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By H. H. Claudet

PROBABLY the first flotation mill for treating molybdenite ores was put into operation .in Norway during 1913, when the writer was employed to introduce and apply the Elmore vacuum flotation process at a mine in southern Norway. These operations proved successful and led to other similar installations in that country. It remained, however, for Norwegian engineers themselves to iron out their difficulties and establish the molybdenum industry on a basis which ultimately attained world importance. Just as today, an urgent demand for molybdenum arose during the world war of 1914-18. By 1916, many molybdenite properties were in operation in Canada and several small concentrating mills were under construction. At one of these, in the Ottawa Valley district, the opportunity came for applying the Elmore vacuum flotation process, using a flow-sheet similar to that adopted in Norway. Later, as one of the staff of the General Engineering Company, who had already developed a highly efficient flowsheet for treating molybdenite ores, using the Callow pneumatic flotation process, the writer devoted considerable time to research work and investigations on a number of molybdenite projects and deposits in eastern Canada. The bulk of Canada's production of molybdenite was coming at that time from the Moss mine at Quyon, Que., where concentration of the ore was effected by water-film flotation. It is of interest to note that this process, based on the principle of surface tension, had been developed and introduced by the late Henry E. Wood, of Denver, Colorado- one of the original owners of the Moss mine-at the time he was investigating the Elmore vacuum process in his Denver plant. The process, with certain modifications, was used at several other properties in eastern Canada, and notably in the ore dressing laboratories of the Department of Mines at Ottawa and in a plant at Renfrew, Ont., in both of which ore from deposits in various parts of Canada was treated, with recovery of very appreciable amounts o much needed molybdenite. During the summer of 1917, the water-film flotation mill at the Moss mine was dismantled and the plant was re-modelled by the General Engineering Company to include the Callow system. This installation, using improved flotation methods, was highly successful both as to recovery and grade of concentrate, and proved a decided advance in molybdenite concentration, a recovery of upwards of 90 per cent being obtained, with a concentrate grading over 90 percent MoS2.

Jan 1, 1944

By Sunil S. Gandhi

"The Mountain Lake deposit is a tabular sandstone-type uranium deposit, hosted by the basal unit of Middle Proterozoic Dismal Lakes Group. Uranium occurs mainly as sooty pitchblende disseminated in stratiform lenses within gently dipping quartzose sandstone. It is associated with copper sulphides, pyrite, hematite, and traces of nickel and cobalt arsenides and of silver.Exploration HistoryUranium showings on the PEC claim group were discovered during 1969 by an airborne radiometric survey carried out over the Dismal Lakes-Great Bear Lake area by Aquitaine of Canada Limited (Bizard and Salat, 1969). Some drilling was done in the vicinity of the showings in 1975 by the company under a joint venture with Eldorado Nuclear Limited but the results were not encouraging (Hassard and Woollett, 1975). During 1972, Trigg, Woollett and Associates Limited conducting surveys for Imperial Oil Limited, discovered numerous high-grade radioactive boulders scattered over a distance of several kilometres north and west of the showings, and the area north of the PEC claims was staked as the YUK claims (Ahuja, 1974). A systematic study of the boulder distribution and Pleistocene geology suggested a source additional to the showings. More intensive exploration followed, and in 1976 drilling just north of the PEC claim group boundary intersected the main deposit at a depth of 75 m to 150 m, beneath overburden up to 60 m thick. Part of the deposit extends into the PEC claim group which is under exploration by the Aquitaine-Cominco Joint Venture.The following brief description is based on the presentations in 1978 by F. Hassard of Trigg, Woollett and Associates Limited at the Geoscience Forum in Yellowknife, and by S.S. Gandhi of the Geological Survey of Canada at the Mineralogical Association of Canada Uranium Short Course in Toronto."

Jan 1, 1986

By R. D. Brown

For the first time in years, the spring budgets of federal and provincial governments have not brought down major new proposals affecting the tax burdens of the mining industry in Canada. It seems appropriate to use this unaccustomed period of tranquility to set out an extremely abbreviated summary of the principal features of the federal and provincial income and mining tax rules affecting the mining industry.

