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By B. C. Curson

A comprehensive simulation of .the gas handling system in BHP Copper's San Manuel smelter was developed using AFT Fathom software, with the objective of minimizing SO2 emissions while maximizing smelter throughput. Once verified with plant data, the simulation quickly revealed' the complex interactions occurring between individual converters and the flash furnace. The increased understanding provided by the simulation allowed novel, counter-intuitive control strategies to be developed and tested successfully.

Jan 1, 1999

By Alana Pereira Ramos, Walman Benicio de Castro

Amorphization and martensitic transformation (Ms) characteristics of Ti–Ni-Cu alloy ribbons prepared by melt spinning were investigated by means of differential scanning calorimetry and X-ray diffraction. In these experiments particular attention has been paid to change the wheel linear velocity from 21 to 63 m/s. Then the cooling rates of ribbons were controlled. The effect of this cooling rate and alloy composition on martensitic transformation behavior is discussed.

Jan 1, 2015

By Li Cheng

The SKS copper smelting process was jointly developed by Shuikoushan Mining Corp. and ENFI (Beijing Central Engineering and Research Institute for Non-ferrous Metallurgical Industries) in China. It is a new bath copper concentrate smelting process with oxygen enriched air. The pilot plant testwork was completed successfully in 1993. SKS has demonstrated to be an advanced bottom blown smelting process. This technology got the First Class Prize of Scientific and Technological Progress awarded by CNNC (China National Non-ferrous Metal Industry Corp.) in 1994. The SKS process has significant capital and operating cost advantages. Its environmental and industrial safety and hygiene performance represents a substantial improvement when compared to conventional technologies. The technology has generated great interest in the Chinese metallurgical industry. Feasibility studies and basic designs have been carried out to incorporate in retrofit and green field smelter projects in China and abroad. This paper describes the history of the pilot plant operating data (50 tonnes dry feed/day), and discusses the features of the SKS technology, its application and possible future trends.

Jan 1, 1999

By Halvor Dalaker, Pål Tetlie

The decomposition of methane has been studied experimentally in contact with various oxides at elevated temperatures. For each oxide, the temperature at which the cracking starts has been determined. No correlation was found to exist between the temperature for the onset of cracking for a given oxide and the affinity for carbon of the oxide's metallic component. In terms of potential for using methane as a reducing agent, calculations are presented that indicate that the suitability of an oxide for such reduction depends on the desired methane+oxide reaction being more energetically favourable than the methane+methane=ethylene/acetylene reactions.

Jan 1, 2014

By Tiruttani Munikamal, Suresh Sundarraj

"A numerical model of the induction hardening process of steel cranks has been developed and the predicted results of temperature and phase distribution during this solid state phase transformation process are verified with experimental data from the literature. This heat treatment process involves heating the crank to the austenitic temperature range followed by rapid quenching in water to harden the surface of the crank. The model has been developed using ABAQUS, commercial FEA software. The formation of martensite, pearlite, and retained austenite phases are modeled and implemented through a user defined function in ABAQUS. A sensitivity study on the various process parameters affecting the amount of phase distribution has been carried out.IntroductionThe type of surface and sub-surface microstructure as well as the residual stresses that are present in a component after manufacturing, significantly affects it fatigue performance. The wear resistance of the automotive components such as crankshaft, gears, camshaft and bearings depends on the surface hardness. In order to achieve the surface hardness, these steel components are subjected to a type of quench hardening heat treatment process. There are several heat treatment processes available for the industrial application to improve the mechanical properties of the final part. Case hardening using induction heating is one of the widely used industrial techniques for improving the surface microstructure of a steel component. It consists of two stages i.e. induction heating cycle, followed by quenching in a fluid medium (usually water or oil)"

