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By A. Taylor

This paper considers mineral processing in zero gravity dry environments typical of asteroids or comets. The electro-dynamic separation technique using pneumatic flow systems is explored. Pneumatic delivery of solids is used because of extreme temperature changes and the possible scarcity of water. The present earth-based process and how it can be modified for these conditions is examined.

May 1, 2001

By I. C. Brown, J. F. Henderson

"IntroductionThe Yellowknife greenstone belt lies along the west side of Yellowknife bay on the north shore of Great Slave lake, some 600 miles north of Edmonton, Alberta. The producing gold mines along the belt include the Con-Rycon and Negus which came into production in 1938 and 1939, and the Giant Yellowknife, which followed in 1948. In addition to these, the Akaitcho and Crestaurum mines are potential producers and there are several promising prospects.Early geological work along the belt was done by A. W. Jolliffe who first recognized a number of great faults, the largest of which is the West Bay fault with a horizontal movement of more than 3 miles. In 1943, A. S. Dadson, following an examination of the Giant-Yellowknife property, advanced the hypothesis that Baker Creek valley was underlain by a series of major gold-bearing shear zones. Subsequent diamond drilling in 1944 bore out the correctness of this view and outlined the great ore-bearing shear zones that are now being developed and mined by Giant Yellowknife Gold Mines. Near the south boundary of the Giant property, the shear zones are cut off by the West Bay fault. This prompted Neil Campbell, District Geologist for the Consolidated Mining and Smelting Company, to make a detailed study of the geology along the West Bay fault in the hope of finding the faulted extension of the Giant shear-zone system on the west side of this fault. In this he was entirely successful. By careful geological mapping he matched several faulted diabase dykes on both sides of the fault and, knowing their dip, determined the horizontal and vertical components of movement along the fault. Subsequent •diamond drilling based on Campbell's work located the presumed correlative of the Giant shear-zone system on the Con-Rycon and Negus properties, where it has been named the Campbell zone or system. At the present time, all production at the Negus Mines property is coming from orebodies along the Campbell zone."

Jan 1, 1950

By Kurt Tischler

This paper presents the field experience of Siemens with regard to Gearless Drives in the mining industry ? We consider the elapsed production hours of Siemens Gearless Drives to be extensive enough to provide a reliable estimation of availability calculated on the basis of data representing repair time, downtime, and operating time. The users of Siemens Gearless Drives confirm an availability of more than 98% after exclusion of some major issues. The paper addresses all of these major issues of Siemens Gearless Drives, describes successfully applied corrective measures, explains the influences on the design of the drives, and lists the downtimes associated with each of these issues.

Jan 1, 2012

By K. R. Brown, P. L. Krawchuk

In-situ recovery (ISR) is under increased investigation as a viable methodology for the extraction of minerals in ore bodies that may be uneconomic to mine by traditional methods or for resources situated in locations where underground and surface mining operations are not feasible. Although the concept of ISR is relatively new with respect to hard rock applications, it is not a new technology; it has been used successfully in potash and uranium mining and also in heavy oil extraction for years where it has been proven to be both technically and commercially viable. ISR allows for the extraction of metals and minerals without the need to mine large amounts of ore that need to be processed at surface. The ore stays in-situ and only the valuable metals and minerals are produced to surface in a process that produces very little to no waste rock or tailings. This paper aims to discuss the geological conditions that make ISR amenable to an ore body as well as the application of maturing technologies such as advanced directional drilling and the creation of artificial permeability that will help to access deep ore bodies and enhance or create favorable recovery conditions for ISR in the ore body. INTRODUCTION In-situ recovery (ISR), also referred to as in-situ leaching, is a potentially disruptive technology for the mining industry. ISR is under increased investigation as a viable methodology for the extraction of valuable minerals that may be uneconomic to mine by traditional methods or for deposits situated in locations where underground and surface mining operations are not feasible. Although the concept of ISR is relatively new with respect to hard rock applications, it is not a new technology; it has been used successfully in potash mining, uranium mining and also in heavy oil extraction for years where it has been proven to be both technically and commercially viable. Recently there has been increased interest in deploying ISR in hard rock applications due to a number of factors: the drive for environmental stewardship is stronger than ever, technological advances in drilling, blasting, and leaching are strengthening ISR economics, and a large inventory of ore bodies exists that are not feasible to mine or extract using conventional open pit or underground mining techniques. ISR allows for the extraction of valuable metals and minerals without the need to mine large amounts of ore that need to be processed at surface. The ore stays in-situ and only the valuable metals and minerals are produced to surface in solution via a recovery process that produces very little to no waste rock or tailings. Where the right conditions exist, the ISR process has a much smaller environmental footprint (Hiam-Galvez, 2018) and potentially much lower capital and operating costs than using conventional mining techniques.

