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By Z. Z. Öztürk, N. Sarica, A. H. Üçisik, C. Bindal

"Titanium oxide films were fabricated on commercially pure titanium surfaces via anodization procedure. Anodization parameters, anodization time and voltage were altered, whereas temperature and chemical composition of anodization bath were kept constant. The main idea in this study is to obtain rough titanium-oxide surfaces. The type and feature of titanium oxide formed were observed via SEM and EDX analyses. What was revealed from SEM and EDX analyses were combined with Ti-O phase diagram in order to make judgment on the type of phases obtained, e.g. solid solution and/or compounds. Studies on the different regions of each sample showed that surfaces consist of different titanium oxide compounds with various O/Ti ratios in nano level and solid solutions varying in terms of chemistry on the same sample. Thus together rough surfaces and inhomogeneous distribution of "titanium oxides" were obtained. It was also found that when anodization time and voltage were increased, more granular surface with higher O/Ti atomic ratio was obtained."

Jan 1, 2015

By Ferri Hassani

Some future challenges ? People ? Shortages of HQP (e.g. engineers, scientists, geologists) ? Environment ? Regulatory standards - GHGs and air pollutants ? Mine waste management and rehabilitation ? Downstream processing (e.g., alternatives to cyanide) ? Climate change adaptation ? Lowering costs and improving productivity ? Energy efficiency ? Mine automation ? Health and safety ? Deep mining

May 1, 2008

By Marc Arpin

La Bolivie possède tout pour réussir. Son vaste territoire de plus d'un million de km2 et qui occupe une position stratégique au coeur du continent sud-américain recèle des ressources naturelles (forêts, minéraux, gaz naturel, etc) variées et abondantes. Elle a une frontière avec pas moins de 5 pays dont le géant que constitue le Brésil ainsi qu'avec l'Argentine, l'autre puissance régionale. Pourtant, malgré tous ces atouts, la Bolivie demeure l'un des pays les plus pauvres du continent. Ce paradoxe n'est nulle part mieux reflété que dans le secteur minier. Celui-ci fait face à une situation de crise en dépit d'une tradition minière de plus de quatre siècles et d'un potentiel géologique indiscutable ayant conduit à la découverte et à l'exploitation de fabuleux gisements d'argent et d'étain. Les habitants des districts miniers vivent dans des conditions de pauvreté extrême et les indicateurs de développement humain de ces régions sont parmi les plus bas en Amérique du Sud. La Bolivie réussit difficilement à attirer les compagnies minières alors que, chez les voisins, et particulièrement en Argentine, qui n'a pas de tradition minière, les investissements miniers majeurs affluent. Dans cette conférence, nous chercherons à expliquer les causes de cette situation et proposerons des solutions possibles.

May 1, 2001

By A. Idegami, M. Imamura, S. Heguri, Y. Ozaki

"Nickel powder can be produced by the reduction of a nickel ammine complex solution by hydrogen at high temperature and pressure. To minimize the deposition of fine nickel on the surface of the reactor and other equipment, seed crystals are added to the initial solution to promote nucleation of the nickel powder. Such seed crystals catalyze the precipitation of the nickel particles on the surface of the seed and enhance grain growth. In this study, nickel nuclei were precipitated by the addition of a polymer to the nickel ammine complex solution, resulting in the production of nickel powder. Thus, we herein propose a model that explains the effect of the polymer in the precipitation of nickel nuclei.INTRODUCTIONNickel powder is commonly produced via a hydrometallurgical process from the hydrogen reduction of a solution containing a nickel ammine complex at high temperatures and pressures, and this process was commercialized in the 1950s by Sherritt Gordon (Sherritt International, Canada, Benson & Colvin,1973; The Staff, Research and Development Division, Sherritt Gordon Mines, Ltd., 1958).In the above transformation, upon the injection of hydrogen gas into the solution, nickel is reduced as outlined in Equation(1), ultimately resulting in the production of nickel powder.Ni(NH3)nSO4+ H2?Ni+ (NH4)2SO4+ (n-2)NH3(n:2–6)(1)In this process, seed crystals are added to the reactor to suppress the precipitation of fine nickel (scaling) and to enhance nickel reduction (Benson & Colvin, 1973; Mackiw, Lin & Kunda, 1957). More specifically, iron sulfate and a small amount of dispersant polymer are added, which leads to the formation of nuclei. Upon subsequent hydrogen reduction, the reduced nickel can then be deposited on the nuclei, allowing nickel particle growth to take place. However, this results in iron contamination in the final nickel product, and so the use of pure nickel as a seed crystal is desirable to produce high quality nickel powders."

