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By John R. Morgan, Peter Graham

"Onakawana Development Ltd. and Mana/ta Coal Ltd. have completed feasibility studies on a large lignite deposit located in the James Bay lowlands of northeastern Ontario. The mining plan described in this paper would supply coal for approximately a 33-year period with peak production in the early years of approximately 6.5 million tonnes per year then declining to 1.2 million tonnes in year 33. This paper describes the geology, resources, lignite quality, mine planning and related topics. LocationThe Onakawana lignite deposit is located in northeastern Ontario in the James Bay lowlands (Fig. l). The Ontario Northland Railway crosses the property and links it to Moosonee, JOO km further north, and Cochrane 180 km south. The area is crossed by latitude 50° 37', the approximate latitude of Calgary. Toronto lies 800 km south of the study area. History of Development The deposit has been known since the late 1600s when early English settlers extracted limited amounts of lignite for use at Moose Factory. The deposit has undergone sporadic periods of exploration activity in the late 1920s and early 1930s when the Ontario government drilled 116 holes, sunk two exploration shafts and published several technical and economic studies. Interest in the property was reactivated from 1939 to 1945 when the Timiskaming and Northern Ontario Railway Ltd. drilled 182 additional closely spaced holes, excavated a test pit adjacent to the rail line and installed a boiler for testing purposes. In 1965, Alberta Coal Ltd., the predecessor of Manalta Coal Ltd., first became involved. Since then a further 182 holes have been drilled and coied, and the existing test pit reopened for sampling. In 1980, various reassessment studies were launched, including geology, mine engineering, conceptual design and environmental assessment studies. The following discussions have been drawn extensively from these reports."

Jan 1, 1985

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 X. Cao, M. Xiao, M. Jahazi

Magnesium alloys have low hardness, wear, erosion and corrosion resistance. The repair of service-damaged aerospace components made of magnesium alloys is an attractive solution in terms of time and cost saving. The feasibility of applying laser beam technology to repair ZE41A-T5 magnesium alloy sand castings in the machined surface conditions was studied using a continuous wave 4 kW Nd:YAG laser system. The influence of process parameters such as laser power, cladding speed, wire feed rate and defocusing distance on the shape, size and area of single cladding beads is discussed using a process optimization software. Sound single clad beads with good geometric characteristics were obtained using strictly controlled laser process parameters. The overall results indicate that laser surface cladding using filler wire has the potential for repairing aerospace components made of cast magnesium alloys.

Jan 1, 2006

By Heidi Fauser

The aim of the project was the development of an electroforming process for the production of medical implants out of gold. To prove the applicability of this technology, tympanostomy tubes were chosen as demonstrators. These barbell-shaped tubes are usually produced mechanically; of silicone or, for higher therapeutic demands, of metal ? gilded silver or gilded stainless steel. Gold electroforming of the tubes as an alternative manufacturing process would reduce the expenditures for the mechanical preparation and lower the corrosion susceptibility significantly. To obtain electroformed gold tubes of the desired shape, the following steps are necessary: fabrication of a negative template by drilling holes with countersinks in an insulated aluminium sheet, electroforming process, removal of the aluminium by using a sodiumhydroxide solution. For the optimisation of the shape and surface quality of the tubes respectively the simplification of the manufacturing process, various parameters were tested, e.g. aluminium quality and sheet thickness, type of insulation layer, substrate processing, hydrodynamic conditions, type of electroforming electrolyte, electrodes position, etc. The manufactured tubes were characterised in view of thickness distribution, hardness, surface roughness and purity in comparison to mechanically produced reference tubes. From the results obtained during the project it can be concluded that electroforming processes can be easily adopted for the manufacture of medical implants. The time-consuming electroforming process is by far compensated by the simultaneous production of an arbitrary number of implants.

Oct 1, 2003

By W. L. Stuewe

The Dominion Steel and Coal Corporation requires enormous quantities of bricks each year for its Sydney steel plant operations. Clay brick of all types are purchased, while silica brick is made in the Company's plant at Sydney. A description of this plant was given in a paper presented by H. B. Gillis and F. C. Morrison at the 1938 Annual General Meeting of the Institute. The rock used to make silica brick was for years obtained from a quarry at Leitches Creek, about eighteen miles from Sydney. Due to the gradual deterioration of this deposit, the Corporation was forced to look for other sources of supply. In 1945, the problem was presented to the Nova Scotia Department of Mines and, through the efforts of Dr. A. E. Cameron and Mr. J. P. Messervey, an examination was made of a silica-rock deposit some six miles northwest of Yarmouth, N.S. Preliminary samples proved satisfactory, and arrangements were made with the Department of Mines to ship to the steel plant at Sydney a fifty-ton car load for the purpose of further testing. Brick made from this sample shipment stood up very well in the furnaces. At the same time, two hundred and fifty tons of silica rock from a deposit at Lac Bouchette, Que., were purchased from the Industrial Silica Corporation, and brick made from this rock also was found suitable for our requirements. Comparative transportation costs, however, led to a decision to open the Yarmouth deposit. The silica rock, or quartzite, of this deposit outcrops at Chegoggin point along what is known as the 'Pembroke shore', a northerly trending section of the coast-line at the extreme southwest of the Province, in Yarmouth county. The country here is fairly flat, with elevation averaging about twenty feet above high tide, and is for the most part mantled by a growth of brush and some scrub trees, chiefly small fir. Bed-rock is generally concealed beneath three to four feet of clayey soil, but scattered outcrops of the quartzite indicated that a band of this rock, some 260 feet wide, extended inland in a northeasterly direction from Chegoggin point at least to Utleys lake, a distance of about three miles.