Jan 1, 2019

By S. Markstrom

The Boliden AITIK copper mine is located 100 kilometres north of the Arctic Circle in northern Sweden. A pre-feasibility study was conducted in 2005 with the aim of increasing the capacity of the existing processing plant. After analysis, options to upgrade the existing plant were abandoned in favour of building a new processing plant, with higher capacity and therefore greater profitability. A new plant could be designed with greater flexibility to make potential future expansions easier. A feasibility study for a new 36 Mt/y processing plant including fully AG grinding circuits and flotation was completed in 2006. The project was approved by the Boliden board shortly thereafter. Construction started in the beginning of 2007 and was completed during 2009. Commissioning of the new plant was undertaken in the first half of 2010. The grinding circuit consists of two lines with each line consisting of a 22.5 MW AG mill and a 10 MW Pebble mill in closed circuit with a spiral classifier. The nominal production level is 2 200 t/h for each grinding line. This paper presents the start-up and operation of the grinding circuit.

Jan 1, 2012

By R. C. Gilmore

Underground longwall coal mining sections may develop explosive mixtures of methane-air in the mined-out gobs. If the panel are operated as bleederless or sealed gobs, progressive sealing along the gate roads as the longwall face retreats limits the flow of fresh air into the gob and thus deprives potentially explosive atmospheres of oxygen. In a project sponsored by the National Institute for Occupational Safety and Health (NIOSH), researchers at the Colorado School of Mines have used computational fluid dynamics (CFD) modelling to simulate the flow of gases in longwall gobs. Modelling indicates that targeted injection of nitrogen through the seals along the gate roads inbye the face can be used to control the size and location of methane and air clouds within the gob and to minimize or eliminate the explosion hazard resulting from the formation of flammable methane-air mixtures in longwall gobs.

Aug 1, 2013

By John S. Stevenson

Zeballos mining camp is on the west coast of Vancouver island; 195 nautical miles northwest from Victoria.; The spectacularly rich gold-bearing veins that made Zeballos an important; gold camp were found early in 1934. Small pockets of very coarse; gold had been found earlier under large boulders at the mouth of Spud; creek; and in the autumn of 1933 rich gold-quartz float was found near the; mouth of the creek. The rocky beds of the steep creeks entering Spud creek; were searched for its source and as a result the veins on the White Star property; were found. The Goldfield vein on the Spud Valley property was discovered; in 1935; and the No. 1 vein on the Privateer in 1936. In the general; prospecting activity that quickly followed; other veins were found; not; only in Spud creek but in other creeks draining into Zeballos river.

Jan 1, 1954

About Barrick Paste Backfill at Barrick Goldstrike Rodeo Paste Plant Cyclone Lab Testing Challenges and Lessons Learned Future Barrick Projects

May 1, 2013

By Reinis Sipols

AGENDA ? Introduction ? Definitions and Key features ? PEA - Preliminary Economic Assessments ? PFS ? Preliminary Fesibility Studies ? FS ? Feasibility Studies ? Costs and Risks ? Cash Flow, Economic Analysis and Reporting ? Recommendations for Improved FS accuracy INTRODUCTION ? The reporting of material information on mineral deposits has been governed by NI 43-101 legislation for almost a decade. ? The investment sector depends on the independent, professional QP to provide objective observations, comments and recommendations through all levels of geological, engineering and financial evaluation until a mine construction decision has been made.

