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By Malti Goel

"Ferrous and Non-ferrous industry in India is undergoing a transition to meet the growing demand and a new thrust to Research & Development (R&D) is mounting. On one hand, to meet the target laid by the policy in the Iron and Steel sector of 110 million tones production by 2020; on the other, innovations taking place in light metal production technology; both have necessitated greater attention to development of industrial ecological framework. Industrial ecology provides a number of new challenges as well as opportunities for the industry. The development and growth in a particular industry should have a trend towards reduced energy consumption, reduced resource consumption, thereby reducing the cost of production. Technology management strategies will have a key role in achievement of these targets. The paper describes recent developments in technology management, importance of R&D and case studies on adoption of energy efficient & CO2 reduction technologies in metal industry in India. In the end suggestions for future are made.IntroductionInternational Energy Agency [1] has assessed that nearly one third of the World’s energy consumption and 36% of CO2 emissions are attributed to manufacturing industries. In case of ferrous and non-ferrous metals, the resource equality and product quality finally determine the energy share across the countries. In the overall, Iron & Steel industry accounts for about 19% of total industrial energy used. The saving potential for non-ferrous metals is estimated to be anywhere between 13 to 25 % of the energy consumed depending on the level of resource quality. The projections are that energy consumption worldwide in Industry sector would increase 1.8% per annum up to 2030 on average, and up to 2.5% in developing countries."

Jan 1, 2008

By Manjie Li, Mingrui Yang, Haijun Peng, Shuxing Qiu, Wei Liu, Shengfu Zhang

It is important to produce and utilize highly reactive coke in order to reduce the energy consumption and CO2 emissions through improving shaft efficiency in blast furnace. The present study aimed to investigate the transformation of iron minerals and properties of iron coke (the coke mixed iron ore fines). Along with the increase of iron ore fines, cold strength displayed a slight downtrend and the pore structure wasn’t inferred to be a major factor affected the properties of iron coke. During carbonization, the majority of mixed iron oxides were reduced to metallic iron by CO and H2 and the degree of metallization achieved to approximately 75%. Nevertheless, produced metallic iron was oxidized by pure CO2 during gasification. Iron coke reactivity index (ICRI) was obviously enhanced and the iron coke strength after reaction (ICSR) drastically decreases, which were also significantly influenced by crystal structure of carbon.

Jan 1, 2015

By Yuan She, Qihang Liu, Keng Wu, Hailiang Ren

By observing different coal char’s microstructures and microscopic morphologies during the coking process, the characteristics of COREX coal char’s microstructure and properties were analyzed. MCRI and MCSR were used to respectively describe the reactivity and the strength after reaction of coal char, with those of BF’s coke for reference, and then the physical meaning of MCRI and MCSR were given. MCRI and MCSR were determined by the composition of coal char. For the two kinds of COREX coal, the formula to forecast the hot performance of coal char was set up by making a multiple linear regression between the hot performance and microstructure of the coal char at 1100℃, and the predictive values of coal char’s hot performance at 600℃, 800℃ and 1000℃ coincided well with the measured values.

Jan 1, 2015

By Gregory A. Knapp

Treatment of industrial wastewaters generally advances with specific chemical concentration and mass-flow targets, established by National Pollutant Discharge Elimination System (NPDES) permits. Treated discharges must also address toxicity to test and receiving water organisms. Various parameters might need consideration during treatment design and planning, such as the known toxicants, hardness, alkalinity, solids, nutrients, metals in both the dissolved and particulate state, and even flow. Since toxicity is used as a "catch all" regulatory monitoring tool, design of treatment systems should focus on the various factors contributing to toxicity.

