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The Environmental Excellence in Exploration (E3) project is driven by the recognition that the minerals industry can only maintain its long term viability by ensuring its continued access to lands to explore for, and develop, new mines. Widespread implementation of sound environmental management practices by the exploration community and improved education and understanding of that by stakeholders will help substantially in accomplishing this, and E3 is designed to meet these needs. Exploration crews are now viewed as ambassadors for the global mining community. Their performance in managing the environmental aspects of an exploration program can demonstrate a commitment on the part of the international mining sector to environmentally responsible exploration and mining. We have all observed that failure to behave responsibly can alienate local residents, encourage anti-mining NGOs and jeopardize development. As the saying goes, ?you don?t get a second chance to make a first impression?, and we want to make a favourable first impression. The E3 project is focused on creating an electronic manual, the e-manual, which will provide rapid access to the most up-to-date information on environmental management practices for minerals exploration globally. The e-manual will reflect current thinking and practices in environmental management. It will be richly illustrated with actual examples that reflect the realities of exploration. It will strive to identify the key environmental issues and concerns that apply to most exploration projects, and identify other sources of relevant information useful to field practice. It is our belief that E3, or something very like it, is central to ensuring that the industry survives the current challenges to its viability. E3 will be a cornerstone of the mining industry?s drive to sustainability simply stated, if we are not permitted to explore for mines, there will be none of them at some point in the relatively near future.

May 1, 2002

By K. Thuro, L. Wilfing, H. Kasling

"In mechanized tunneling, performance prediction is a crucial issue for estimating excavation costs and construction time of a tunnel project. The aim of this work is to compare the calculated parameters by penetration prediction models with the results of penetration tests during excavation by a Tunnel Boring Machine (TBM) at actual tunnel projects. This comparison helps to improve the existing prediction models (Gehring, 1995 and Rostami (Colorado School of Mines), 1997.) and to develop a new, so-called “Alpine Model” (research group ABROCK; Schneider et al., 2012).On-site penetration tests are a common tool to determine performance of a TBM in certain geological environments. During a test, the TBM is operated under defined conditions that allow comparing the results of different projects and machine types. There are two different types of penetration tests in use. The more common type, described by Bruland (1998a), is based on test drives at different thrust levels. The tests in this study are performed as start-stop-tests, meaning that the TBM starts from zero to the maximum possible thrust and reverse with slowly increasing respectively decreasing steps (Frenzel et al., 2012). To gain information about the interaction between TBM and rock mass, a detailed geological documentation including an analysis of the discontinuity pattern and laboratory testing for rock strength characterization are mandatory.Within the last year 16 penetration tests have been performed. The results are thrust- penetration curves (Figure 2) showing that up to a certain penetration rate only crushing occurs (subcritical penetration). From there the desired rock fragmentation process called chipping takes place (Frenzel et al., 2012). These two different fragmentation processes can be described best by a bilinear function as seen in Figure 3. Both, CSM- and Gehring-model, do not fit to the trend of the penetration rates determined during the excavation process as they are using potential or simple linear functions.Another parameter that has to be implemented into the new prediction model is the influence of discontinuities. In case of favorable orientation and spacing, discontinuities reduce the required thrust at same penetration rates. In contrast, unfavorable discontinuity systems can cause blocky faces and hence worse performance than predicted. Besides discontinuities, the toughness of rocks has to be taken into account when predicting the penetration as tough rocks need more energy to obtain complete failure than brittle rocks.Key advantage of these tests in comparison to existing are more data points in less time. By improving respectively extending the existing penetration prediction models with the stated parameters, the penetration prediction for TBMs can be more accurate and also wear calculation can benefit from this approach."

Jan 1, 2015

By The Satff

"TEXADA Island is situated in the Strait of Georgia, about 100 miles northwest of Vancouver. The property of Texada Mines Ltd. lies on the southwest coast of the northern end of the Island. A part of the ""Sunshine Coast,"" the climate is moderate, with about 30 inches of rain during winter months and relatively dry summers. Texada has been shipping high-grade magnetite concentrate continuously since 1952 to Japanese ore buyers. In 1959, a 3,000-foot tunnel was driven just above sea level to explore the possible downward extension of known orebodies then being mined by open pit. In January of 1961, because the open-pit operations had a limited life, C. C. Huston and Associates were brought in as mining consultants to do a feasibility study on the possibility of going underground for production. This study was completed in March, 1961. With the completion of the report, the Company went to Japan seeking a ,long-term contract to justify the capital outlay necessary for setting up an underground operation. Concurrently, underground diamond drilling revealed more ore, and the Company planned some modifications to the concentrator for increasing the copper recovery. By November, 1961, a ten-year contract was signed with Japanese ore buyers for the sale of 450,-000 long tons of concentrates beginning in October, 1963. Since that time, the Company has built its own 65 000-ton ore carrier and an additional three-year contract has been negotiated, with an annual tonnage increase of from 450,000 to 550,000 tons."