May 1, 2013

By K. H. Kretzschmar, M. A. Smith

A brief review of the rapid growth of ACT in Western Canada is presented. It is remarked that this rap-id growth has been accompanied by a heterogeneous approach to design. A more rational and consistent approach is suggested, together with the assumptions on which this approach is based. The operating history of some existing installations is discussed briefly, and conditions necessary for the continued growth of ACT are outlined.

Jan 1, 1960

By F. Khomamizadeh

In this study the effect of solidification rate, T6 and T7 heat treatments on thermal fatigue resistance of A319 aluminum was investigated. Increasing of the solidification rate improved the thermal fatigue resistance of the alloy by refinement of the microstructure. The most sensible areas for thermal fatigue crack growth were the eutectic zones, T6 and T7 heat treatments improved the thermal fatigue resistance of the alloy by enhancing of the matrix resistance against the crack propagation. The slight reduction of the thermal fatigue resistance after T7 heat treatment is attributed to coarsening of the precipitates which reduces the matrix resistance.

Jan 1, 2005

By J. R. Rodda

Stainless steels are widely used to handle concentrated sulphuric acid (H2SO4) solutions produced in the manufacturing process, The majority of corrosion rate data published for stainless steel in product acid conditions is typically complied in tables or in iso-corrosion diagrams (iso-corrosion rates plotted as a function of temperature and H2SO4 concentration), without any reported consideration as to the accuracy and relevance of the method used to obtain the data, Given the characteristic potential cycling associated with the active-passive corrosion behaviour exhibited by stainless steel in hot, concentrated H2SO4, weight loss is considered to be a more reliable method than electrochemical measurements to measure corrosion rates, Consequently, an effort is made herein to demonstrate the accuracy and relevance of weight loss to determine laboratory corrosion rates in product acid conditions.

Jan 1, 2010

By F. P. Hassani, A. Hara, M. Momayez

To be competitive on the international market, the Canadian mining industry must reduce its costs, increase its productivity and maintain a high standard of safety. There is a great need today for improved methods that would allow the detection of geological structures in advance of mining to reduce dilution and the monitoring of underground structures to increase safety. This will facilitate planning for optimum exploitation of the mine and to increase production at lower costs. This paper discusses two examples of more efficient mine planning using new technologies such as Ground Probing Radar (GPR). In Kidd Creek mine, GPR technology was used at the 2500and 2600 levels to (1) monitor the stability of the sill pillar; (2) locate the presence of disseminated sulphide pockets in the sill pillar for extracting the mineral content; (3) monitor the stope backs and wall structures to evaluate the effect of on-time filling sequences; and (4)assess rockfill quality in terms of the presence of voids and fractures within the rockfilled areas. In the New Brunswick coal mine in Minto, GPR was used along with core log data to map and construct a 3D block of a section of the bench showing the relative position of different layers overlying the coal seam.

Jan 1, 1996

By Pierre Laliberté

L?utilisation de plusieurs nouvelles technologies et systèmes de contrôle visant des économies d?énergie dans une exploitation minière pourrait laisser croire qu?il suffit d?additionner les économies potentielles de chacune de ces technologies pour en évaluer l?économie totale. Une addition simpliste des pourcentages d?économie pourrait, dans certains cas, dépasser 100%, ce qui est évidemment totalement incohérent. Les LMSM-CANMET sont à réaliser une étude dont les résultats serviront à estimer l?influence de certaines technologies et systèmes de contrôle visant des économies d?énergie et à évaluer l?impact des unes sur les autres. En outre, un modèle de simulation est en cours de création afin d?évaluer les gains incrémentaux liés à l?application d?une série d?innovations dans une exploitation minière. La présentation fera le point sur l'état d'avancement du projet en plus de soumettre quelques exemples.

