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By Lin-fang Shen, Shao-jun Li, Zhi-liang Wang

"The meso-structure of real soil consists of numerous particles with different sizes, while the traditional reconstruction method of quartet structure generation set (QSGS) produce relatively uniform soil particles resulting in significant discrepancy between the actual structure and reconfiguration model. In order to remedy the deficiency, the QSGS is improved by considering the influence of porosity and autocorrelative function of soil, which make the models closer to the real soil. Based on the reconfiguration model, Lattice Boltzmann method is combined in the algorithm to conduct further simulation of fluid flow in soil pores. The D2Q9 model is applied to construct the two dimensional model for simulating mesoscopic seepage field of saturated soil by setting the non-equilibrium extrapolation scheme at the inlet and outlet boundary, and the bounce-back scheme at the soil particles boundary as well as the left and right boundary. According to the case study, the proposed program is realized to simulate mesoscopic seepage field of reconstructed soil with constant inlet seepage velocity. The results show that the seepage direction of soil is along the passage with good connectivity, therefore the permeability is controlled by these passages. The seepage velocity in such channels is faster than in bad connectivity channels. Even if the channel has larger pores, the seepage velocity is still small. INTRODUCTIONUnderstanding the seepage mechanism in porous materials is significant in both theoretical and engineering problems. As a typical porous media, soil consists of solid particles and voids, which form connected channels allowing water to flow through. Such seepage in soil exists widely among geotechnical project of slope, foundation pit, and tunnel, etc. Meanwhile, a number of engineering accidents are caused by limited knowledge of seepage characters in soil (Huang, 2006; Liu, 2013). The conventional method in describing seepage features mostly based on the parameter of permeability, which is a macro statistic mean evaluating the whole connectivity of soil. Obviously, this parameter cannot exactly reflect the details of how water flows through the inner soil structure, especially the flow velocity in local mesoscopic area, hence is unable to represent the actual seepage properties. Therefore, it is necessary to develop mesoscopic approaches to fully study the seepage mechanisms."

Jan 1, 2015

By M. G. Lipsett

One challenge in applying information technologies in Mining is building a business case. In Mine Maintenance, there is a complex flow of information that contributes to making informed business decisions. By understanding those information relationships and the cost of wrong decisions, analysts can estimate the value of information flow. Developers can then ensure that systems deliver key information in an accurate and timely way. In this paper, general maintenance decision-making is discussed, with examples of how model-based analysis can improve the information delivered to decision makers.

May 1, 2001

By J. A. Chamberlain

DURING a recent trip across Canada and parts of the northern United States, the. writer examined some forty mine models. Construction -details and the uses to which the models were being put were outlined in a report to Eldorado Mining and Refining, Limited, and a specific model was proposed on the basis of the Company's particular needs at their Beaverlodge operation. It was felt, however, that portions of the report would be of some value to anyone contemplating building a mine model. For this reason, a synopsis of some of the more important aspects of the problem is presented here, together with a suggested model type that appears to have wide application. Thanks are due not only to Eldorado for permission to publish the following material, but also to the many mine personnel across Canada who allowed the writer to examine their models and gave freely of their time in discussion.

Jan 1, 1958

By T. A. Lazier, C. S. Longley

"Paymaster Consolidated Mines, Limited, owns several groups of claims in various parts of the Porcupine district. The area in which mining has been carried on includes parts of lots 5, 6, and 7, con. 1, Tisdale township, and twelve adjoining claims in Deloro township to the south. Highway No. 67A between South Porcupine and Timmins crosses the property.The discovery of the Dome mine in 1909 caused a rush of prospectors to the district and in a few weeks practically all territory adjacent to the Dome was staked. At that time work was started on the West Dome, West Dome Lake, Apex, and Standard properties. These were consolidated in 1930 to form the present Company. Gold was produced from the West Dome Lake from 1915 to 1930, and from the Standard-Paymaster from 1922 to 1928. The total production of the previous and present companies from 1915 to November 30, 1946, has been 487,170 oz. gold and 149,342 oz. silver from 2,337,554 tons of ore."

Jan 1, 1954

By M. A. Marois

This paper proposes an improved temporal stability condition for the implementation of an inverse heat transfer method for predicting the time-varying bank thickness of the phase change protective bank inside a high temperature furnace. The direct problem is handled with the enthalpy method. The inverse method rests on the Adjoint Problem and the Conjugate Gradient Method. It is shown that the temporal stability condition for the inverse phase change problem relies on the time delay of the temperature measurements. Results indicate that this time delay is proportional to the heat diffusion time including heat diffusion through the mushy zone.

