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By M. A. Halim, V. I. Lakshmanan, Z. Jankovic

An innovative mixed-chloride process for the separation of iron from lateritic ore is described. The separation of Fe(III) from leach liquor is an important process step for the recovery of nickel and cobalt. The patented process of Process Research ORTECH Inc. uses a lixiviant containing hydrochloric acid (HCl) and magnesium chloride (MgCl2) for the leaching of lateritic ores/concentrates followed by the selective solvent extraction step of Fe(III) over other value metals such as Ni and Co. The use of MgCl2 increases the activity of the hydrogen ion in the lixiviant, which reduces the consumption of HCl in the leaching stage and enhances the formation of HFeCl4-, thereby increasing the solvent extraction efficiency of Fe(III) with ketone. The process produces high purity iron oxide (Fe2O3) and regenerates HCl by the pyrohydrolysis of the FeCl3 rich pregnant strip solution. The developed process flowsheet is in closed loop, economically attractive and environmentally friendly.

Jan 1, 2015

By J. A. Brusset

THE Greenhill mine of West Canadian Collieries, Limited, is situated at Blairmore, Alberta, and produces 2,500 tons per day of bituminous coal. On Monday, October 25th, 1943, smoke was discovered by a party of firebosses on their regular weekly inspection of air-ways. Probably the fire had been smouldering for several days but, as it had started on the outcrop at the top of an old raise filled with dirt, only a small quantity of smoke could filter through, and the plume of mist that crowns the fan at that season had prevented the fan-man from noticing it. This raise is only about 200 feet from the fan, and is 70 feet long between the fan-drift and the outcrop. It was impossible to prove the origin of the fire, as it had probably started several days before it was discovered, but it is possible that a careless smoker may have thrown a match into the opening at the outcrop, and that the old, dry timber had caught fire. The airways are in No. 2 seam, a bituminous seam 18 to 25 feet thick surmounted by shales and sandstones. Only 45 feet vertically above it is No. 1 seam, 12 feet thick, overlain by a strong conglomerate. In that vicinity, No. 1 seam had been worked out about ten years ago and the strata between the two seams are undoubtedly fissured. The pitch of both seams is 43 degrees.

Jan 1, 1945

By A. S. H. Kabir, I-H. Jung, J. Su, Yue. S., M. Sanjari

One of the major problems associated with conventional wrought magnesium alloys is the unwanted basal texture that forms during plastic deformation which generally does not change markedly after post-deformation annealing. Formation of precipitates on the recrystallized grain boundaries during annealing may affect the usual rotation of grains towards preferred basal direction resulting in texture weakening. In this study, Mg-Al-Sn alloy was hot compressed at 250°C and annealed at 350°C for various times. The initial as-deformed microstructure was partially dynamic recrystallized with dynamic precipitates on the grain boundaries. After annealing at 350°C, static recrystallization of the bimodal microstructure took place where at this temperature no static precipitates formed. The goal of this work was to study the effect of dynamic precipitation on the texture evolution during the annealing process. Texture evolution was studied during annealing by electron backscattered diffraction (EBSD) technique through a microstructure tracking process. It was found that precipitates on the recrystallized grain boundaries have significant effect on the usual rotation of the grains towards the basal direction, meaning significant texture weakening, which is beneficial for final mechanical properties.