May 1, 2007

By R. Panchadhara, P. A. Gordon

"A non-local formulation of the classical continuum mechanics theory called peridynamics is used to study driven dynamic fractures in the near wellbore region. The controlled application of pressure on the inner walls of the borehole can create multiple fractures that initiate from the borehole and propagate radially outwards. The number of fractures and their final length is primarily controlled by the loading conditions and the in-situ stress state. It is the objective of this study to use a novel numerical technique called peridynamics to investigate: 1) the influence of loading conditions on the fracture pattern, and 2) the effect of in-situ stress anisotropy on fracture propagation. In peridynamics, the momentum equation from the classical theory of solid mechanics is replaced with the integro-differential momentum equation of peridynamics. As a result, discontinuities in the body, such as fractures, occur spontaneously. The material is represented by a continuum body with material points that interact non-locally with all other points within a specified distance. Fractures evolve using a damage evolution law, wherein, damage at any point is represented as the ratio of the number of broken bonds in the current configuration to the total number of bonds in the undeformed configuration.Simulations are performed on simplified test cases and the results are compared to relevant experimental and numerical studies found in the literature. It is shown that the loading rate significantly influences the number of fractures initiated from the borehole as well as their extent. Low loading rate produces fewer fractures, whereas, high loading rates produce longer and a greater number of fractures from the borehole. The numerical method successfully predicts the fracture pattern obtained from a wide range of loading conditions. Predictions also indicate that the resultant fractures are shorter when in-situ stress is applied. Numerical results show that the fracture extension is largest in the direction perpendicular to the minimum compressive stress for the range of loading rates used in this study."

Jan 1, 2015

By W M. Gilchrist

This paper gives an estimation of the future requirements of the western world in relation to energy re-sources. It then goes on to outline the role that atomic power -with its basic raw material, uranium -will play in supplying these energy requirements. Canada's position in this picture is covered, and some interesting forecasts are made. Introduction I T is possible that the following remarks will appear to have more to do with power than uranium. However, to fully comprehend what is in store for the Canadian uranium mining industry, we must be able to estimate the potential requirement, and, to do this satisfactorily, a thorough understanding of the circumstances that will give rise to that demand is necessary. The growing need for electrical energy will play by far the major role, as large tonnages of uranium will be required for its generation. The nuclear weapon has, up to the present, comprised the major market for uranium.

Jan 1, 1964

Waste rock extracted from a mine is typically stored nearby on the surface. Such waste rock piles must be designed to ensure their geotechnical and geochemical stability during the mine operation and after closure. The optimal construction of a pile requires detailed planning. Deposition should involve benches of limited height to control the global slope angle, based on the long term factor of safety. It can also be advantageous to compact the top of each bench and to give the surface an outward inclination to control water flow by limiting infiltration and favoring lateral diversion. When part of the waste rock contains reactive minerals, it is also deemed necessary to use selective placement with the non-reactive portion to prevent direct exposure to natural conditions. The construction must be well documented, and include data from the monitoring program. These and related aspects are presented and discussed in the paper.

Aug 1, 2013

By Ainul Akhtar, Steve Cockcroft, Daan Maijer, Carl Reilly, Lu Yao, Jun Ou

A coupled thermal-fluid flow-multicomponent model has been developed to aid in understanding the melting/dissolution behavior of solid Al-rich Material (TiAl) in a liquid titanium pool produced by an electron beam. The model is capable of accounting for the significant phenomena present affecting heat, mass and momentum transport including thermal and compositional buoyancy and Marangoni forces, Darcy attenuation, evaporation, melting and solidification, and the associated release or absorption of latent heat. The modeling results have indicated the compositional fluid flow driving forces (compositional buoyancy and Marangoni forces) contribute significantly to the melting/dissolution process. The model is waiting for validation against empirical data.

Jan 1, 2014

This work illustrates the potential of two welding processes for joining AA1100-16 vol.% B4C metal matrix composite: laser welding process using a 4 kW Nd:YAG laser and Friction Stir Welding. A comparison is made between these two welding techniques in terms of microstructure and mechanical properties of welded joints. A large amount of brittle needle-like phases, together with some residues of B4C particles were observed in the fusion zone of laser welded joints. The use of Ti filler can improve the microstructure and increase the joint efficiency from 63% to 75%. On the other hand, the friction stir welding process being a solid state welding technique is interesting as it avoids the formation of brittle intermetallic phases. In addition, the breakage of B4C particles and the grain refinement of the matrix were observed in the weld zone. Consequently, FSW joints show much better mechanical properties than laser welded joints. Up to 100% joint efficiency can be achieved by FSW for annealed AA1100-16 vol.% B4C materials.

Jan 1, 2011

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