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By Binxu Zeng, Mark Jolly, Xiaojun Dai

"The traditional investment casting foundries use batch melting and chunky running systems to produce casting components. This method leaves the energy saving issue as subsidiary one. In our research project, one of the partners, the AEROMET international PLC provides the thin wall aluminium component ""filter housing"" for test. The AERO MET uses traditional casting route to produce the filter housing, which only gives 5% --10% yield. In this paper, numerical simulation method is used to analyse filling and solidification of the casting running system. The CRIMSON running system of the filter housing is designed by using casting simulation software, MAGMAS and Flow3D. By working with AEROMET, various configurations of the casting running systems were tested and analysed. Using them ultiple life cycle approach, the energy content of new process is compared with traditional one. It indicates that the CRIMSON process only uses 36% of energy consumed by the traditional route.IntroductionThe investrnent casting is a metal for ming process using expendable patterns, which is a standard casting technique and is widely used to produce quality parts. Its accuracy, versatility and integrity tie itself to important and precious engineering components in Aerospace industry. However, traditional investrnent casting process usually uses chunky runner system and gravity filling method. It not only reduces the casting yield of the product but also causes the pouring defect during the casting. As author's previous research showed that gravity filling method pouring basin and down sprue are two main resources of entraimnent defects generation. No matter how good the running system is, entraimnent defects such as double oxide films (DOF) and bubbles will I get into the casting to cause problem."

Jan 1, 2013

By Alexander A. Knminskii

Polymorphism of BaR2F8 compounds is analyzed, and some peculiarities of obtaining monoclinic low-temperature (3-BaR2F8 crystals (R=Y, Ho-Yb) and orthorhombic high¬temperature a-ßaR2F8 crystals (R=Yb, Lu) by the Bridgman-Stockbarger growth technique are discussed. We pay a special attention to BaYb2F8:Er3+ crystals, which are able to generate both 2:µm SE using the new four-level operating scheme (4F9/2?4I11/2 laser channel) and 2- and 3-µm SE by means of the cascade scheme (4F92?+4I11/2?+4I31/2). This 2-µm generation of Er3+ ions has an advantage over similar SE of Ho3+ and Tm3+ ions (especially under diode laser pumping), that is important in designing the medicine and ecology laser. We report on orthorhombic BaR2F8 crystals with the ordered structure, a new crystalline materials for generating Ln3+ ions. The growth conditions are determined and orthorhombic BaLu2F8 crystals of several cm3 in volume doped with Ce3+, Nd3+, Ho3+, Er3+, and Tm3+ ions are obtained for the first time. Spectroscopic and laser characteristics of these crystals are discussed for Nd3+-and Era+-doped samples serving as representative examples. In particular, low-threshold stimulated emission was excited in 4F3/2?+4I11/2 channel of Nd3+ ions in the BaLu2F8. Room-temperature generation was obtained also at -1.317 µm wavelength for Nd3+ and at ~2.8 µm (several lines) for Era+ ions in this new laser crystalline host with a threshold of about 20 J.