Jan 1, 2015

By G. M. Ritcey, S. H. Lucas

"On the north shore of the St. Lawrence River, in Quebec, are located orebodies of low-grade titaniferous magnetite. The Quebec Mining Exploration Company (SOQUEM), who have an interest in the deposits, believed that beneficiation of the could generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility. A joint research project of SOQUEM and CANMET investigated alkaline roasting of a magnetic concentrate, followed by leaching of the calcine and separation and recovery of Cr and V by solvent extraction. Aluminum was recovered by precipitation.The present paper describes the roast-leach bench-scale and pilot-plant work leading to the development of the optimum conditions f or the integrated process.A plant flowsheet was developed for the treatment of 5 x 106 tons of magnetic concentrate per annum. Estimates of capital and operating costs were made.Based on a recovery of approximately 90% V, 85% Cr and 75% AI, the total hydrometallurgical plant fixed capital costs, including mining, concentration and shipping, are estimated at $1.021 x 109; the operating costs are estimated at $131.92/ton concentrate. Annual revenue from the Na2CrO4.H2O, V2O5 and A12O3 produced is calculated to be $421 x 106.IntroductionThe Quebec Mining Exploration Company (SOQUEM) acquired in 1968 an interest in four titaniferous magnetite orebodies located in Eastern Quebec. 85 miles north of Mingan on the north shore of the St. Lawrence River. The Mingan deposit, with an estimated tonnage of one billion tons, has a reported average grade of 43% Fe, 6.3% Ti , 1.60% Cr, 0.19% V and 6.1% Al with minor amounts of nickel. SOQUEM, on the basis of previous bench-scale data, believed that the recovery of chromium, vanadium and alumina by alkaline roasting would generate sufficient revenue to defray the mining costs and the costs of transporting the ore to a steel production facility on the coast. One of the approaches selected by SOQUEM for beneficiation of the ore consisted of a combination of magnetic concentration followed by alkaline roasting of the calcine."

Jan 1, 1980

By A. G. Pentland

PROSPECTING is popularly supposed to be surrounded with an air of romance and adventure. The word 'prospecting' brings to mind high mountains, northern lakes, and aeroplanes. A note of urgency has been added to this by the war, particularly in the case of strategic, minerals. Prospecting for strategic minerals in a modern mine in full production, although it may Jack the romance of travel in little-known places, has the advantage of having all the necessary machinery at hand and ready to go into action at a moment's notice. HISTORY Tin was discovered in the Sullivan ore in 1925, when a white streak was noticed on a pilot table which was being used to check the amount of galena in the tailing. The mineral which made up this streak was identified as cassiterite. The amount of tin in the ore is so small that, while of scientific interest, it was considered to be of very little economic importance. Nevertheless, several attempts were made to learn something of the occurrence during times when other work was nor pressing. These studies were dropped when anything came up that seemed more important.

Jan 1, 1943

By J. L. Jambor, E. J. Reardon, E. C. Appleyard, J. A. Cherry

Since the 1957 initiation of deposition of mill tailings at the Heath Steele mine, New Brunswick, periodic detailed studies of the tailings geochemistry and mineralogy have been conducted, thereby providing a unique opportunity to examine the geochemical evolution of a sulfide rich mine>tailings impoundment. When deposited, the tailings contained about 85 wt% sulfide minerals, 1 wt% to 3 wt% carbonate minerals, and 12 wt% to 14 wt% alumino silicate minerals. Mineralogical examination of samples of the tailings from deep in the impoundment indicates that little oxidation occurred prior to tailings deposition. The mill process-water deposited with the tailings was neutral to slightly basic and contained low concentrations of Cu, Pb, Zn and As. Sampling of the tailings five years after deposition indicated that sulfide-oxidation reactions, occurring near the tailings surface, had decreased the tailings-water pH and increased the concentrations of Fe, S042-, Cu, Zn and Pb (up to 10 000 mglL, 25 000 mg/L, 2.5 mg/L, 200 mg/L, and 4.5 mg/L, respectively). In 1975, ten years after decommissioning, the tailings could be divided into three zones: an upper oxidation zone in which sulfide oxidation is actively occurring, a hardpan layer, 15 cm to 20 cm thick, composed of tailings cemented by secondary Fe minerals, and an underlying reduction zone in which the tailings are relatively tin oxidized (Boorman and Watson, 1976). Chemical analyses indicated the presence of low-pH waters containing very high concentrations of SOi-, Fe, and other metals (up to 63 600 mg/L SO42-, 28 600 mg/L Fe, 10 mg/L Pb, 600 mg/L Cu and 4000 mg/L Zn), suggesting that there was a period of intense sulfide oxidation between five and ten years after tailings deposition. More recent sampling, conducted some 20 years after the end of tailings deposition, indicates that relatively little change has occurred in the last ten years, thereby suggesting that the hardpan layer has provided an impediment to the downward movement of dissolved constituents. Analyses of the tailings solids show increased accumulations of many metals at or near the depth of the hardpan layer. Evaluations of the long-term evolution of the tailings can be enhanced by comparison of descriptions of the tailings with descriptions of the gossan that overlay the massivesulfide orebody prior to mining. At Heath Steele, this comparison suggests that many of the mechanisms controlling the distribution of metals in the tailings will probably persist over geologic time.

