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By H. Abdollahi

Cold rolling is one of the most important techniques in metal forming since the cold rolling products are almost finished product, The product quality of this process is widely influenced by friction in the roll gap; therefore, controlling the friction and other parameters affecting the cold rolling is very important in order to have a product with high quality, Among the cold rolling parameters, the pressure distribution or friction hill within the roll gap is known as the most significant one, In this study, a new software (Matroll), is introduced which can determine the coefficient of friction (COF) and plot the friction hills for an industrial mill, Besides, based on rolling equations, it offers about 25 rolling parameters as outputs. To verify the software operation, the real industrial rolling data was used as inputs, The results (outputs) are in good agreements with the findings of other researchers, The COF values are very reasonable, The friction hill shows that COF is not constant over the whole arc of contact.

Jan 1, 2005

? The Mining Association of British Columbia (MABC) was established through an Act of Parliament in 1901 ? The MABC represents the interests of B.C.?s ? Coal and mineral mining companies ? Smelting companies ? Advanced stage development projects ? Key areas of work: ? Environment, Health and Safety ? Policy & Government Relations ? Knowledge and Information Services

May 1, 2008

By J. E. Hawley

"IntroductionA STUDY of the trace elements in the ash •of coals from nine seams in the Sydney coalfield, Nova Scotia, was undertaken at the suggestion of Dr. W. A. Bell, Geological Survey of Canada, as a part of a larger study of these and other Nova Scotia coals being made by the Geological Survey and the Nova Scotia Department of Mines under the direction of Dr. P. A. Hacquebard.The main purpose of this investigation has been to •determine if a knowledge of the trace element distribution might be of assistance in the recognition of individual seams, the distinction of which is not always easy or positive in folded and faulted strata by ordinary stratigraphic and structural means.The study has been so conducted as to afford information on the variation of trace elements in individual petrographic intervals or divisions in each of the seams examined, intervals determined by Dr. Hacquebard on the basis of their banded ingredients, vitrain, clarain, durain, fusain, etc, as observed under the microscope in polished sections. The results, as well, indicate the trace element composition of the coals of the area as a whole, and quantitative data for fifteen elements are given, along with concentrations of thirteen other elements, stated in terms of intensity ratios. Data on distribution of germanium, though considered here along with other elements, are dealt with elsewhere*."

Jan 1, 1955

By Frank Condon

?Location ?Background ?Drilling Program ?Mineral Resources ?Geology ?Economic Assessment ?Strategic Partner ?Located in Nunavik, Québec ?160 km northwest of Schefferville ?240 km south of Kuujjuaq ?160 km northeast of Brisay ?Magnetic Anomaly ?Property Boundary ?Diamond Drill Holes

May 1, 2011

By Gordon A. Irons, H. Y. Hwang

An impinging gas jet on a water surface was studied to understand momentum transfer in oxygen steelmaking. Depth, width and oscillation frequency of the jet cavity were measured and the splashes interpreted with Kelvin-Helmholtz instability and combined Rayleigh-Taylor and Kelvin-Helmholtz instability theory. A model to calculate separate gas and liquid velocities, applying the exact momentum boundary condition, is proposed.

Jan 1, 2004

By B. Kenney

For SOFCs, composite cathodes comprising an electronically conducting electro¬catalyst (e.g. LSM) and an conically conducting electrolyte material (e.g. YSZ) are considered to improve the electrochemical performance by extending the active reaction zone to regions beyond the electrolyte-electrode interface, as in the case of conventional cathodes. Interpretation of experimental data for composite cathodes, however, is complicated by the mixed conducting behaviour which results in local overpotential distributions throughout the composite cathode. These local overpotentials depend on many factors, such as the composition, particle size, porosity and thickness of the cathode. Reliable experimental data obtained from composite cathodes requires carefully crafted microstructural parameters in order to minimize the overpotential variations. A mathematical model of a composite cathode was developed using coupled differential equations describing transport and consumption of chemical species, oxygen ion and electrons. Simulations under various oxygen concentrations were used to obtain the reaction order of the oxygen reduction reaction. An apparent po2 dependency was then extracted from the predicted Rp vs P02 data. It was found that this p02 dependency can be significantly influenced by the micro-structural parameters of a composite cathode, primarily due to local overpotential distributions.