Jan 1, 1997

By Fuming Wang, Xin Lu, Hao Bai, Hebin Zhu

"In this study, CO2 emissions and carbon footprint of a typical steel works with integrated process and iron and steel industry in China was calculated and analyzed by a carbon footprint method based on the model of process CO2 emissions in iron and steel making. The carbon footprint of iron and steel industry from 1991 to 2010 in China showed a rapid increasing tendency. In 2008, the CO2 emissions of iron and steel industry in China was 1.289 billion tons, 19.71% of the national total CO2 emissions, and the corresponding carbon footprint was 159.13 million hm2 of green area. Carbon deficit of iron and steel industry also go up gradually if considering the carbon storage by green vegetation. Thus, the internal carbon reduction strategy, such as energy structure optimization and energy saving technology, was mainly encouraged for the sustainable development of iron and steel industry in China.IntroductionThe Global Warming resulting from the increase of Greenhouse Gases (GHGs), in particularly CO2, in the atmosphere has become the main reason of global climate change, and large emission reductions are required for sustainable development [ 1]. The iron and steel industry is the largest energy consuming manufacturing [2] in the world and the largest emitter of CO2 emissions. In 2005, it accounted for about 20% of global industrial energy use and 30% of energy and process CO2 emissions from industry [3]. In China, the crude steel has firmly been ranking at first of the world recent years and kept growing tendency year by year. With the production growth, the CO2 emissions of iron and steel industry also increased significantly and hence the steel industry has become one of the most sources of CO2 emission in China [4], which has attracted more and more attention to seek the carbon reduction strategies.Carbon footprint is an important and useful concept originating from Ecological Footprint, which was used efficiently to quantitatively analyze the impact of the human activities on ecological system, in particularly impact of the human energy activities [5]. In the view of Life Cycle, the carbon footprint is efficient to analyze the direct and indirect CO2 emission in the whole life of various products used in human activities. As to the iron and steel, the important materials and products in the human life, the carbon footprint analysis is quite necessary to evaluate the CO2 emission impact on the corresponding ecological system and global environmental."

Jan 1, 2013

By Yuuki Hagio, Hiroyuki Tobo, Michihiro Kuwayama, Yasutaka Ta

"Reduction of CO2 emission is necessary to remedy global warming, however, promising approaches of CO2 separation require a large amount of energy. Molten slag, which is generated as by-product of steel production, has high temperature, but its energy has not been harnessed. To recover the thermal energy from the slag and to apply to separation of CO2 are economical and environmental conscious ways. We propose a new heat recovery system, in which, molten slag is solidified continuously on water-cooled roll and the solidified slag plates are charged into counter-current heat recovery equipment. In laboratory scale experiments, heat recovery ratio of more than 30% was acchived by controlling the thickness of slag.IntroductionThe steel industry in Japan has been working on the projects of ""Environmentally Harmonized Steelmaking Process Technology Development (COURSE50)"". COURSE50 aims at developing technologies to reduce CO2 emissions by approximately 30%. One of the main technologies is to capture and recover CO2 from blast furnace gas using chemical absorbents to regenerate CO2-laden chemical absorbents by separating CO2 from the absorbents. As one of the solutions, JFE Steel Corporation has been developing sensible heat recovery process from steelmaking slag. It is effective to recover and use unutilized high temperature waste heat within a steel plant as the thermal energy required."

Jan 1, 2012

By A. Warczok

The oxidation and smelting of chalcopyrite, bomite, chalcozine and pyrite has been studied under simulated flash smelting conditions. The results of copper sulphide oxidation show that under constant oxidation conditions, the degree of oxidation drops sharply when the particle size is increased above a given range. This critical size range varies typically between 200 and 500 pm depending on the oxygen content in the gas phase. For bomite, chalcopyrite and pyrite, the critical size range increases with increasing iron content in the mineral and with increasing oxygen content in the gas phase. The extreme case is observed for pyrite in pure oxygen, where there is no effect of the particle size on the degree of oxidization. Microscopical observations of the oxidized products show the influence of different factors on the mechanism of oxidation and fragmentation of the sulphide particles. Based on microscopical analysis and phase identification of the oxidized products, a model has been proposed for the oxidation and smelting of copper sulphide particles in suspended state. The mathematical model describing the sulphide particle oxidation is supported by the obtained results. Using this model, it is possible to describe the role of particular factors in the sulphide minerals oxidation.

Jan 1, 1992

By Juan Ruiz-Ornelas, Yousef Mohassab, Ricardo Morales-Estrella, Hong Yong Sohn, Noemi Ortiz-Lara

The effect of mechanical activation on the reduction kinetics of magnetite concentrate by hydrogen was studied. The magnetite concentrate was milled for 8 h using a planetary mill. After the milling process, the average particle size was reduced from 14 to 4.4 m resulting in a lattice microstrain of 0.30. Thermogravimetric experiments were conducted to focus on the chemical reaction as the rate controlling factor by eliminating external mass transfer effects and using a thin layer of particles to remove interstitial diffusion resistance. The onset temperature of reduction was decreased due to the mechanical activation, and the degree of conversion was decreased by sintering of particles which was confirmed by SEM analyses. In view of the results, a reaction rate expression is discussed from which the activation energy is calculated.