Jan 1, 1992

By Mary Kama, Kaul Gena

"Magnetic skarn ore (MSO) is one of the major copper bearing ore extracted by the Ok Tedi Copper Mine in Papua New Guinea. Copper minerals are recovered by flotation while the iron not associated with copper are discarded as tailings. The objective of this investigation was to determine the iron ore reduction kinetics for the Ok Tedi MSO and ascertain if it can be processed to produce sponge iron for a mini steel plant in Papua New Guinea.SEM-EDAX analyses of the Ok Tedi MSO indicated 10.1% C, 30% O, 0.6% Mg, 1.1% Si, 21.1% S, 0.8% Ca and 36.2% Fe. Most of the iron is in sulfide form. Both naturally occurring and roasted sinters of Ok Tedi MSO samples of different particle sizes were reduced by charcoal carbon at three different temperatures and seven different reduction times. Analyses of the reduced products indicated a metallic iron content of more than 65 wt.% on average.Results showed that there was no significant difference in reduction between fluxed and control materials. Only a slight increase in kinetics with reduced particle size, hence the reaction rate constant (K) did not vary much within the temperatures investigated. Reaction kinetics increases with increasing reduction time at 900°C. Therefore, more iron reduction is observed with particles of 106 µm size. In addition, the results also confirmed that the reduction energy used was higher at 800°C and lower at 1,000°C. In summary, iron reduction can be improved but close monitoring of temperature and reduction times are essential to determine the reaction kinetics of the Ok Tedi MSO. INTRODUCTIONMost mines in Papua New Guinea mine large quantities of iron in the form of sulfides, carbonates, oxides and sulfates that are eventually disposed off as tailings. The Ok Tedi magnetic skarn ore (MSO) contains a significant amount of hematite, magnetite, siderite, ilmenite and pyrite that can be a source of iron. The mineralogical compositions of Ok Tedi MSO reveals more iron minerals than copper, yet all iron containing minerals are collected in the tails from the main copper production stream. Therefore, this study is conducted to investigate the possibility of producing direct reduced iron (DRI), or sponge iron, from the MSO. Such sponge iron may serve as the feedstock for electric arc/induction furnace based mini steel plants in Papua New Guinea."

