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By T. B. Armstrong

"The energy situation is extremely fragile and there is a critical need for energy conservation in the short term and development of new technology in the long term. To keep tabs on energy flow, separate electrical metering is being installed in major industries: The first step reduces demand through peak load control; the second reduces the waste of energy by monitoring energy used per unit of production. IntroductionThe current energy situation is best described as being extremely fragile. The supply of hydrocarbons is being exhausted, while energy needs remain the same in the industrialized nations and are increasing in the Third World.The petroleum era is expected to come to an end in this century, as there will no longer be enough. Gas, coal and electricity will replace some oil as it becomes scarcer during the transitional period before new sources are gradually developed.There is a critical need for energy conservation in the short term. Conservation will, to a great extent be justified by savings, as it will be less expensive to recover energy that is being wasted than to acquire additional energy.The gradual development of new technology is expected to increase energy self-sufficiency in the long term. New energy sources are attracting a growing interest and are becoming more economically feasible and marketable. These rediscovered energy sources include peat, wood, solar, domestic waste and windmills.The sudden increase in energy prices has forced users to look at the way energy is used and find ways to save it. Major industries have found that using separate meters for each department spurs energy responsibility. Energy trim programs now rank in importance with profitability, productivity and with quality.Energy has become such a crucial cost element that better data are essential for planning. Data acquisition varies with plant size and number of utilities. Meters can be read manually or monitored by computerized energy management systems.The relationship of electrical energy input and production levels for a typical uranium mine will be used to demonstrate two steps to energy management. The first step reduces demand through peak load control; the second reduces the waste of energy by monitoring energy used per unit of production.The direct benefit of saving energy is the money saved."

Jan 1, 1980

By Neil Campbell

"The Pine Point area is on the south shore of Great Slave Lake, 510 air miles north of Edmonton and J JO miles south of Yellowknife, N.W.T. The occurrence there of lead and zinc was reported in J 899 by R. Bell (5) of the Geological Survey of Canada, and in the following years several claims were staked and some prospecting was done. In 1928 Atlas Exploration Co. took over the property containing the discovery occurrences. In 1929 The Consolidated Mining and Smelting Company of Canada Ltd. (""Cominco"") and Ventures Ltd. participated with Atlas in forming the Northern Lead-Zinc Co., which, under the direction of J. M. Bell, carried out 24,499 feet of drilling in the discovery and surrounding areas. Two shafts and many surface pits were also sunk. This work showed that the discovery deposits contain about 500,000 tons of lead-zinc ore, but no new orebody was found.In 1936 D. F. Kidd (11) drew attention to the highly significant space relations between the base-metal discoveries at Pine Point and the projections of certain major Precambrian faults mapped earlier by C. H. Stockwell. Geological work by Cominco in 1940 and subsequent years suggested the presence of mineable deposits within a belt of land including part of the area of earlier field work and extending far beyond it. Between 1946 and 1954 exploration financed by Cominco and Ventures Ltd. included 182,950 feet of diamond drilling, 383 feet of sinking, and 240 feet of drifting, raising, and crosscutting. This work was successful in finding substantial quantities of new ore in places where bedrock is completely concealed.The topography is one of low relief, characterized in many places by swampy muskeg and shallow, marl-bottomed ponds. The area where ore has been found is generally higher ground which, though not well drained, is comparatively dry. It is also marked by raised beaches and a few sand dunes overgrown by small spruce and pine. Bedrock is generally overlain by a variable thickness of hard, glacial boulder clay. This in turn is covered by silt, sand, and gravel, probably deposited from the waters of Great Slave Lake, which formerly extended many miles beyond its present southern shore."

Jan 1, 1949

By C. G. Anderson

As the global demand for copper and gold steadily increases and the need for environmentally sound processing also grows, successful hydrometallurgical treatment of enargite (Cu3AsS4) concentrates has come to the forefront. This type of concentrate contains considerable arsenic so that successful arsenic fixation, for example as scorodite, is of the essence. This paper outlines the successful application of low temperature and low pressure nitrogen species catalyzed (NSC) hydrometallurgical pressure oxidation of enargite concentrates. The successful stabilization of the arsenic as an iron arsenate compound is discussed. Also, the use of experimental design software is highlighted as a process application and optimization tool.

