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By W. R. Tyson

Pipelines for the transport of gas and oil are being designed to operate at increasing pressures in increasingly harsh environments. The steel used to construct these pipelines must have adequate toughness to tolerate weld imperfections (i.e. withstand bending strains) and to arrest running cracks (i.e. to prevent propagation of axial fractures). The problems posed in specifying suitable toughness parameters and the approaches currently being used to measure them are discussed.

Jan 1, 2005

By Helmer Kraemer

One of the CIM 2003 conference themes is ?Globalization and the impact on mine operations?. In this context, the first official version of the new ?International Rock Excavation Data Exchange Standard? (IREDES) is being released. This new standard is a highly flexible data interface for exchange of information between production equipment and central computer systems. The standard was defined by global players in the mining industry and will soon be used to enhance local operations of global mining companies. Beside the standard definition now other aspects are coming into focus: The question how to design and how to implement IREDES compliant data exchange in practice. Implementation of IREDES covers the following aspects: !" Implementation on in-field production systems !" Communication and networking !" Implementation on databases and commercial IT systems In-field production systems are characterized by a big variety of different automation systems. Therefor, different IREDES implementation philosophies have to apply to those systems. One philosophy uses an integrated IREDES compliant automation system on every machine. The alternative method uses one shared IREDES compliant ?Proxy server? for a number of machines connected to this server using proprietary interfaces. Communication and networking can be integrated openly and independently from hardware infrastructures. The only precondition is that communication and networking has to be Ethernet - TCP/IP protocol compatible. IREDES Implementation on the commercial IT level means to exchange IREDES data sets with databases, simulation software, office packages and special applications. Interfacing is easy as long as the software or the database system provides an interface to the Extensible Markup Language (XML).

May 1, 2003

By V. A. G. Preto, W. H. White, J. E. Harakal

Potassium-argon age dating performed recently on intrusive rocks from Copper Mountain indicates that the satellite Smelter Lakes and Voigt stocks have radio-metric ages which are indistinguishable from that of the Copper Mountain stock, as determined by Sinclair and White (1967). The complex of intrusive rocks known as the Lost Horse Intrusions also yields essentially the same radiometric age, as do biotite-sulphide-pegmatite veins on Copper Mountain.

Jan 1, 1971

From 1999 to 2008 rock related accidents accounted for 75 fatalities, nearly 6,000 injuries and almost 14,000 incidents (Pappas and Mark, 2011). Clearly this shows that rock related safety on coal mines remains a serious issue and more effort is needed to address this hazard. This paper reviews support design considerations and monitoring needed to improve rock related safety in room and pillar coal mines in the USA. From the present study design considerations continue to evolve and improvements in technology and a better understanding of failure mechanisms and methods to prevent these failures from occurring are in place. At first glance, the design of safe and efficient underground openings appears simple until the designer begins to realize the complexities and variability of geometries, geology, loading and stress influences, support designs and other factors such as corrosion and economics. Ultimately the goal of all designs is to ensure that it can be completed safely, last for the duration of the design life and it is economically feasible.

Aug 1, 2013

By J M. Gibbs

Craigmont Mines Limited mine 50,000 tons of ore and waste per day from the open pit at Merritt, British Columbia. An electric-powered "down-the-hole" drill, a diesel-powered rotary drill and two electric-powered rotary drills have been used. All primary drilling, as a result of cost and operating experience, is now performed with two electric-powered rotary drills. Trials with various loading techniques have increased the amount of AN-FO and decreased the amount of commercially prepared slurries used for primary blasting. Approximately 95 per cent of the primary blasting is accomplished with AN -FO, mixed at the hole. Introduction THE Craigmont mine is located near the village of Merritt, B.C., 240 miles northeast of Vancouver. The concentrator has been in production since September of 1961. Craigmont is a combined open-pit and underground operation. To date, slightly more than 95 per cent of the mill feed has been mined from the open pit. As underground development proceeds, the ore requirements from the open pit will decrease. The average milling rate from September, 1961, to April, 1964, was approximately 4,900 tons per day.