Jan 1, 2016

By Fazel G. Jahromi, Ahmad Ghahreman

"Atmospheric leaching of arsenical sulfide concentrates, and especially enargite leaching, is one of the major challenges within the current hydrometallurgy research area. One of the recent processes developed for sulfide ore treatment is atmospheric leaching in the presence of AF 5, a novel carbon based catalyst, in chloride media. The quantification of different ion concentrations during enargite and chalcopyrite leaching in the presence of AF 5 were measured and the copper recovery rates of 97% and 96% were achieved. The objective of this study is to shed light on the leaching mechanism of the sulfide minerals. Based on the speciation of iron and copper by different titration methods, the AF 5 catalyst first reduced ferric and cupric ions and then oxidized ferrous, cuprous and arsenite ions. The oxidation behavior of the catalyst enhanced the leaching results. The AF 5 catalyst also caused in situ precipitation of scorodite in leaching experiment. The speciation of ions in the chloride media were simulated by Phreeqc software and the dominant species in the leaching solution were determined.INTRODUCTION The hydrometallurgy of copper has been used for several decades and is still under development for more complex copper sulfide minerals due to their refractory nature. Most of the world copper reserves are in the form of chalcopyrite; and enargite is known as a major contaminant. Pyrometallurgical processing of enargite is problematic due to arsenic release and tight environmental regulations (Peacey, Gupta, and Ford n.d.). On the other hand, lower recoveries in the hydrometallurgical processes make most of these processes impractical. Several leaching processes have been developed for the leaching of copper sulfide minerals. Some of the common treatment methods for copper sulfide minerals are pressure oxidation leaching (POX), CESL, Activox, Albion process, atmospheric ferric sulfate leaching, Dynatec, Galvanox, and Hydro copper process (Barr, Defreyne, and Mayhew 2005; Conner and Anderson 2013; D.G. Dixon, Mayne, and Baxter 2008; Hyvärinen and Hämäläinen 2005; Palmer and Johnson 2005; Rohner, Bartsch, and Ngoviky 2012). Generally it is not viable to dissolve copper sulfide minerals at ambient pressure in mild acidic media and dissolution of these refractory minerals requires harsh conditions in the presence of oxidant materials (Biswas and Davenport 2002). Ferric ions have been used as an oxidant in different media in copper sulfide leaching processes. U. S. Bureau of Mines’ Reno Metallurgy Research Center in 1969 (Haver and Wong 1971) investigated ferric chloride leaching of chalcopyrite. Dutrizac and Macdonald (1972) studied ferric sulfate leaching of enargite. Based on this study, 50% of the copper was recovered at 80-85 ºC after 7 days of leaching. Cupric ions can also be used as an oxidant. Parker, Paul, and Power (1981) stated that cupric/cuprous couples are more effective than ferric/ferrous couples in chloride media because they are rapid and reversible. The Hydro Copper process leaches copper sulfide minerals in chloride solution catalyzed by cupric ions. In this process, copper dissolves as cuprous ions in presence of cupric ions (about 10 g/L) (Hyvärinen and Hämäläinen 2005)."

Jan 1, 2017

"Cobalt refining at Vale Canada (previously known as Inco) has been associated with Ni production. Because certain compounds of both metals carry risks for adverse health endpoints by inhalation exposure, it is critical to understand the aerosol concentrations of specific substances and the metallurgical processes through which they enter the air. Vale Canada has therefore decided to describe the histories of its Ni-related operations and to report industrial hygiene measurements when available. This paper describes electrolytic Co operations carried out at Port Colborne, Ontario (1954–1966), and provides aerosol measurements (1995–2008) for current Co electrowinning operations.RÉSUMÉ L’affinage du cobalt chez Vale Canada (anciennement Inco) a été associé à la production de nickel. Puisque certains composés de ces deux métaux comportent des risques d’effets néfastes pour la santé par exposition à l’inhalation, il est essentiel de comprendre les concentrations en aérosol des substances spécifiques ainsi que les procédés métallurgiques par lesquels ils entrent dans l’air. Vale Canada a donc décidé de décrire les historiques de ses opérations liées au nickel et de divulguer les mesures d’hygiène industrielle lorsqu’elles sont disponibles. Le présent article décrit les opérations électrolytiques effectuées sur le Co à Port Colborne, Ontario (1954–1966), et fournit des mesures de la teneur en aérosol (1995–2008) pour l’extraction électrolytique actuelle du Co."

Jan 1, 2015

By Nigel Saunders, Zhanli Guo

"Quench sensitivity of heat-treatable aluminium alloys is closely related to the precipitation process taking place during quenching. Faster cooling results in less precipitation of coarse phases during cooling, leaving more solutes in the solution before ageing. An alloy in such state would be of greater hardening potential as larger amounts of hardening phases may precipitate out during ageing. Hence, to understand the quench sensitivity of an alloy, it is essential to understand its precipitation process. Precipitation is a diffusion-controlled process and the diffusion is made complicated by the so-called quenched-in vacancies. These vacancies form during solution treatment, become “excess” when temperature goes down, and annihilate during the following cooling and ageing treatments, making diffusion now a function of both temperature and time. This paper first investigates the formation and annihilation of quenched-in vacancies and their effect on diffusion. The diffusion affected by quenched-in vacancies is considered in the kinetic models to realise the calculation of TTT/CCT diagrams for aluminium alloys. The calculated CCT diagrams have been used to explain the observed quench sensitivity and age hardening behaviour of various commercial alloys. The transformation from GP zones to other hardening phases during ageing is also discussed.INTRODUCTION The heat treatment of aluminium alloys mainly consists of three stages: a solution treatment at an elevated temperature, quenching from this solution treatment temperature to room temperature, followed by an ageing treatment to allow the precipitation of strengthening phases(Davis, 1993).The following statements generally describes how quench sensitivity is observed in heat-treatable Al-alloys: faster cooling results in,(i) less precipitation of coarse phases formed at high temperature during cooling, (ii) more solutes kept in solution before ageing, and (iii) larger amounts of hardening phases being formed, i.e. a greater hardening potential. Thus, the quench sensitivity of an alloy is closely related to its precipitation kinetics."

