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By Nelson C. White

This paper summarizes the present state and future prospects of the potash industry, with special reference to its impact on production in Saskatchewan.

Jan 1, 1968

By Adrian White

Agenda Overview of pastefill at Kidd Mine Pipeline wear and the need to monitor Steel Loop monitoring Steel Borehole monitoring Monitoring pipe linings

May 1, 2013

By M. Bozorgtabar

Metal Matrix Composites (MMC) have a ductile matrix containing ceramic particles, Due to their improved wear properties, Al?SiC composites have economical applications in many industrial uses where wear is a problem, One of the most serious difficulties in manufacturing Al-SiC composites is obtaining adequate 'wetting' of the particles by the melt. In this research work, a stir casting system was designed for the improved manufacturing Al-SiC composites, The effect of some production variables such as the addition of SiC particles to the aluminum melt on wettability, was also studied. The results showed that the manual addition of particles would not be successful in manufacturing and that a system of adding silicon carbide particles through controlled temperature, atmosphere and improved mixing was needed.

Jan 1, 2005

By P. Hale

"The trend to drives of more than 10,000 hp on large-capacity ball and autogenous mills for increased operating efficiency has been limited by factors in the conventional drive system. A solution to this problem, using modern developments in static converter technology, is the concept of driving the mill directly without gearing using a low-speed, low-frequency synchronous motor with a cyclo-converter power supply.This paper presents various practical arrangements of mill and low-speed motors giving the specific advantages of each system. The means of controlling inrush currents on starting and of spotting by the use of variable-frequency control are outlined in general form. Several gearless ball mill drives are scheduled for start-up in European cement plants and further orders have been placed."

Jan 1, 1970

By R. Minto, W. G. Davenport

The slag removed from the reverberatory furnaces of copper smelters contains significant copper values. A serious financial loss is involved, as further recovery operations are not normally carried out. This paper describes the factors affecting physical transport of matte into slag by gas bubbles, and the subsequent entrapment and flotation of matte drops. Three distinct patterns of transport behaviour have been identified from studies of a number of liquid/liquid systems, including liquid metal and liquid matte systems. A theoretical approach is proposed to explain these behaviour patterns, and to predict transport and entrapment behaviour in matte/slag systems. The concepts of "Film Coefficient" (ø) and "Flotation Coefficient" (?) are introduced. The effects of smelting process variables on the physical loss of copper matte in slag are also discussed.

Jan 1, 1972

By J. Marks

The measurement of greenhouse gas (GHG) emissions from primary aluminium production and inventory of these emissions of carbon dioxide and PF Cs have become an important issue for primary aluminium producers. Most global producers have either voluntary emission goals or emissions limits established through national regulatory requirements. International good practices for inventory of these emissions for national governments are established through the Intergovernmental Panel on Climate Change (IPCC). The current good practices, last updated in 2000, are being revised and are expected to be adopted by governments in the spring of 2006. There are a number of changes expected in the guidance that will impact how facilities account for their GHG emissions. This paper describes the changes to the guidance and the implications of these changes for aluminium producers.

Jan 1, 2006

By A. Hosseini

Full-scale rupture tests were conducted on 508 mm (20 in) diameter API X-60 5.7 mm wall thickness pipes containing either axial semi-elliptical cracks or simulated corrosion defects with equivalent depths ranging from 20 to 60 percent thickness. In the case of the cracks, the failure pressures were predicted with reasonable accuracy when considering a level 3 failure assessment diagram (FAD) procedure based on API 579, as compared to level 2 FAD, since the mechanical properties were known. In both cases, the accuracy improved for shallower cracks. Considering simulated corrosion defects, the RSTRENG approach provided more reliable results on predicting the collapse pressure. For a similar depth and profile, the cracked pipes failed at a lower pressure than those containing simulated corrosion defects of equivalent depth.

Jan 1, 2010

By S. Yue, P. Vo, M. Jahazi

The flow behaviour and microstructure development of a near-alpha titanium alloy during beta working has been investigated. Typical cogging conditions were simulated through compression testing of IMI834 at temperatures of 1025°C-1100°C, strain rates of 0.01 s-1 - 1 s-1 and post-deformation heat treatments up to 4h. Using a synthesis of available literature models, a finite element model has been developed and validated through quantitative measures of flow stress-strain data and beta grain characteristics. Flow behaviour was analyzed through a self-consistent method while the microstructure development was considered with regard to the kinetics of beta recrystallization. Deformation at beta or high alpha/beta working temperatures (T>l025°C) produced minor flow softening with complete grain refinement achieved through metadynamic recrystallization.