Jan 1, 2005

By S. Nafisi

Permanent mould casting may be regarded as a near net shape manufacturing process where simple to very complex shaped engineering components are fabricated with high degree of precision in a metallic mould, In this group, High Pressure Die Casting (HPDC), have attracted more attention because of its production rate, where both liquid and semisolid metals (SSM) can be cast with high degree of precision and versatility. The SEED process, Swirled Enthalpy Equilibration Device, the new process for semi solid metals slurry production route, consists of two steps: The initial step involves extracting specified amount of heat from the molten metal to generate liquid-solid slurry, i.e, mushy structure, followed by drainage of remaining liquid to produce a compact free standing feedstock for rheocasting operation. In this paper, microstructural evolution during the process and some initial casting results of automotive components an also reported.

Jan 1, 2005

By Stephan I. Zajac, Roger A. Blais, John B. Stubbins

THE iron deposits of central Labrador occur within a relatively small area, herein called the Knob Lake Iron Range, in which a northwest-trending series of low hills and ridges defines the height-of-land at the boundary between provinces of Quebec and Newfound-land. Approximately two-thirds of the deposits are in Quebec and the remainder in Labrador, with several deposits straddling the inter-provincial boundary. These deposits are being exploited in open-pit mines by the Iron Ore Company of Canada centered at Schefferville, Quebec. Since 1954 this company has produced more than 56 million tons of iron ore to become Canada's leading iron ore producer. With indicated reserves of more than 375 million tons of direct-shipping ore and large tonnages of iron formation amenable to beneficiation, this mining district is assured of a long life. This paper describes the Knob Lake iron ores and their geological settings and stresses the features that lead to a better understanding of their origin. The

Jan 1, 1961

By Kim H. Shikaze, John R. Hawley

"Even though acid mine drainage is an old problem, particularly in coal mining areas, its appearance in the form of a major environmental hazard in the hardrock mining districts of Ontario was unexpected. The yellow and amber coloured wastes that characterize an acid mine drainage situation were first noted by the Ontario Water Resources Commission in the uranium mining Elliot Lake district. Problems of a similar nature were also noted in the copper-lead-zinc camp at Manitouwadge, the nickel camp at Sudbury and at numerous isolated base metal properties, both in and out of the Province of Ontario.Without exception, when acid mine drainage type effluents were evident, the specific companies involved worked sulphide or sulphide-associated ores. Without exception, the ore bodies contained quantities of iron sulphide (in various mineralogical forms) and, without exception, the milling circuits serving these operations were such that the iron sulphides were rejected to the tailings areas as waste.Once in a tailings area and after a varying period of time, iron sulphides react to form water soluble salts which, when discharged in the effluents from the tailings area, can affect stream chemistry and stream ecology.It is not unusual that the minerals pyrite, marcasite and pyrrhotite (all iron sulphides) react to form a stable oxide under atmospheric conditions. The law of stability of rocks and minerals, for instance, states that rocks and minerals are stable only in the environment of their formation and, as the environment surrounding them changes, the rocks and minerals tend to change to other species which are relatively more nearly stable under the conditions of the new environment (a). Under atmospheric conditions, iron oxide exhibits a greater stability than iron sulphide."

Jan 1, 1971

By K. B. Young

Possibly the most complex fatigue problem associated with the development of the axial-flow 'gas turbine is discussed in its broader aspects from the metallurgical viewpoint. Reference is made to nodal patterns, interference diagrams, etc. The use of such data in analysis of a turbine :blade failure is illustrated. Special attention is given to the influence of some metallurgical variables affecting fatigue strength and, in particular, heat treatment is shown to have a pronounced effect on .the relative fatigue and creep strength properties of a nickel-chromium-cobalt base alloy suitable for turbine blade applications.

Jan 1, 1958

By Ron Ferris

The Westinghouse Temptifier TM, using heat pump principles, recovers lowgrade waste heat in the 600P to 1600P temperature range and amplifies it to usable levels of up to 2200P. Coefficients of performance (C.P.D.) normally encountered are from 3.0 to 6.0, with capacities from 200,000 to 10 million Btu/hr.