Jan 1, 2018

By A. M. Reyes

Flow field hydrodynamics of serpentine flow channels was investigated numerically using computational fluid dynamics (CFD). The velocity profile simulated by the CFD model was evaluated with respect to experimental results from the literature. Rectangular and tapered flow channels were compared with respect to mixing and water management capabilities, and pressure drop. The CFD model was further developed to account for electrochemical reaction on the cathode side to determine which channel configuration was most effective in reactant conversion. The velocity profile differences between the channels were found to impact reactant conversion, as the rectangular channel had the highest conversion. With respect to water management, although the tapered channel was found to have a higher overall pressure drop, the rectangular channel was found to have higher shear and pressure forces acting on simulated liquid water droplets in the channel.

Jan 1, 2005

By O. A. Ojo, N. Esmaeili

"The effects of brazing and use of composite powder mixture as interlayer material on hot corrosion resistance of brazed IN738 superalloy were studied. Brazing was observed to result in significant reduction in the hot corrosion resistance of the superalloy. However, application of composite powder mixture, which consists of additive superalloy powder, enhanced the hot corrosion resistance of brazed samples. It is also found that although the use of composite powder mixture increased hot corrosion resistance of brazed alloy, if the additive powder completely melts, which is possible during brazing, it can significantly reduce the hot corrosion resistance of the brazed joint. Elemental micro-segregation during solidification of the joint with completely melted powder mixture produces chromium depleted zones and consequently reduces hot corrosion resistance, since a uniform distribution and adequate chromium concentration is necessary to combat hot corrosion. This has not been previously reported in the literature and it is crucial to the use of composite powder mixture for enhancing the properties of brazed superalloys.INTRODUCTION Superalloys have been developed in response to the increasing demand for materials with higher resistance to corrosion and creep and also with higher mechanical strength at higher temperatures (Smith, 1981). Ni-base superalloys are predominantly used in manufacturing hot sections of gas turbine engine components. This is due to their high strength and corrosion resistance in extremely high temperature service environments which is typical for hot sections of gas turbine engines (Miglietti, 2009). The continuous demand for higher efficiency and output has resulted in the use of higher operating temperatures and gas pressure in modern gas turbine engines (Jahnke & Demny, 1983). Consequently, this has caused thermal and mechanical stresses which result in severe degradation and damage of gas turbine engine components due to creep, fatigue and hot corrosion (Zhang, Feng, & He, 2006). The decision to replace or repair damaged parts depends on the overall repair cost and expected life of the repaired components (Jahnke & Demny, 1983). However, in most cases, it is more cost effective to repair damaged parts rather than use a full replacement."

Jan 1, 2017

By A Smirnov

The problem of thin and very thin coal seam extraction is examined in a long perspective of Ukraine?s fuel and energy industry development. The technical and economic benefits of the coal seam selective mining technique are described, including beneficial environmental impact.

