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By S. Orzecki

The KGHM Copper Refinery Plant, Glogów 1, has operated for 35 years and -increased its capacity almost ten times.Cathode quality, expressed in terms of the total impurity content, has undergone a five-fold improvement. The present refining capacity is equivalent to 240,000 metric tonnes of copper cathode, with a total impurity content of 20 ppm, inclusive of 10 ppm Ag. These accomplishments result from combined implementation of current technological progress in electrolytic refining and KGHM's own solutions applied to the Glogów Refinery. The quality improvement measures feature both lowering actual current density, despite an increase in nominal current density, and diminishing the role of non-ion mechanisms which transfer impurities to cathodes. The paper contains a detailed discussion of these issues and outlines possible measures aimed at further production and quality improvements.

Jan 1, 2007

By W. T. Thompson, S. Durham, K. M. Jaansalu

The role of platinum on the relative stability of gamma - gamma prime equilibrium is only qualitatively known, and may bear upon the stability of a superalloy under a protective coating. The binary phase diagrams Ni-Pt and Al-Pt, and the Ni-rich corner of the Ni-Al-Pt ternary, are reviewed and simple self-consistent thermodynamic models are derived. These thermodynamic models are incorporated into a database used to predict the gamma-gamma prime equilibrium for single crystal superalloys. In small concentrations, platinum is predicted to increase the temperature stability, but not the proportion, of the gamma prime phase over the gamma phase in third generation alloys such as CMSX-10. Another effect of platinum addition is to significantly lower the solidus temperature. These findings are compared to experimental data in the literature.

Jan 1, 2004

By W. M. Silva, Bittencourt. L. R. M.

Three newly developed alumino-silicate refractory bricks for use in safety lining of aluminum electrolysis cells were compared to one commonly used bricks for the same application. It was shown that the increase in silica content and decrease in permeability led to a sensitive decrease in cryolite attack. Both parameters are of utmost importance in selecting bricks for these cells. The reasons for this observation were the formation of a more viscous liquid after the reaction between molten cryolite and the brick, and the reduction of the rate of penetration. Moreover, a novel mortar with high silica content was tested and has shown improved resistance to molten cryolite. The use of oxidizing atmosphere led to increased attack rate in the brick when compared to reducing condition. The opposite effect was observed in the mortars.

Jan 1, 2004

What Discounted Cash Flow Analysis can do for you: ?Provide an accurate financial analysis of a project for the first 25 to 30 years of operations ?Identify cash flow requirements ?Identify relative sensitivity of the project to the various input parameters ?Place a value on the resource in place after 30 years of operations ?Correct for errors in input parameters

May 1, 2010

By Michael Sudbury

Introduction The essence of a good presentation is said to be: Outline what you are going to say Say it Summarize what you said This is perhaps especially good advice at 8.30 a.m. So here goes: This is an attempt to put numbers on three inextricably linked subjects: People and the Future Irrigation and Agriculture Mine Water and Mine Waste

May 1, 2013

By Cheng-Ting Chiang

Information integration and exchange for the entire building life cycle is one of the most important issues in the AEC industry. Although the Building Information Model (BIM) technology is widely utilized to address them, BIM is mainly concerned within the design and construction (D&C) phases. In the operation and maintenance (O&M) phases, however, the information integration and exchange issue becomes more complicated because software applications here require not only BIM but other information outside of the AEC domain, e.g., disaster mitigation. Nowadays, most BIM-related research focuses on the D&C phases and pays less concern on the O&M phases, hence there is a research need that can help seamlessly transfer the information between the D&C and O&M phases. In this research, a software framework using ontology was designed to deal with aforementioned problems. The BIM data from the D&C phases were used as a foundation to generate new models for different software applications for the O&M phases. The ontology technique was employed to assist the model transformation process between the original BIM and the models for applications. Finally, a disaster mitigation example was chosen to validate the framework, in order to make sure that the transformation process is comprehensive and useful from domain experts? perspective.

Aug 1, 2013

By M. A. Vos

"Aggregates are the low-cost mineral raw material of building construction. Large volumes of aggregate are consumed each year. The availability of aggregates in southern Ontario is discussed in the context of the geological formations in which they occur. Sand and gravel are abundant in glacial deposits and in recent sediments. A knowledge of the glacial history is important for their discovery. Bedrock formations provide a variety of aggregates in Ontario. Knowledge of the rock types involved and of the depth of overburden are important for evaluation of the aggregate potential of bedrock resources in an area. Utilization of available resources intensifies as the population increases. Urban development makes it progressively more difficult to satisfy the demands of the construction industry. The effects of urban development on the aggregate resource base of an area are illustrated by developments and consumption statistics in the Toronto- centred region. There is an obvious need for a comprehensive survey of available resources in urban areas to serve as a guide in land-use planning. To fill this need, staff members of the Industrial Minerals Section, Geological Branch, Ontario Department of Mines and Northern Affairs, are engaged in mapping projects and mineral resource studies in southern Ontario as well as in some urban areas of northern Ontario."

