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By M. B. Dusseault, A. Pirayehgar

"There is concern that hydraulic fracturing (HF) near an existing critically stressed fault could trigger slip and generate a seismic event of significance. To this end, a mathematical discontinuum model representing a naturally fractured rock (NFR) mass containing a fault is created, and fault slip response to fluid injection is studied. UDECTM is used as a Discrete Element Method (DEM) approach to define the seismic moment, and also to assess the influence of injection and slip on further shear slip propagation. In most of the simulations, slip and dilation take place along a number of oriented fracture surfaces, so it is reasonable to assume that in a real case, microseimic emissions would accompany each slip “event”. The moment magnitude scale (Mw) is used to measure the size of the microseismic event in terms of the energy released. Seismic moment is a measure of the total energy (work) released during a seismic event and is used to measure its size. From another aspect, the injection energy is calculated as the total energy required for achieving the hydraulic fracturing; this is viewed as energy to open fractures against the ambient stress field and much of it is potential stored energy that can be released and create discontinuities (work of fracture), deformations (W=F·d), heat and radiated seismic energy. A small amount of the total released energy is transformed to radiated seismic energy and another small amount results in tensile fractures. Fracture energy is used to calculate the work required to create fracture surfaces. Comparing the energy release by fracturing or seismic events indicates their contribution to the total amount of released energy or total work. The amount of energy associated with the stick-slip event is small compared with the overall work done to generate the distortions (i.e. increases in aperture by forcing them open) in the rock mass, and much of the energy in slip is lost as heat from the plastic deformation, rather than as radiated seismic energy.Microseismic monitoring shows the spatial distribution and magnitude of seismicity associated with slip of bedding planes and natural and incipient fractures. Work calculations have been undertaken to look at the various sources of energy storage (elastic strain energy) or dissipation (slip), and likely the energy losses from viscous dissipation could be addressed as well, helping to clarify HF processes in NFRs."

Jan 1, 2015

By P. Harvey

"Following initial discovery in 1991, BHP Billiton Diamonds Inc. opened Canada’s first diamond mine, the EKATI Diamond Mine (EKATI) in the Northwest Territories on October 14, 1998. Four short years later, on November 29, 2002, saw the opening of North America’s first underground diamond mine, the Koala North mine. Nestled between the original Panda open pit and the new Koala pit, which is in the early stages of production, Koala North represents the only underground kimberlite mining venture in Arctic conditions outside the new underground mines being developed by ALROSA in the Yakutsk region of eastern Russia. Extensive underground kimberlite mining has been practiced in the Republic of South Africa for much of the 20th century and continues today.Underground mining represents a key component of the long-term business plan for EKATI. As various open pits reach their economic limit, continued recovery of high-value ore at depth is dependent upon the ability to productively mine the kimberlite pipes by underground methods. As a function of its location, size, and value, the Koala North pipe is ideally positioned to host the first underground mine at EKATI. Koala North is designed and approved as a learning mine, from which to gain valuable experience in preparation for the potential mining of other larger, higher value pipes by underground methods in the development, the Koala North mine is well into its production ramp-up phase and currently producing at around 1,200 t/day from the first two production levels."

Jan 1, 2005

By John L. Hatton

The author will introduce and describe the nature of Fiberglas-Reinforced Plastics. Successful applications of corrosion-resistant structures will be shown and described, including pipe, ducts, tanks and other equipment. These structures are generally designed to handle corrosive liquids and gases and have proved both satisfactory and economical in service in various industries in Canada. The specification of structures will be discussed in relation to materials, construction and workmanship, physical properties and methods of testing.