Jan 1, 1965

By J. M. Mwase

The platinum group metal (PGM) industry is currently reliant on the crush-mill-float-smelt-refine route to process PGM ores. However, there are many instances where this route would not be feasible. An alternative process route has been developed which involves heap bioleaching to extract base metals followed by heap reclamation and a water wash step, leading into heap cyanide leaching to extract precious metals. This process was evaluated through test work on samples of Platreef ore using laboratory scale columns. After 304 days 75% Ni and 93% Cu were extracted in the bioleach experiment at 65°C, and after 60 days 58% Pt, 99% Pd and 90% Au in the follow-up cyanide leach experiment at 50°C. A preliminary process flow sheet has been developed around this. Analysis via a mineral liberation analyser showed that the remaining Pt was in the form of the mineral sperrylite, which appeared to be slow leaching in cyanide in comparison to the other mineral types. Analysis of cyanide effluent solution showed high levels of thiocyanate, which present an environmental risk for disposal and high consumption of cyanide. Further studies to develop the process for commercial application in the South African PGM industry are outlined.

Jan 1, 2014

By C. Schlumberger

INTRODUCTION The object of the present paper is to discuss, from a geological point of view, the practical results obtained by the authors with the method of the 'resistivity map of the subsoil' in the study of various mining problems. Some of the studies described date from 1920, 1922, and 1923. They are, therefore, quite old, at least as far as geophysical research is concerned (1). Others, on the contrary, are very recent (2). We shall deal only very briefly with the theoretical and technical sides of the processes employed. This paper has, essentially, a practical purpose, and it has seemed unnecessary to enter into a detailed discussion of the methods. Such a discussion cannot be presented without introducing ,quite. Complex considerations both of mathematics and experimental physics, which interest only the geophysicist: whose work is highly specialized.

Jan 1, 1931

By L. C. Johnston, J. N. Gills

This paper reviews the basic reactions of the blast furnace and the open hearth furnace, and then discusses the quarrying and sizing requirements of the limestone feed for each. Particular emphasis is placed on the lime-stone at Irish Cove, now being mined under an agreement between Scotia Limestone Limited and Dosco Steel Limited. The drilling and blasting operations are described, along with loading and haulage, plant flow, water supply, power supply and transportation facilities.

Jan 1, 1967

By A. Danaei, A. McLean, M. Barati, C. Ravindran

"The aluminum industry generates about 90 million tonnes of red mud each year. Previous research shows it could be utilized as a refining flux with a high capacity to absorb phosphorus and sulphur from hot metal in the steel industry. The present study was undertaken to evaluate the melting properties of such fluxes, as it affects the effectiveness of the flux. The results show that the melting behavior of red mud is strongly affected by lime addition and the characteristic melting/softening temperatures reach minimum VALUES (at 32.7 wt% CaO. From these findings, a correlation was established between melting behavior and optical basicity. This allows one to adjust the composition of the flux based on the process requirements. INTRODUCTIONThe aluminum industry generates about 90 million tonnes of bauxite residues each year. This residue is usually red in color because it contains a substantial amount of iron oxide. The red mud, as it is called, is a solid waste with a high concentration of sodium oxide, high pH (10 to 13), and high alkalinity, and thus is harmful to many forms of life. Traditionally, the material is stored in large tailings ponds within the plant’s vicinity (Power, Grafe, & Klauber, 2009). Development of solutions for safe disposal or preferably using this residue for other industrial processes or applications could help restore polluted locations and eliminate a negative impact on the environment (Haake, 1988; Power et al., 2009; Yan & Xuegong, 2010).The mineralogy and chemical composition of red mud depends on the quality of the bauxite and refining process parameters. In general, it consists of iron oxide (Fe2O3), aluminum oxide (Al2O3), titanium oxide (TiO2), sodium oxide (Na2O), silicon oxide (SiO2), and calcium oxide (CaO) (Power et al., 2009). Like most ores and soils, bauxite can contain trace quantities of metals such as arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and naturally-occurring radioactive materials, such as thorium and uranium. Most of these trace elements stay in the residue (Power et al., 2009)."