Aug 1, 2013

By R. D. Brown

"AbstractOver the past five years, tax rates in the Canadian mining industry have skyrocketed upward across Canada, as both federal and provincial governments have sought to increase their share of mining revenues.However, the past few years have not only brought high tax rates to the industry, but also a number of important new federal and provincial tax incentives.In large part, these incentives ~ special credits or reduction in tax for carrying out specific exploration, processing or other activities - have helped to moderate the adverse effects of the higher tax rates and have provided inducements for exploration and processing activities which might not otherwise have been undertaken.However, the effectiveness of certain of these incentives can be questioned: our over-all tax structure now consists in large part of punitively high marginal rates with some extraordinarily generous but capricious tax reductions for specific activities and may not be in the best long-term interest of either the industry or the nation.A rational tax structure, with moderate and stable tax rates, together with reasonable incentives confined to activities specifically requiring them, could be a more effective spur to investment than the present tax and incentive jungleIntroductionIN THE YEARS since federal tax reform, the mining industry in Canada has faced a continued escalation in its tax burdens as federal and provincial governments have leapfrogged each other in imposing new and higher taxes on the industry. The result has been that marginal tax rates imposed on mining and processing activities throughout Canada have jumped to hitherto unparalleled levels."

Jan 1, 1977

By P. J. Finnis

This paper describes the use of wire rope on open-pit mining equipment, giving specifications and examples of the performance achieved. Installation methods are also discussed, making the paper of considerable practical use to mine operators.

Jan 1, 1973

By W. L. Strand, D. N. Madge

"Experimental and pilot operations in bituminous sand processing require due care and attention in the design and analysis of measurement programs. This paper deals with a case study in experimental design and data analysis for a series of experimental campaigns that have been conducted over the past five years by Kilborn Western Inc., acting on behalf of Bitmin Resources. Beginning with the design of the experiment and following into the use of linear and nonlinear regression models, the phenomenology of bitumen extraction is illustrated. The final testing program tested 13 oil sand types as well as a wide range of process variables for all the unit operations of the complete process.The program was successful in developing process fundamentals and scale-up criteria. Several phenomenological models were proposed and tested. Their range of applicability was explored. This paper illustrates the range of applicability of these models and discusses the development of alternative models.IntroductionOver the past five years Kilborn has conducted a series of bench scale and pilot scale experiments designed to explore the phenomenolgy of a new concept in medium temperature processing of bituminous ores. These experiments at feed rates ranging from .1 to 24 t/h were conducted on water wet sands from the .Athabasca region near Fort McMurray. They were based on experimental designs chosen to provide a systematic means of identifying the response surfaces of the process over a range of conceptual designs. The following diagram shows the experimental arrangement:"

Jan 1, 1998

By Olaf Kessler, Jan Kalich, Michael Reich, Julia Osten, Uwe Füssel

Modern automobile bodies consist of different materials, e.g. aluminium alloys and high strength steels. Mechanical joining, e.g. clinching, is very suitable for joining aluminium and steel sheet. But clinching needs a sufficient ductility, which is no longer supplied by high strength steels. Laser-assisted clinching has been shown, to be able to join aluminium and high strength steel sheet successfully. Thereby the steel sheets were heated locally for short times to increase their ductility. Due to the thermal contact between steel and aluminium sheet the aluminium alloys also achieve a local short-time heat treatment. This fact may cause a significant impact, as aluminium sheet in automobile bodies is often used in T4 (or similar) condition and later artificially aged during the paint bake cycle. Aluminium alloys 6016 and 6181 have been short-time heat treated with heating rates up to some 100 K/s. Precipitation and dissolution processes have been monitored in-situ by calorimetry. Mechanical properties have been investigated on as well as after short-time heat treatment by deformation dilatometry. The results show, that suitable short-time annealing parameters during laser-assisted clinching can increase ductility and at the same time act as retrogression for aluminium sheets, resulting in increased strength after aging.