Jan 1, 2012

By D. Pradhan, R. G. Reddy

"Electrorefining of aluminum scrap was investigated from AlCl3 –1-Ethyl-3-methyl-imidazolium chloride (EMIC) (Molar ratio 1.65) chloroaluminate electrolyte using copper cathodes at temperature of 90±3°C and cell voltage of 1.5 V. The deposits were characterized using scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The study was focused to determine the effect of electrode surface modification as well as deposition time on dendritic depositions of aluminum. Their effect on current density was investigated also. It was shown that the surface modification of electrodes reduced the dendritic depositions of aluminum. Pure aluminum (>99%) was deposited for all experiments with the current efficiency of 94-97%. The use of ionic liquids not only reduced the energy consumption but also minimized pollutant emissions (CO, CO2 etc.) compared to the commercial high temperature aluminum production.1. IntroductionAluminum electrorefining/recycling from aluminum scrap using ionic liquid electrolyte is an attractive process today because of the unique chemical and physical properties such as wide temperature range for the liquid phase, high thermal stability, negligible vapor pressure, low melting point and wide electrochemical window. But in conventional practice, melting of aluminum scrap and high temperature molten salt electrolysis makes this process more expensive and less energy intensive (average 13 kWh/ kilogram of aluminum) [1] . Although recycling scrap aluminum requires only 5% of the energy used to make new aluminum [1-2], but the green house emissions like CO2, CO and HF have to be counted for environmental reason. Approximately, 5.31 kilogram of CO2 emitted per kilogram of aluminum production in most of the US industries."

Jan 1, 2009

By C. Cánepa

In the treatment of many problems related with the optimization of a given ore dressing process, microscopic studies can provide invaluable assistance. Such studies are generally carried out through mineralogical determinations both qualitatively and quantitatively. Frequently the solution of a specific problem requires the combination of these in adequate proportions. Often the nature? of the problem poses some conditions regarding the way the microscopic determinations are made in order to yield useful information. Most publications applied to mineral beneficiation show results of ore microscopy without mentioning the methodological details involved in the determinative work and therefore it is not possible to judge their reliability and/or their relevance. As methodology must necessarily change from case to case, it is very important for the microscopist to identify first the direct and indirect mineralogical information required to solve the problem. Without such guidelines selection of methods for the qualitative and/or quantitative determinations cannot be made.

Jan 1, 1981

By Metehan Erdogan, Ishak Karakaya, Fuat Erden, Emre Ergül

"The FFC Cambridge process was suggested as a promising Si production technique for the expanding solar energy industry. Direct electrochemical reduction of bulk SiO2 plates and porous SiO2 pellets in molten CaCl2-NaCl salt mixture were investigated at 750°C by applying 2.8 V potential difference. The produced Si powder was brown and found to be contaminated by the Ni and stainless steel plates used as the cathode contacting materials. The reduction rates of the bulk SiO2 plates and porous SiO2 pellets were compared from variations of current and accumulative electrical charge that passed through the cell during the electrochemical reduction. The amorphous bulk SiO2 plates were reduced slightly faster than porous pellets of crystalline SiO2. The overall reduction potential of SiO2 pellets against the graphite anode at 750°C in molten CaCl2-NaCl salt mixture was determined as 2.3 V by cyclic voltammetry. This potential was supported by calculations.IntroductionMetallurgical grade Si cannot be directly used in electronic industry and some intermediate steps are required to produce industrial solar grade silicon (SOG-Si). A promising alternative solar grade silicon production technique is the FFC Cambridge Process [1]. Production of Si by electrochemical reduction of SiO2 at 850oC in molten CaCl2 electrolyte was first studied by Nohira et.al. [2]. In their study; Si formation was observed on bulk SiO2 cathodes after 1 hour of electrolysis. Complete electrochemical reduction of porous SiO2 pellets was first reported by Jin and his coworkers [3]. The mechanism of electrochemical reduction of SiO2 to Si in molten CaCl2 was explained in another study [4]. Reduction rates of bulk SiO2 and porous SiO2 pellets were also compared previously and it was found that reduction rates for bulk plates were higher [5]. Furthermore, it was reported that mixing Si into porous SiO2 pellet increased the reduction rate [5]. Mo [2, 4-7], Ni [3, 8, 9] or Si [6] were used as cathode contacting materials in various studies. Yasuda et. al. [6] produced Si with 99.80 % purity using Si plates as cathode contacting material to reduce metal contamination."