Jan 1, 2006

By Frank Lemy

This paper presents an application of digital face mapping in an underground mine. Based on photographs it was possible to construct discontinuity maps, which were used to characterise the rock mass. The results were compared favourably with values obtained through scanline and area sampling mapping for the same site. The case is made for digital mapping as a safe, fast, and efficient way to characterise rock mass structure for engineering purposes.

May 1, 2001

In order to avoid impurity problem and enhance absorption/desorption kinetics of Mg-based compounds, nanostructured Mg-based compounds were synthesized from Mg, Ni and other elemental nanoparticles produced by hydrogen plasma-metal reaction. XRD and TEM results demonstrate that homogeneous nanostructured Mg-based compounds with less impurity were successfully synthesized by this method. DSC in hydrogen atmosphere, pressure-composition isotherm and the kinetics of hydrogen adsorption/desorption were investigated at different temperatures. The results show that the nanostructured Mg-based compounds can absorb hydrogen in a high speed at a low temperature.

Jan 1, 2005

The University of New South Wales (UNSW) has been a world leader in the development of innovative virtual reality technologies over the last 10 to 15 years. These developments have included developing the world?s first 360° surround, virtual reality (VR), stereo projection theatre system known as AVIE (Advanced Visualisation and Interactive Environment), which was developed by iCinema, a collaborative venture between the UNSW Faculties of Engineering and College of Fine Arts. The UNSW School of Mining Engineering has been responsible for development of mining applications virtual reality software modules and to date, has developed eighteen different mine safety training and mining engineering education modules which run in the AVIE environment. This platform and technology package provides a unique ?immersive environment? experience for groups of trainees or students who can engage with the simulated environment in the complete safety of the virtual reality theatre. In all of the major international mining industries, safety is of paramount importance, and training of personnel is an essential component of any comprehensive proactive safety management system. All personnel need to be aware of the inevitable hazards around them at all times, as well as understand appropriate safety and operational procedures. This can be done by conventional class-room style training sessions, or by provision of training documentation. However the effectiveness of such systems is often very limited due to the inability of trainers to engage with the audience for a lengthy period of time; or to convey the often complex and variable mining environments and situations which can exist in a typical mine. The ability to immerse the trainees in a virtual mine environment, with all the reality of an actual mine but with none of the physical exposure to actual hazards, provides a far more effective and engaging training experience. Furthermore, in the virtual world, trainees can be exposed to the very unlikely, but nevertheless high consequence hazards such as mine fires, falls of ground or outbursts, without any risk to their safety and well-being. The end result is that trainees will be far more engaged with the learning environment they find themselves in, and will develop a far higher level of understanding of the topics, rather than simply experiencing a passive class-room style learning environment offered by conventional training modes. The UNSW systems have been implemented widely within the Australian mining industry and the mining engineering education sector and are now being adopted internationally. This paper presents an overview of the innovative technologies involved in these virtual reality systems ? as applied to the mining industry. Modules developed for both mineworker training and mining engineering student learning will be presented, to illustrate the effectiveness and value of such a training and education approach.

Aug 1, 2013

By Tatsuya Oki

Tantalum capacitors can be found mounted on printed circuit boards of domestic appliances such as personal computers. These capacitors contain a considerable quantity of expensive metal tantalum and can be detached and liberated from printed circuit boards by impact breakers. In this study, the size and density distribution of the liberated electronic devices were investigated. Then, tantalum capacitors were recovered from other electronic devices using size separation and pneumatic gravity concentration methods. More than 70% of Newton's separation efficiency was obtained for tantalum capacitors. High Newton's separation efficiency could be also obtained for other types of electronic devices such as chip resistors.