Jan 1, 2012

By A. J. Naldrett

"Sulphurization of peridotite, that is 'to say reaction between sulphur from an external source and iron and nickel in the silicate minerals of the peridotite or in partially consolidated magma, is believed to be the me-chanism by which the small iron-nickel sulphide deposits associated with the ultrabasic rocks of the Porcupine district have formed.The pyrrhotite-pentlandite ore at the Alexo mine, Dundonald township, is localized by a shear that closely follows the lower contact of a peridotite lens. In the past, to account for this orebody, the magmatic segregation hypothesis has been advanced on the basis of textural evidence and the presence of the sulphides at the base of the lens. The nickel sulphide de-posits of the Porcupine, however, are not characteristically found along the basal contacts of bodies of peridotite. Furthermore, this study has shown that textures formerly thought indicative of magmatic segregation have been formed in certain deposits by the selective replacement of silicates by sulphides.At the Alexo mine, very minor amounts of pentlandite and heazle-woodite (Ni3S2) occur in the peridot-ite hanging wall adjacent to the ore. These sulphides are interpreted as having formed by sulphurization, the sulphur involved coming from the pyrrhotite-pentla.ndite ore emplaced along the shear. This reaction aureole raises the question of the role of sulphurization in the formation of the main mass of the sulphide ore. The very localized equilibrium that has been found to exist between sulphides and silicates in deposits throughout the area, the results of nineteen sulphur isotope determinations, and the abundance of pyrite and pyrrhotite in the volcanic country rocks of the Porcupine indicate that these deposits were formed by sulphurization rather than magmatic segregation."

Jan 1, 1966

By C. Fortin

The subject of gold flotation has been reviewed extensively in a number of publications. The focus in most of these reviews has been on the theories of gold flotation as well as the physical and chemical effects that may impact the efficacy of the gold flotation process. It is evident that the current status of gold flotation chemistry as it is being applied in industry has not been addressed widely. It is the intent of this paper to review current gold flotation practice and how these applications tie in with the current understanding of the chemistry of gold flotation.

Jan 1, 2011

By N. A. Warner

Virtually zero gas emission smelting is promoted as a means for securing environmental advantages and the general public’s acceptance. Concerns about climate change will increasingly make it more difficult for new primary metals projects to come to fruition unless greenhouse gas emissions are decreased. Assuming a sustainable market for sulphuric acid is not locally available, the next best option is high temperature reaction of strong SO2 with limestone or dolomite. This is followed by CO2 liquefaction and disposal either underground or in the deep ocean. The Voisey’s Bay nickel project is cited as an example where appropriate location of a new smelter close to large dolomite or limestone deposits would lead to a virtually zero gas emission operation. Most of the electrical energy required for producing technically pure oxygen and for liquefying CO2 and transporting it to disposal can be derived from smelting a bulk sulphide concentrate and then reacting SO2 at high temperature. Provided the smelter gases are properly cleaned before sulphur fixation, the sulphated stone should be uncontaminated and environmentally benign and possibly of use in the building and construction industry.

Jan 1, 1999

By D. Furrer, M. Dallaire

The arrival of Image analysis in the last 20 years has changed the world of quantitative metallography. Many standard measurement techniques which were previously manual can now be done with fully automated systems. This reduces subjectivity and operator fatigue and therefore enhances the quality of the statistical results. In many laboratories, Titanium Alloy microstructures continue to be evaluated by traditional methods, where quality of results is subject to operator fatigue and level of experience. Advances in Camera technology have tremendously improved image acquisition. One can often see clearly at 500x what can not be observed at 1000x, allowing for a larger area to be analyzed, without the inconveniences associated with very high magnification objectives. Powerful and versatile Image analysis software combined with a high precision motorized stage gives access to a multitude of applications, which were extremely challenging or impossible until now. Image Analysis tools such as Multilayer Grab, which reconstructs an uneven image into one plane of focus (ex. Observation at high magnification of texture resulting from etching) and Mosaic which builds an image from a number of fields of view (ex. Reconstruction of very large grains at low magnifications) expand even further the power and flexibility of IA systems. This presentation will describe how automated methods are applied to the point count method and grain size measurement. We will show how cameras and software work together to permit quantitative measurements of primary alpha and prior beta microstructures, as well as lamellar alpha plate thickness in titanium alloys.Automated and semi automated quantitative measurements of various Titanium microstrures have been assessed, using the Clemex Vision PE. Examples of the methods and steps used are presented.

Jan 1, 2006

By B. McKevitt, P. Abbasi

The ion exchange process (IX) is applied in the mining industry for the removal of impurities from process streams, treatment of waste solutions prior to disposal and the recovery of valuable metals. Extensive studies have been performed with the goal of modeling of IX for the case of a single metal loading onto iminodiacetic resin in the hydrogen form. However, in a real system, a resin may be saturated by impurities (iron, calcium, magnesium, manganese), which are then displaced by the metal of interest. The present study provides an insight into the Fe2+ loading process onto iminodiacetic ion exchange resin under the infinite solution volume condition. The study involves the measurement of iron loading under a variety of experimental conditions as well as an attempt to model the loading process using the hybrid correlation advanced by McKevitt (2012). The importance of the experimental and modeling work are discussed in the context of resin in pulp recovery of nickel.