Jan 1, 2012

By Hiroshi Maeta, Takao Kino, Hirota Osono, Kikuo Matsusaka, Azusa Shida

"Prior to refine an ultra-high purity material, it is necessary to estimate the surface cleanness of a base material. In this report, the cleaning method of a surface for refining of an ultra-high purity aluminum has been studied. Aluminum sample of 99.999% purity was p9lished mechanically and electrically and washed with various solvents. Surface composition and a depth profile near the surface were examined. Based on the experimental results, surface structure of an ultra-high purity aluminum was discussed.IntroductionRecently, studies on high purity metals have become of interest, and we have reported .various properties of an ultra- high purity aluminum1- 2)In order to purify a metal, it is necessary to clean a work area and to make vacuous as possible. So, we are studying the purification of aluminum by an ultra-high vacuum refining system and a zone refining system set up in a clean room with cleanliness class of 1000.Now, in order to avoid a mixing of impurities into the refining metal, a surface cleanness of a base metal is very important factor. The purity of the base aluminum used our work is 99.999%, but the surface state of the base aluminum is not clear. Aims in this work .are to investigate the surface state and to obtain the cleaning method of the base aluminum.Experimental procedureSamples used in this work were 99.9% (3N), 99.99%(4N) and 99.999% (SN) aluminum produced industrially and 99.9999% (6N) aluminum purified by us."

Jan 1, 2000

By T. Goda, H. Kiuchi, M. Iguchi

"IntroductionThe utilization of silver in the electronic industry has been increasing in recent years. It is desirable that valuable metals are recovered from the used scraps of these industrial goods. Condensor chips, for example, contain silver, palladium, and Ag-Pd alloy. The dissolution behavior of silver was studied assuming that scraps such as used condensor chips in which Ag-Pd paste is used are subjected to wet treatment.ExperimentalIn this study the powder, granules, and flakes of silver were used in these nitric acid leaching experiments. The nitric acid solution was agitated in a glass reactor with a magnetic stirrer and heated to the required temperature. The experiment was started by putting the silver sample in the solution. After the leaching, the solution was filtered and the concentration of silver in the filtrate was analyzed by ICP.ResultsIn dilute nitric acid of less than 5 N, silver powder dissolved easily with increase in the concentration of nitric acid and temperature. However, the more intensive the stirring of the solution was, the lower the dissolution quantity became. Fig. 1"

Jan 1, 2000

By Daoxin Wu, Zhong Cao, Yan Shi, Yu Ding, Huanli Yang, Zhongliang Xiao

"2-substituted benzimidazole-zinc and 2-substituted benzimidazole-copper complexes were main components of organic solderability preservative (OSP) in PCB producing process and affect the thermal stability of OSP film. So these four complexes were prepared by 2-substitutedbenzimidazole reacting with zinc ion and copper ion, the complexes crystals were determined by IR, its thermal stabilities were studied by TG method. The results indicated that the thermal stability of 2-substituted benzimidazole-zinc is higher than the 2-substituted benzimidazole copper,and the thermal decomposition mechanism was presentedIntroductionImidazole compounds which is an important heterocyclic compound shows the important value and outstanding prospects[I-3l in field of biological engineering, medicine, and high-performance composites. It's said that imidazole compounds is an excellent new metal surface treatment[4] agent, because it has good reaction activity with metals and can form a chemical layer on the metal surface. The complexes of imidazole were main components of organic solderability preservative (OSP) in PCB producing process and affect the thermal stability of OSP film. The mechanism of imodazole combined with metal and film deposited has been reported, but the opinions about thermal stability of film have bifurcation, let alone the thermal decomposition mechanism of film at high temperature. The complexes were prepared by combining of 2- substituted-benzimidazole with zinc and copper iron, which were studied by IR and TG method, in order to get thermal stability of different complexes."