Jan 1, 1967

By W. J. Stickney

"Over-all recovery of cadmium has been increased at the plants of the Hudson Bay Mining and Smelting Co., Limited, since the construction of a slag fuming plant and baghouse where smelter flue dust is recovered. This pa-per outlines the distribution of the cadmium in plant products from the concentrator to the refining department.The leaching of cadmium-bearing precipitates from the zinc plant is also discussed. This consists of a two-stage leach; first with sulphuric acid and then with copper sulphate. Details of the leaches are outlined along with the safety measures practised in handling the hydrogen and arsine evolved.The paper describes the final preparation of electrolyte for the refining cells by purification for copper and thallium. Deposition of cadmium, using a polyacrylamide as an addition agent, is discussed.An outline is given of the melting procedures, under either sodium hydroxide or zinc chloride, and of the sub-sequent treatment of the dross to recover entrained cadmium and thallium."

Jan 1, 1966

By R. O. Grieve

"IntroductionCALEY (1945) and Evans (1950) pointed out that certain instances of convergence between Devonian and Silurian horizons, frequently evident in wells drilled for oil and gas in Ontario, appear to be related to local thinning of salt beds in the Salina formation and they suggested that leaching of the salt beds may have occurred. Exploratory drilling by Imperial Oil Limited since 1945 has brought to light several examples of structures similar to those discussed by Caley and Evans. The writer has had the opportunity to examine cuttings and data from wells which penetrated these structures and the attempt to interpret them in the light of the theory of leaching and subsidence proposed by Landes ( 1945a) to explain the marked brecciation and deformation of Upper Silurian and Middle Devonian sediments which crop out in the Mackinac Straits region of northern Michigan has led to the observations presented in this paper."

Jan 1, 1955

By E. G. Gaylord

THE material improvements which have been made in the practice of exploiting oil and gas reservoirs in the United States during recent years may be attributed largely to: (1) The necessity for drilling deeper wells at costs not much greater than was formerly expended on shallower wells. (2) The necessity for producing oil at a lower cost per barrel. (3) A growing recognition of the importance of the nature of production practice upon ultimate yield of oil and gas. The first two of these factors result, to a large extent, from the fact that a greater proportion of new development has been deeper development, and these wells have been drilled in the face of progressively lower per well allowables. In California, for instance, maximum allowables have declined from 400 barrels per day in March, 1938, to 156 barrels per day in September, 1940, and during this same period some 125 wells were drilled to the deeper 10,000-foot producing horizons discovered during this time. The third item listed above results from our increasing knowledge of the basic factors which influence the amount of recovery we may expect from reservoirs. In addition to the longer-range planning now being undertaken by the more prudent operators, State proration and conservation laws have focused attention upon the importance of methods conducive to obtaining progressively greater quantities of the hydrocarbons in place. In a paper of this length it will be possible to discuss only a few of the recent advances. An effort has been made to select the more important of these and to indicate, where possible, the factors which have made these advances possible.

Jan 1, 1941

By H. Utsunomiya, J. Su, K. S. Tamimi, S. Yue, M. Sanjari, L. Kestens, A. S. Kabir, R. Petrov

The recrystallization and texture evolution of AZ31 sheets obtained through two stages was investigated at different stages of post-rolling annealing. The specimens were rolled at the temperature of 100? and at a fast speed of 1000m/min and low speed of 15m/min with a reduction of 30% in one pass. The results show thatAZ31B sheets rolled at 15 m/min and 100 °C has fractured for reductions of more than 30% per pass. However, by increasing the rolling speed to 1000 m/min the rollability was improved significantly and the material can be rolled to reductions of more than 70% per pass. The high speed and heavily deformed materials are fully recrystallized even at 100 °C.