Jan 1, 1947

By A. L. Irwin

THE disposal of tailing or waste material, which is generally a very large proportion of the ore treated, is a major problem in the location and operation of any concentrating enterprise and especially so where the life of the operation is expected to continue for many years. Many factors need to be taken into consideration in the selection of a tailing site, chief among which are economical handling of the material, subsequent re-treatment of the tailing, and precaution against stream pollution by waste water. The final location of many mill sites bas been governed largely by the selection of a sui table area for tailing storage. The Sullivan concentrator of the Consolidated Mining and Smelting Company is situated about three miles from the Sullivan mine at Kimberley, B.C., and one of the deciding factors in its location at this distance from the mine was the availability of a suitable area in which tailing could be deposited. In view of the indicated long life of the property, a far-sighted policy bad to be adopted in the matter of tailing storage, for not only would it be necessary to accumulate a huge tonnage of finely ground material, but also reclamation for iron recovery at some future date bad to be considered. Some idea of the extent of the problem may be grasped when it is noted that, by the end of 1938, over 18,000,000 tons of tailing bad been impounded in an area of some 200 acres.

Jan 1, 1939

By Y. G. Seredkin, A. A. Vasiliev, A. Y. Senchenko, A. V. Aksenov

"Autoclave oxidation, bacterial and chemical liberation, roasting, acid oxygen processes, atmospheric oxidation prior to cyanidation are applied to process refractory sulphide concentrates. It is obvious that the processes with the maximum effect regarding gold recovery are those in which complete destruction of sulphides takes place and gold becomes accessible for further cyanidation through liberation from sulphide “capsula”. But the significant recovery increase is often accompanied by a process complexity, high expenses for equipment purchase and maintenance. It makes material processing costinefficient. Process optimization has led to progress in ultrafine grinding, bacterial and autoclave oxidation processes. In our opinion sulphide atmospheric oxidation processes are the most interesting as oxidation there runs without high temperature (up to 100°?) and excess pressure (open units), and with acid environment close to neutral. The process of sulphide concentrates treatment named “Albion” (Albion Process™) represents a combination of ultrafine grinding and oxygen oxidation without pressure and external heating. The process has a number of advantages: sodium cyanide consumption decrease during gold leaching and high ecological compatibility. TOMS institute in collaboration with Glencore Technology Pty ltd (Australia) tested Albion technology aiming at liberation of finely disseminated gold from flotation concentrate produced from refractory ore of one Russian deposit. The testing has shown that Albion technology makes it possible to process refractory products with quite small capital investments. It enables involving medium and small refractory gold deposits into processing.INTRODUCTIONThe considerable part of the world Au-bearing reserves is present by refractory ores with finely disseminated gold. Gold in such ores is often associated with sulphide minerals and locked in so called “sulphide capsula” since it is closed inside dense sulphide grains and inaccessible to recovery by cyanidation. To treat refractory sulphide concentrates containing gold a number of processes were developed and they can be divided into three groups (Figure 1)."

Jan 1, 2016

"With the globalization of the mining industry, many companies are now seeking to invest in underground diamond mines, with the purchase of small diamond pipes being seen as particularly attractive. However, recent experiences in South Africa have shown that many projects fail due to a lack of awareness of the hazards associated with diamond mining. In this paper three significant hazards are dealt with — mud rushes, block crushing, and implementation of an inappropriate mining method. Measures that assist in the prevention of these three hazards are given.IntroductionFor over a hundred years, South Africa has been seen as the centre of the diamond mining industry, possibly having the largest number of operational underground diamond mines in the world. Despite the fact that this industry has been dominated by large mines of De Beers Consolidated Mines Limited, many small underground mines have operated profitably for a number of years, exploiting diamondiferous fissures and pipes. In the last decade there has been renewed interest in these small operations from international companies. However, many of these projects have not realized their full potential owing to a lack of appreciation of the hazards inherent in the operation of a diamond mine.Hazards Associated with Diamond MiningIn the development of a diamond mine, the mining company must be aware of the hazards associated with diamond mining. There are three main hazards: (1) mud rushes; (2) block crushing; and (3) selection of an inappropriate mining method (not a natural hazard, but a planning induced hazard). Each of these hazards will be dealt with in turn in the following sections."