Jan 1, 1979

By J. Mrozowski, R. Kurowski, A. Chmielarz, Z. Szolomicki

PbSO4 is a commonly encountered component of the materials used in lead recycling (e.g. battery paste) and in by-products of metallurgical processes (e.g. residues from zinc hydrometallurgy, dust from copper smelting). Smelting of battery paste results in SO2 emission and in generation of significant amounts of hazardous ‘white slag’. Those adverse phenomena can be eliminated by removal of sulphur from the paste. Lead-bearing by-product materials are of polymetallic character with usually low Pb content, which makes lead recovery technologically difficult and uneconomic. However it can be successfully achieved by extraction of lead sulphate from solid phase with triethylenetetramine (TETA) water solutions. That compound has capability for selective solvation of a whole lead sulphate molecule. Virtually pure lead carbonate can be precipitated by means of saturation of lead-loaded aqueous TETA solution with carbon dioxide, and complete regeneration of the extractant is achieved by fixing of sulphate ion into gypsum through operation of calcium hydroxide suspension. The paper presents results of the lab and pilot scale studies into process of battery paste desulphurisation and recovery of lead from the residue of zinc calcine leaching.

Jan 1, 2014

By V. Itkin

"Three methods were tested for the beneficiation of aluminum scrap, generated by heavy medium separation of non-ferrous automobile scrap residue. These were: crushing in a shredder followed by screening; grinding in a ball miff followed by screening; and eddy current separation. The best results were obtained with the grinding-screening method. IntroductionThe usual method of aluminum alloy reclamation from non-ferrous automobile scrap residue consists of a two-step heavy medium separation to remove materials lighter than and heavier than aluminum. The resulting aluminum scrap still contains over 15% impurities such as stones and glass, heavy rubber, insulated copper wire , plastics and heavy metals entrapped by macerated aluminum piece s, composite fragments, etc.(2). Upon melting, these impurities create difficulties and yield a low ingot recovery-65% to 70%, hence small foundries avoid this material.There are a number of ways to improve the quality of aluminum scrap such as:(1 ) crushing of the scrap, which powders the brittle content , a major impurity component, followed by screening out of the dust(2) eddy current separation , which removes metals from the material flow, and(3) implement better methods for density separation.The eddy current separation and two variants of the comminution-screening technique were studied by Intermetco Ltd., Hamilton , Ontario."

Jan 1, 1986

By Stavros A. Argyropoulos, Radhakrishna Valiveti, Bernard Closset

"The use of microprocessors in metallurgy is currently increasing at a very fast rate. A large number of companies are offering systems ""off the shelf"" which are aimed at the data acquisition and process control market. There are two main drawbacks to these systems: first, they are usually quite expensive, and second, they are not completely compatible with the target metallurgical application. An alternative is to develop a microcomputer-based system "" in lab "".A dedicated microcomputer system has proved to be very useful in many metallurgical research applications(1,2)). However, in this system the analog input signals had to be transferred over long distances , and significant noise was introduced despite the use of shielded cables. In order to overcome this problem a network of low pass-filter s was designed and built. The usage of the abovementioned system brought the need to digitize the analog signals in-situ and transfer the digital signals, which are much less susceptible to noise over very long distances. This distinctly different design philosophy has become a reality with the evolution of microprocessor technology over the last few years. This design philosophy is utilized in this development."

Jan 1, 1984

By Dillon. Patricia

Business Growth ?Coal ?Targeting 30 million tonnes by 2013 compared to 19 million tonnes produced in 2009 ?Expanding Energy Business unit (Oil Sands) ?Copper -Strong growth potential for existing operations and development projects ?New gold strategy recently launched ?New markets for zinc Need to retain existing and attract new employees to support growth Engaged Employee ?Has a positive attitude towards the organization and its values ?Is a person who is fully involved in, and enthusiastic about, his or her work Engaged employees are more likely to stay with the organization.