Jan 1, 1996

By J. A. Bustnes

The present work deals with kinetic studies of the reduction of molybdenum- and tungsten oxides by hydrogen. The experimental method used was therrnogravimetry under isothermal as well as non-isothermal conditions. The non-isothermal kinetics in the case of the reduction of MOO, to Moo2 has been modeled considering surface reaction as rate- controlling. In the case of the reduction of W02 to W a model was developed on the basis of the movement of the reaction front. The activation energies calculated on the basis of the models were in good agreement with those derived from isothermal experiments.

Jan 1, 1994

By H. Y. Sohn, Joshua E. Ramos, Moo Eob Choi

"A new technology for ironmaking based on direct gaseous reduction of iron ore concentrate is under development. This technology would drastically lower CO2 emission and reduce energy consumption by nearly 38% of the blast furnace requirements. Experiments were performed using iron oxide concentrate at 1150oC in a bench-scale facility, which was the highest temperature that could be reached in the facility. The reduction extent was determined at residence times of 3.5 - 5.5 seconds in which the reduction extent approached 43% with 0% excess H2 and 95% with 860% excess H2. Separate kinetics measurements showed that the rate is much faster at 1200 - 1400 oC. Experiments were also carried out using syngas (mixtures of H2 + CO). About 90% reduction in 3.5 seconds with 860% excess hydrogen contained in the syngas demonstrated sufficiently fast reduction for a suspension process and the feasibility of usingsyngas instead of pure hydrogen.IntroductionDespite the improvements in the modern blast furnace (BF) process, it suffers from many drawbacks. The process requires the feed in the form of sinters or pellets and high-grade coking coal. Thus, BF iron production is projected to decrease gradually [1]. The main factors for this are the environmental regulations [2] and the high capital investment cost.A large number of new ironmaking technologies have been developed or are under development [3]. Most of these processes, however, are not sufficiently intensive to replace the blast furnace because they cannot be operated at high temperatures due to the sticking and fusion of particles. Therefore, a new technology is under development for producing iron directly from fine concentrates by a gas-solid suspension technology, which would reduce energy consumption by about 38% of the amount required by the blast furnace and drastically lower environmental pollution, especially CO2 emission, from the steel industry."

Jan 1, 2009

By N. D. Schupp

The Doe Run Company's Herculaneum, Missouri lead smelter has existed in continuous operation since 1892. Throughout the history of the plant extensive developments have been made to improve throughput, increase productivity, decrease operational costs and improve technology, while remaining an environmentally responsible producer of high quality primary lead in the international market. This paper provides an overview of the Herculaneum smelter, focusing on the most recent configuration of the operations. The paper includes discussion on all the aspects of primary lead production at the Herculaneum smelter.

Jan 1, 2000

By Mark Tjerkstra

In ,1993, the WMC Resources Ltd.-owned Kalgoorlie Nickel Smelter, underwent a capacity upgrade. This capacity increase was offset by .air quality control restrictions limiting the smelter's availability to 80%. As the direct. result of this limitation, WMC Resources Ltd commissioned a double absorption contact ,acid ,plant for the desulphurisation of furnace waste gas in August 1996. The history and the impact of the acid plant on S02 emissions and air quality is reviewed. General descriptions of the other aspects of the Kalgoorlie Nickel Smelter's Environmental Project are also included in the paper. Information on 'the design features? and operating practices that relate to or contrast with practices at operations visited by KNS personnel prior to acid plant commissioning provide the paper's focus. Smelter operation has changed markedly from unstable operation prior to 1997 to continuous" operation with little down time due to mechanical or process failures resulting in increased smelter availability to more than 90%

Jan 1, 1998

By Masatoshi Ogasawara

Saganoseki smelter & refinery operated two flash smelting furnaces, producing a combined 330,000 metric tons per year (hereinafter mtpy) of copper. [n 1996, however, it successfully shifted to a single fumace operation while maintaining production at the same level. Since then, the production capacity has been further increased to the present 470,000 mtpy by technological improvements. Also, in order to reduce the converter load which represents a bottleneck in efforts to increase production, the matte grade was gradually increased and currently runs at 65 to 66% attaining the low copper content in the slag (hereinafter slag loss) of 0.7 to 0.8%. This ' paper introduces some improvements, recent operation results and thermodynamic analyses.