Jan 1, 2017

By Stéphane Robert

This document presents estimates of future "total cash cost per ounce" and "minesite cost per tonne" that are not recognized measures under United States generally accepted accounting principles ("US GAAP"). This data may not be comparable to data presented by other gold producers. These future estimates are based upon the total cash costs per ounce and minesite costs per tonne that the Company expects to incur to mine gold at the applicable projects and do not include production costs attributable to accretion expense and other asset retirement costs, which will vary over time as each project is developed and mined. It is therefore not practicable to reconcile these forward-looking non-GAAP financial measures to the most comparable GAAP measure. A reconciliation of the Company's total cash cost per ounce and minesite cost per tonne to the most comparable financial measures calculated and presented in accordance with US GAAP for the Company's historical results of operations is set forth in the notes to the financial statements included in the Company's Annual Information Form and Annual Report on Form 20-F, for the year ended December 31, 2009, as well as the Company's other filings with the Canadian Securities Administrators and the SEC.

May 1, 2011

By Olanrewaju A. Ojo, Xu Wang, Jian Xin Dong, Lina Zhang, Jerzy A. Szpunar

"The influence of crystallographic orientation on the pitting corrosion behavior of Ni-Fe-Cr alloy 028 was studied by a combination of X-ray diffraction (XRD), electron backscatter diffraction (EBSD), potentiodynamic polarization technique and atomic force microscopy (AFM). The results show that there is anisotropy of pitting corrosion that strongly depends on crystallographic orientation of surface planes. The distribution of pits frequency in standard stereographic triangle shows that the crystallographic planes close to {100} are more prone to pitting corrosion compared to planes of {110} and {111}. The calculation of surface energy (001) and (111) shows that the planes of high packing density of atoms have low surface energy with concomitant strong resistance to pitting corrosion. A correlation function between crystallographic orientation and pitting corrosion susceptibility suggests a method not only to predict the pitting resistance of a known textured materials, but also to improve corrosion resistance by controlling materials texture.INTRODUCTIONNickel-iron-chromium(Ni-Fe-Cr) alloys are widely used in various industries and engineering sectors due to their combination of good mechanical properties and high corrosion resistance(Hibner, 2001; Thomas, 2006; Ghosh, 2005).Ni-Fe-Cr alloy 028 (alloy 028)has such important characteristics worth mentioning. Alloy 028 contains high amounts of nickel, copper and molybdenum which improve its resistant to corrosion attack in reducing medium, and presence of high level of chromium makes it more resistant to oxidizing species. Moreover, alloy 028 is less expensive because of higher amount of iron compared to other similar alloys. Currently, alloy 028 is manufactured as evaporator tubes applied in the phosphoric acid production; production tubing and casing used in deep and sour gas wells; heat exchangers employed in nuclear power plants, and seawater-carrying piping and seawater-cooled heat exchangers (Bankiewicz, 2012; Kivisäkk, 2003; Gómez, 2003; Xian, 2012; Bellezze, 2004)"

Jan 1, 2017

The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.