Jan 1, 2011

By S. G. Shabestari

Thermal analysis is a tool that is generally employed to predict the structure of the alloy before the actual casting is carried out. By cooling a sample of the molten alloy and recording the temperature-time curve, important solidification events may be analyzed by using the first derivative-cooling curve. In this research, strontium is added to (AS5U3G) 319 aluminum alloy and its influence on the formation of intermetallic compounds e.g. Al15(Mn,Fe)3Si2, Al2Cu, Al5Mg8Cu2Si6 formed during pre- and post-eutectic reaction have been investigated. Also any changes in solidification parameters such as temperature of Al-Si eutectic under cooling and temperatures of nucleation and growth of each phases caused by strontium addition, have been determined via the first derivative cooling curves. The effect of strontium on the formation of various intermetallic compounds has been studied by using very accurate thermal analysis equipment and the microstructures were analyzed using an optical microscope. The various phases reported in this paper were identified using Scanning Electron Microscopy (SEM) and linked to Energy Dispersive Spectroscopy (EDS). Formation of all pre- and post-eutectic phases was interpreted by comparing the phases formed in the microstructure and the reactions detected by using cooling curves. The results of this research indicate that thermal analysis technique can be used as an on-line process control in the production lines in aluminum casting industries.

Jan 1, 2004

By Kazutoshi Haga, Batnasan Altansukh, Atsushi Shibayama, Ryuji Oinuma

"Recently, the arsenic grade in copper ores has been increasing year by year. Arsenic bearing minerals (enargite (Cu3AsS4) and tennantite (Cu12As4S13)) coexist with typical copper minerals such as chalcopyrite (CuFeS2). The removal of arsenic from copper ores that contain relatively high arsenic content is essential due to its adverse impact on the environment and the resulting economic consequences. In this study, arsenic removal and dissolution behaviour of Cu and As from enargite (Cu3AsS4) were investigated using ferric sulphate (Fe2(SO4)3) solutions containing sodium chloride under high pressure oxidation conditions. The effects of numerous parameters including the concentration of Fe2(SO4)3 and NaCl, temperature, total pressure, leaching time and particle size were studied while other variables such as pulp density and stirring speed were fixed at 100 g/L and 750 rpm. The results showed that more than 60% of the copper was dissolved in a 0.1 M ferric sulphate solution under the high pressure oxidative conditions, whereas the leaching rate of arsenic was less than 20%. SEM observation revealed that elemental sulphur was deposited on the surface of enargite forming a passivation layer and the residue was agglomerated. Those phenomena may cause a decrease in the copper leaching rate. It was found that more than 80% of copper was dissolved in the ferric sulphate solution in the presence of 0.34 M sodium chloride under the conditions optimized, whereas the dissolution of arsenic in the mixture did not exceed 2%. XRD analysis of the solid residues from the leaching experiments used ferric sulphate and mixtures of ferric sulphate and sodium chloride showed arsenic to be present as scorodite (FeAsO4).INTRODUCTION In recent years, there has been an increase of the arsenic (As) content of copper ores due to the gradual depletion of high grade copper ores. In some copper deposits, arsenic occurs in the form of minerals such as enargite and tennantite. The removal of arsenic in ores containing copper is critical to the production of pure copper and the management of the environmental challenges caused by the smelting process. Due to the environmental risk caused by arsenic emission and the deteriorated quality of the copper product, smelting of enargite concentrates is not an effective method for the extraction of copper (Padilla et al., 2010; Safarzadeh et al., 2014; Long et al., 2012). Therefore, a number of studies have been carried out to develop arsenic removal technologies from copper ores using various methods such as hydrometallurgy (Curreli et al., 2009; Tongamp et al. 2010), pyrometallurgy (Dalewski., 1999; Padilla. et al, 2012) and bio-oxidation (Ehrlich, 1964; Sasaki et al., 2010). Several hydrometallurgical leaching processes like sulphuric acid, alkaline sodium sulphide and sodium sulphate and ferric sulphate leaching have been developed to treat enargite ores and concentrates. The alkaline sodium sulphide leaching process has been developed for the removal of arsenic from enargite (Anderson, & Twidwell, 2008; Parada et al., 2014). The mechanism of the dissolution of arsenic from enargite in sodium sulphite solution is"