Jan 1, 2015

By M. Cousineau, S. Gariepy

"Current business and corporate environments push for improving metal accounting practices in smelters. The ensuing projects commonly proceed along a bottom-up approach. As such, efforts are first put on reviewing the measurement system and then on remedying the identified weaknesses. The focus is thus moved to mass/metal balance only after the measurements upgrade process has been completed. However, practice has shown that assessing the high variances related to suboptimal measurement processes is complicated without the help of statistical data reconciliation. This bottom-up approach leads to a to-do list that can not only exceed available resources but also lack prioritization in view of achieving the targeted end use. This paper describes an upgrade project done differently where all the three dimensions of the metal accounting system: hardware, software, and people were instead involved at the onset. Personnel was thus trained on data reconciliation software at the beginning of the project to make the reconciled mass balance benefits available earlier in the upgrading project. This has pinpointed the most critical measurements where accuracy and reproducibility should be improved. Overall, not only the instrumentation retrofitting process has been streamlined, but the global risk for the whole upgrading project has been significantly lowered.INTRODUCTION Mining companies are pressured to improve their production accounting practices in response to the strengthening of corporate requirements for timely and accurate production reporting (Gaylard, Randolph, & Wortley, 2014). Smelters are not spared from these changes. However, their unique situation in the mining value chain set them as strategic targets for upgrading projects. They usually have a longer lifespan than concentrators thereby offering an extended lifecycle to justify investments. Furthermore, numerous smelters have toll agreements with third parties. Accurate cost and production accounting is, therefore, a vital piece of information to fix acceptable contract conditions. Mining companies are ultimately aiming at a clearer view of the operating performance of each business unit to improve their business decisions in a competitive environment. This sought for increase in visibility through plant performance can only be achieved through an upgrade of the metal accounting system. Figure 1 shows the different components of a state of the art system (Gaylard, Morrison, Randolph, Wortley, & Beck, 2009)."

Jan 1, 2017

By Michel Ruel, Ali Soltanzadeh, Benjamin Légaré

High fidelity commercial process simulation packages can be used at different stages of a greenfield project, from initial plant design to operator training in the later stages. However, there are several factors that make the software less attractive for small and medium size brownfield projects, such as the licensing cost and the fact-finding manpower required for model design and simulator maintenance. In this paper a different approach is described. The knowledge gathered from operating personnel was used to implement higher level models based on plant data, operating heuristics, and experience rather than detailed component-level models. The computing platform used was a low-cost, well-established, control system vendor-independent software. Throughout this paper we demonstrate the success of implementing this model-based approach using two industrial examples. The first example is a simulation of the carbon monoxide (CO) distribution system at a metallurgical complex. The purpose of this simulator was to test new control strategies and PLC programs prior to implementation. CO being a toxic combustible gas, validation of the suggested control system changes was necessary for plant safety. Simulation of specific operating conditions helped alleviate concerns and improved plant-wide acceptability of the new operating philosophy. The second example is a boiler simulator at a petrochemical plant. The operator training simulator (OTS) was designed as a platform for experienced operators to practice handling rare or abnormal conditions. A customized medium-fidelity model was developed for this targeted application where the cost of a full scale high-fidelity model could not be justified.

Jan 1, 2016

By P. Klossek

It is estimated that China accounts for 94% of the world supply of rare earths (Roskill, 2011). This fact, together with the impact of China?s export policy, poses a substantial risk to the security of the rare earth supply as well as a rare earth price risk. This situation has motivated an increase in the number of rare earth projects under development, i.e., there are currently more than 440 worldwide (Technology Metals Research, 2012). However, economically and environmentally acceptable processing technology to produce tradable products from rare earths (e.g., separated rare earth oxides) is not freely available on the market at the moment. In this respect, a lot of research and development has been initiated on this topic, in academia as well as in industry. Using a proprietary model and scenario-based analysis, we studied the impact that the development of rare earth processing technologies would have on the rare earth market and the economic feasibility of rare earth projects mentioned before. The analysis showed that this impact varies depending on the technology type (e.g., technology can affect project production volume, cost structure or both) and the legal context of the invention (e.g., free or limited by patenting availability of a new technology). The effect of a technology which influences project production volume is not the same as of a technology which changes project cost structure. The impact of a patented processing technology differs from the impact of a processing technology which is freely available on the market. In the case of a new technology which is limited by patenting, its impact depends on the market position (?producing?, ?next-coming?, or ?not producing? project) of the patent holder. The paper contributes to existing research by studying the dependence of the expected micro- and macroeconomic impact of rare earth processing technology developments on the properties of a new technology (e.g., costs, legal framework etc.). By this means, the paper adds to existing knowledge and attempts to make the rare earths market more transparent and predictable from a perspective outside China.

Aug 1, 2013