Jan 1, 2016

By Hideki Minoura

"Two novel electrochemical techniques for the preparation of highly crystallized CdS film have been presented. One is cathodization of a conductive substrate in an acidic chemical bath containing cadmium salt and thioacetamide, where electroreduction of proton at small current densities induces a growth of highly crystallized CdS thin films, whose growth is not disturbed by the reactions in the solution phase. The other technique is electoreduction of aqueous Cd2+— SCN complex. An advantage of this technique lies in no formation of solid particles in the bulk, of the bath.IntroductionIn recent years much attention has been paid to materials preparation by solution processing because of its advantages in lowering the cost as well as the stress to the environment, as compared to the conventional gas phase techniques which unavoidably require high temperature and/or vacuum. We have been trying to explore novel techniques for preparing functionalized compound semiconductors by aqueous solution process. Semiconductors which we have been mainly focusing on are CdS and ZnO, which are important semiconductors finding applications in various devices. In the present paper, some of the techniques that we have recently established for the preparation of highly crystallized CdS will be presented.Methods of the CdS film processing in solution phase (wet process), which have been reported so far can be divided into two major groups; one is chemical bath deposition (CBD) in alkaline solution containing Cd2+ and thiourea 1)4) and the other is electrodeposition (ED) in acidic solution containing Cd2+ and thiosulfate ions - 5)-8) or organic solutions containing dissolved sulfur 9)-11)."

Jan 1, 2000

By V. E. Antonov

Hydrides of iron and iron-based alloys are thermodynamically stable only at hydrogen pressures in the gigapascal range and rapidly loose hydrogen under ambient conditions. At low temperatures, however, these hydrides can be retained in a metastable state at atmospheric pressure after being cooled under the high pressure to liquid nitrogen temperature. This review will discuss the current state of studies on phase transformations in the Fe-H and related systems and also on the composition, crystal structure and physical properties of the hydrides, both under high hydrogen pressures and in the "quenched" metastable state at ambient pressure. The studies at ambient pressure include magnetization measurements, X-ray and neutron diffraction, Mossbauer spectroscopy and inelastic neutron scattering. In the sections on Mossbauer and structural investigations of hydrides of Fe-Cr and Ni-Fe alloys new experimental results will be presented.

Jan 1, 2002

By Kun Wang, Xinhui Li, Huaqing Xie, Qingbo Yu, Qin Qin

"Three typical model compounds of bio-oil (ethanol, acetone and phenol) were studied in the steam reforming process for hydrogen production. In the thermodynamic analysis, the three componds showed the similar trends. The hydrogen yields increased with the increase of steam/carbon (S/C) ratios, and the temperatures of the maximum hydrogen yields moved afterward to low temperature zone. However, the hydrogen contents were just about 70%. For improving hydrogen yield, a new system for steam reforming of bio-oil with site CO2 capture was put forward. This system required the catalst with the larger granularity having greater mechanical strength and higher abrasion resistance. So, six Ni-base catalysts loaded on Al2O3 particles prepared were used and among them, Mg-Ni/Co catalyst showed the best catalytic performance. For the simulated bio-oil (the mixture of the compounds), the hydrogen yield can attain 63% with Mg-Ni/Co catalyst with the good stability and regeneration ability.IntroductionCurrently the interest in the use of hydrogen as a clean energy carrier is increasing, and the main way for producing hydrogen is steam reforming of fossil fuels, containing steam reforming of nature gas, naphtha and coal. But this way caused substantial amounts of CO2 emitted, and these sources of hydrogen which are non-renewable energy will eventually be used up [1, 2]. As a kind of renewable energy, biomass is recognized as an attractive alternative to fossil fuels, because of its neutral CO2 emissions [3]. There are mainly two thermochemical processes using biomass to produce hydrogen, gasification and flash pyrolysis followed by steam reforming (SR) of the biooil produced in the flash pryolysis process [4]. The latter was known as one of the most promising and economically viable methods for hydrogen production [5]. In the last decades, the biomass flash pyrolysis technology was adequately developed and fairly mature [6]. But the steam reforming of bio-oil is still at the research stage and yet has been leading to more and more concerns by the researchers. In their research, the catalysts were widely studied and yet mainly were powdery[7-10], and the reactors manily were fixed bed reactors[11-13], readly causing the carbon deposition and the catalyst deactivation, against the continuous running. In this paper, a new systerm was put forward and could realize continuous production of hydrogen, yet needed catalysts with the larger granularity having greater mechanical strength and higher abrasion resistance, as well as powdery CO2 sorbents which mainly calcium oxide based ones.In this paper, the thermodynamic analysis of the steam reforming processes of three typical bio-oil model compounds (ethanol, acetone, phenol) was performed, and the effect of S/C ratio and temperature on the hydrogen yield and the compositions of gaseous products were investigated. Then, a new systerm for steam reforming of bio-oil with site CO2 capture was put forward, and the catalysts with a certain granularity were prepared and studied."