Jan 1, 1977

By M. Reda

Because of the adverse environmental effect of Chromate, Molybdate ions had been investigated as replacement for Chromate and the results had shown not to be encouraging. Film deposited from peroxopolymolybdate (from reaction of Molybdenum meta, with excess Hydrogen Peroxide), are more robust than that deposited from molybdate solutions. This was shown to be due to higher fraction of Mo (IV) and Mo (V) that form from Mo (VI) in the peroxopolymolybdate deposited film than the film deposited from Molybdate solutions. The peroxopolymolybdate film contains 40% un-hydrated molybdic acid, tetraperoxodimolybdate and tetra peroxo tetra molybdate. The protective properties of peroxopolymolybdate were shown to be due to the effectiveness of the un-hydrated molybdic acid.

Jan 1, 2010

By Minghui Li

China is the largest coal producer in the world. In 2012, the coal production in China is 3.65billion tonnes, accounting for approximately 49% of global coal production. The raw coal production in 2012 was 3.8% more than the year 2011. 56% of total raw coal has been washed. The increase in raw coal production also promotes technology to be developed and brings separation capacity become larger and larger in coal processing in China. At present, over 40 extra-large scale coal preparation plants (each plant has capacity of more than 10 Mtpa) are in operation in China, the largest one is 32.5 Mtpa. Heavy medium separation are widely used in new built coal preparation, the washing limit for thermal coal feed lower and lower, the equipment selection tends larger which brings the whole washing system simplified, the local equipment developed and manufactured are more and more used. By discussing designs of several typical thermal coal preparation plants and coking coal preparation plants in China, this thesis introduces the current design of China?s extra-large coal preparation plants, and sums up the prevailing design features and trends of extra-large coal preparation plants.

Aug 1, 2013

By Yuki Koshino, Kenji Kaneko, Yasuhiro Aruga, Takuya Maeda

"In general, there is a strong correlation between dislocation characteristics and mechanical properties of aluminum alloys. In this study, dislocation characteristics of tensile deformed Al-Mg alloys were examined by transmission electron microscopy. An Increase in the solute concentration, ranging between 0.3 and 1.1%, Mg leads to increase in strength and decrease in uniform elongation. The accumulation of dislocations during the tensile deformation is observed in lower strain as the concentration of solute Mg in the alloy is higher. It is believed that the solute Mg in Al-Mg alloy promotes the accumulation of dislocation during the tensile deformation resulting in the decrease in elongation.INTRODUCTION The influences of the amount of Mg concentration on the tensile properties of Al-Mg alloys has been investigated by many researchers. It has been understood that the tensile ductility of Al-Mg alloy is higher for the Al-Mg alloys with higher Mg concentration beyond 2 mass% (Mukai, Higashi, Hirano & Tanimura, 1993). Uchida and Yoshida (1995) reported the formation of microbands during the tensile deformation due to the localization of dislocations, and the amount of microbands were reduced when the Mg concentration of the Al-Mg alloy was increased from 3 to 9 mass%. Their study suggested that the dynamic recovery of dislocation was retarded due to the increase of the Mg concentration during the tensile deformation, which resulted the increase in ductility. On the other hand, in the case of Al-Mg alloys with the Mg concentration less than 3 mass%, the reason why the ductility of Al-Mg alloys decreases with increasing Mg concentration has not been sufficiently investigated. In general, the Mg concentration used for automotive usage is less than 1 mass%, in the case of Al-Mg-Si alloys (Aoki, 2013). Therefore, to clarify the roles of Mg in the low concentration range on ductility of aluminum alloys and to elucidate its mechanism contribute to alloy design of Al-Mg-Si alloys having good formability."