Jan 1, 1972

By W. Zieman

"The low consumption of reagents can probably be attributed to a good clean type of ore. The cyanide level is kept at 0. 8 lb/ ton of solution and the lime at 1. 8 to 1.9 lb per ton of solution (pH 12. 2 to 12 .3). Experience in cutting down the lime level in half produced troubles in the presses, in the refinery and resulted in higher cyanide consumption. Finally the residue increased under these conditions, High lime always seems to prevent the trouble from occurring.A survey at one mine of the taxable work, performed in the mine shops for use in the mine, showed that under the new regulations, this had increased some 30 times what it was before the new rules came into effect on June 14, 1963.A water softener idea is incorporated at Lamaque with the crude addition of 100 lb of lime per shift to a spare agitator to precipitate the bicarbonates as carbonates from the water before it enters the mill. The lime titration of the softened water is about 0,2 to 0.3 lb per ton of solution (pH 11). This water is used mainly on the filters as washes."

Jan 1, 1964

By P. W. Ware

The majority of all refined copper is consumed to produce electrical conductors. Most copper conductors are drawn into wire from 8 mm ETP copper rod produced from high purity copper cathodes. Southwire Company has more than 40 years experience using, designing, fabricating and marketing a process for continuously producing ETP copper wire rod. This process is called the SCR® (Southwire Continuous Rod) process. Today, approximately half the copper wire rod produced in the world, or more than one third of all refined copper consumed, is produced using the SCR process. Southwire has sold 75 SCR copper rod mills to metal producers and wire manufacturers around the world. Southwire is North America's largest electrical wire and cable producer. Southwire operates a 48 metric ton per hour SCR® copper rod system in Carrollton, Georgia. This allows Southwire to provide technical support for existing SCR® system customers based on first-hand knowledge. Rod fabricators and their wire customers are always striving for copper rod that improves productivity. They are looking for improved surface quality, finer wire sizes and fewer wire breaks per ton of rod drawn. This paper will present a brief history of the SCR® process, a description and recent process developments.

Jan 1, 2007

By S. Itoh, T. Nagasaka, J. Ono

With respect to the recycling of used lead-batteries, a pure lead is required to prepare a lead-calcium alloy electrode for a new maintenance-free battery. The pure lead can be obtained by means of electrolytic and/or pyrometallurgical refining. In the lead electrorefming, antimony is concentrated in anode slime. From the viewpoint of the recycling and recovery of metal values from used lead-batteries, especially from anode slime, oxidation experiments were conducted for pure liquid antimony in the temperature range between 973 and 1373 K to elucidate the oxidation kinetics and mechanism. Furthermore, since lead anode slime generally consists of antimony, lead and bismuth, experiments have been also carried out using antimony-lead-bismuth alloy. The equation relating to the mass transfer characteristics in the gas phase was then applied to analyze the oxidation kinetics. As a result, it was found that the anode slime treatment, that is, an oxidation of antimony concentrated in anode slime followed by vaporization as antimony oxide Sb406, should be operated with higher oxygen partial pressure and sufficient amount of gas flow rate at lower temperature around 1073 K. The feasibility of the oxidation treatment for anode slime has been also discussed.

Jan 1, 2004

By T. Stergiou

An extensive research is being carried out on the shaft furnace operation in order to minimize down-times and reduce operational cost. The need to increase the scrap percentage on the charging mix, together with the need of cheaper spare parts has led to the investigation of alternative materials for the burner system on the shaft furnace. This system consists of a burner block and a flame holder. Traditionally these items are constructed either from SiC ? oxide bonded or SiC-nitride bonded. A lot of problems have been confronted over the past 8 years of operation. Usually, large cracks are formed on both flame holders and burner blocks. This resulted in leakage of combustion gases to the back of the lining and a quick erosion of it. Additionally, the burner blocks suffer from chemical erosion, due to the increased amount of scrap used in the charging mix and the presence of slag inside the furnace. Alternative materials such as stainless steel for the flame holder and alumina-chromia refractory for the burner block have been tested in terms of life-time and resistance on chemical erosion. Furthermore, additional changes have been made on the burner block design in order to alter the flame shape and improve the scrap melting operation.