Jan 1, 1963

By C. Pichler, C. Benigni, J. Antrekowitsch

"The recycling of steel mill dust results in zinc oxides which are sold to the primary industry in or-der to recover zinc in its metallic form. Due to the contained impurities - chlorine and fluorine - these sec-ondary oxides are usually charged into the roaster together with primary concentrates. Appearing problems in this furnace limit the application of secondary materials. Based on the zinc amount, a direct leaching, assumed that a low halide concentration is present, would be possible. To use the zinc solution directly in the electrowinning stage, the concentration of impurities, first of all iron, is limited. Iron can be found in secondary zinc oxides due to carry over during the recycling process. In order to reduce the iron content in the solution, the leaching has to be pH-controlled. This leads to a limited number of simple purification steps before the solution enters the electrolysis. Various trials were performed to evaluate the influence of temperature, time and sulphuric acid concentration on the iron dissolution. This paper deals with the results and also focuses on other impurities such as halides. Additionally, the soda washing process, usually done with secondary zinc oxides to remove most of the halides, and the challenges within this step are discussed.INTRODUCTION Recycling of steel mill dust, which is the main zinc containing residue, in the Waelz process dis-plays the common method worldwide. The product of the process is a secondary zinc oxide which is con-taminated with different elements like lead, iron and halides due to mechanical carry over or evaporation. Depending on the feeding material the concentration of each element in the dust is varying. The zinc con-tent of the product, also called Waelz oxide, lies around 65–68%. Based on these values it presents an al-ternative to the primary concentrate for the production of metallic zinc. The contained halides limit the direct utilization in the leaching stage and therefore have to be reduced. State of the art is a soda washing process but also solvent extraction gives a possibility to remove chlorine and fluorine but the desired con-centration for the electrolysis is hardly reachable (Antrekowitsch et al., 2016) Iron is present as an undesirable component of such secondary zinc oxides due to carry over. During the hot acidic leaching of the secondary concentrate, iron is dissolved too. Based on the higher electrical potential iron has to be removed before the zinc solution enters the electrowinning stage. It is usually removed by precipitation as goethite, hematite or jarosite, which is the common precipitation residue (Ismael et al., 2003)."

Jan 1, 2017

By W. L. Bancroft, Peter Price

"What is now known as the 'Waite section' of the property of Waite Amulet Mines, Limited, was originally the Waite-Ackerman-Montgomery mine. It includes a group of twenty-eight claims lying on either side of the Duprat-Dufresnoy township line, and about 8 miles north-northwest of Noranda, Quebec. ,The original discovery of ore on the property was made by Thomas Montgomery in Block Q, Duprat township, and was staked by him on behalf of himself, I. C. Waite, and C. H. Ackerman, in the summer of 1925. The property was optioned late in 1925 to N. A. Timmins who, after trenching and drilling the deposit, sold his 85 per cent interest to Noranda Mines, Limited. Early in 1927, a company known as Waite-Ackerman-Montgomery Mines, Limited, was formed and shaft sinking and development undertaken. Production commenced in August, 1928, ·and continued tJ May, 1930, when, owing to falling metal prices, shipment of direct smelting ore was stopped. Development of the mine by shaft sinking, drifting, and drilling continued until March, 1932, when owing to the prolonged low price of metals, the property was closed down. In September, 1933, an amalgamation with Amulet Mines, Limited, was effected, the new company being called Waite Amulet Mines, Limited. Early in 1937 operations were resumed, first by direct shipments to the smelter and later by aerial tramway to the Amulet mill. Operations have been continuous up to the present time, reaching an average of 720 tons a day milled for the year 1940. Production during the initial period (1928-1930) amounted to 75,811 tons, having an average grade of 7 .11 per cent copper, 4.47 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton. During the second period (1937 to end of 1946) , 1,060,524 tons, having an average grade of 4.53 per cent copper, 2.97 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton, were produced."

Jan 1, 1954

To create a successful growth oriented diamond company that succeeds in the practical business of mining and selling rough diamonds, and which pursues an aggressive exploration strategy to seek and develop worldclass diamond mining opportunities in a market that has become increasingly under-supplied.

May 1, 2008

By T. Purushotham, B. Samanta

ABSTRACT; The shaft bottom junction in a mine ventilation system is an important source of shock loss due to the combined effect of bend and area change. The occurrence of high-volume ?ow rates through this con?guration can potentially result in high energy losses. The current research examines the process of shock loss at a characteristic shaft bottom junction of an underground coal mine. Investigations are per-formed on both laboratory-scale models and three-dimensional computational ?uid dynamics (CFD) simulations, under both exhausting and forcing shaft bottom conditions. The effects of the plat roughness and the shaft bottom length on the shock loss factor values are also examined. The studies show that the combined effect of bend and area changes that occur at the shaft bottom junction results in shock loss factors that are much higher than those values resulting from abrupt area change only. The transition from a smooth wall condition to an unlined rough airway condition (relative roughness, e/d = 0.112) can increase the shock loss factors by 40%. The effect of shaft bottom length on the shock loss factor has not been clearly established due to con?icting results produced by scale model studies and the CFD simulations.