Jan 1, 2006

By A. Chaisantikulwat

Most solid-oxide fuel cell (SOFC) modeling emphasizes steady state cell operation. However, understanding the dynamic behavior is essential to predict the performance and limitations of SOFC power systems. In this work, we demonstrate a dynamic model of a SOFC, and we simulate a feedback control scheme that can maintain output voltage despite load changes. Dynamic response is determined as the solution of coupled partial differential equations derived from conservation laws for energy, mass and electric charge. From such a model, the step responses to system input variables can be determined. Low order dynamic models that are sufficient for feedback control design can be derived from the step responses. The development of the partial differential equation model is outlined, and the limitations of the control system are discussed.

Jan 1, 2005

By S. Gößling-Reisemann

Most copper ores contain valuable co-products such as molybdenum, gold, silver, nickel, etc. Sulphuric acid and steam are valuable by-products, which are generated dur¬ing copper production. The environmental impacts from mining and refining therefore need to be shared between these by-products and co-products, an issue in Life Cycle As¬sessment (LCA) referred to as allocation. There are different, recognised methodologies for doing so: burdens can be allocated based on the market values of these commodities, they can be allocated by mass, volume, molar amount, functionality, or other physical, technical or economic factors. All of these methodologies have their respective merits and restrictions, and the choice is usually case specific. Nevertheless, the choice between alternative methodologies can have dramatic effects on the LCA results. Recycling in LCA has to be handled in a similar way, as it essentially constitutes a special case of co¬production. The existing standards (ISO 14040 ff.) allow different methods for imple¬menting recycling and allocation into metal LCAs (open loop, closed loop, value cor-rected substitution, etc.), which are still a subject of discussion in the scientific community. However, the methodology used can significantly influence the ecological profile of copper and copper products. We will present an overview of the different methodologies available for including recycling and allocation and give an analysis of how the meth¬odological choice affects the final LCA results. This work will be followed up by quantitative case studies.

Jan 1, 2007

By John H. Low

Introduction Despite the fact that the .association of magnetite with chrysotile asbestos in the parent producing area of the world, the Thetford Mines - Black Lake area, has been recognized since the ores of that region were first known, magnetic methods were not extensively employed in exploration for asbestos until about the beginning of 1949. Since then, large areas of Ontario, Quebec, and the eastern United States have been prospected both by aeromagnetic and conventional ground magnetic methods. Prior to 1949, a limited amount of magnetic work had been done, notably that of A.H. Miller (1, pp. 184-186), which was carried out in conjunction with the geological survey of the Thetford area by H. C. Cooke (2) in the years of 1930 to 1932. At that time, Miller pointed out that the occurrence of asbestos is associated with very large magnetic 'anomalies' and that, within the Pennington dyke, an area of asbestos- bearing peridotite could be distinguished, by the anomalies, from adjacent areas of non-asbestos ?-bearing peridotite. Since he .also observed large anomalies in what were believed to be ?barren areas, Miller concluded, however, that the magnetometer could hardly be of much or any value in the direct location of asbestos War .and post-war demands on known reserves of asbestos ore, however, stimulated the search for new deposits, and an economical and rapid method of directing speculative drilling was most desirable.

Jan 1, 1951

By Kwang-Hyun Jeon

Recently, 3D printing technology in the manufacturing field is in the spotlight. In the construction industry, similar rapid prototyping technology that does not use conventional form can be applied to meet the demand on free formed structure that can provide aesthetic value and functionality. Conventional formwork can increase construction cost and period for various structure with complex shapes while it has numerous advantages such as high strength, convenience, accuracy and good quality of surface roughness. To meet the demand on free formed structure, automated freeform construction systems such as Contour Crafting and Concrete Printing have been developed with active collaboration between university and industry in USA and England. However, details on the system have not been fully released in public, so the possibility of its fusion and spin-off technology cannot be expected. In this paper, cost-effective solution for mechanical and control system for constructing a free curved structure without mold are described. As an appropriate material for the system, fiber reinforced mortar was selected by experiments on compressive strength, setting time and fluidity. After performing G-code simulation, transfer and extrusion experiments with the selected mortar mix were performed and the possibility of the development of automated freeform construction system was demonstrated. Based on this research results, it is required to keep the automated freeform construction system improve and extend it into the new application area in construction industry.