Jan 1, 2007

By M. Sabau

The Electrowinning Plant at INCO's Copper Cliff Nickel Refinery is a precious metals upgrading plant. The feed to the plant contains copper, nickel, cobalt, iron, significant amounts of precious metals and some impurities. Copper is the most abundant element in the feed. This paper describes the major equipment and process changes over the last twenty years, geared to improve the tankhouse operation, workroom environment and recovery of copper from the acidic solution. Copper is plated on to titanium blanks using explosion-bonded crossrods, animal glue as a levelling agent, and an organic surfactant for mist control. The installation of the stripping machine in 2001 required a number of changes: cathode and anode contacts were redesigned, flat bus bars were replaced with dog-bone type, spacer boards for cathodes and anodes were installed, longer anodes started to be used, and the plating cycle was extended from seven to fourteen days. A number of initiatives for improvement are being carried out. Explosion-bonded crossrods are being replaced with titanium-clad crossrods. The plan for the near future is to increase copper production by increasing current efficiency and current density. The possibility of lowering the iron concentration in electrolyte and changing the acid mist control method is being investigated.

Jan 1, 2007

By J. Borlee, F. Sorrentino, A. Fleischanderl, M. Gimenez, W. Gebert, U. Gennari

Large quantities of solid by-products are generated by the steel industry and other important activity sectors in Europe (power plants, car dismantling companies, urban incinerators) with no or very limited potential for direct recovery. In the frame of a multi¬national project supported by the European Union, a consortium has been created to develop a treatment process able to turn these by-products into valuable metallic and mineral products. VAI has been responsible for the design, erection and start-up of the pilot plant for the new metallurgical process and for the execution of the test campaigns, with the targets defined together with the partners. Up to now, 9 campaigns comprising 60 heats have been performed successfully. By-products from C-Steel and stainless steel plants, as well as fly ash and auto shredder residues, have been used and defined products such as hydraulic binders for cement, metallurgical powders for De-S practice and recycled metal phase have been produced. The mineral products were positively assessed under industrial conditions. Results from cement tests and secondary metallurgy are reported, as well as a detailed characterization. The economic value of the products, credits from avoiding dumping and significant savings on CO2 emissions make the new process economically very attractive.

Jan 1, 2004

SOME months ago a Committee on Deep-level Mining was appointed [by the Government of the Union of South Africa] to consider the possibility of gold mining being carried on at a depth below 8,500 feet. The Committee consisted of Sir Robert Kotze (Chairman) , Mr. H. S. H. Donald (Government Mining Engineer), and Mr. H. R. Hill. The Committee has now made a report which was tabled in the House of Assembly on March 1st. The Committee reported that the tonnage of ore locked up in the deep level areas of the Central Witwatersrand is enormous, and in the 30 miles between Roodepoort and the East Rand Proprietory Mines has a value of about £200,000,000. The Committee says that, with good ventilation, the present system of wet mining, possibly with some modification and with the aid of refrigeration, may be carried to 10,000 feet, but that greater depths will require the adoption of dry mining. "A vigorous campaign of practical experiment into the possibility of dry mining should be initiated, and the Committee recommends to the Government the appointment of a committee of experts, consisting of representatives of the mining industry, the Mines Department, and the medical profession, with the Government Mining Engineer as chairman. The Committee suggests the provision of £30,000 for the first year for the investigations and experiments contemplated, which could best be carried out by an organization which might be styled 'The Rand Mining Research Institute' and constituted somewhat on the Jines of the South African Institute for Medical Research" . The Committee suggests that this committee of experts should arrange for experiments to be made with dry mining in one of the deepest mines, and investigate ventilation, refrigeration, support of workings, and the physiological problems connected with mining. "We emphasize the necessity of treating this whole question as one of importance and urgency. The investigations should be prosecuted with the utmost vigour and should not be delayed at any time for want of funds or for any other reason. If they are not done thoroughly and quickly, the whole scheme might just as well be left severely alone.

Jan 1, 1945

By J. B. C. Wu, B. McKee

"Mining along with subsequent processing of the minerals often presents conditions where a wear- and/or corrosion-resistant alloy is needed to minimize downtime and maximize efficiency. This paper is intended to give an overview of the alloys that are currently being used, as well as those developed in recent years that could be used in the mining industry. Emphasis will be put on the iron-, nickel-,cobalt-based alloys and composites containing a variety of carbides. The characteristics, properties, product forms, and methods of application are presented. In addition, examples of the actual use of these wear-resistant materials are illustrated.IntroductionPreventing wear and corrosion is important in any industrial operations. In the mining industry, the process equipment typically suffers many different types of material degradation. Abrasion, impact, erosion, metal-to-metal wear and corrosion are typically encountered. Each situation requires different material characteristics to retard the degradation process. Therefore, it is essential to understand the characteristics of the materials and the effects of the alloying elements.There are four common classes of metallic materials for resisting wear and corrosion; namely, iron-based alloys, nickel-based alloys, cobalt-based alloys, and carbide-containing composites. Each class of material has its own characteristics. Depending on the chemical composition, the materials within each class can be vastly different in properties. In recent years, there have been materials developed in each of the four classes using the knowledge of the metallurgical principles and the effects of the alloying elements on the material degradation process.To use a wear-resistant alloy, it is also necessary to understand the available product forms and their application methods. Weld overlaying is a traditional way of using these alloys (Wu and Redman, 1994). In recent years, thermal spray is becoming popular. For applications where over-laying and spraying are impractical, solid components can be made by a variety of casting and powder metallurgy techniques. They can also be fabricated from the wrought products.To select a proper material for an application, it is important to understand not only the characteristics of the wear-resistant materials but also the degradation process. Due to the complexity of the processing environments, past experience is also helpful in making the decision on the material selection."