Jan 1, 2018

By M. Maccagni, J. Nielsen

"The recovery of lead from battery paste has been investigated for a long time and with the use of many different electrolytes. A number of processes have been presented, but none of them reached even the demonstration step. Engitec has developed a new concept for the battery paste electrowinning using a chloride electrolyte fed through a very innovative flow cell. The process has passed the lab and the demo scale and it is ready to be introduced on the market. In this paper, a description of the process will be provided.INTRODUCTIONThe need for improved energy storage systems as well as the introduction of commercially viable electric vehicles is providing a strong compulsion toward the research of new batteries. The lead battery is playing an important role because it is inexpensive, reliable and it is the most recycled material. This last aspect marks the lead acid battery as quite peculiar making it both the primary lead based product and the main raw material for lead production.In the last years the legislative pressure has become very strong and has forced the lead production to react through the introduction of important process innovations and market changes. The dispersive products, such as additives for paints and for fuel as well as bullets, have been practically banned all over the world while the battery market continues to grow. The lead acid battery remains the cheapest and most integrated energy storage system available and is improving to meet the new technical challenges. This is testified by the news coming from the development of new and more efficient lead acid batteries which are confirming their leading position.Unfortunately, the image of lead is very negative in the public opinion and some important actions are required to try changing this sentiment. Among them, better information to the market and users and the introduction of new and cleaner technologies in the production of lead can help."

Jan 1, 2016

By Young C. Kim

A proper economic analysis of pit slope design must reflect the trade-off between the benefits and the increased risk of slope failure inherent in steeper slope angles. However, no formal framework for a proper analysis has existed to date. This paper summarizes the material contained in the Design Chapter Supplement (5-3) of the Pit Slope Manual. The supplement describes the results of the research effort in which a formal economic analysis framework was developed and tested through a case study. The case study results have demonstrated the practicality of the developed procedure and the availability of required data under "real-life" conditions.

Jan 1, 1979

By J. J. Barakso, S. J. Horsky, H. V. Warren

"A review of past and present biogeochemical studies is given. Early and more recent analytical procedures are described and compared. Tables 1-5 give silver concentrations in various organs of some plant species at different localities. Table 6 and conclusions provide guidelines for exploring for silver using biogeochemistry.IntroductionBiogeochemistry has been shown to be a useful tool in the search for gold deposits, especially those of the disseminated type (Warren and Barakso 1982). The purpose of this paper is to demonstrate that biogeochemistry can also be of assistance in searching for silver concentrations buried by as much as twenty feet of overburden without inflicting any damage on the environment."

Jan 1, 1984

By Marke Wong

? Vietnam?s economy is growing so fast that gross domestic product (GDP) growth remained above 8% in 2005 and exports are rising steadily at 25% per year. ? Demand for electricity is expected to increase 18% per year through 2010 requiring an additional estimated 7,547 MW before 2010 ? Domestic coal demand is expected to be over 45 Mt by 2010. ? The Quang Ninhcoal deposits are estimated at 6.5-7 billion tons (350m) Vietnam News Agency. Saturday, May, 6, 2006. ? National resources are now estimated at 10 billion tonnes; not including a relative new coal bed discovery estimated at 210 billion tonnesin the Red River Basin.

May 1, 2006

By Bernard Tougas, Franco Chiesa, David Levasseur, Bernard Duchesne

"In the present paper, the optimization of a tilt poured permanent mold will be carried out using filling and solidification modeling. This exercise resulted in 3 modifications of the initial mold design which was based on the foundry experience. The optimization provided a 20% improvement in the yield while increasing the output from 10 to 15 castings per hour.In a subsequent study, the value of the critical fraction solid of AlSi7Mg (A356) alloy was verified by radiographic analysis of the castings produced in the first 5 cycles of a run, which are necessary to bring the mold to a dynamic thermal equilibrium."

Jan 1, 2014

Agenda 1.Energy consumption and energy costs ?focus and failings 2.Energy efficiency methodologies, people and supporting tools 3.Energy cost saving case studies from three minerals processing plants 4.The operations team and the supporting role of Operations IT 5.Conclusion: Reducing energy consumption and energy costs There are many good Energy Efficiency Methodologies ?Energy and GHG Emissions, Management Guidance Document, The Mining Association of Canada ?Energy Savings Toolbox ?An Energy Audit Manual and Tool, Canadian Industry Program for Energy Conservation (CIPEC) ?Lean and Energy Toolkit, Achieving Process Excellence Using Less Energy, www.epa.gov/lean ?Energy Efficiency Opportunities Assessment Handbook, www.energyefficiencyopportunities.gov.au

May 1, 2010

By Ronald C. Schimmel

In 2006, the Corus IJmuiden pellet plant produced approximately 4.6 mln tonnes of pellets. Corus IJmuiden is about to increase its pig iron production to 6.4 mln tonne HM per annum. The burden of the Corus IJmuiden blast furnaces consists of approximately 50% high basicity sinter and 50% acid pellets, both produced in-house. To enable an increased iron production, the capacity of the pellet plant needs to be raised to 5.0 mln tonne per annum. The capacity is increased by modifications to the plant layout, which were implemented during the 2006 cold maintenance stop. In addition, the composition of the ore blends is optimised to gain productivity.

