7.00, made up of $4.60, the cost of the diamonds lost, $2.00 for setting, and $0.40 tax. The trend in machines has been toward specialization for the different classes of rock in blast-hole work. Light, high-speed machines have been developed for soft ores and higher powered machines for hard ores.

Jan 1, 1943

By R. A. Brown

RIGHT NOW the Canadian oil business is suffering from growing pains brought on by developments outside our borders. I would like, therefore, to place our industry in perspective for you in two ways. I would like first to describe it briefly and let you see it in relation to the world oil industry. Then I would like to bring it back and place it into perspective against a strictly Canadian background. Naturally, in such a discussion, it is necessary to use a certain amount of statistical material. I&apos;ll endeavour, however, to keep it to a minimum. Eleven years ago, before the discovery of Leduc, Alberta could boast of having 21,000,000 barrels of crude oil reserves. Five years ago we had 1,810,000,000 barrels. At year end, 1957, our remaining recoverable reserves totalled more than 3,000,000,000 barrels. In 1957, our potential production in Alberta reached an all-time high of 756,000 barrels a day. Unfortunately, our actual average daily production dropped from 393,000 barrels per day in 1956 to 376,000 barrels per day in 1957. And in 1958, to date, it has dropped sharply to around 300,000 barrels per day.

Jan 1, 1958