Jan 1, 1997

At 14%, the representation of women working in the mining industry is the lowest among primary industry categories in Canada1. With reference to mining operations and senior leadership, the gap in the industry is even more pronounced. In an effort to narrow the gender gap, recent industry, education, and policy efforts have been made to increase the number of women entering the industry through career awareness and early career recruitment strategies. These strategies implied that by increasing the numbers of women entering the industry there would be a natural progression of women into the hierarchies of organizations. Efforts to retain women in the industry have focused around removing career barriers such as reviewing flexible work practices and programs directed at work life balance. At this time, these efforts have resulted in negligible fluctuations to the gender gap within the industry. This research investigates the under-representation of Highly Qualified Women (HQW), and the interaction of workplace culture on their career advancement and retention within the industry. HQW (women with a bachelor?s degree or higher) are the focus of the work as they represent an essential source of leadership and technical capacity for mining organizations. This paper is based on the results of a survey of 170 HQW working in the Canadian mining sector. The findings from this research suggest that HQWs careers in mining are stalled, despite a strong indication by respondents of interest in their professional career advancement. With regards to workplace culture, respondents indicated that blatant forms of gender discrimination have been reduced in mining workplaces; however, exclusion from informal networks, implicit bias and subtler forms of workplace discrimination persist. Utilizing a framework to assess the workplace culture for women in attracting and retaining their employment, respondents provided detailed information on the aspects of workplace culture that are most problematic in relation to women?s career development in mining. Women consistently identified problematic workplace culture as a significant barrier to the career advancement and retention of women within the industry. The representation of women within the labour force will likely remain stagnant until the industry addresses workplace culture within the industry, and makes strategic efforts to develop inclusive cultures throughout mining and supportive organizations.

Aug 1, 2013

By S. M. Taghavi, M. Halali

This paper investigates the possibility of zinc oxide production from zinc ore concentration residues, and also the effect of temperature, time and depth of bed on waste materials reduction percents. The results obtained show a significant increase of the reduction percent as a function of time and temperature. With increasing in depth of bed, reduction percent will decrease. Maximum zinc oxide percent in products was 93.5%.

Jan 1, 2004

By M. Bueno

Between 1993 and 2003, a series of AG and SAG mill pilot plant trials were conducted using Hardinge Ical pilot plant scale SAG mills on numerous ore samples and ranging across a wide variety of operating conditions. The data from these tests were used to evaluate the design of SAG and AG mill circuits for over a dozen projects, of which about half were eventually constructed and commissioned. The data were also used in the development of SAG mill modelling, scale-up and simulation procedures by several consultants who had access to part of the data set. Recently, we have had the opportunity to bring this data together and further analyse the consolidated dataset. This paper reports on the outcomes of this analysis that has identified the impacts of different AG/SAG circuit flowsheets and operating conditions on energy efficiency and operating cost.

Jan 1, 2012

During industrial copper electrowinning, a fraction of the electrolyte becomes entrained with the oxygen gas bubbles that are evolved at the anodes. The fraction of entrained bubbles increases from the bottom of the anode to the top, resulting in a bubble distribution that appears as an inverted wedge between the cathode and anode. Since the bubbles act as insulating spheres, electrolyte resistance increases from the bottom of the electrodes to the top resulting in correspondingly higher local current densities and uneven copper growth along the cathode. To counter-act the inherent tendency toward excessive copper growth near the bottom of the cathodes, the use of tapered anodes was examined. The potential improvement in cathode current distribution was evaluated by comparing the primary current distributions for 2-D computer models of a copper electrowinning cell with plate shaped anodes against one with tapered anodes.

Jan 1, 2007

By Paul D. Young, Michael J. Allan

"The Con Mine has been producing gold continuously since 1938. In 1990 laboratory and pilot plant investigations began into the use of pressure oxidation for treatment of an arsenic trioxide waste product from two previous roaster operations on the property. This led to the construction in 1992 of a 96 ton/day plant to treat a mixture of arsenic waste and flotation concentrate from the existing mill. The plant was commissioned in the fall of 1992.This paper describes experience gained in the commissioning and initial operation of the plant. The unique aspects of treating a hazardous waste product are described including special operating procedures to satisfy environmental and employee safety concerns. The paper further describes modifications made to the process flowsheet, to operating procedures and to materials of construction in the early months of operation."

Jan 1, 1994