Jan 1, 2015

By M. Sakata, H. Hata, K. Haiki

"Most of the secondary ZnO contains fluorine (F) in large quantities. Serious troubles at the zinc electrowinning are occurred by the cathode corrosion caused by F, therefore we developed iron compounds as F-adsorbents used in zinc sulfate solution. The iron compounds can be reused repeatedly as F-adsorbents because they can adsorb/desorb F alternatively depending on the pH. Moreover, if the adsorptive capacity decreases, we can dissolve and re-synthesize them easily. In this paper, results of the experimental process which consists of five steps (leaching, F removal, Cl removal, purification and electrowinning) to produce high purity electrolytic zinc from the secondary ZnO are reported. INTRODUCTIONThe recycle material for zinc, secondary ZnO, contains large amounts of fluorine (F) and chlorine (Cl) which are halogen elements, compared with calcine obtained by roasting of zinc sulfide concentrate. The halogen elements cause adverse effects in the zinc electrowinning process and particularly F causes corrosion of aluminum cathode plates and eventually sticking of electrodeposited zinc and therefore, F concentration in the electrolyte is controlled to less than approximately 20 mg/L. There are several methods to remove F from secondary ZnO, such as leaching with Na2CO3 or NaOH solution [1-2], vaporizing in a rotary kiln by roasting at 1000 to 1200 degrees C [3-4]. However, up to the moment, there has been no effective method for the removal of F from zinc electrolyte and it has been a big obstacle in treatment of secondary ZnO in electrowining of zinc.The authors, therefore, developed an iron compound used as an adsorbent of F in the zinc sulfate solution [5-8]. This iron compound is Akaganeite that has a crystalline structure of ß-FeOOH. Akaganeite is synthesized by neutralization of FeCl3 solution containing a small amount of SO4 2- with Na2CO3. When this iron compound is immersed into weak acidified zinc sulfate solution, F in the solution is adsorbed. F adsorbed in the iron compound is removed by immersing in weak alkaline solution and the iron compound can be reused as F adsorbent."

Jan 1, 2012

By E. De Souza

Energy associated with ventilating an underground operation comprises a significant portion of a mine operation's base energy demand and is consequently responsible for a large percentage of the total operating costs. Ventilation systems may account from 25?40% of the total energy costs and 40?50% of the energy consumption of a mine operation. Fans are the most important mechanical devices used to ventilate underground mines and the total fan power installed in a single mine operation can easily exceed 10,000 kW. Investigations of a number of mine main fan installations have determined their assemblage to be, in general, very energy inefficient. The author has found that 40?80% of the energy consumed by a main fan is used to overcome the resistance of fan assemblage components. This paper presents how engineering design principles can be applied to improve the performance and efficiency of fan installations, resulting in substantial reductions in power consumption, operating cost and greenhouse gas emissions. A detailed case study is presented to demonstrate that, by designing fan assemblages using proper engineering concepts of fluid physics and industrial ventilation design, main fan systems will operate at efficiencies well above 80?90% (compared to common operating efficiencies of between 20 and 65%), resulting in a drastic reduction in a mine's overall costs and base electrical and energy loads.

Aug 1, 2013

By Yuki Soma, Tsutomu Ogawa, Jae Hyung Hong, Toshihiro Nagato

The Saganoseki flash furnace was built in 1973. The steel frames of the flash furnace were designed to absorb the expansion of refractories and contain expansion-absorbing materials between their frames and the skin plate. Expansion and deformation resulted in the furnace settler because of the repeated increase and decrease in temperature from more than 30 maintenance shutdowns. Preliminary investigations were conducted to confirm the condition of the settler, and it was found that partial cracks accompanied the expansion in the lower layer of the refractories. As a result, the risk of molten-matte leakage increased. Based on the above investigation, it was decided that the entire settler should be replaced by introducing a spring-displacement structure that was capable of maintaining the furnace integrity over an extended period. The difficult redesign and rebuilding of the Saganoseki flash furnace was accomplished successfully and safely in 76 days from September to December 2017, as planned. Because of various redesigns, the furnace was changed to a flash-smelting furnace that can withstand higher thermal loads based on recent trends of copper concentrate with increased sulfur and reduced copper. The new furnace is operating smoothly at present. INTRODUCTION The flash-smelting furnace of Pan Pacific Copper Co., Ltd. Saganoseki Smelting & Refinary commenced operation in 1973, with an original designed feeding rate of 71 t/h. As a result of facility remodeling and operational improvements, shown in Figure 1, the feeding rate was increased to 215 t/h in recent years. After more than 40 years of operation, the original settler in the melt holding section of the flash furnace underwent significant expansion and deformation.

Jan 1, 2019

By G. Ergin

The interactions taking place between Al-Mg alloys and the bed media during aluminum filtration are not yet well understood. These interactions were studied using the infiltration technique. The reaction interface was analyzed using different techniques such as SEM and TEM. Only spinel formation was observed at the interface regardless of the type of alumina and contact time. This paper discusses the results of the study.