May 1, 2007

By A. F. Matheson

"Bankfield Consolidated Mines, Limited, and Tombill Gold Mines, Limited, in the Little Long Lac area, Ontario, mined an orebody that was common to both. The discovery' of this orebody was made by surface prospecting in May, 1932, on Bankfield ground, following an original discovery made in the same manner on the same property on a small reef in Magnet lake in October, 1931. The production from the two mines between 1937 and 1942 was approximately 135,000 oz. gold from about 420,000 tons of ore, an average grade of 0.32 oz. a ton. Production was nearly equally divided between the two properties. Both mines are now closed, the ore exhausted.""The ore is mainly sheared and fractured greywacke and porphyry impregnated by silica and small amounts of metallic minerals. To a lesser extent there are definite quartz veins in the ore zone""(l). The metallic minerals present were principally pyrite, arsenopyrite, pyrrhotite, and native gold .As at other mines in the Little Long Lac area, an elongated, broad, deep trough of folded, steeply dipping volcanic and sedimentary rocks, striking roughly east-west and surrounded by younger granite, is host to the orebodies of the Bankfield and Tombill. In the immediate area of the two mines iron formation and conglomerate bands occur nearby both north and south of an intrusion of porphyry-Cliorite, suggesting repetition of beds and folding. Although considerable drag folding is in evidence, folding on the above scale has neither been proved nor disproved."

Jan 1, 1954

By H. Hejny

Economy needs mineral raw materials in almost each sector of modern life. They can only be provided by mining activities. An increasing share of the total mining production will be by underground mining. The mineral deposits will be found at gradually greater depths, including all problems associated with them. It involves an increase in overburden pressure with subsequent rock stability problems and risks of structural collapse. There is a need for new and safe technologies for almost all parts of a modern mine. The mining industry faces a number of challenges which require technical solutions that encompass the entire network and include the economic, social and environmental issues. The industry needs a new image based on pioneering solutions and a modern structure that can exploit minerals at greater depths and promote both high productivity and safe working conditions. Funding has been secured from the European Commission for the I²Mine project. Work started in November, 2011. This initiative is designed to focus on the technological challenges that the mining industry is currently facing including the exploitation of ever deeper deposits and the aspiration for an invisible, safe, zero impact mine. The project comprises a consortium of 27 organisations from 10 European countries. I²Mine marks the start of a series of development activities aimed at realising the concept of an invisible, zero impact, deep mine. The extractive sector, still seen as being old fashioned and environmentally unfriendly, will show that mineral extraction and processing can be done in a highly innovative and sustainable manner with low impact underground and zero impact above ground. The concept of I²Mine is to develop innovative methods, technologies, machines and equipment necessary for the efficient exploitation of minerals and disposal of waste, all of which will be carried out underground. This will dramatically reduce the volume of surface transportation of both minerals and waste, minimising above ground installations and reducing the environmental impact. New eco-efficient technologies will be applied in order to make the entire mining process more efficient and environmentally sound. The concept is for an integrated mine, with the majority of the installations underground, and only the final product will be transported above ground to be shipped to the customer. Production waste will be treated and stored underground and gaseous emissions will be managed underground as far as practical. I²Mine will also focus on ideas and concepts that increase energy efficiency and decrease waste. The core of the project will be to develop breakthrough technologies for autonomous, highly selective, continuous mineral extraction processes and machinery based on new sensor technologies, face front separation as well as innovative concepts for mass flow management and transportation integrating state of the art technologies. The concept of an invisible, zero impact mine requires a refined process underground that selectively extracts the mineral thereby reducing waste. For this reason, improved extraction machines and near to face processing methods, including backfill procedures, need to be developed. These developments include rock mechanics and ground control solutions, incorporating health, safety and environmental issues.