Jan 1, 2010

By Masahiro Eguchi, Giuseppe Granata, Chiharu Tokoro, Hiroki Fukuda, Yuichiro Toba, Shungo Hobo

"Currently, large amounts of wastewater containing boron are discharged from industries like coal-fired power plants. Although coagulation-sedimentation is widely employed for their treatment, only a little consideration has been given to its mechanism. An additional problem is that the produced sludge has poor solid-liquid separation. This study is focusing on coagulation-sedimentation using magnesium, examining the mechanism and improving the solid-liquid separation. First, the co-precipitation with magnesium hydroxide was conducted against high-concentration boron wastewater with 500 mg/dm3as B. Second, in order to improve the solid-liquid separation by maintaining high reactivity, low-crystalline magnesium oxide was synthesized from magnesium carbonate by calcination at 400–700°C. It was tested as an adsorbent of boron and compared to co-precipitation with magnesium hydroxide. Co-precipitation showed high removal capacity. X-ray diffraction (XRD) of the sludge revealed the presence of other compounds besides magnesium hydroxide. This result suggests that other processes play a role other than simple adsorption on to magnesium hydroxide, and provides a plausible explanation for the observed high separability. As for the adsorption, the synthesized magnesium oxide immobilized as much or more amount of boron than co-precipitation. Furthermore, the results of fourier transform infrared spectroscopy (FT-IR) suggested the residual magnesium carbonate improved solid-liquid separability due to its poor solubility.INTRODUCTIONBoron is used in various industrial applications. In glass industry, the addition of a little amount of boron into glass products can enhance heat-resistance and chemical-resistance. Semi-conductor industry also employs boron as dopant for silicon. From these industries, large amounts of wastewater containing boron have been discharged. Additionally, coal-fired power plants have been recently discharging highly concentrated boron wastewater because the amount of boron contained in coal has been increasing due to a gradual decrease of the quality of coal. Since boron is partially proved to be toxic for animals, plants, and human beings (WHO, 1998),the guideline of the World Health Organization limit the boron concentration in drinking water to 2.4 mg/dm3(WHO, 2009).Because boron does not precipitate from solutions by simply changing the pH, the removal could be carried by operations such as adsorption or ion exchange. However, since ion exchange is an expensive operation with relatively low capacity, it is not suitable to treat the large amounts of wastewater produced by heavy industries like the coal-fired power plants. Therefore, coagulation-sedimentation method is still widely used as a suitable alternative way."

Jan 1, 2017

By W. H. MacLean, S. Liaghat

The Key Tuffite is a thick (0.3 m to 6 m) and laterally extensive (-10 km) cherty, sulfide-bearing tuff unit in Archean greenstones in the Matagami mining district in northwestern Quebec. It lies at the contact of the Watson Lake Group and overlying Wabassee Group volcanic rocks, and is host to major Zn-Cu volcanogenic massive sulfide deposits. The tuff component is highly altered and its volcanic precursors are not identifiable by petrographic means. The tuff is mixed with a volcanic exhalative component comprising chert, carbonate and sulfides (pyrite, pyrrhotite, and minor sphalerite and chalcopyrite). The normative mineral composition of the Key Tuffite is 33% quartz, 28% sulfides, 16% sericite, 8070 carbonate, 6% chlorite and 9% other minerals. In the vicinity of the Bell Allard and Orchan mines, the precursor tuff components are identified using immobile major and trace elements, as Watson Lake tholeiitic rhyolite (Zr/Y = 1.5 to 3.5, LaN/ybN = 1.7 to 2.8, SiO2 = 72.5 ± 1.2 wt %, and Wabassee calc-alkaline andesite (Zr/Y = 9, LaN/YbN= 4 to 8, SiO2 = 56% to 65%). Immobile element computation techniques were used to calculate mass additions and losses in the conversion of the tuff to the Key Tuffite. Average net amounts of FeP3 (27% total iron), Si02 (14%), Cao (8%), S and K2 (+ 2%), were added, Nap was removed (-2.8%), and MgO was over-all unchanged. Total net mass change was +63%, which comprises mainly exhalative additions, but also includes changes owing to hydrothermal alteration of the tuff component.