Jan 1, 2011

By William Brinkman, Mark Jolly, Nasim Soleimanian, Karl Dearn, Oliver Brinkman

"Glass manufacturing is a heat intensive process. There is a direct correlation between the batch distribution techniques and the furnace energy consumption, productivity, and quality of the glass manufactured. All four major segments (float, container, fibre, and specialty glasses) would benefit from using an optimised batch distribution technique where possible. Oscillating batch chargers (OBC) have been in use since the early 70s, despite their superior batch shape, coverage, and in turn positive effects on the energy consumption and productivity of the furnace they are almost exclusively used in container glass manufacturing. The OBC’s main difference compared with other charging methods is its ability to directly influence the batch initial velocity. This paper reports on results achieved in CFD models (GFM) used to study effect of the machine on the overall energy consumption in the doghouse and the melt space.IntroductionGlass manufacturing can be divided to four major segments float glass, container glass, fiberglass, and specialty glasses. The financial cost of manufacture, its impact on the environment, lack of standardisation and mounting pressure imposed by the authorities for reduction in emissions means that the industry and its suppliers are utilising CFD modelling in order to tackle these challenges. The need for high temperature to create and maintain the viscous flow, homogenisation of the glass melt, and maintenance of the process to allow continuous output of glass of the right quality are the contributors to the energy intensive activities that are involved in continuous glass manufacturing. This in turn has resulted in design of large container glass furnaces which have high energy consumption, low specific performance, and high CO2 emissions where the most efficient furnaces in the container glass sector have a specific primary energy consumption of 3.8 GJ /tonne of glass at a level of 50% cullet in the batch making even very small improvements in efficiency by operation optimisation a value adding activity [1-14].The theoretical calculated energy required to melt glass is 2 to 3 times less than the energy actually used to melt glass as a result of glass melt passing a zone 5 to 8 times before leaving the tank.[8]. This causes contamination as the result of mixing between the completely molten glass free from bubbles returning to the batch area where there is freshly molten non-homogeneous glass, still containing very large numbers of bubbles and un-molten batch. At high temperature some components are dissolved rather than melted. Given that an un-molten batch is a good thermal insulator, it can be transported a long way into the furnace, increasing the need for homogenization which also increases the glass residence time of glass melt. This is why large unbroken strings of batch should be avoided, as should an overall blanket without gaps."

Jan 1, 2014

By He Zhi-jun, Ning Zhe, Pang Qing-hai, Zhang Jun-hong, Zhan Wen-long

The effect of microwave irradiation on grinding property of coal was studied by using Hardgrove grindability index tester. Superior grindability of coal was obtained to varying extent after microwave irradiation treatment. The variation in microstructure of pulverized coal during microwave irradiation was observed by utilizing scanning electronic microscope (SEM). The results indicated that the different microwave absorbance of minerals and carbon matrix led to cracks on their interface, by which coal particles were further pulverized and therefore the granularity of coal powder was reduced. Due to the different formation process of various coals, bituminite and anthracite are very different in physical and chemical properties. According to the content of coal pulverization, it can found that microwave irradiation has a stronger pulverizing effect on bituminite in comparison to anthracite.

Jan 1, 2016

By Jiann-Yang Hwang

The economic growth in new developing countries such as China and India has stimulated strong demands in basic materials such as steel. World steel production has exceeded the milestone of a billion tons a year recently. However, the blast furnace technology, which was invented in 1340 A.D., is still the fundamental route for today?s steel production. It is important to develop a new generation of steelmaking technology that can meet the society?s needs from the energy, environmental and economic standpoints in the 21st century. The new microwave and electric arc heating technology discussed in this paper provides a totally different mass and heat transfer mechanism from the conventional blast furnace technology and offers a great potential to meet our society?s needs.

Jan 1, 2006

By S. Kurama

Incorporation of de-watering sieve waste of borax (TSW) from Etibor Kirka Borax Company (Turkey) on the mechanical and physical properties of a commercial floor tile composition was investigated. In order to achieve this aim, TSW was partially employed in place of feldspar in the standard composition up to 20 wt %. The formulated compositions were wet milled, dried, shaped and then fired at 1190C for a total firing time of 38 minutes (from cold to cold) under industrial conditions. It was found that using of TSW up to 15 wt % improved the physical and mechanical properties of final product. The results indicated a good prospect for TSW as a co-flux in floor tile formulations.