Jan 1, 2016

By F. M. Waldie

THE 2,538-foot belt conveyor recently installed underground at the Sullivan mine hoists ore from the 3,350-foot level to the 3,900-foot or main haulage level, a vertical distance of 680 feet. The design and planning of development work, under the direction of Mr. R. H. Stewart, Consulting Engineer, was begun in the spring of 1941. Development work was started in July of that year from the 3,350-foot level, and headings were started on the 3,650-foot and 3,900-foot levels later in the same year. It was the intention at that time to keep three headings going on development work necessary for the installation of the system: two on the conveyor incline, and one on the 3,900-foot level. This programme was modified in 1942 when there was some doubt whether the material for construction could be obtained. This problem of supply was eventually solved and the development work was pushed to completion in December, 1943. Construction was started in December, 1943, "'under the supervision of Mr. G. H. McKay, Superintendent of Construction and? Maintenance, and was completed in November, 1944.

Jan 1, 1945

By Franc R. Joubin, Donald H. James

"The Property of Rix Athabasca Uranium Mines Limited is in the Beaverlodge area of northwestern Saskatchewan. The mine is 7 miles by road north from the Lake Athabasca port of Bushell which is 250 miles north by aircraft or boat from railhead at Waterways, Alberta.The Rix property is a portion of the former DD 1 concession, obtained in 1949 from the government of Saskatchewan when private prospecting for uranium became permissible. The concession was prospected in detail during the 1950 and 1951 field seasons and a great many radioactive show-ings were discovered. Development and drilling were concentrated in two and later three of these areas, and by late 1952 enough ore had been indicated in the Leonard series and ""Smitty"" zone to justify underground development by adit-drift and shaft respectively.Four hundred feet of drift development on the Leonard No. 1 vein and the sinking of a two-level vertical shaft with related lateral development on the Smitty zone were completed in 1953. In April 1954 the Smitty section was placed in production at a rate averaging 100 tons per day, thereupon becoming the first privately owned post-war uranium producer in Canada. The ore is shipped for processing 12 miles by truck to the mill of Eldorado Mining and Refining Limited.Until recently all of the Company's production was drawn from the Smitty orebody. In April, 1955, ore production commenced from the faulted west extension of the Smitty structure, known as the Rix 62 zone, and from the Leonard No. 1 vein.The Smitty orebody (see Figure 2) is an intensely brecciated lenticular zone bordering both sides of the Smitty fault. The breccia areas are irregularly mineralized with pitchblende, very sparse galena, and pyrite in a gangue of feldspar, chlorite, calcite, and silica, all thoroughly soaked with fine-grained hematite to produce the locally-called ""red alteration"".Tenor of the ore currently being mined is classified information. The average grade estimated, prior to production, was 0.20 per cent (4.0 lbs.) U308 per ton."

Jan 1, 1949

By D. W. Li

Due to the ultrasonic testing and mechanical wind speed sensor have high requirement for the environmental of the coal mine, the charge induction wind speed detection method based on wavelet analysis is proposed. The same wavelet disturbance detection method is used at a fixed distance to obtain an induction signal to obtain a pass time, and then calculate the magnitude and speed of the wind. Simulation and verification experiments show that the method has application across a wide range of test speeds (up to 60 m/s). The metal probe causes little pipeline flow field interference. The method is particularly well-suited to dusty environment, and does not cause dust deposition through long-term operation. It can be widely used in coal mines for point wind speed continuous online testing.

Aug 1, 2013

By J. M. Carr

The history, geological setting and local geology of the Magnum vein system, 100 miles west of Fort Nelson in northeastern British Columbia, are described. The system comprises a number of quartz-ankerite veins, mineralized with chalcopyrite and lesser pyrite, occurring in a steep northeastly zone of deformation and subsequent dike intrusion within otherwise little-deformed Precambrian sedimentary rocks. In April of 1970, Churchill Copper Corporation began producing copper concentrates in a 750-tpd mill fed from the Magnum mine.