Jan 1, 1992

By D. M. Maijer, S. L. Cockcroft, S. Modak, A. B. Phillion

"A comparison between hydrogen-diffusion-based micro-porosity formation and growth behaviour of two important aluminium foundry alloys, B206 (Al-Cu) and A356 (Al-Si-Mg) is presented in this paper. Specifically, the predicted pore size and pore fraction distribution of these two alloys resulting from directional solidification and identical hydrogen concentration are investigated numerically based on a model proposed by Yao et al. (2011. Met. & Mat. Tran. A. 42A, 4137–4148). This model takes into consideration the initial hydrogen content in the melt, the cooling rate, the partitioning of hydrogen between the solid and liquid phases, and the evolution in solid fraction with temperature. Due to different alloy chemistries, the activity of hydrogen in B206 and A356 are quite different, as are the solidification range and the resulting solidification microstructure. Being a primary alloy, B206 has dendritic microstructure and solidifies over nearly 135°C (505–641°C), whereas A356 contains fifty percent eutectic microstructure, and solidifies over 80°C (533–613°C). This allows a very different behaviour of micropores i.e. the effective pore radius in B206 is quite a bit lower as compared to A356, as is the pore number density. The evolution of local hydrogen concentration in liquid metal is analysed and compared for both the alloys.INTRODUCTION Over the past decades, the demand for materials with enhanced strength-to-weight ratios has significantly increased in the aerospace and automobile industries in order to improved fuel efficiency. For many automotive components, particularly shape castings, the trend is towards replacing ferrous alloys with aluminium alloys. The increase in the use of Al is primarily due to its low density, about one-third that of steel, and its relatively good strength that allows for weight reduction without reducing performance. Presently, Al-Si based alloys (e.g. A356) are the most prevalent due to their good mechanical performance in strength-to-weight ratio and excellent castability (Atwood et.al., 2000). However, superior mechanical properties can be achieved using Al-Cu alloys. For example, the alloy B206 offers a higher strength while retaining excellent ductility (Poirier et.al., 1987)."

Jan 1, 2017

By R. E. Martin

"The Westerose Leduc (D-3) pool, a Devonian reef reservoir situated in Central Alberta, Canada, has now been producing for over seven years. As a unit operation, the pool pro-vides an interesting example of the full exploitation of gravity segregation tendencies. The reef has a 238-foot oil column, underlain •by bottom water and over-lain by a substantial gas cap. The original hydrocarbons in place were 147.96 million STB oil and 94.4 MMMCF of Taw gas cap gas. Nine-teen producing wells on 80-acre spacing have been completed, most of which are highly productive. Gas injection operations return solution gas to the gas cap. A study of the rock and fluid properties of the pool show it to be conducive to production by gravity segregation at high rates. Monthly average producing rates have varied between 800 B/D and 8,000 B/D and have recently totalled 3,000 BID to 5,000 B /D. Recovery and performance predictions under partial pres-sure maintenance at 10,000 BID indicate an ultimate recovery of 66 per cent of the original oil in place. In the absence of pressure maintenance, recovery would be only slightly less."

Jan 1, 1960

By J. A. Brown, F. P. Kerr, M. A. Archer

Extensive testwork on Global Atomic’s Dasa Project in Niger has been conducted at SGS Minerals laboratory in Lakefield, Ontario. Much of this testwork has focused on a two-stage counter-current leach as a means of improving leach efficiency and decreasing reagent consumption. The ore contains uranium mineralization requiring relatively high sulphuric acid concentrations during leaching to achieve acceptably high extractions. Excess free acidity in the leach solution may be utilized by recycling the high acid solution and contacting it with fresh ground ore. The resulting pregnant leach solution (PLS), now higher in uranium concentration and depleted in free acid, is forwarded on to uranium recovery by solvent extraction. The first stage residue proceeds to the second stage leach where fresh acid and oxidant are provided to leach the remaining uranium. This paper presents the results of the testwork conducted on both a Master Composite and Variability samples.