Jan 1, 2014

By Junior Santos

Kinross Paracatu started the operation of the new gold processing plant in the end of 2008, being composed by one SAG mill and two ball mills. During the first year of operation the plant had several problems related to stability and throughput capacity, mainly due to low grinding efficiency of the ball mills. In this period many actions were taken to maximize the throughput rate. Among the actions are reducing the size of balls in the mills, increasing the ball charge in the SAG mill, changing cyclone configuration and return of circulating load to SAG mill. With better stability of the circuit, the second stage of improvements has begun with the objective of increasing throughput rate and also reducing operation costs. Among the actions are the optimization of ball charge in the mills and a better operational control of cyclone parts. After two years of operation was obtained a significant increase in plant capacity, but still requires the addition of a third ball mill in order to maximize the use of SAG mill, which has spare capacity.

Jan 1, 2012

By Grant Small, Jessica Kinal, Christopher J. Greet

"The conversion from an electrochemically reactive grinding media (forged steel) to a more electrochemically inert alloy (high chrome white iron) not only reduces the wear rate of the grinding media, but also has an impact on the grinding chemistry. Typically the grinding chemistry becomes more oxidising, with less reducing Eh values and more dissolved oxygen in the pulp. There is also a decrease in the EDTA extractable iron, which is an indication of the change in the media corrosion. These changes are indicative of alterations in the surface chemistry of the minerals that the operator is trying to separate. For porphyry copper ores the changes in the pulp and surface chemistry not only affect the copper sulphide minerals, but also impact the iron sulphides (i.e. pyrite and pyrrhotite). Generally, with more oxidising pulp chemical conditions during grinding there is an increase in the oxidation of the iron sulphides which renders their surfaces hydrophilic, thereby depressing flotation. This leads to improved selectivity for copper sulphides against iron sulphides.INTRODUCTIONPorphyry copper deposits are the dominant source of copper that is mined today to satisfy global demand. These style of deposits typically contain one percent copper mostly as chalcopyrite, but may contain other copper bearing minerals (for example, bornite, chalcocite, azurite, malachite), small quantities of pyrite and quartz. Porphyry copper deposits also contain economically significant quantities of gold, silver and molybdenum. Interestingly, the majority of the world’s porphyry copper deposits are concentrated along tectonic plate boundaries (Figure 1)."

Jan 1, 2016

By Darryel Boucher, Thomas W. Leadbeater, Raymond Langlois, Joshua Sovechles, McGill University, Zhoutong Deng

"Spiral concentrators are used to upgrade ore based on the density difference between their component minerals. This simple flowing film gravity separator is of interest for the processing of large amounts of material, as found in the iron ore industry. Addition of wash water at different points on the trough of the spiral affects the grade and recovery of the valuable concentrate by affecting the flow of particles within the thin slurry film. This paper shows how radiolabelled hematite (-355+300 µm) and quartz (–1,180+1,000 µm) tracers were used to determine the particles’ behaviour within the slurry film with and without the addition of wash water. The results presented provide a detailed particle flow pattern around a wash water addition point and its effect on the trajectory and velocity of the particles. This information is of interest in building knowledge about spiral wash water injection parameters such as injection location, direction, flow rate and nozzle orifice type (affecting jet shape and velocity).INTRODUCTIONSpiral concentrators are density based separation devices. They are extensively used in the upgrading of iron ore, fine coal and minerals sands (sources of ilmenite, rutile, zircon and monazite) (Wills & Finch, 2016). A spiral unit is composed of a channel of specific profile formed as a helix of 3 to 7 turns around a central structural post. The feed pulp is composed of 15 to 45% solids with particle size from 75 µm to 3000 µm (Wills & Finch, 2016). Throughput of a single spiraling trough can be up to 8 ton per hour and multiple trough unit (up to four trough) can process up to 30 ton per hour for a footprint of around 0.7 m2 (Palmers & Vadeikis, 2010). They are low cost concentrators considering manufacturing of their trough via polymer reverse molding. The energy intensity of a spiral plan is notably small considering the throughput and is mostly related to pulp pumping and final concentrate dewatering."