Jan 1, 2000

By S. Minamiguchi

Grain refinement is effective to enhance strength and ductility of metallic materials. However this advantage has not been utilized fully for magnesium alloys in industry because microstructure control through thermomechanical treatment is difficult owing to their poor deformability. The authors proposed a high-speed heavy-reduction rolling for production of Mg alloy sheets. It was found that the deformability is significantly improved at high speed and that the thickness can be reduced 60% by one-pass operation even at room temperature without fracture at the rolling speed higher than 1000 m/min. In this study, commercial AZ31B sheets were rolled at 2000 m/min between room temperature and 350°C, and quenched immediately after the rolling. The sheets rolled at 200°C show the finest recrystallized microstructure with the mean grain size of 2.2 Rm. They show outstanding mechanical properties with the tensile strength of 293 MPa, and the elongation of 25%. It is concluded that high-speed rolling is very advantageous for grain refinement and improvement in mechanical properties as well as deformability and productivity.

Jan 1, 2006

By George J. Thompson

This pa per deals with the internal characteristics of steel and its response under cold northern temperatures. General maintenance procedures and specific repair techniques are covered.

Jan 1, 1973

By W. R. Lindsay

Anyox, where the Hidden Creek mine of the Granby Consolidated Mining, Smelting and Power Company is located, is situated on an excellent deep-water harbour in Granby bay, at the head of Observatory inlet, about 600 miles from Vancouver and 90 miles north of Prince Rupert. Anyox is the Indian name for the little stream which empties into Granby bay, and means 'hidden creek'. The Ore-Bodies The ore is a replacement deposit and occurs at and near the contact between argillites and a later intrusive greenstone. This contact locally has a general north-and-south trend, an irregular westerly dip, and in the vicinity of the ore-bodies there has been intense folding, accompanied by faulting. The mineralizing solutions supposedly were derived from the Coast Range granite batholith, distant one to two miles to the east and north. The whole area is cut by many dykes of varying widths, which seem to have had but little part in the ore deposition.

Jan 1, 1929

By B. T. Lu

The corrosion and wear properties of a series of chrome white iron (CWI) castings were study using electrochemical and low-stress sliding abrasion tests. The results confirm that the corrosion resistance of these materials is largely dependant on the quantity of chromium in the matrix, while the wear resistance is mainly controlled by the volume fraction of chromium carbides. A pseudo-wear/corrosion map is developed to identify alloy compositions that may be suited for erosion/corrosion conditions.

Jan 1, 2005

By A. L. Karyakin

The report focuses on the process measurements of the mass of rock in the bucket power shovels and dragline excavators. The mathematical models are suggested of AC and DC electric drives of excavators. These models are a basis for calculation methods of the electric drive electromagnetic torque. The design schemes of mechanical equipment of excavators considered to account the situation of bucket in the plane of the boom. The methods of static moment allocation and identification of the excavator technological operations are developed. The results of the work are experimentally tested on power shovels with bucket capacity of 12 and 18 m3.

Aug 1, 2013

By T. Winkler

This paper presents elements of the Virtual Working Environment for identification of hazards occurring in the mining industry. The Virtual Working Environment includes models of machinery and models of anthropometric features. Examples are given for identification of technical hazards at the design stage using the following computer programs: Finite Elements Method, Multibody System Analysis and Human Body Modeling. One of the methods to improve work safety at the machine and equipment maintenance stage is to share design and operational knowledge in a form of an Interactive Electronic Technical Manual (IETM). An IETM is created using so-called reusable knowledge elements connected by relationships. A metamodel created in Unified Modeling Language is one of the forms for description of these relationships. The metamodel can represent, for example, interrelations between elements of repair procedures. Examples of procedures realized during the replacement of a damaged cutting bit are presented and discussed.

Aug 1, 2013

By R. W. Brock

This subject is too broad and comprehensive to be dealt with adequately and authoritatively in this paper. It calls for the knowledge and experience of many men, but the results from such collaborative effort would be of great value, particularly if similar reports of the principal mining districts of the world were made on a standardized basis so that conditions everywhere might be directly and accurately compared. In considering conditions affecting mining in British Columbia, unfavourable as well as favourable factors must be taken into account. The unfavourable are apt to loom large and to be exaggerated rather than minimized; for it is human nature to see the blackness of the cloud rather than the silver lining; to think that one's own undertaking is beset with peculiar difficulties, and to attribute lack of greater success to out-side causes rather than to personal shortcomings. It should be recognized, however, that there is no country where the conditions for mining are ideal. The ideal mining country is the product of imagination, invested with every favourable condition found anywhere, but with none of the unfavourable conditions that are always present in reality. So if British Columbia has some handicaps to the industry, it is in good company. What is important is that the advantages compensate for the disadvantages, that the balance will compare favorably with that of competing states, for mining, like every other industry is competitive, and the cost of one's product must have a definite relationship to its price in the world's market.