Jan 1, 2006

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By A. K. Kyllo, G. G. Richards

"The formation and control of accretions is an important aspect of process operation for gas injection. The nature of the accretion formed can have a considerable effect on a process, especially on the life of the lance or the refractories in the tuyere region. There are three basic shapes of accretion formed on tuyeres; pipes, hemispheres and hollow-cored hemispheres. However, there are wide variations within these shapes. Generally, the type of accretion formed will depend on the injector design, certain operating parameters and the physical properties of the bath materials. This paper seeks to collect the results of previous and current physical and mathematical modelling together with data gathered from operating furnaces, to obtain a better understanding of the effects of process design and operating variables on accretion formation.IntroductionAn important consideration in the design of a gas injection process is the possible freezing of the bath either around the tuyere or on the lance. With proper design, freezing may be controlled to provide protection of the lance or refractory, and to avoid blockage. Improper design may lead to tuyere blockage and significant refractory or lance erosion. In view of this, a good understanding of the heat transfer in the injection region is essential.While tuyere blockage has been a persistent problem since the inception of submerged gas injection processes, the problem of accretion formation was not studied in detail until the development of the shrouded tuyere by Savard and Lee. A number of studies relating to accretion formation have been carried out since then, but there is still little information available relating the nature of the accretion formed to the design of the injection system.The build up of materials on lances is a similar problem, and may also be either beneficial or detrimental, depending on circumstances. Unfortunately, there is even less information available regarding build up on lances than there is relating to tuyere accretions. While the form of build up on lances is generally a simple coating of the lance, accretions on tuyeres tend to be more complex. Tuyere accretions tend to occur in one of three basic forms: pipe, hemispherical and hollow-cored hemispherical (Figure 1). However, there appears to be a considerable variation within these forms."

Jan 1, 1996

By H. -Peter Sattler

The laser sorting technique for replacing the handpicking of the non-ferrous metal scrap from auto shredders was first introduced 1990, The process is based on the use of atomic emission spectroscopy induced by lasers to identify the scrap particles and sort them with adequate systems into main fractions of Al-, Zn-and Cu-alloys, stainless steel and lead, In the meantime the handling technique for the scrap, i.e. the singling and sorting technique as well as the analytical detector were further developed for more efficiency and higher reliability, i,e. less maintenance, minor sorting errors etc. These developments were mainly based, on and initiated by operational experiences from the startup phase of a first production plant. Part of the on going research work was the development of an ,aluminium detector which makes it the first time possible to sort mixed aluminium scrap automatically into specific alloy fractions.

Jan 1, 1995

By June-Yong Eom, Jong-Jin Pak, Jung-Mock Jang, Min-Kyu Paek

The nitrogen solubility in liquid Mn-Si, Mn-Si-Fe, Mn-Si-C and Mn-Si-Fe-C alloys has been measured by the gas-liquid metal equilibration technique in the temperature range of 1673-1773 K. The additions of silicon, iron and carbon significantly decreased the nitrogen solubility in liquid manganese alloys. The experimental results were thermodynamically analyzed by the Wagner’s formalism to determine the first- and second-order interaction parameters of silicon, iron and carbon on nitrogen in liquid manganese. The thermodynamic parameters can be used to predict the nitrogen solubility in ferromanganese and silicomanganese alloy melts as functions of the melt composition and temperature at given nitrogen partial pressures.

Jan 1, 2014

By Thomas Niehoff

"Oxyfuel combustion systems are state of the art for many melting operations. Airfuel systems have been stepwise modified to oxygen enrichment, oxygen lancing and oxyfuel. Every change of the melting process will have consequences with regards to emissions and energy usage. The uniqueness of many operations requires unique skills to resolve potential issues. This paper will give some examples of how airfuel systems can successfully be converted to oxyfuel.IntroductionOxyfuel technology – meaning the combustion of fossil fuels such as natural gas, oil or coal with technical oxygen instead of air for industrial melting or heating processes is widely used in many industries these days. Even though oxygen production, storage and handling has been state of the art for decades other opinions exist. Often oxyfuel is regarded with fear and potential hazards like: “Oxygen makes the process too hot.”, “Oxygen will melt away the refractory.”, Liquid oxygen is dangerous.”, “Oxygen will cause explosions.”, ……etc.Typically a more detailed discussion about a specific industrial process and how oxygen can be applied in a safe and economic way the seeming issues go away."

Jan 1, 2010