Jan 1, 1970

By Sydney H. Ball

It is a peculiar anomaly that while the world uses the term "rich as a gold mine" as the superlative figure of speech descriptive of wealth, the shares of gold mines are not as popular investments in America as certain of them should be. One of the most able of Manhattan's bankers is a director in an investment trust with a portfolio the value of which has gone the way of other such portfolios. Luckily a couple of years ago a few hundred shares of Homestake were purchased, and since then the trust has not only received therefrom satisfactory dividends but has benefitted from a large appreciation in their value. At each directors' meeting, however, the banker in question, Cato-like, suggests the sale of these shares, gold shares being, in his opinion, too speculative to be included in the portfolio of any trust. A short time ago the financial pages of one of our great metropolitan papers featured an article listing the corporations still paying dividends at the 1929 rate. Gold-mining shares were, the article stated, excluded, although in reality every gold mine on the New York Stock Exchange paid higher dividends in 1932 than in 1929. This 'Alice in Wonderland' treatment of the gold-mining shares is admittedly a bit confusing to those of us who believe that the shares of certain gold-mining companies have a rightful place in any well diversified portfolio. It should, however, here be recorded that whereas, fifty years ago, in America, gold-mining shares were considered by the public as instruments of nefarious gambling, now shares of the better gold mines are sought by astute investors. In England for well over a generation their value as sound investments has been widely recognized.

Jan 1, 1933

By A. M. S. Hussein, B. E. Rogers

Progressively more stringent emission limits and advances in regulations and enforcement have made air compliance more difficult for metallurgical facilities. This has historically required improved collection and treatment of stack sources. Fugitive emission reductions are now increasingly required to achieve compliance. Typically small in magnitude, fugitive emissions have a disproportionate impact on ground level concentrations, can be visible to the public and can influence workplace health and safety. Moreover, these emissions are complex, as they are spread over multiple sources, distance and time and are affected by various activities and conditions. As such it is difficult to find, define and monitor these emissions and their impacts. This difficulty translates to the design of emission reduction measures and operational requirements. This paper presents an overview or ‘heuristic’ of fugitive emissions management for compliance in existing operations. This includes aspects such as the impact of regulations on project scope, approaches to developing a comprehensive emission inventory, considerations for solution development and the plant’s role in sustaining compliance once achieved. Case studies are presented to demonstrate how portions of this approach have been applied.

Jan 1, 2015

By J. M. Cummings

DURING the past year, the writer has investigated the treatment of a variety of British Columbia tungsten-bearing ores. Much of the test-work described in this paper was carried out in collaboration with Mr. A. G. Lyle in association with the British Columbia War Metals Research Board at the University of British Columbia. The remainder was completed in the laboratories of the Department of Mines at Victoria. Two mills in the Province are at present treating tungsten ores. Descriptions of these are included through the co-operation of Messrs. S. Gray (1) and A. A. Almstrom (2). MINERALOGY, OCCURRENCE, AND SPECIFICATIONS In the present paper, attention is directed solely to scheclite, inasmuch as known occurrences of other tungstcn minerals in British Columbia are of mineralogical interest only. The properties of scheclite are listed below: Percent W03 .. 80.6 Tenacity ...... Very brittle Çrystallization Tetragonal Lustre ........ Vitreous to resinous Cleavage ...... Good in 4 directions Magnetism ... Non-magnetic Specifie gravity 6.05 Diaphaneity .. Transparent to translucent Hardness. . . . . . 4.5-5.0 Scheelite may contain as much as ten per cent of molybdenum in solid solution, but most of the specimens from British Columbia examined by the writer were relatively pure.

Jan 1, 1943

By E. Peters

Roasting processes are divided into several elementary mechanisms, any of which could be significant or pre-dominant in a particular roast. The elementary processes considered in-elude beat transfer, gas-solid inter-actions with accompanying mass transfer between the bed and furnace atmosphere, vapor phase transport processes in solid-solid interactions, and solid phase diffusion processes. Examples are chosen of processes in which one of these mechanisms pre-dominates and some recently obtained data is presented to support the existence and significance of these mechanisms. Proposals are also made for future research in these areas, and for utilizing the information in the improvement of roaster capacities’ OASTING of ores as a preparative treatment for smelting or leaching has been practiced for so long that its origin has been lost in antiquity, but little has been under-stood of its basic nature until fair-ly recent times. The nominal chemistry of roasting processes is now understood; that is, the initial chemical com-pounds present in the ores or con-