Jan 1, 2016

By J R. O Walli

Large production shafts can be successfully sunk through the ubiquitous Blairmore formation of southern Saskatchewan by employing the freezing process and by the installation of a cast iron tubbing lining. Although the freezing technique for shaft sinking and the use of cast iron tubbing to preserve the shaft are new to the North American continent, these procedures have been employed in Europe for the past eighty years. More than 200 shafts, covering a wide variety of ground conditions, have been sunk by the freezing process, and most of these have been lined with cast iron tubbing. The No. 1 shaft of International Minerals and Chemical Corporation, near Esterhazy, Saskatchewan, comprises the first major example in Canada of the employment of European methods to overcome extremely difficult ground conditions. The Blairmore formation was solidified by the deep freezing process, employing a lithium chloride solution as the refrigerant, with input temperatures ranging to -55°F

Jan 1, 1964

By M. Dadvand, G. Kipuros, A. Dadvand

"The ability to codeposit fillers within a nickel matrix has led to the production of a new generation of cermet coatings with properties useful for various applications. Hexagonal boron nitride (hBN) is a ceramic-type particulate matter with thermal conductivity, thermal stability, inertness, and lubricity properties that allow it to be codeposited. In this paper, a method was developed for modifying hBN surfaces to allow them to be uniformly dispersed in water-based solutions such as an electroless nickel plating bath. hBN surface modification improved wear performance of the electroless plated cermet due to enhanced interaction between the particulate and nickel matrix. RÉSUMÉ La capacité à effectuer un dépôt simultané de charges dans une matrice nickel a abouti à la production d’une nouvelle génération de revêtements cermet (une combinaison de céramique et de métal) dotés de propriétés très utiles pour diverses applications. Le nitrure de bore hexagonal (h-BN) est une matière particulaire de type céramique utilisée pour ses excellentes conductivité et stabilité thermiques, son inertie ainsi que son caractère lubrifiant, qui permettent son dépôt simultané. Cet article explore une méthode mise au point pour modifier les surfaces du h-BN de manière à ce qu’elles se répandent uniformément dans des solutions aqueuses telles qu’un bain de dépôt autocatalytique de nickel. La modification des surfaces du h-BN a amélioré la résistance à l’usure du placage autocatalytique du cermet en raison d’une interaction accrue entre la matière particulaire et la matrice nickel.INTRODUCTION Electroless nickel alloy coatings can be used for many applications; however, the need for improved tribological properties such as higher wear resistance and better lubricity has increased interest in incorporating particulates (fillers) into the nickel matrix by codepositing the particulates with nickel during the plating process. The selection of the particulate type depends on the desired properties (Sahoo & Das, 2011; Sudagar, Lian, & Sha, 2013). In terms of tribological applications, electroless nickel-based composites are categorized mainly into lubricating and wear-resistant composite coatings depending on the type of particles incorporated. The electroless nickel-phosphorus (Ni-P) composite coatings are composed of codeposited solid lubricants such as polytetrafluoroethylene (PTFE), graphite, WS2, MoS2, and hexagonal boron nitride (hBN) and, compared to nanocomposite electroless Ni-P coatings, they demonstrate a lower coefficient of friction. On the other hand, the nickel-phosphorus wear-resistant composite coatings are composed of hard particles such as silicon carbide (SiC), aluminum oxide (Al2O3), boron carbide (B4C), silicon nitride (Si3N4), diamond, tungsten carbide (WC), and zirconium oxide (ZrO2) and, compared to nanocomposite electroless Ni-P coatings, they have higher hardness and better wear resistance (Sahoo & Das, 2011; Sudagar et al., 2013; Parucker, Klein, Binder, Ristow, & Binder, 2014; Chakarova, Georgieva, Petrova, Dobreva, & Stoychev, 2016)."

Jan 1, 2018

By M. E. Bilir

In this paper, we review cases in which dramatic and visual swelling problems are experienced in underground structures. Swelling rocks have caused many problems in underground engineering projects. They pose severe problems to the design, construction and maintenance of underground openings. If an appropriate integrated design procedure, which proceeds from exploration, tests, analyses and realistic assumptions of swelling behavior, is used during the design stage, the execution of the project can be completed without any serious delays or dramatic design changes. The case histories were subdivided into three classes that include tunnels, underground coal mines and others. For the evaluation of cases, the surrounding rocks, swelling minerals, water inflow, swelling test results and swelling problems were considered. The main purpose of this review is to inform the reader about potential problems with swelling phenomenon and to emphasize the rehabilitation and extensive cost which are encountered due to the lack of necessary integrated design approaches.

Aug 1, 2013