Jan 1, 2014

By Mark Jolly, Nasim Soleimanian

"During the last 20 years CFD (Computational Fluid Dynamics) has been used as a tool to aid furnace designers and manufacturers to improve energy efficiency and effectiveness of glass furnaces. However as the models are maturing the effect of feeding equipment used to push the raw material into the furnace has not been included in the process models. This paper investigates the effects of batch pattern in the melt space caused by charging equipment on the energy efficiency of the furnace focusing on the melting zone. A simple batch patterns sensitivity study has been performed using purpose built software (Glass Furnace Model-GFM). It is concluded that in order to further reduce the energy consumption of the furnace it is necessary to model the batch charging process in more detail to find more opportunities for improvement.Introduction Glass manufacturing is a conservative industry which applies to all the four major segments (float glass, container glass, fiberglass, and specialty glasses). Risks due to the high capital investment, very long service life of the furnaces, and the demand for high performance and quality from the outset translates into evolutionary progress rather than revolutionary. The main problem facing glass manufacturers are the financial cost of manufacture, its impact on the environment, and mounting pressure imposed by the authorities for greener manufacturing and reduction in emissions.The main energy intensive activities involved in continuous glass manufacturing are: the need for high temperature to create and maintain the viscous flow, homogenisation of glass melt (melt residence time), and maintaining the two to achieve continuous output of glass at the right quality. The high temperature and long duration of homogenisation has resulted in the design oflarge furnaces, which have high energy consumption, low specific performance, and high C02 emissions. As an example in the container glass sector the most efficient furnace has a specific primary energy consumption of 3.8 GJ /tonne of glass at a level of 50% cullet in the batch. Even very small improvements in efficiency by optimising operation would have a high impact [1-14]. Given the conservative nature of the industry and the costs involved in experimental data gathering, CFD modeling of the process has been used extensively during last two decades to not only improve our understanding of the process but also as a tool in predicting possible optimisation windows, e.g. Glass Furnace Model ( GFM), a commercially available piece of software that has been developed to optimise furnace operation."

Jan 1, 2013

By M. Suzuki, M. Dobashi, M. Kahata, T. Yoshida

Almost 30% of steel in Japan is produced by electric arc furnace (EAF) treatment of iron scrap. EAF dust includes approximately 20 wt % of Zn and 3- 5 wt % of CI and is treated by the pyrometallurgical processes to recover Zn as Zn oxide. Direct hydrometallurgical processing is one of the most effective methods to recover high purity Zn. In this case, CI in the EAF dust is dissolved in the liquid phase by leaching, and the CI anion in electrolyte attacks anodes which are commonly made of a lead base alloy. Several processes have been proposed to remove CI anions from acidic sulfate solution. In this study, an electrolytic process was examined to eliminate CI anions from Zn sulfate electrolyte. From our study it can be said that the elimination rate of CI anion depends on the anode material ( i.e., the elimination rate is Pb-Ag alloy == Pb > DSE== Pt). In industrial Zn electrowinning process, the electrolyte contains Mn, which means the influence of Mn should be considered in the elimination of Cl. Mn dioxide deposition on an anode plate reduces the efficiency of CI removal. A periodical reverse current electrolytic system was examined to prevent this efficiency decrease, and deposited Mn dioxide could be removed very rapidly when the current is reversed. More than 95% of CI anion could be removed by this method in a shorter period than direct current method.