Jan 1, 2003

By E. Bélisle, Christopher W. Bale, S. Petersen, C. Robelin, K. Hack, J. Melançon, G. Eriksson, A. D. Pelton, P. Chartrand, S. A. Decterov, I. H. Jung, A. Gheribi

The FactSage® package consists of a series of information, database and calculation modules that enable one to access pure substances and solution databases and perform thermochemical equilibrium calculations. FactSage was originally founded by process pyrometallurgists and has since expanded its applications to include hydrometallurgy, electrometallurgy, corrosion, glass technology, combustion, ceramics, geology, environmental studies, etc. With the various modules one can perform a wide variety of thermochemical calculations and generate tables and graphs of complex chemical equilibria and phase diagrams for multicomponent systems. This paper presents examples of recent and current developments in FactSage in areas of particular interest to Dr. David Robertson. These include both ferrous and non-ferrous processing, as well as solidification and refining simulation. The paper also includes reference to the Internet Fact-Web education package.

Jan 1, 2014

By R. Hurman Eric

The dew-point technique of activity measurements take advantage of the volatility of a component in solution. The pressure of the volatile component over a sample is determined from observations of the temperature at which condensation of the vapor occurs. The method is applicable best when the vapor pressure of the components would differ by about two to three orders of magnitude. Experimentally, this is a closed system involving the use of evacuated and sealed transparent quartz sample probes. Furthermore reliable vapor pressure data of the volatile component is essential along with a specialized high temperature furnace capable of giving reproducible results. In this context, the vertical Dew-Point Furnace (DPF) was designed and built after elaborate trails until enough proficiency was gained for reprodueible results. Over the years the DPF was modified and improved. The DPF developed was versatile and could easily be used for activity measurements in the isopiestic mode (another method of measuring activities of a volatile component in a solution). The necessary ancillary systems; namely evacuation-flushing-evacuation followed by sealing of quartz sample probes under vacuum were also perfected over the years. As and when necessary the dew-point technique was supplemented by classical equilibration-quenching method employed on the sealed quartz sample probes to reveal necessary phase equilibrium information. The following were studied utilizing the above technique: (i) Activities in CuzS-PbS and FeS-PbS binaries and CU2S-FeS- PbS ternary at 1200°C; (ii) Activities in CuzS-SnS and FeS-SnS binaries and Cu2S-FeS-SnS ternary at 1200°C; (iii) Phase equilibria and thennodynamic in Cu-Pb-S, Fe-Pb-S, Fe-Sn-S, Cu-Sn-S and Ag-Sn-S systems. Most recently the following systems have been tackled: (i) Phase equilibria and thennodynamics in the Ag-Pb-S and Sn-Pb-S systems; and (ii) Activities in Ag2S-FeS-CuzS-PbS quaternary at 1200°C.

Jan 1, 2003

By Fuqiang Zheng, Yufeng Guo, Pengfei Li, Guanzhou Qiu, Tao Jiang, Andrew Yakovlevich Travyanov

Low content of TiO2 and high impurities content of Ca and Mg are the shortcomings of domestic ilmenite. To meet the requirements of the material in the titania produced by chlorination process and titanium sponge industry, enrichment of ilmenite is necessary. In the process of enriching ilmenite, high temperature and reductive condition were beneficial to the formation of anosovite, but the high content of magnesium oxide which was solid soluble in anosovite baffled the following separation. So the effects of pre-oxidation and reductive conditions including reduction temperature, reduction time and hydrogen concentration on the phase composition and metallization rate were studied. The characteristics of reduction samples were analyzed by X-ray diffraction and optical microscope. Results have shown that the reduction product is mainly composed of Fe, Fe(Mg)TiO3 and TiO2 at 1123K, its metallization rate is about 65%,magnesium exists in Fe(Mg)TiO3.