Jan 1, 2020

By C. Samuelsson, H. Ahmed, B Björkman, A. Andersson

The cost of raw material and energy is a continuing driving force towards working with increasing the recycling of ore based steelmaking residues. In Sweden no on-site sinter plants are operated at the integrated steelworks. Instead, selected residues from the plant are incorporated in a cold bonded briquette product which is recycled to the process via the blast furnace (BF). Since the BF sludge is the major bleed of zinc out of the furnace it is required to be de-zinced prior to recycling in the briquette product. In the present work landfilled BF sludge has been characterized with respect to chemical composition, particle size distribution, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The sludge was also subjected to laboratory scale hydrocyclone trials aiming at reducing the zinc content making the sludge viable for recycling. The results suggested that the sludge had been agglomerated prior to the characterization and hydrocyclone treatment. The zinc removal using the hydrocyclone was discussed.

Jan 1, 2015

By O. Lashkari, A. Charette, R. Ghomashchi

Conventional casting at low pouring temperature was employed to produce semisolid metal, SSM, billets of A356 Alloy. The deformation behavior of the as-cast SSM billets was studied using parallel plate compression viscometry. The compression tests were carried out at different applied pressures, and fractions solid. The rheological studies were conducted assuming the SSM slurry behaving like Newtonian and non Newtonian fluids respectively. The calculated viscosity numbers confirmed pseudoplastic behavior of the SSM billets and were correlated to fraction solid and shear rate proposing the following empirical equation which is valid at low shear rates, less than 0.01 s-1, and fraction solid of0.33-0.46: 0 log77 =5.56-l.38fs -(l.56fs +0.14)logy Aluminium 2006 45th Annual Conference of Metallurgists ofCIM Montreal, Quebec, Canada Edited by G. Dufour, F. Paray and J. Tessier 0.33<fs<0.46

Jan 1, 2006

By J. -F. Blais, M. -O. Simonnot, J. Mocellin, G. Mercier, J. -L. Morel

Large quantities of ferromanganese sludge are generated as waste material by blast furnace during the manufacturing of ferromanganese. These slags are very rich in manganese, zinc and lead (5 to 40 %). These residues have been deposited in a pond in periphery of the steel industry. Considering the market value of the metals, these brownfield sites can now be considered as secondary resources. We have developed a hydrometallurgical process for selectively leaching Zn, Mn and Pb in order to produce compounds of Mn and Zn pure enough to be economically recoverable and a residue rich in Pb. Batch laboratory experiments were carried out to determine appropriate leaching conditions to maximize zinc extraction (100 %) and manganese extraction (90.0 %) with sulfuric acid and to generate a residue containing 15 to 30% of lead. This Pb residue is recyclable by another process.

Jan 1, 2015

By Tanai Marin

Modelling of pyrometallurgical processes can become extremely challenging when the process involves complex chemical reactions, phase change, multiphase flows, heat and mass transfer and fluid flow. Traditionally modelling involving complex thermodynamic equilibrium and thermochemistry are treated separately from problems in which transport phenomena are dominant, such as CFD and heat transfer studies. The separation is also necessary due to the lack of modelling tools that can effectively couple both solution thermodynamic and transport phenomena or even multiphysics problems. However, there are, quite often, problems in high temperature process metallurgy in which it is not possible to simplify this two modelling approaches. Typical cases of this are for example, the modelling of slag freezing on furnace walls (electric or flash furnaces) to create a protective layer in front of the refractories hot wall, the formation of build up from the matte or metal phases at the hearth of the furnace, calcine smelting from charging piles into slag phase, etc. The problem is even more challenging in nonferrous pyrometallurgy as most, if not all, of the condense phases are highly non ideal solutions involving several components and exhibiting complex crystallization paths and miscibility gaps, such as the Fe-Ni-Cu-S matte, FeO-Fe2O3-SiO2, FeO-MgO-SiO2 slags, etc. In this paper, an approach to model coupled problems involving multiphysics and solution thermodynamic is presented. The approach consists in developing in-house a library containing the Gibbs energy minimization routines and using the local equilibrium concept for process modelling from a multiphysics commercial software (COMSOL). Simple test cases, such as building a non-ideal binary phase diagram on a CFD package is presented, the limitations and of other classic approaches such as equilibrium or Scheil cooling are discussed and compared to this model.

Jan 1, 2015