Aug 1, 2013

By G. Goodlad

This paper describes some of the main aspects involved in implementing the European “Equipment and Protective Systems for Use in Potentially Explosive Atmospheres” (ATEX) Directive (No.94/9/EC) in the British mining industry by the year 2003. It provides a brief background to the Directive and considers its main objective of removing all barriers to trade in Europe. It outlines the need for the European Standards making bodies to write new editions of the ’explosion protection concept standards’ and for manufacturers to adopt new quality management procedures and develop new versions of equipment in conformity with the ATEX categories of “M1” or “M2.” Finally, it assesses the possible future relationship between the European enforcing authorities, manufacturers and users of explosion protected equipment.

Jan 1, 1999

By Y. Béliveau

Emission of perfluorocarbon gases, CF4 and C2F6, produced during anode effects from aluminum electrolytic cells are a significant part of the total equivalent CO2 emitted by aluminum plants. With the current concerns about global warming, the reduction of these PFC gases is a key issue in reducing greenhouse gases for a smelter and achieving GHG emission agreement goals. This paper will present the approach taken by the Alcoa vertical-stud Soderberg plant in Baie-Comeau to reduce GHG emissions generated during anode effects and close emission gaps with other Alcoa Soderberg plants. The approach has been to adapt the existing technology in place at the Baie-Comeau Soderberg plant. PFC emissions were lowered by reducing both the anode effect duration and frequency through different methods. Examples of change include: implementing skimming practices and wider side crust break area for better alumina dissolution in bath, increasing the ratio between reacted and pure alumina, reducing the time to declare anode effects in the potrooms, implementing best work practices and finally educating the workforce on the importance of reducing PFC emissions.

Jan 1, 2007

By Jim Richard

Introduction Electric Vehicle Controllers (EVC) and the Northern Centre for Advanced Technology (NORCAT) have created two generations of Lunar Highland Simulant ?Simulant preparation techniques and equipment resulted from drilling activities in support of Regolith and Environment Science and Oxygen and Lunar Volatiles Extraction (RESOLVE ) ?The purpose of defining the compaction process was to minimize the effect of density on drill testing This allowed other variables including drill bit geometry, auger, RPM, and thrust to be evaluated independent of density ?Density of Highland Regolith falls within a range of 1.40 to 2.29 g/cm3 (p484 Lunar Source Book)

May 1, 2013

By R. R. Irrinki

Abstract -The Key Anacon deposit consists of four sulfide zones called, from south to north : Key Anacon No. 1, Key Anacon No. 2, Key Anacon No. 3, and Key Anacon Copper Zone. Massive sulfides of zones 1, 2, and 3 are underlain by rocks correlated with the Nepisiguit Falls Formation and are overlain by matie volcanic rocks correlative with the Boucher Brook Formation. In contrast to zones 1, 2, and 3, narrow northwesterly-trend.ing, copper-rich fracture zones occur within the Patrick Brook Formation. Sulfides in zone 2 occur as three mineralogical associations, namely: pyrite-chalcopyrite, pyrite-sphalerite-galerta, and pyrrhotite-sphalerite-galerta. The distribution of lithologies and en-echelon patterns of the three sulfide lenses of Key Anacon No. 2 zone are the result of F1 and F2 folding. Zone 2 is the most promising economically, with proven reserves of 1.11 million tonnes grading 0.2207o Cu, 3.47% Pb, 8.41% Zn, and 96 g/t Ag; the zone is open below a depth of 427 m.

Jan 1, 1992

By M. Hekmati1

SAG/AG mills have been most common choice in grinding circuits last decades. In the most cases, at the discharge of SAG/AG mills, a trommel screen is used that is equipped with baffles to provide appropriate residence time and improve separation efficiency. Using baffles, with the resultant maintenance requirements could lead to decrease in mill availability. In this research, an innovation in the structure of baffles of a trommel is presented. The results show that using new baffles led to 67% decrease in SAG mill downtime due to problems of baffles and 80% decrease in fine particles on recycle conveyor.

Jan 1, 2012