Jan 1, 2015

By R. Hurman Eric

The dew-point technique of activity measurements take advantage of the volatility of a component in solution. The pressure of the volatile component over a sample is determined from observations of the temperature at which condensation of the vapor occurs. The method is applicable best when the vapor pressure of the components would differ by about two to three orders of magnitude. Experimentally, this is a closed system involving the use of evacuated and sealed transparent quartz sample probes. Furthermore reliable vapor pressure data of the volatile component is essential along with a specialized high temperature furnace capable of giving reproducible results. In this context, the vertical Dew-Point Furnace (DPF) was designed and built after elaborate trails until enough proficiency was gained for reproducible results. Over the years the DPF was modified and improved. The DPF developed was versatile and could easily be used for activity measurements in the isopiestic mode (another method of measuring activities of a volatile component in a solution). The necessary ancillary systems; namely evacuation-flushing-evacuation followed by sealing of quartz sample probes under vacuum were also perfected over the years. As and when necessary the dew-point technique was supplemented by classical equilibration-quenching method employed on the sealed quartz sample probes to reveal necessary phase equilibrium information. The following were studied utilizing the above technique: (i) Activities in CU2S-PbS and FeS-PbS binaries and CU2S-FeS- PbS ternary at 1200°C; (ii) Activities in Cu2S-SnS and FeS-SnS binaries and Cu2S-FeS-SnS ternary at I200°C; (iii) Phase equilibria and thermodynamic in Cu-Pb-S, Fe-Pb-S, Fe-Sn-S, Cu-Sn-S and Ag-Sn-S systems. Most recently the following systems have been tackled: (i) Phase equilibria and thermodynamics in the Ag-Pb-S and Sn-Pb-S systems; and (ii) Activities in Ag2S-FeS-CuzS-PbS quaternary at 1200°C.

Jan 1, 2003

By Pinakin C. Chaubal

Today?s steel industry is in a vibrant and resurgent mode. This transformation has been in the making for some time now. Over the last few decades, the industry was steadily transforming itself into becoming a high tech industry. New technology was adopted, efficiencies were enhanced, lean manufacturing concepts were brought in and a strong customer focus was developed. Today?s mills employ sophisticated instrumentation, computerized monitoring, on-line smart systems etc. driving processes that are producing at rates of many tons/minute. All this is not possible without judiciously using the latest available technologies in various fields and developing a more sophisticated work force. Prof. Sohn has been a pioneer in driving the concept of process engineering in process metallurgy. In this paper the focus is on some aspects of process engineering ? primarily process modeling - as applied to iron and steelmaking processes. Examples are shown to demonstrate how problems have been addressed. Some thoughts on future directions are presented.