Jan 1, 1961

By F. Grant

"General *The mining experiences of the coal mining industry in Western Canada have been extremely varied, with the mining companies having to adjust their operations or fail due to the harsh economy of the country in the first part of the century. The bituminous or mountain mines had the railways as main consumers with, at times, optimism that potential steel producers would require metallurgical coal. The prairie and foothills mines mainly provided household fuels, with the fine coal sold to local thermal power plants at discounted prices. In practically all cases fuel competition was very keen, and the less successful mines ceased operations in short-time spans. Knowledge of the parameters that governed the success or failures of the past coal operations should be of value to the present and future mining companies. The initial coal mines were small and were started to supply local demand. These mines had little in the way of capital machinery, engineering, or transportation equipment; therefore the mining methods and mine plans were very simple. The first industrial-sized mines imported most of their management and mining methods from other mining areas, mainly Great Britain. It took time to change the bias of management and mining methods to the requirements of strata characteristics, with rapid closure to those mines that were slow to adapt working methods. The main markets for coal were for household fuel, thermal power plants and railways, with very few other industrial markets developed. The economy of the period was harsh and cyclic and the coal mines were affected more than most industries by these boom and bust periods. It led to the survival of the fittest or the most efficient. Due to the economy, mechanization was introduced to the mines very slowly, with the inability to sell coal fines at a profit being another reason for the delay. Manual labour with hand tools was the main means of production. The work was heavy and arduous, and the pay was based on contract coal tonnage; therefore both men and management paid close attention to details so that nonessential work could be eliminated. Mine openings were dimensioned so that coal could be loaded easily by hand and support requirements were kept to the minimum. Transporting and handling the timber supports required heavy labour; thus the most efficient dimensions were chosen to suit the strata. On the other hand, during the main production seasons the mines tried to make the strata stress work for them so that the pressure was kept on the coal face to keep the coal loose while the strata, a short distance back, was induced to cave to minimize the abutment stresses. This caused mining to be an art, using skills developed by experience with the strata. This led to the development of efficient mine layouts with the openings dimensioned to the strength of the strata and the type of support available. The lack of capital and mechanization, and the manual labour, induced the mines to correlate their service and haulage systems with their mining methods. This caused many innovations that proved very practical."

Jan 1, 1985

By D. Pacey

"This paper reviews the installation, start-up, and operation of a comprehensive monitoring and targeting management technique in which all plant utilities (i.e., electricity, natural gas, compressed air, and water) are managed as controllable resources in the same way that raw materials, mined ore, personnel and capital are managed.The essential elements of monitoring and targeting (M&T) include:•gathering in a systematic, disciplined way the utility information by energy account centres;•closely monitoring the utilities used in each centre and comparing them with production on a common time base (e.g., kWh/ton per day);•bench marking and target setting to pro-vide attainable energy reduction goals which can be further refined as they are achieved; and•establishing an implementation plant that may provide efficiency enhancing benefits to various operating areas within the plant.The M&T system will reduce utility consumption per unit of production on a continuing basis.This would translate into sustained operating cost and waste. M&T will also provide better information for assessing the plant operation and progressively implementing further enhancements."

Jan 1, 1997

By W. S. Fyfe

Gold is mobilized and precipitated in a wide variety of environments ranging from those of weathering and biological phenomena, to pluton emplacement to deep metamorph ism . But it appear that pervas ive leaching of large rock volumes fo llowed by the focussed di charge of typically low salin ity flu ids is frequently involved. There are great gaps in our knowledge, particula rly with re pect to gold in very high temperature fl uids generated at near Moho depths. But uch flu id may play an important part in Archaean pluton associated lode gold deposits whe re ultra high temperature fluids, rich in C02-CO-COS, may be associated with magma underplating and crustal assi mil ation processes (sag subduction) associated with very den e ult ramafic magma . Other environment with great potential include those of major thru t fau lt and strike slip fa ult s where large quant ities of fluids are mobilized .