Jan 1, 1924

By A. D. Akerman, D. D. Young, G. R. Baiden

The development and maintenance of underground roadways are increasingly important aspects of the modern mining process. With the trend toward automation and track-less mining, roadbeds capable of with standing increased wheel loading have proven necessary to maintain high vehicle speed and reduced maintenance costs. Concrete has been used successfully on some roadways in order to obtain the required characteristics. However, this solution usually involves unacceptable expense. The objective of the Road Router project was to create a drift floor profiling machine capable of cutting a smooth surface out of the existing rock floor of development drifts and ramps. This surface would provide a durable, high strength, low rolling resistance roadbed that would allow for reduced operating cycle times and lower maintenance costs of scoops and haulage trucks. The Road Router has the potential to offer an alternative to concrete with substantial cost savings.

Jan 1, 1997

By F. Charette

Instrumentation has been developed that can monitor the strain applied to a D-Bolt up to 7.5% elongation. The technology far exceeds the limit for foil resistance strain gauges. In the laboratory the instrumentation has provided insight into the fundamental behaviour of the D-Bolt following yield. Currently the instrumentation is undergoing field trials at a number of Canadian Mines. Discussion on field results is provided with regards to significance, reliability and temperature effects.

Aug 1, 2013

By C J. Coveney

This paper, after a brief introduction to the mineralization and structure in the mine area, outlines the methods now being employed for grade control at Bethlehem Copper Corporation. Sampling, subgrade drilling, blasting and the actual outlining of the ore are among the topics covered. The paper concludes with a summary of the results obtained, showing a reduction in dilution and an improvement in the grade of the copper ore going to the mill. Introduction T HE Bethlehem property is located in southern British Columbia in the Highland Valley about 30 miles southeast of the town of Ashcroft. The property is located within the Guichon batholith. The rock comprising the batholith is a massive, coarse-textured diorite, which, at Bethlehem, has been intruded by a younger quartz diorite, porphyries and breccia, referred to as the "Younger Complex." Mineralization, consisting of chalcopyrite and bornite with minor pyrite and molybdenite, occurs as disseminations, fracture fillings and coarse blebs. The ore zone lies close to the Guichon -Younger Complex contact where, prior to the development of the breccia, the rocks were shattered and jointed. Subsequent mineral

Jan 1, 1965

By H. Lee

Recently, the effects of global climate changes have become top concerns for governments? decision making regarding infrastructure investments. Extreme weather events that exceed the capacity of existing systems have considerably increased in frequency, and the potential effects of changing trends in temperature and rainfall on infrastructure are difficult to ignore. It is essential for governments to estimate the costs and benefits of adaptation to climate change to properly assess the financial feasibility of infrastructure adaptation strategies. This paper proposes a framework for estimating the economic aspects of infrastructure adaptation to climate change. The framework is composed of three steps of implementation: establishment of alternatives for infrastructure adaptation, performance prediction of infrastructure using future climate scenarios, and asset valuation based on costs and benefits. The first step specifies target assets, their adaptability to climate change, and applicable adaptation technologies. The second step evaluates the effects of climate change on the performance of infrastructure. The last step determines the optimal adaptation strategies among various alternatives based on their net benefits. The framework reasonably incorporates future climate scenarios into the estimation processes for climate change effects and provides a basis for budget allocation for governmental infrastructure investments. The framework is expected to assist government decision makers in establishing adaptation strategies in a rational manner under uncertain future climate change.

Aug 1, 2013

By Gautier Njiekak

The current study provides an experimental approach that aims at documenting the effects of different phases of CO2 (gas, liquid, supercritical fluid) on rock seismic responses. This has implications on obtaining quantitative estimates of fluid saturations for geological storage. The ultrasonic pulse transmission technique is the underlying methodology used in this work. Unlike previous rock physics studies involving CO2 as pore fluid, care is taken to fully saturate the studied samples and also to separate pore fluid effects from pore pressure build-up effects during the experiments. This allows to record seismic effects that are solely reflective of changes in the pore fluid properties. Measurements were done on a CO2 saturated Berea sandstone. Laboratory results show P- and S- waveform variations (velocity, amplitude) in response to CO2's varying phase state. Overall, CO2 phase changes (gas to liquid and gas to supercritical fluid) are marked by a drop in velocities, with the drop being smaller and less immediate over the gas-supercritical fluid transition than over the gas-liquid transition.

Jun 1, 2012