Jan 1, 2006

By Jorge Gibson, P. Chris Pistorius, Megha Jampani

"The main reason for the significant carbon intensity of integrated steelmaking (approximately 1.8 tons of CO2 per ton of steel) is the use of carbon-based reductants in blast furnace ironmaking. Several changes to blast furnace ironmaking have been proposed as ways to reduce carbon intensity and cost. A conceptually simple two-zone blast furnace mass and energy balance can be used to quantify the expected impact of such process changes on coke rate, carbon intensity, and productivity. Examples to be discussed include top gas recycling, combining lower blast temperatures with increased coal injection to produce a rich top gas, using prereduced feed, and tuyère injection of natural gas. The use of the operating window – which illustrates how allowable flame temperatures and top-gas temperatures constrain feasible oxygen enrichment levels – is illustrated. Increased use of natural gas would lower the carbon intensity of blast furnace ironmaking.IntroductionBecause of the significant carbon intensity of steelmaking (approximately 1.8 tons of CO2 emitted per ton of steel produced) and the high production rate of steel (more than 1.4 billion tonnes per annum), steelmaking is responsible for a large percentage, approximately 6.7%, of world anthropogenic CO2 emissions [1]. By far the largest input of the carbon into conventional steelmaking is as coke, which is essential to blast furnace ironmaking. A typical fuel rate for blast furnace ironmaking is 450 kg of fuel per tonne of hot metal (THM). (""Fuel"" includes coke and injectants which partially replace coke; pulverized coal and natural gas are typical injectants.) Assuming the fuels to contain 90% carbon on average, and since nearly all of this carbon exits the steel plant as CO2, a fuel rate of 450 kg is equivalent to a CO2 intensity of 1485 kg/THM – by far the largest part of the total CO2 intensity of steelmaking.Blast furnace ironmaking is expected to remain the main source of new iron units; this paper gives some estimates of the extents to which further reductions in carbon intensity from blast furnace ironmaking is possible. A recent European assessment suggested that blast furnace process intensification options such as increased pulverized-coal injection or natural gas injection would yield only modest energy savings [2]. However, if the focus is on CO2 emissions rather than on total energy use, there would be an advantage to using fuels – such as natural gas – which have lower carbon contents relative to energy content."

Jan 1, 2014

By Lin Zhu, Zheng Wei, Meng Li, Xueli Cao, Hanying Wen, Guodong Shi, Lei Yu, Wen-xin Tang, Tao Li

Low energy electron microscopy and photoemission electron microscopy (LEEM/PEEM), as powerful in-situ surface-sensitive electron microscopy, find wide applications in surface physics, chemistry and catalysis. The high reflectivity of incident low-energy electrons (0–100 eV), allows it to image the surface structures in the topmost few atomic layers within less than one second, while the sample can be heated up to 1200 °C in real time which is potentially very useful in metallurgy and materials fields. A unique three-prism aberration correction (ac-) LEEM was commissioned successfully in Chongqing University, with a lateral resolution below 2 nm. A multiple gas source in the ac-LEEM system was installed as well, which allowed us to observe chemical reactions of nanoscale mineral powders on metallic substrates. In this paper, the latest results on the applications of this three-prism ac-LEEM on oxidation and reduction processes on copper and iron polycrystalline surfaces are demonstrated.

Mar 1, 2018

By Yilin Fang, Alain Bonneville, Timothy. D. Scheibe, Zhijie Xu

"We present a hydro-mechanical model for geological sequestration of carbon dioxide. The model considers the poroelastic effects by taking into account the coupling between the geomechanical response and the fluid flow in greater detail. The simplified hydro-mechanical model includes the geomechanical part that relies on the linear elasticity, while the fluid flow is based on the Darcy's law. Two parts were coupled using the standard linear poroelasticity. Analytical solutions for pressure field were obtained for a typical geological sequestration scenario. The model predicts the temporal and spatial variation of pressure field and effects of permeability and elastic modulus of formation on the fluid pressure distribution.IntroductionIn order to achieve a substantial reduction of CO2 emissions and alleviate the atmospheric carbon problem, massive scale carbon sequestration is required involving millions of tons of carbon dioxide injection over several decades. The geomechanical response is important upon the injection of substantial supercritical carbon dioxide into deep geological formations. Supercritical CO2 is less dense than brine waters and the buoyancy driven flow of CO2 requires the aquifer to be capped by low permeability rock (""caprock"") to prevent the upward migration of C02 (as shown in Fig.1 ). Massive scale injection of C02 changes the overall stress state in the caprock and formation. This change leads to large deformation that can damage the caprock, create fractures, and open new flow paths for supercritical C02. Therefore, a coupled hydromechanical model becomes essential for the caprock integrity analysis."