Jan 1, 1986

By D. H. Stonehouse

Of the f ive Canadian cement producing regions- Atlantic, Quebec, Ontario, Prairie and Pacific-Ontario has the greatest capacity and normally produces the most cement. However, during the last 5 years the greatest activity within the industry in Canada has been in the Prairie and Pacific regions where major capacity increases have taken place. Most Canadian cement companies produce normal Portland, high-earlystrength Portland and sulphate resisting Portland cements. Some companies also manufacture moderate Portland cement, and low-heat-of-hydration Portland cement. Escalating energy costs highlight the need for technology research into more energy-efficient equipment for the energy-intensive cement industry. The industry is well integrated and plants are well situated to support construction in Canada. Expansion into the United States has become common during the past decade.

Jan 1, 1984

By H. L. Cameron

Introduction Since the beginning of gold mining in Nova Scotia in the year 1860, the biggest problem o the mine operators has been to find and follow the ore zones in the narrow quartz veins. It was early recognized that all veins were not gold bearing and that, in those that were, the commercial ore was confined to limited zones. A large number of geologists and mining engineers have been interested enough to give time and thought to the problem, but, until the last four or five years preceding World War II, they were handicapped by lack of exact data from mining operations. The necessary data could only be obtained by daily checking of underground operations. Such daily checks were instituted at a number of mines during the period 1935-40 and, in every case, were successful in delimiting the ore zone or zones for the particular mine. The present paper deals with the results of this work as applied to practical ore finding. It is an attempt at extrapolation, from observations in the four districts with which the writer is personally familiar, co other districts in which similar conditions or structures are reported.

Jan 1, 1947

By Minghui Li

China is the largest coal producer in the world. In 2012, the coal production in China is 3.65billion tonnes, accounting for approximately 49% of global coal production. The raw coal production in 2012 was 3.8% more than the year 2011. 56% of total raw coal has been washed. The increase in raw coal production also promotes technology to be developed and brings separation capacity become larger and larger in coal processing in China. At present, over 40 extra-large scale coal preparation plants (each plant has capacity of more than 10 Mtpa) are in operation in China, the largest one is 32.5 Mtpa. Heavy medium separation are widely used in new built coal preparation, the washing limit for thermal coal feed lower and lower, the equipment selection tends larger which brings the whole washing system simplified, the local equipment developed and manufactured are more and more used. By discussing designs of several typical thermal coal preparation plants and coking coal preparation plants in China, this thesis introduces the current design of China?s extra-large coal preparation plants, and sums up the prevailing design features and trends of extra-large coal preparation plants.

Aug 1, 2013

By Patrick Wong, Gareth Hatch, M. A. Halim, V. I. Lakshmanan, Darcy Tait

"This paper describes development of an integrated chloride process for separation and purification of REEs. The process includes atmospheric leaching of ore/concentrate with mixed chloride lixiviant containing HCl and MgCl2 followed by bulk recovery of REEs, dissolution of the bulk intermediate product, and separation of individual REEs by solvent extraction (SX) process steps. Mixed chloride leaching technology provides the opportunity to regenerate the lixiviant, while the addition of MgCl2 in HCl enhances the hydrogen ion activity by orders of magnitude increasing REE extraction efficiency at a lower concentration of HCl. An individual REE separation process developed by Innovation Metals Corp. is being piloted at a state-of-the-art facility at Process Research ORTECH Inc. in Mississauga, Ontario, Canada. The SX process includes the separation of light REEs (La – Nd), medium REEs (Sm – Gd) and heavy REEs (Tb – Lu plus Y) from leach liquor followed by individual REE separation. Each SX circuit proceeds by multistage extraction followed by scrubbing and stripping. The process is chloride based and reagents are recycled, reducing waste generation and optimizing water usage to reduce environmental impact.INTRODUCTIONRare earth elements (La to Lu plus Y) exhibit a range of unique magnetic, electronic, catalytic and optical properties. Due to these special properties, the application of REEs is increasing and they are found in components for wind power generation, hybrid electric cars, catalytic converters, and many electronic devices.Rare earth elements (REEs) are commonly divided in two groups: light rare earth elements (LREEs) and heavy rare earth elements (HREEs). Light rare earth elements include elements from lanthanum (La) to neodymium (Nd). Although promethium (Pm) is considered an LREE it is unstable and scarcely occurs in nature and is generally excluded. Heavy rare earth elements include elements from samarium (Sm) to lutetium (Lu) plus yttrium. Although rare earth elements are not rare and the rare earth oxides are scattered around the globe, over 95% of REEs+Y are currently produced in China (Pitts, 2011). On one hand the Chinese government is restricting the export of rare earth elements and on the other hand the demand for REEs+Y is increasing in the rest of the world. This has created an imbalance in the supply and demand of rare earth elements and has led to a rush for developing new rare earth projects."