Jan 1, 1997

By Karl A. Gschneidner

The magnetocaloric effect has been known for 120 years and has been utilized for cooling about 70 years. But in the last four years significant advances have been made to show that magnetic refrigeration is a viable and competitive cooling technology. Most of the work has focused on reciprocating devices, but rotary apparati are being developed. To date the magnetocaloric properties have been characterized for more than 200 materials. The magnetocaloric effect behaviors have been classified into three types of behaviors. The most common one is found in magnetic materials which exhibit a second order magnetic phase transition. Magnetic materials which exhibit a first order magnetic phase transition account for the second group of materials. Materials which exhibit multi-magnetic phase transitions make up the third group. The best candidate materials for magnetic cooling over the range from -4 to -1 350 K are also presented.

Jan 1, 2002

By I. Gaballah

About forty percent of the SOx emissions are generated during the processing of metal sulfides of Cu, Pb, Zn, Ni, etc. Although new technologies for metal sulfide's smelting allow the production of H2S04 with a reasonable cost and decrease the emissions of sulfur oxides, the generated quantity of SOx is considered as a serious threat to environment. This paper suggests alternatives for low temperature processing of complex sulfide ores or concentrates 'CSO or CSC' under neutral, reducing and chlorinating atmospheres or their combination. At T > 400 "C, The neutral and reducing treatments allow the decomposition of pyrite and the partial recovery of sulfur as So and H2S. At 300 "C, the chlorinating treatment of CSC is fast, exothermic and allows the separation of FeC13 from the valuable elements' chlorides. It also generates SyCIx that can be either reduced by H2 or hydrolyzed in presence of sodium sulfide. The recovery rate of elemental sulfur with respect to the sulfur input exceeds 90 %.

Jan 1, 1999

By Hideaki Tokuyama

Recovery of Ni from acidic wastewater of metal surface treatment has been investigated for reuse of the metal and water. Ion exchange equilibria between Ni ion and a strong acid cation resin, DIAION SKIB, and effective diffusivity in resin particle have been studied and they related to the concentration of HCI. The amount of adsorbed Ni for unit quantity of resin decreases with the increase in HCI concentration. This trend is remarkable for acid concentration above 0.1 kmol/m3,. The exchanging ratio of Ni2+ to H+ in resin particle is I/2 and the values of equilibrium coefficient K and maximum exchange capacity Q are I.62 and 3.16 keq/m3 -dry resin, respectively. Effective diffusivity D. determined from the observed breakthrough curve increases with increasing concentration of DC!. A prototype of moving bed has been developed and applied for the recovery of Ni from model solutions of wastewater prepared by mixing HCl and NiCl2. This apparatus allows us to control the resin flow rate by changing the cross sectional area of hole I the Teflon plate installed at the bottom of resin bed. Characteristics of Ni recovery have been clarified under various liquid flow rates. In any case for Q1, Ni ion has been effectively recovered on SKIB resin and the removed fraction was more than 99.5 %. Higher loading ratio of ion is attained at larger liquid flow rate.