Jan 1, 2012

By B. R. Westphal

The Integral Fast Reactor (IFR) concept being developed by Argonne National Laboratory is based on the pyrometallurgical processing of spent nuclear metallic fuel with subsequent fabrication into new reactor fuel by an injection casting process. During fabrication, a dilute scrap stream containing uranium alloy fines and broken quartz (Vycor) molds is produced. Waste characterization of this stream, developed by using present operating data and chemical analysis, was used to evaluate different uranium recovery methods and possible process variations for the return of the recovered metal. Two methods, comminution with size separation and electrostatic separation, have been tested and can successfully recover over 94% of the metal. Recycling the recovered metal to the injection casting process was evaluated for the different economic and process impacts. The physical waste parameters and the important separation process variables are discussed relative to their effects on the viability of recycling the material. A discussion of the criteria that is being used to establish the acceptable operating limits is also presented.

Jan 1, 1992

By Frederick T. Wallenberger

"Laser assisted chemical vapor deposition (LCVD) is a new containerless fiber process whereby growth of small diameter fibers or microstructures (microsprings, microsolenoids) occurs directly from the vapor phase. The laser beam has a focal point adjusted to coincide with the tip of the growing fiber inside the reaction chamber. Since the growing fiber is not in contact with reactor walls or foreign materials, it is chemically pure, and suitable for optical uses and uses requiring high structural uniformity. Continuous fibers and multifilament yams are possible. The use -of high reaction chamber pressures (1-10 bar) and a small wavelength Nd-YAG laser made it possible to fabricate small diameter fibers at growth rates >1 mm/s. This paper describes the synthesis of single crystal, polycrystalline and amorphous fibers by LCVD, and provides a comprehensive analysis of phase transformations occurring during their fabrication.IntroductionLaser assisted chemical vapor deposition (LCVD) is a new containerless fiber process [1-10] whereby growth of small diameter fibers or microstructures occurs directly from the vapor phase. The laser beam has a focal point adjusted to coincide with the tip of the growing fiber in the reaction chamber (Figure 1). The diameter of the growing fiber corresponds to that of the laser focus. Depending primarily on the laser energy (Le., the temperature at the growing fiber tip), it is possible to obtain single crystal, poly crystalline or amorphous fibers by this method.Since the growing fiber is not in contact with reactor walls or foreign materials, it is chemically pure, and suitable for optical uses and uses requiring high structural uniformity. Laser assisted CVD is a potentially continuous process; continuous fibers and multifilament yams are possible."

Jan 1, 1994

By Zhao wen Wang, Ramana G. Reddy, Min Li

"The electroreduction of Co(II) in l-butyl-3-methylimidazolium tetrafluoroborate (BMlMBF4) ionic liquid was investigated by cyclic volatrnmetry at 353 K. The results show that the reaction of Co(II) to Co is irreversible in one step with two electrons transferred. The diffusion coefficient of Co(II) was estimated to be 7.6 x 10-8 cm2 s·1 at 353 K. Then the electrodeposition of cobalt was studied at different cathodic potentials (-0.80 to -0.95 V) and different temperatures (333 to 363 K) in BMIMBF 4 containing 0.20 mol L-1 Co(BF4)z. The deposits were characterized using scanning electron microscope (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). SEM images show that a uniform, dense, and compact deposit was obtained at -0.80 V and 333 K. The deposits were identified as high-purity metallic Co for all experiments by EDS and XRD.IntroductionCobalt is known as a hard magnetic material and cobalt alloys have been shown to have excellent magnetic properties with adequate mechanical durability and corrosion resistance, which are needed for high performance magnetic recording applications [1-4]. The electrodeposition of Co alloy in the aqueous solution is generally difficult because of the narrow electrochemical potential window of water, which leads to the low current efficiency and worse quality of deposits due to the hydrogen embrittlement. Thus, aprotic ionic liquids (ILs) are expected to be the ideal alternative media for electrodeposition of cobalt or its alloy since ILs usually provide a wide working potential windows, negligible vapor pressure, and acceptable conductivity for electrolysis without the occurring of hydrogen evolution [5, 6]."

Jan 1, 2014