Jan 1, 2016

By Kenneth L. Norris

Stonegate Agricom Ltd. is currently conducting exploration and development drilling of the Paris Hills Phosphate Project (Paris Hills Project) located in Bear Lake County, southeastern Idaho, 3.2 km west of the towns of Paris and Bloomington, Idaho. The project is located adjacent to a highway and 19 km by paved highway to Montpelier, Idaho where the Union Pacific Railroad system is located. Power and water are available locally. The nearest metropolitan centre is Salt Lake City, Utah approximately 225 km by road to the south-west of the property. The Paris Hills Project encompasses an area of approximately 856 hectares. Property holdings consist of three (3) patented lode mining claims and 16 contiguous fee parcels (some with federal phosphate leases). Active open pit phosphate mining operations are located in surrounding counties in south-east Idaho and are owned and operated by Agrium Inc., Monsanto Company and J.R. Simplot Company. The Paris Hills Project is located near the centre of the Western Phosphate Field which constitutes the most extensive phosphorite beds in the United States. Phosphate beds of the Western Phosphate Field occur within the Phosphoria Formation of Permian age and extend over an area of more than 350,000 km2 including extensive areas of Idaho, Utah, Wyoming and Montana. At Paris Hills the phosphate mineralized beds occur in the overturned limb and the horizontal limb of the Paris Syncline. Grades and thicknesses in both the western overturned limb and the eastern horizontal limb of the anticline are similar. The vast majority of potential mineralization occurs in the horizontal limb which underlies most of the property holdings. Mineralization in the overturned limb has a strike length of over three (3) kilometres and extends from the surface to a depth exceeding 300 m depending on location along the north-trending strike of outcrops. Depths of the horizontal limb range from surface along the north side of Bloomington Canyon to estimated depths of 915 to 1,035 m at Paris Canyon. The property contains an Inferred resource of 109.6 million tonnes at 23.6% P2O5 over two mineralized horizons. The phosphate zones have a strike length of over 3 km and extend from surface to a depth of at least 900 m. Drilling commenced late in the 3rd quarter of 2010 and is planned to continue through 2011. The drilling was planned to target an area of potentially higher grade phosphate mineralization and better define and upgrade the current resources.

May 1, 2011

By Yin Wang, Lin Li, Zhongwei Bi, Like Wei, Wen Li, Shaogang Li, Bin Zhang, Hongjie Li

Presently,Many long-wall fully-mechanized faces in shallow depth coal seams are below room and pillar goaf in Shendong mining area. When the working face is advanced out of concentrated coal pillar in upper room and pillar goaf, strong strata behaviors often cause support crushing accident. Aiming at a support crushing accident which happened in Shigetai coal mine of Shenhua group in Shendong mining area, this paper analyses the stress transfer process while mining out of concentrated coal pillar by numerical simulation software FLAC3D. According to the feature, simplifying the roof of upper room and pillar goaf as supporting-beam structure explains mechanism of large area collapse in room and pillar goaf roof. Based on the feature of supporting-beam structure, deep-hole blasting concentrated coal pillar technology is proposed to control the strong strata behaviors in Shigetai coal mine. The blasting control effect is confirmed through characteristics of strata behaviors, growth circumstance of ground crack and multi-point extensometer monitoring results. By using control technology, Shigetai coal mine has been successfully avoided support crushing accident.