Jan 1, 2003

By Yuri Gelfgat

"The report presents the results of theoretical and experimental investigations of the MHD method used for production of composite materials from immiscible melts, e.g., Al-Pb, Zn-Pb, Bi-Ga and others, which, when solidified, can be presumed as ""frozen emulsions""IntroductionThe searching of the methods for controlling the phase distribution in various liquid heterogeneous media is one of urgent tasks in modem material science. The studies [1-3] have revealed that in case of electrically conducting media the influence of electromagnetic body forces on the liquid can be a rather effective mean of such a control. The current paper investigates some physical conformities governing the behaviour of binary liquid metal systems with a immiscibility region under electromagnetic processing designated to produce ingots with homogeneous structure.The main idea of the proposed method rests upon a concept that the electromagnetic forces in the melt are similar to gravity forces due to buoyancy effects in space and have a selective ability to influence the melt components dependent on their conductivity. In crossed electric E and magnetic B fields (fig.I) each component of the medium is influence by the force density f = jXB, where the current density j is determined by the conductivity a of the component j = -oE. When this force is directed parallel or non-parallel to the gravity vector, the buoyancy of suspended particles can be controlled accordingly.This phenomenon allows one to create a situation in binary system, when the sums of all mass forces (gravity and electromagnetic) affecting every component are equal, and two components are under conditions of equilibrium with respect to each other. These conditions are called quasiweightlessness, which is generated in the melt by the electromagnetic forces."

Jan 1, 1998

By Hiroshi Ono

"By newly developed ICP method, trace amounts of As(III), As(V) .,Sb(III) and Sb(V) were precisely determined within accuracy of sub ng/ml. As(III) and Sb(III) were separated from As(V) and Sb(V) by extracting into ·xylene as diethyldithiocarbamate complexes using diethylammonium diethyldithiocarbamate (DDDC), and then back-extracted into nitric acid for a quantitative determiruition by ICP-AES equipped with hydridegeneration system The recoveries of As(III) and Sb(III) were satisfactory throughout the extraction with 0.04mol/l DDDC in xylene from lmol/l hydrochloric acid solution and the back-extraction with 7 mol/l nitric acid. As(V) and Sb(V) were reduced to As(III) and Sb(III) by ascorbic acid and potassium iodide, and their quantities were determined as mentioned above. The detection limits were found to be 0.58ng/ml for As(III), 0.63ng/ml for Sb(III) using 50ml of a sample. The proposed method was applied to analysis of the real sample.Introduction In drain, arsenic(AS) concentration is prescribed below 0.lmg/l, so As must be removed. As is existed at .the form of As(III) or As(V) in solution. For t1Jeir difference of chemic;µ property, it is not easy to remove As in solution. So it is an urgent necessity to develop for determining concentration of As(III) and As(V). Antimony( Sb) has resemblance .chemical property to As. So Sb was experimented the same as As.The separation and determination of As(III) and As(V) have been carried out using several methods, such as ICP after copreclpitating separation, HPLC, direct hydride generation atomic absorption. However these methods have some problems. One of main problems is that HPLC and direct hydride generation atomic absorption methods are influenced by coexisting elements."

Jan 1, 2000

By Takamasa Ishigaki, Gervais Soucy, Mohamed Rahmane

"The induction plasma jets employed for the in-flight nitridation of molybdenum disilicide (MoSi2) powders were investigated in terms of their flow characteristics. The present study shows the effect of the operating parameters of the plasma torch, as used for this process, on the plasma jet properties. The enthalpy probe techniques, along with mass spectrometry, were employed for the measurement of the jet temperature, velocity and concentration fields. The measured values were compared to the results of a numerical simulation performed on the plasma flowing inside the torch-reactor system. The process operating conditions studied were the plasma plate power, chamber pressure and sheath gas composition. The optimal conditions for effecting the nitridation process using thermal plasma are obtained at moderate plasma plate power, at around atmospheric pressure and by using a mixture of argon and nitrogen as the plasma torch sheath gas.IntroductionMolybdenum disilicide (MoSi2) based composites are considered to be one of the most promising candidates for high temperature structural material applications [!], especially because of their high melting points, good oxidation resistance and relatively low cost. However, the wide application of these composite materials is still limited by some factors such as their brittleness at room temperature and lower strength at high temperature (> 1500 K). To overcome such limitations, a number of researchers [2-4] have earlier studied various kinds of reinforcements for MoSi2, e.g. oxides, silicides and nitrides. More recently, Fan and coworkers [5-9] have demonstrated the possibility of in-flight nitridation and carburization of MoSi2, using a thermal plasma process. This work has confirmed the plasma synthesis route as one of the most promising methods for creating an in-situ second phase structure. Properties of the plasma flow, such as its temperature, flow velocity and composition, are of crucial importance for the nitridation of MoSi2 powders during their flight in the plasma. Therefore, the optimization of such a process involving plasma· generated reactive species necessitates a thorough understanding of the plasma flow characteristics."