Jan 1, 2011

By G. Bonnivard

"A complete laboratory process for the treatment of lateritic ores containing a high proportion of iron, as well as chrome and alumina, has been established. The ores treated originate from the tropical zones and result from superficial climatic alteration. According to recent estimates, the known reserves of such ores reach many billions of tons, thus representing huge potential reserves for the elements they contain.The process used is based on the alkaline roasting of pelletized ore in the presence of sodium carbonate. This treatment results in the separate recovery of pellets of upgraded iron ore, pure chrome oxide and hydrated alumina. The research described in the paper aims at determining the best experimental conditions for obtaining the highest extraction of the required oxide from this type of ore."

Jan 1, 1967

By Paul J. Beck

The impact of mining development on the environment can be minimized through comp careful construction and accurate monitoring. Key to meeting these objectives is t information at all stages of design, development, operation and decommissioning. This paper will describe cost-effective means of gathering and managing reliable fiel groundwater flow and surface water regime within and surrounding the mine site, as localized contaminant plumes associated with mine operations, and monitoring ground quality. Recent research has led to the development of inexpensive, easy to install syst sampling/monitoring from different zones within a single borehole. Advances in elect developed small diameter probes and pumps for measuring water levels and taking wat continuous monitoring stations in remote areas can be colldeacttaeldo gaguetrosm aatnidc adlolwyn luosaidnegd from a central facility using telemetry systems powered by direct, battery or solar radio frequency, landline or cellular telephones, and satellite. Two case studies will illustrate the use of datalolgagregres sacnadl et eblaesmient rwyi dien mao nitoring sc and the use of multilevel samplers for managing a contaminant plume.

May 1, 2004

By T. Crivits

"Phase equilibria in the ‘Cu2O’-‘Fe2O3’-SiO2 system, the base slag system in copper production, were recently determined. However, the addition of MgO, commonly present in the slag, drastically changes the phase equilibria in this system. The present study focuses on the phase equilibria in the ‘Cu2O’-‘Fe2O3’-MgO-SiO2 system in equilibrium with metallic copper.Recently, an experimental procedure has been developed that resolved a number of experimental difficulties. This procedure has been successfully applied to characterise several complex industrial copper slags. It includes a high-temperature equilibration followed by rapid quenching and electron probe X-ray micro-analysis (EPMA). The methodology was adapted to the present system and used to determine the liquidus at SiO2 saturation and in contact with high-MgO phases in between 1100 and 1250 °C in Cu2Orich slags.The results indicate a maximum solubility of MgO in the system at 1200 °C of 5 wt%. The boundary line between tridymite and spinel lies 3-4 wt% closer to the SiO2 apex for every 2 wt% MgO added. These new data on the high-copper slags are important for optimisation of the direct-to blister"

Jan 1, 2014

By W. R. Hopkins, J. A. Davis

"This paper presents a discussion of the mechanisms by which aerosols of the process electrolyte are entrained into the breathing environment of copper, Zinc and nickel eIectrowinning tankhouses. Literature outlining the health effects associated with worker & posure to the acidic and metallic contaminants found in the airbome aerosols is summarized and compared with existing North American regulations.A brief review of the existing technologies for the source reduction of these aerosols is presented. This paper outlines the industry experience with use of covers, balls, beads, shapes, fixtures and chemical surfaetants. Each of these devices is ranked according to its effusiveness in the process in which it is used, and rated according to its operator acceptance.The various forms of existing in-plant ventilation systems are reviewed with a discussion of their relative merits and effectiveness. Actual experience is related, detailing the methods of testing for ambient contaminant levels in a variety of tankhouse environments. Guidelines are provided for the site and process specific criteria which govern the selection and ultimate effectiveness of a particular form of ventilation system.Finally, actual project experience is cited in which hydraulic modelling is used a design tool in tankhouse ventilation design. These projects include the upgrading of existing traditional ventilation designs, and the ''grass roots"" design of a more efficient aerosol source control system to be used in high altitude, cold weather sites."

Jan 1, 1994

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

By E. Nejati, S. Khoshkooei, V. Firouzdor, M. Akbari, F. Khomamizadeh

In this study the effects of Si content on mechanical and thermal fatigue properties of Al-Si casting alloys were investigated. Repeated heating and cooling cycles were applied on the samples at 230°C to develop thermal fatigue cracks. Crack growth mechanisms and microstructural influences were investigated by optical and scanning electron microscopy. Thermal fatigue behaviors were improved successively by increasing of silicon content up to 7wt%. However, addition of more than 9wt% silicon decreased the thermal shock resistance of the alloy. Silicon contents of about 9wt% presented the best mechanical and thermal fatigue resistance in the alloy.