Jan 1, 2004

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

By W. L. Single

"LET ME FIRST OF ALL thank you for sending this invitation to me to participate in this Annual Meeting of The Mining Society of Nova Scotia. As an engineer, although I don't get an opportunity to practice very much engineering these days, I am, of course, always pleased to be able to meet with my fellow engineers to exchange views, but I must admit that today I feel a little bit out of place in the midst of all the experts that are here today. Let me make one thing clear - I'm a generalist! Your program states that I am to make a keynote address. I have always thought that a keynote speech is one that says something that has not been said before - announces some new program or policy, or says something startling. I am sure you will understand when I tell you that keynote addresses are made by politicians and that civil servants speaking publicly are usually expected to give an account of what is, or what is likely, to happen as a result of policies that have been announced in keynote speeches by politicians. I am reminded of a statement by a distinguished parliamentarian who said, ""However exalted a civil servant may be, he is not above the elected officials."" So today I will confine myself to giving you an overview with particular emphasis on the development side of oil and gas. The theme of ""Oil and Gas"" is a topical one these days. I suppose it's because of all the copy that is being generated by the media on the U.S. energy crisis, the Mid-East situation, the fact that most of the world's proven oil reserves are in Arab hands and, of course, the accelerated exploration activity that is taking place in the North Sea, in the Arctic, and off the coast of Newfoundland and Nova Scotia."

Jan 1, 1973

By H. R. Hammond, E. Sadar

Cominco is making substantial savings in secondary breaking by replacing dynamite with a new nitrate-based explosive. Compareo with dynamite. the new explosive, known locally as "Fine NCN," is significantly cheaper, more effective and safer to use. It also works better than prilled NCN, which is unsatisfactory for secondary blasting because of inadequate sensitivity, low strength and awkward handling properties. A simple apparatus has been devised for pulverizing prilled NCN to a fineness practical for effective secondary breaking. Blasting systems using cheap detonating cord for initiation have been developed.

Jan 1, 1966

By D. W. Rogers

Several commercial polyacrylamide flocculants most widely used in Western Canadian mineral processing plants have been analyzed chemically and compared in standardized settling tests as aids to thickening and clarification. Data are included for both dry and liquid-type flocculants. Percentages of active ingredients in these commercial products varied Widely. Performances were compared on the basis of: equal additions of active ingredients, nearly equal molecular weights and nearly equal degrees of ionic character. Based on zone settling velocities and supernatant clarities of siliceous slurries coagulated by lime additions, dry flocculants proved more economical than liquid flocculants. Using these same two criteria, the most highly anionic were more effective than either weakly anionic or non ionic polyacrylamide- type flocculants.

Jan 1, 1978

By K. Maruyama, T. Nagasaka, R. d. Chairaksa-Fujimoto, T. Miki

Electric arc furnace dust or EAF dust is considered as a hazardous waste but contains a significant amount of economically attractive non-ferrous metals especially zinc as zinc ferrite (ZnFe2O4) and zincite (ZnO). The hydrometallurgical process is one alternative choice because it has the advantage of low energy consumption. The leaching of ZnO from the dust is very easy. However, the complex major zinc compound in EAF dust is ZnFe2O4, which is very stable and insoluble in alkaline or acidic media under delicate conditions, and causes the low zinc recovery yield by hydrometallurgical process. Moreover, halogens and heavy metals in the dust are also problematic. In order to develop a new effective EAF dust treatment process, the authors have proposed "CaO addition process" as pre-dust treatment to transform all of ZnFe2O4 in the EAF dust to ZnO and Ca2Fe2O5. In this study, the selective zinc leaching from the CaO treated EAF dust with NaOH and NH4Cl solutions was carried out. The effect of temperature, reaction time and solute concentration were systematically investigated. All of zinc in CaO treated EAF dust was successfully leached into both solutions.

Jan 1, 2014

By Dong-Hyeun Koh, Yun-Soo Lee, Min-Seok Kim, Hyoung-Wook Kim

High strength AA7068 (Al - 7.88 wt.% Zn - 2.68 wt.% Mg - 2.07 wt.% Cu) aluminum alloy strip was successfully fabricated by horizontal-type twin roll casting. A simulation technique was used to obtain the range of casting conditions for fabricating strip without defects. The cast strip with thickness of about 5 mm was hot rolled, intermediate annealed, cold rolled to final thickness and subsequently annealed at various temperatures. Tensile properties of annealed and the aged specimens were evaluated at ambient temperature. Tensile strength and elongation of the annealed sheet are about 365 MPa and 28%, respectively. Also, the tensile and yield strength after the aging at paint baking condition (180 °C x 0.5 h) are 586 MPa and 551 MPa, respectively. Therefore, it is expected to show good formability prior to press or stamping and also provide high dent resistance after paint baking treatment.