Aug 1, 2013

By D. MOORE, A. REINSBAKKEN, A. J. Sinclair

The Gypo quartz vein lies near Oliver, British Columbia, and was quarried between 1955 and 1968 for decorative chips. The vein is one of many quartz veins hosted by the Late Jurassic Oliver Plutonic Complex, specifically by the porphyritic quartz monzonite phase of the pluton. The vein has a known length of 155m and a thickness of 46m. It strikes east-west and dips at 60 degrees to the south. Mineralogy is predominantly quartz with minor pyrite, muscovite, fluorite, calcite, apatite and manganese; trace amounts of chalcopyrite, pyrrh otite, marcasite and molybdenite also are present. Quartz in the vein is zoned. A thin grey quartz zone found near the margins of the vein fades gradually into white quartz, which comprises over 95% of the vein. Late-stage boxworks cut earlier mineralization, particularly fluorite, which occurs as pods in a zone fairly close to the hanging wall. Sulphide minerals are found in a centrally located zone in the quartz vein. The hanging wall of the Gypo veins is altered only slightly, but thefootwall is altered extensively to a greisen of muscovite and grey quartz. Evidence suggests that early in rhe vein development, the adjoining country rock was feldspathized. As grey quartz and muscovite was deposited, a period of intensive greisenization and fracturing occurred which so weakened the rock that a central block of greisenized country rock foundered. This provided the open space in which the vein was deposited.

Jan 1, 1984

By Y. O. Fortier

"ForewordTHE Arctic Archipelago and northern Greenland contain an orogenic region that is as much as 300 miles wide and over 1,400 miles long. It occupies much of what was formerly classified with the Arctic Plains and grouped with other plains and lowlands of Canada as one main geological division. It is proposed that this folded region be designated the Innuitian Region and be recognized as one of the main geological divisions of Canada.Canada's main geological divisions (see Geological Survey of Canada, 1947) have been considered as consisting of a central shield, largely surrounded by plains that separate it from eastern and western mountains. The plains include the Interior Plains, the St. Lawrence Lowlands, the Arctic Plains or Low-lands, and the Hudson Bay Lowland, which is in the central part of the Shield. Plains and mountains are, strictly speaking, physiographic terms, but because mountains are generally folded regions and plains are generally made of undisturbed strata, such terms are useful vehicles to express the fundamental make-up of the land. Nevertheless, it is preferable to use the terms Appalachian and Cordilleran 'Regions' rather than 'Mountains', as those geological divisions are not exclusively made of mountains.Because of the lack of more definite information, the 'Arctic Plains' have included, in the past, regions with plateaux two to four thousand feet above the nearby sea, mountain ranges reaching approximately 10,000 feet above sea level, and regions of folded strata."

Jan 1, 1955

By Ibrahim Ocak

The prediction of machine utilization time and determining machine performance plays an important role in scheduling and planning tunnel excavation and data base created serve a major role in further applications. In this study, the construction methods of two twin tunnels situated between Basak Konutlari station and Istoc station are summarized. Geology in the study area is composed of fill and weak rock, respectively starting from the surface. The tunnels of 5.6 km in length were excavated with two different earth pressure balance machines (EPBM). Excavation diameters of the EPBMs were 6.564 m. The performance of the machines are analyzed and compared in order to accumulate data for further applications in similar ground conditions in Istanbul. The distance between two twin tunnels is 14 m from center to center and the EPBM in the one tube was almost about 100 m behind the other tube. Segmental lining with 1.4 m of length and 30 centimeters of thickness were used as final support. The overall performances of the two Lovat TBMs are found to be respectively as; the best daily advance rates 30.8 m/day and 30.8 m/day, the best weakly advance rates 115.0 m/day and 153.9 m/day, the best monthly advance rates 388.7 m/day and 400.5 m/day. Total waiting and maintenance times were 25.2 and 16.7 %, respectively.