Jan 1, 2006

By S. G. Shabestari

In the metal casting industry an improvement of component quality mainly depends on better control over the production parameters. Thus, thermal analysis cooling curve of the alloy is used for process control in aluminum casting industry. Cooling rates of the alloy during solidification process affect microstructure, grain size, eutectic silicon morphology, and dendrite arm spacing (DAS). In this research, effect of cooling rate on the microstructure and solidification parameters of 319 aluminum alloy that is a widely used alloy in automotive industry, has been investigated by means of thermal analysis. Seven different cooling rates have been obtained by using CO2-bonded silica sand molds with two different wall thicknesses, hot-work tool steel molds (H13) with and without coating, thin-wall steel molds with different coatings. In each case, cooling curve and first derivative cooling curve have been plotted by use of very accurate thermal analysis equipment. Effect of different cooling rates on solidification parameters e.g. Nucleation temperature (TN,a), nucleation undercooling (ATN,a), recalescence temperature (TR,a), solidification range (AT,s), and total solidification time (t 0 have been studied in the liquidus region. Microstructural evaluation has been carried out and DAS were measured in all solidification conditions. A numerical equation was proposed to predict cooling rates via measuring DAS in 319 aluminum alloy. Nucleation process and the effect of cooling rate have been interpreted by using thermal analysis cooling curves and microstructural study.

Jan 1, 2004

By N. Geoffroy, E. Benguerel, G. P. Demopoulos

In the late 1990s, a chemical process to remove mercury and selenium from weak sulphuric acid solutions was patented and implemented in the CEZinc refinery in Valleyfield, Quebec. The CEZinc process comprises two stages. In the first one, sodium sulphide is added to the weak acid solution in order to precipitate the soluble mercury. The solution is then treated with sodium dithionite in order to reduce the selenium to elemental form. Because of recent changes in the composition of the industrial solution, a project to study the background chemical reactions was started. In this paper, a review of the background chemistry is presented on the basis of several eh-pH diagrams on one hand, while on the other experimental results are reported dealing with the reaction of selenium (IV) species with either dithionite, sulphide or a combination of the two. According to this work, elemental selenium enjoys a wide pH-eh range stability with selenium sulphide being metastable. Selenium (IV) in single metal synthetic solutions was found to be reduced - to elemental state - at ambient temperature down to ppb range with dithionite as long as the stoichiometric ratio (dithionite/selenium) was in excess of two and the pH < 1.7. Under these conditions the reaction was very fast reaching completion within one minute. Sodium sulphide proved equally effective in reducing selenium (this time as selenium sulphide) to ppb range from single metal solutions. However, in mixed Se-Hg solutions deviations from this "ideal" behaviour was observed resulting in higher levels of residual soluble selenium left in solution.

Jan 1, 2008

By V. K. Karra

"A simplistic algorithm jar simulating the rod or ball mill Bond grindability test applied to ores and minerals is presented. A performance comparison between the present algorithm and a previously published algorithm by Kapurot, modified in this work jar a fair evaluation, is also given. A worked example is furnished jar leading the reader through the various calculations.IntroductionThe Bond grindability test is widely used for the prediction of the power requirement of an industrial grinding mill. The procedures for conducting this test in either a ball or a rod mill are available(1). In the case of a ball mill, batch grind abilities have been correlated to Bond grindabilities to help monitor day-today variations in ore grindability for the purpose of plant control( 2,3). Of special interest is the algorithm presented by Kapur(3) for the simulation of the Bond test. In practice, the test lasts from 6 to 14 cycles (4 to 10 hours). With this algorithm, one can predict the Bond grind ability using information available from only the first two cycles.Sometimes the prepared feed for the grindability test contains too much fines compared to the total product desired at the mesh of grind under consideration. In such a case, the operator separates the fines from the test feed and adds to the remaining coarse fraction an equal amount of fresh feed. This combined feed then forms the feed to the first cycle of the test. In the present work, Kapur&apos;s algorithm is modified to include this special case. A new and relatively simpler algorithm is also presented. Statistical equations relating work index to pertinent variables are also given."