Jan 1, 2000

By Ragnhild Aune

In fire refining of copper, the affinities of various impurity elements on dissolved oxygen is of great significance. Further, in the design of oxygen probes in liquid copper, the influence of solute interactions on the activity of oxygen need to be considered in order to evaluate the oxygen concentration in molten copper. The present paper presents a series of measurements of the activities of oxygen in liquid Cu-M-o alloys (where M stands for Mn, Zn, As, Se or Te) carned out by the present group employing the solid electrolyte galvanic cell technique. Extreme care was taken to control the oxygen potentials in the inert gas atmosphere, and to keep the oxygen levels very low in the molten metal. The oxygen content was determined by analysis of the samples taken out from the melt. The results obtained showed that Mn has a strong negative influence on the activity coefficient of oxygen in liquid copper. A similar, but less prominent effect was observed in the case of Zn. Arsenic had no influence on the activity of oxygen in Cu (liq.). Se and Te had slight negative effect on oxygen activities in copper at XQ >10-5, while at lower oxygen levels the interaction coefficients were found to be positive. The results obtained were compared with empirical models for the calculation of interaction coefficients available in literature.

Jan 1, 2003

By J. M. Floyd

"Top submerged lance furnace developments started in CSIRO in the early 1970s and was given the name Sirosmelt. In the early work the technology was developed for tin smelting and processing tin slags but once a small pilot plant was established other slag processing applications were soon recognised and evaluated for various copper, nickel, zinc and cobalt-containing slags. The process was tried for copper smelting and converting, which was proven in the small pilot plant in 1978. In the same year the first commercial application of the technology was established for the recovery of tin from slags at Associated Tin Smelters, Sydney. Work on lead smelting was initiated by the CSIRO team in the late 1970s and laboratory work led to pilot plant trials by Mount Isa Mines.In the second decade of the technology the focus of development became commercial acceptance of the technology through marketing, development and application by Ausmelt and Mount Isa Mines; the former commercialising and developing the technology for a wide range of applications, while the latter concentrated on its own commercial needs of copper and lead smelting. This decade saw a number of commercial plants built in Australia, with considerable interest becoming evident from other parts of the world. Towards the end of this decade Mount Isa also entered into the business of marketing of the technology through rights dating to the joint work with CSIRO in the late 1970s.So far, after five years, the third decade of the technology has been characterised by diversification of applications of the technology to areas outside the non-ferrous and precious metals production industry. The waste processing and recycle industry and the iron and steel industry have recognised that the top submerged lancing system is a new type of reactor with many significant features which provide new opportunities for processing a range of materials under good environmental controls in a cost effective manner.I hope this audience will excuse my boldness in talking about the third decade of the technology when we are only half way through! I am aiming in this paper to not only talk about the past, but to try illustrate the future directions which I envision."

Jan 1, 1996

By Taiping Lou

The effects of slag composition, additive agents, and heat treatment conditions on the perovskite (CaO ? TiO2) crystal morphology, the precipitation behavior, the crystal growth and the volume fraction (VF) in the Ti-bearing blast furnace slags were investigated. The morphology of perovskite is dispersed dendriform in molten slags. The crystal growth mechanism of the remelting of fine dendrites and the coarsening of larger grains exists throughout the solidification of molten slags. With the temperature decrease, the VF was increased and Perovskite transformed from fine dendrites to coarsening ones or equiaxed grains. The lower cooling rate can increase the VF and coarsen the grain obviously, while higher cooling rate will decrease the VF and reduce the average equivalent diameter (AED) of Perovskite. When .increasing the content of CaO and Fe20}, the VF can increase obviosly. However, high basicity will give rise to the increasing of viscosity of slag, which result in the reducing of the AED. The experimental results showed that additive CaF2 and MnO can efficiently decreased the viscosity of the slags, and obviously improved the morphology of perovskite and promote growth.

Jan 1, 2000