Jan 1, 1971

By DON E. MacDONALD

Marl in Alberta is confined to highly specific geological, hydrogeologica/ and climatic settings. Tufa is fa irly abundant in those areas of western Alberta where bedrock is of the Paskapoo Formation. Marl and tufa originate when the following conditions are met: presence of a carbonate source in drift or nearsurface bedrock; leaching of the carbonate by percolating groundwater; transportation of calcium and bicarbonate ions in a permeable aquifer; discharge at the surface as springs, seeps or lakes; re-precipitation of calcium carbonate. Alberta has seven categories of marl and tufa deposits, based upon over-all depositional environment and calcium carbonate

Jan 1, 1984

By P. Maltais

Over the last 10 years, Computer Aided Design, Finite Elements Analysis and field testing of prototypes have enabled the cycling industry to grow and to significantly improve its products. However, today's cyclists have become more and more demanding, making these classical design approaches almost obsolete. Devinci understood that problem four years ago and fully revisited its design approach; to offer bicycle frames better suited to real life riding, one must fully know those real life conditions. In partnership with the University de Sherbrooke, Quebec, Canada, Devinci then developed a bicycle enabling them to measure the actual load applied on a bicycle frame in real-time for real riding conditions: the instrumented bike. Today, Devinci uses its instrumented road and mountain bikes, combined with virtual prototyping and laboratory testing capabilities to develop better bicycles, faster.

Jan 1, 2006

By D. Mills, W. J. Brantina

"Mechanical and magnetic characteristics of ferromagnetic materials were investigated by a pulsed ultra-sonic technique. Two instruments, the Ultrasonic Attenuation Comparator (Sperry) and the standard type Reflectoscope (Sperry) were used for measurements of the attenuation of the ultrasonic pulse. The effects of elastic tensile and compressive stresses on the attenuation of annealed and cold worked material are described. In addition, the effects of plastic de-formation, relaxation and aging processes and different ultrasonic test frequencies are reported. The results for Armco iron, SAE 1020 steel, SAE 4340 steel and AISI 420 stainless steel are shown. Under the test conditions, the attenuation was found to be largely a sum of two components; a ""dislocation"" component associated with the losses accompanying the oscillations of dislocation line segments and a ""ferromagnetic"" component associated with the microeddy currents generated by magnetic domain wall oscillations. Either of these components might be dominant depending on the nature of the particular specimen and the test conditions. Finally, the possibilities of using ultrasonics in residual stress determinations, in fatigue studies and in the study of the ductile-brittle transition in ferrous materials, are briefly discussed."

Jan 1, 1960

By E. Mataradze

Statistics shows that the majority of accidents with fatal outcome are caused by methane and/or coal dust explosion. This leads to assume that contemporary counter-explosion systems of various designs cannot be considered effective. Considering the growing threat of methane explosion in the coming years along with the development of deeper levels, the improvement of a system for protecting people in underground opening appears urgent. This paper presents the results of the testing of the Automatic System from Methane Explosion in Coal Mines. The protective system consists of: i) a wireless device for the detection of explosions and activation of a protective system, and ii) an absorber with a pyrotechnic device ensuring the discharge of dispersed water. The protective system, at the command of the initiation signal, produces tailored dispersing water mist with droplet sizes in the range of 25?400 ?m along selected tunnel sections.

Aug 1, 2013

By F. Richards

"The property of the Cariboo Gold Quartz Mining Company; Limited; is in the Wells-Barkerville district of Cariboo mining division. It consists of a group of 106 Crown granted mineral claims and fractions; and extends for over 6 miles along what is termed the Barkerville gold belt. The main portal and mine camp are half a mile south of Wells; which lies at the northeast end of Jack of Clubs lake and is reached by a 55-mile motor road from Quesnel; the northern terminus of the Pacific Great Eastern railway.Gold-bearing quartz veins were discovered on the surface in various parts of the property by different prospectors as far back as 1877, but the work that led to the formation of the present company was performed by Al Sanders in the year 1926. Sanders dug trenches and drove small adits on quartz veins containing gold above what is now known as the Sanders zone. Very little underground work has been done beneath the earliest known discovery-the B.C. vein. The Cariboo Gold Quartz Mining Company was formed in the autumn of 1926. The total production of gold from its beginning in 1933 to the end of 1944 has been as follows:"

Jan 1, 1954

By R. J. Fruehan

Oxygen steelmaking (OSM) is not only the dominant steelmaking process but defines the structure of the industry. There are a number of myths regarding the future of OSM, which are false. These myths include that the EAF will become the dominant process in the near future, it is less costly to produce steel in an EAF and OSM is a mature technology and no new developments are occurring. These myths are shown to be false. Selected new developments are discussed such as post combustion, recycling of waste oxides, slag splashing and sensors.