Jan 1, 2015

By R. D. Brown

The first step in achieving a rationalization of Canada's crazy patch-work quilt of mining taxes and policies was achieved with the release last November of a major federal-provincial report on the taxation of the Canadian mining industry. The Report, prepared by a group of federal and provincial civil servants, sets out a concise and informative discussion of the major taxation and incentive issues facing the mining industry, and puts forward major recommendations for more rational and moderate taxation policies. It will be considered by federal and provincial Finance and Resource Ministers for possible action by the respective governments. The Report was prepared in response to a directive from the federal and provincial First Ministers in February 1978 to review the federal and provincial taxation of the resource areas. Although the Report is more successful in identifying problems rather than concrete solutions, and reflects some continuing differences of opinion between the governments involved, it does represent an important first step in a comprehensive review of our resource tax policies. This article summarizes the Report, which is some sixty pages in length. Although a detailed discussion of it is beyond the scope of this article, the report itself is recommended reading for those concerned about the current state of the Canadian mining industry.

Jan 1, 1979

By Tao Long

Recently, the great amount of funds has been invested in the reconstruction of damaged infrastructure and house of subsidence area of coal mine and mine reclamation. This is a benevolent and popular work, which is highly praised. However, because of complicated collapse area problems in China, especially the less integrated control research in the collapse area of metal mine, and the technological weakness, how to effectively control the subsidence area, restore landscape and ecological environment, and utilize the abandoned mine land, are major issue related to the mining area of sustainable development. The research situation about the formation of metal mine collapse area at home and abroad is reviewed, and then the effect of the collapse area on the mine safety and ecological environment, the existing technical problems and development direction are analyzed. Lastly, the technical measures of the collapse area control and cooperative underground mining is put forward.

Oct 1, 2010

By F. Ajersch, A. R. Hekmat

Apparent viscosities of hypo-eutectic (Al-7% Al) and hyper-eutectic (Al-35% Si) binary alloys were measured in the semi-solid state using a Couette type viscometer at variable shear rates. Analysis of the microstructural evolution demonstrates the differences in the rate and degree of attrition of the primary phase particles which are characteristic of the thixotropic nature of the semi-solid alloy. It was observed that the Si primary phase in the hyper-eutectic alloy is much more difficult to fragment than the dendritic a-Al phase in the hypo-eutectic alloy. For the case of the a-Al, the dendritic structure is broken down by attrition and fracture of the dendrite arms whereas the fracture of the Si hexagonal crystals in the hypereutectic alloy occurs along the {100} and {110} cleavage planes. Results are presented for fixed solid fractions of the primary phase at isotherm condition for each type of alloy.

Jan 1, 2006

By A. Aubin, H. Yang, G. Zaluski

The Athabasca Basin of northern Saskatchewan and Alberta is an exceptionally rich metallogenic region, hosting more than 2.8 B lb U3O8, of which over 927 M lb U3O8 have been mined out since extraction first started in the late 1970’s. A detailed compilation of several empirical features of 85 deposits located within the basin was conducted in order to understand the distribution and variability of the geological characteristics of the mineralization and its associated alteration. A new empirical classification was devised based on four parameters: 1) geometry of the mineralization (dimensions and relation to the unconformity surface), 2) size, grade and metallurgical complexity of the mineralization, 3) lithostructural setting, and 4) extent and nature of associated alteration haloes. This compilation defines the footprint characteristics of the Athabasca Basin deposits, which guides decision-making processes from early exploration and discovery to resource expansion and extraction.

Jan 1, 2020