Jan 1, 1981

By P. D. Duever, P. J. Readyhough, P. L. Silveston

"The Plastojrost apparatus, developed by Ritter and Juranek in the 1960s has been modified primarily, to automatic temperature control. A limited investigation of carboniferous and cretaceous coal samples showed that both coals undergo the same changes when coked in the Plastofrost unit. Dilatometer plastic range and total dilatation correlated well with the Piastofrost plastic range for the carboniferous Appalachian coal, but not for the cretaceous western Canadian coal. Work to elucidate the characteristics of some western Canadian coals using the Plastofrost is in progress. IntroductionCoke quality is critically affected by the properties of the plastic phase in the coal-to-coke transformation. Since these properties exist in a coke oven and are not measurable, they are approximated by standard laboratory tests, such as free swelling index, plastometry, and dilatometry. Of particular interest to us is the anomalous behaviour of western Canadian coals of cretaceous origin. By many predictive methods, these coals should not produce coherent cokes. When coked in pilot scale test ovens, in fact, they produce cokes of good stability. They typically make up 20% of Japanese coking coal blends and are also used in South Korea, Mexico, Brazil, and several European countries. This anomalous behaviour has been studied in our laboratory<8.9.1O). Plastic properties or rheological tests examine just the external ramifications of the coal-to-coke transformation. To understand the process, however, microscopic examination of the coal and coke seems to be needed. The Plastofrost unit has been shown to be a convenient means to this end."

Jan 1, 1987

The 2-4D window shown above is the base startup window which allows you to begin a new project. ??Setting up the project is the first step ??The next step is to setup the properties to be used in this project

Feb 1, 2008

By Georges Houlachi, Akram Alfantazi, Michael Mahon, Maysam Mohammadi

Corrosion resistance of the lead-based anodes directly influences the purity of the final product in the zinc electrowinning process. The anodic MnO2 layer that is electrodeposited on the anodes during this process can protect the anodes against corrosion. Sand-blasted anodes generate a uniform, adherent and shiny MnO2 layer, which gradually blisters and eventually sloughs off after several weeks. In this study, we attempted to develop a new method to stabilize the MnO2 protective layer on the anodes during the electrowinning process by providing suitable nucleation sites for electrodeposition of this layer. MnO2 particles (P80=40µm) were used as seed material for this purpose. Different techniques of galvanostatic and cyclic voltammetry polarizations, scanning electron microscopy (SEM) and atomic absorption spectroscopy (AAS) were employed to investigate the performances of the MnO2-seeded lead anodes. The experimental results showed that growth of the MnO2 layer is influenced by the MnO2 seed particles on the anode surface. The MnO2 layers electrodeposited on the MnO2-seeded lead anodes were uniform and strongly adherent to the substrate. This layer was more stable than those formed on the PbAg anode without MnO2 seeding. This could provide the anode with a higher level of corrosion protection. Moreover, formation of undesirable MnO2 mud in the electrolyte and the rate of manganese consumption were decreased when the MnO2-seeded lead anodes were polarized. These observations could be attributed to the different properties of the electrodeposited MnO2 layer on this anode in comparison with that formed on the PbAg anode.

Jan 1, 2016

By X. Cao, J. J. Jonas, Wanjara. P., J. Gholipour, E. Dalgaard

The linear friction welding (LFW) behaviour of near-ß titanium alloy Ti-5Al-5V-5Mo-3Cr (Ti- 5553) was investigated. Microhardness measurements were performed in order to evaluate the mechanical properties of the welded material. The linear friction welded (LFWed) Ti-5553 was examined with optical microscopy and scanning electron microscopy (SEM) to evaluate the microstructure’s response to the thermomechanical conditions. Characterization of the welds included analysis of the microstructural features of the weld region and thermomechanically affected zone (TMAZ) in relation to the parent material.

Jan 1, 2010