Jan 1, 2004

1. Scientific prospecting has had a profound and some-what unexpected effect on the world's supply of raw materials over the past twenty years. Where shortages were recently anticipated, abundance now prevails. It seems probable that, for the foreseeable future, adequate metallic resources will be found at costs well within the world's economic means. 2. The amount of research devoted to scientific prospecting has been extremely small in relation to the possible importance of the problem and to what could be done. It has been dominated by the thought of a dozen brilliant men, and true research expenditures have not amounted to more than a few million dollars. 3. An undue proportion of the expenditures have been for so-called geological research -mostly of a petrologial character. The results have essentially been of historic interest only. However, there has been some in-crease in genetic understanding, and this is of great importance for future resources. 4. Basic advances in mineral exploration have been made in detection techniques, generally called geophysics and geochemistry.

Jan 1, 1964

By C. J. Sullivan

Many metalliferous ?provinces are co-extensive with particular groups of sedimentary, volcanic, or :basic plutonic rocks. Deposits may be truly syngenetic (Rand, Rhodesia-Katanga, Mans-field, Blind River, White Pine); re-. concentrated by circulating waters (Colorado Plateau, Red Bed Coppers) ; or re-concentrated thermally during metamorphism and granitization (most uranium and lead-zinc provinces ?and some copper and gold provinces). Basalts may yield important cop-per provinces when folded and re-heated. Granitization of basalts which have not reached the chlorite-carbon-ate phase of metamorphism may produce copper provinces. If they reach ?the chlorite-carbonate stage, granitization may result in a gold province. Copper and copper-nickel provinces may result if gabbros are granitized, and a ?similar alteration of per-idotite may result in asbestos or nickel ores. Many similar associations are known. Granite is not a source of ore, but a result of heat. A classification of ?ore with respect to source rocks is of greater prospecting value than are classifications based on magmatic differentiation and hydrother-mal solution theories. Volcanic centres are important ore foci because the thermally unstable metallic sulphides may be concentrated here by a distillation process. The ores found in the hot spring deposits, viz., mercury, mercury sulphide, sulphur, and the compounds of ?antimony and arsenic, are not those which are soluble in water at low temperature (epithermal sub-division of hydrothermal class), abrut those which are unstable thermally at comparatively low temperatures . Water is one of the most common thermally unstable minerals, and generally accompanies the thermally activated ore-forming sulphides.

Jan 1, 1957

By Perry L. Christian

"Mana/ta Coal Ltd. 's Costello Mine, located seven kilometres east of Estevan, Saskatchewan, has been operating at the present location since 1960. During the past twenty-three years, annual production of lignite coal has averaged 590 000 tonnes. The coal is used for power generation and for industrial and domestic use. Markets, operating techniques, facilities in place and reclamation are discussed. Introduction The Costello Mine (formerly the Klimax Mine) is located in southeastern Saskatchewan, approximately 210 kilometres southeast of Regina and 5 kilometres from the United States' border, as shown in Figure 1. The present mine, 7 kilometres east of the city of Estevan, has been operating since 1960. The history, however, of the Costello Mine and of the Estevan Coalfield dates from the initial settling of the area in the 1880s. Mining initially consisted of burrowing into the side of the Souris River Valley or other hillsides where the coal seam was exposed. Eventually, slopes were put down in the Estevan/Bienfait area and vigorous underground activity existed. In the late 1920s surface strip mining was introduced. The use of strip mining progressed to the point where it completely replaced underground mining in the 1950s and it is the only method in use today. During the past 23 years annual production has averaged 590 000 tonnes. The lowest production was in 1960 when the mine was starting up at 167 000 tonnes and the highest production was in 1977 when production was 1 509 000 tonnes. The Costello Mine controls approximately 11 400 hectares of mineral rights in the Estevan area. This is made up of 4 900 hectares of freehold coal and 6 500 hectares of leases. The area forms a large, irregular shaped configuration. Most holdings are contiguous and adjacent. The mine also owns some 8 400 hectares of surface rights. The lands under the Costello Mine's surface rights control, which are not being used in the mining operation, are leased to local farmers and ranchers. This ensures that the land is used to its full potential, both before and after mining."

Jan 1, 1985