Aug 1, 2013

This paper examines the latest advances in mine hoist motor and drives systems. The technology employed for large hoists has migrated from the traditional DC technology to AC motors with cyclo convertor drives, and more recently, advances in pulse width modulation (PWM) drives have resulted in these being applied to large hoist drives. When combined with PWM drive technology, the induction motor presents the ideal solution for hoist applications This paper examines the factors in choosing a suitable PWM drive and motor for a hoist installation. Factors under consideration include: ? hoist duty cycle, ? drive rating restrictions, ? choice of power semiconductor device,, ? low speed operation, ? maintenance ? reliability The cage induction motor and synchronous motor are compared and it is shown that the induction motor is the motor of choice for large hoists.

May 1, 2010

By E. Czech

Hydrogen generated through aluminum-assisted water split reaction is a novel, efficient and environmentally friendly method. It has been found previously that the passivation of aluminum can be prevented in neutral (pH=7) or near neutral pH conditions in water by grinding aluminum with a catalyst, such as A12O3, SiO2 or SiC. Recently, the best results have been obtained by using water-soluble inorganic salts (WIS), ground with aluminum. The massive, rapid corrosion reaction of the Al-WIS system which takes place in regular tap (or marine, or ground) water can be utilized to produce hydrogen by aluminum-assisted water split reaction, in-situ, on-demand. The reaction offers clean, low-cost, environmentally benign and entirely recyclable technology for on-board on-demand hydrogen generation. Besides pure gaseous hydrogen, only pure solid aluminum hydroxides AlOOH or Al(OH)3 are formed as the reaction products. The hydrogen yield and Al-WIS reaction efficiency are high. From 1 g of mechanically alloyed aluminum powder, up to 1.25 liters of hydrogen were generated, i.e. efficiency up to 92% was achieved. The amount of hydrogen and hydrogen generation rate depend on various reaction parameters. The effect of chemistry and concentration of additives, water temperature, powder particle size and milling conditions on the reaction kinetics will be presented and the possible process mechanism will be discussed.

Jan 1, 2005

By R. Ham-Su, J. P. Healey, S. P. Farrell, R. S. Underhill, M. A. Gharghouri, C. V. Hyatt, L. M. Cheng

Magnetic shape memory alloys (MSMA's) are a class of materials where magnetic energy can be converted into mechanical energy and vice versa. NiMnGa-based MSMA's have attained magnetic field induced strains up to approximately 10% and have a relatively wide operating temperature range, from well below 0°C to above RT, making them very attractive for a variety of applications. However, these materials also suffer from low toughness. Using these materials in a composite could mitigate this shortcoming, and also overcome limits imposed by inertia and eddy current losses. In this work, we describe the manufacture and characterization of such composites. Composites with 30% by volume MSMA were fabricated under a magnetic field resulting in anisotropic magnetic properties. Damping properties were evaluated by dynamic mechanical analysis.

Jan 1, 2004

By A. Valenzuel

Arsenic is a common impurity in copper sulfide concentrates treated pyrometallurgically, which inevitably during the smelting-converting process reports in the final copper product affecting its properties, but also it is a very toxic occupational hazard. Arsenic recovery or disposal from concentrates or arsenic-containing copper smelter dusts have been practiced in the metallurgical industry for many years. It has been recovered principally as arsenic trioxide by roasting or leaching then precipitated. On the other hand, several hydrometallurgical processes have been developed and implemented in smelters to remove it from arsenicbearing dusts and stabilize it prior to disposal in the form of a solid compound, either as calcium arsenate, arsenic sulfide or ferric arsenate. This paper reviews the methods implemented for arsenic recovery worldwide and arsenic disposal in the metallurgical industry.

May 1, 2001

By Edward R. T. Tiekink

Metal complexes continue to find therapeutic applications for the treatment of a wide variety of human ailments. Amongst these, gold(I) thiolates are used to treat rheutmatoid arthritis but, usually in combination with other treatment or as a last resort. New therapeutic uses of gold, both as gold(I) and gold(III), are being sought, including against cancer, the focus of the present contribution. It will be demonstrated that certain gold(I) complexes show exciting cytotoxicity profiles, rivalling those of cisplatin and standard chemotherapeutic agents. More importantly, anti-tumour activity is demonstrated in vivo, albeit in a mouse model. The presentation will give a brief overview of ?metals in medicine? with a focus on gold and will summarise some recent advances in the development of goldbased anti-tumour agents.

Oct 1, 2003