May 1, 2010

The cost benefits of controlling dilution of extracted ore have been very well understood by miners and mining professionals for many years. However, as we strive towards more mechanization, the dilution factor has been compromised in order to fit ?equipment? that is better suited to provide improved safety and productivity. Alternately, the drilling and ground support is accomplished by handheld drilling. In 2007, a short study, commissioned by CAMIRO (Canadian Mining Industry Research Organization) on the safety of hand held drilling vs. mechanized drilling, concluded that the risk of injury with handheld drills was seven times greater than with mechanized drills. Armed with this data, MEDATech Engineering proposed to the CAMIRO group to fund development of a ?MICRO Bolter?.

May 1, 2009

By C. Rodgers, E. (Ted) Warren

"LocationThe Key Lake operation of Cameco Corporation is located at latitude 57°N in northern Saskatchewan, within the southem boundary of the Athabasca formation. The nearest city is LaRonge, located 240 km to the south. Access to the mine is by all-weather road and by private airstrip.Description of OperationThe mill was designed to produce twelve million pounds of uranium oxide (U3O8) a year from a feed grade of 2.4% U3O8. Current production is fourteen million pounds from 2.0% feed.Following grinding, the uranium is leached using sulphuric acid and oxygen in autoclaves. An eight thickener counter current decantation (CCD) circuit is used to separate the uranium-bearing solution from the solid waste residue. The uranium in solution is further purified in a solvent extraction circuit. The purified uranium is then precipitated using ammonia, calcined at 840°C, and packaged in drums for shipping to refineries. There is a crystallization circuit to recover excess ammonium sulphate produced in the process, and a waste treatment circuit.HistoryUranerz Exploration and Mining discovered the Gaertner and Deilmann orebodies in 1975 and 1976, respectively. Between 1975 and 1977, Uranerz conducted laboratory studies and delineated a process for the Key Lake ore known as the ""Bonn process."" In 1977, Sherritt Gordon Mines Ltd. was retained to conduct further studies in cooperation with U ranerz. The technical feasibility of the Bonn process was generally confirmed. Howeve1~ alternative processing methods also appeared feasible, and over the period 1978-1979, a detailed research and development program was conducted to finalize the processes to be used and to provide data for design of the plant."

Jan 1, 2000

By L. E. Djingheuzian

IN 1953, Lewis (1) published an article which brought forth a great amount of discussion by grinding engineers. In his contribution to discussion the present writer (2) suggested that, for the most efficient performance of a ball mill, there must be a .definite relationship between Cn, per cent critical speed, and V p, per cent mill volume occupied by the ball charge. Later, he ( 3) was able to publish some grinding data from Wright-Hargreaves milly which appeared to bear out this contention. It is with this view to establishing a fundamental relationship between Cn and Vp that the idea of this Forum was conceived. Accordingly, a questionnaire was prepared and copies of it were mailed to over eighty Canadian mill operators. This questionnaire did not include a question on dilution on the assumption that each mill operator was using the most efficient dilution for his operation, nor was a question on efficiency of classification included since it was thought that the inclusion of efficiency of dassification in the questionnaire at this preliminary stage might render the forum discussion,. while everybody was trying to find his bearings, too unwieldy. However, it is evident that, as discussions develop, this forum will have to define a uniform method for establishing most efficient classification in grinding circuits

Jan 1, 1957

Agenda ?Introduction ?Geology ?Mining ?Metallurgy ?Process, Layout ?Environmental Background ?Kinross Gold Corporation owns the Lobo-Marte gold property, located in Region III of northern Chile. ?The property is close to two other Kinross mines, Maricunga 50kmto the south and La Coipa 60km to the north, plus a regional office in Copiapo and district level operating synergies are expected. ?Lobo and Marte were discovered in the early 1980s and are intrusion-hosted, porphyry-type precious metal deposits, typical of the Maricunga District. ?The Marte open pit heap leach mine was in commercial production in late 1988, but was suspended in February 1992 as it did not meet forecasted production levels and recoveries. ?Kinross plans to recover ore from the Lobo and Marte deposits through an open-pit, heap leach47,000tonne per day operation.

May 1, 2010

By L. Mohammadi

Outline ?Background on the accident at the Sullivan Mine No.1 Waste Dump ?Holistic approach to understand the reason for accidents (Atmospheric) ?Specific hazards at reclamation sites ?Regular atmospheric risk assessment at reclamation sites ?Fuzzy risk assessment ?Managing risk at legacy sites

May 1, 2010