Jan 1, 2015

By C. Gordon Saunders

"The ungraded-fibre mill is located at the mine site and has a rated capacity of 6,600 tons of ore input and 1,200 tons of ung1•aded fib1 •e product per day. Power for operation is obtained from a diesel generating plant located on the site, which has a capacity of 5,300 kW. The preliminary milling process consists of prima1•y and secondary crushing, drying and temporary storage of plus-1 1h -in. material. The final milling processes are two stages of crushing and three stages of screening, with air-lift separation of the fibre from the host rock. The central mill building also houses a machine shop, mill maintenance shops, a mobile equipment overhaul shop, an engine and majo1•-component overhaul shop, and a warehouse. Major changes to the milling ci1•cuits since start-up have been the addition of a larger secondary cone crusher, ct third dryer, adding a rotary distributor to the feed of the screening section and adding an automatic start-up sequence for all equipment except crushers and fans. The operation of the mill is coordinated from a central control room, where a ""mimic"" panel indicates the operation of all major units in both the ore preparation and the screening sections. Product quality is controlled by continuous sampling and frequent labo1•atory analysis, which provide data fm• the adjustment of aspirating hoods and mill feed rate. Operating problems unique to this location, and common to a sub-arctic environment, are discussed."

Jan 1, 1976

By H. A. Kishawy, S. Kannan, M. Balazinski

Metal Matrix Composites (MMCs) are new generation engineering materials that possess superior physical and mechanical properties compared to nonreinforced alloys. However, the presence of abrasive ceramic reinforcements in the ductile matrix causes severe tool wear and premature tool failure. Flank wear was found to be the dominant wear mode while the main wear mechanism was abrasion. Analysis of the cutting tools using scanning electron microscopy has shown that both two body and three body abrasion are operational during machining MMCs. A methodology for predicting the tool flank wear progression during bar turning ofMMCs was presented in an earlier paper [1]. In the proposed model, the wear volume due to two body and three body abrasion mechanisms was formulated. Then, the flank wear rate was quantified by considering the tool geometry in 3D turning. The main objective of this paper is to investigate the contribution of two body and three body abrasion towards the tool wear volume during cutting MMCs.

Jan 1, 2006

By Haofeng Xie, Lijun Peng, Xujun Mi, Xue Feng, Xiangqian Yin, Zhen Yang, Guojie Huang

The Cu/Al composite wires have been widely used in cable industry. Especially in the development of aerospace, the light weight character of wires is particularly important. The wires are fabricated by a drawing process and heat treatment. Mechanical and electrical properties are measured and analyzed. The bending behavior is studied by scanning electron microscope. INTRODUCTION Cu/Al composite is a typical bimetallic composite that has been used in plenty of fields such as automobile and aerospace. The composite has the advantages of excellent conductivity as well as low weight, which cannot be obtained from single copper or aluminum. Industrial products of Cu/Al composite include Cu/Al composite joints (Uscinowicz, R., 2013), Cu/Al bimetallic sheets (Li, X. et al., 2011), Cu/Al flat bar (Wu, Y. & Liu, X. & Xie, J., 2014) and CCA wires (Ahmed N., 1978). CCA wires refer to the composite wires that copper layer concentrically coated on the surface of aluminum core conductor, implementing solid combination of two metals on the interface and forming an integral. At present, the aircraft cable generally use copper or copper alloy conductor, which makes the wire in the aircraft occupy a considerable proportion due to the large density of copper. Therefore, the use of Cu/Al composite wires instead of copper wires for weight loss, is of great significance to the development of aerospace technology industry. Heat treatment is an indispensable procedure to improve plasticity during cold working process, which is of great importance to preparation of wires (Wang, Q. et al., 2008). During the heat treatment, the Intermetallic Compounds (IMCs) are inevitable formed at the contact area of Cu/Al due to the occurrence of diffusion (Lee, S. et al., 2012). According to the results of former researchers, kinds of IMCs were discovered. Antoine Gueydan (2014) identified the formation of three IMCs (Al2Cu, AlCu, and Al4Cu9) at the interface between copper and aluminum after thermal aging. IMCs have a significant effect to the properties of Cu/Al wires. Bending performance is a vital property for the actual application of wires. The brittle IMCs may create a stress concentration that can cause crack initiation during bending process. This work focus on the mechanical properties of Cu/Al composite wires after heat treatment. The effect of various annealing condition on mechanical and electrical properties are studied, in order to find the appropriate annealing conditions, which produce optimal combination properties of Cu/Al clad composite wires. Bending fracture of composite wires is discussed by morphology observation.

Jan 1, 2019