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Sample records for blast furnace granular

  1. BLAST FURNACE GRANULAR COAL INJECTION SYSTEM; FINAL

    International Nuclear Information System (INIS)

    Bethlehem Steel Corporation (BSC) requested financial assistance from the Department of Energy (DOE), for the design, construction and operation of a 2,800-ton-per-day blast furnace granulated coal injection (BFGCI) system for two existing iron-making blast furnaces. The blast furnaces are located at BSC's facilities in Burns Harbor, Indiana. The demonstration project proposal was selected by the DOE and awarded to Bethlehem in November 1990. The design of the project was completed in December 1993 and construction was completed in January 1995. The equipment startup period continued to November 1995 at which time the operating and testing program began. The blast furnace test program with different injected coals was completed in December 1998

  2. An update on blast furnace granular coal injection

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.G. [Bethlehem Steel Corp., Burns Harbor, IN (United States); Strayer, T.J.; Bouman, R.W. [Bethlehem Steel Corp., PA (United States)

    1997-12-31

    A blast furnace coal injection system has been constructed and is being used on the furnace at the Burns Harbor Division of Bethlehem Steel. The injection system was designed to deliver both granular (coarse) and pulverized (fine) coal. Construction was completed on schedule in early 1995. Coal injection rates on the two Burns Harbor furnaces were increased throughout 1995 and was over 200 lbs/ton on C furnace in September. The injection rate on C furnace reached 270 lbs/ton by mid-1996. A comparison of high volatile and low volatile coals as injectants shows that low volatile coal replaces more coke and results in a better blast furnace operation. The replacement ratio with low volatile coal is 0.96 lbs coke per pound of coal. A major conclusion of the work to date is that granular coal injection performs very well in large blast furnaces. Future testing will include a processed sub-bituminous coal, a high ash coal and a direct comparison of granular versus pulverized coal injection.

  3. Clean Coal III Project: Blast Furnace Granular Coal Injection Project Trail 1 Report - Blast Furnace Granular Coal Injection - Results with Low Volatile Coal

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-11-01

    This report describes the first coal trial test conducted with the Blast Furnace Granular Coal Injection System at Bethlehem Steel Corporation's Burns Harbor Plant. This demonstration project is divided into three phases: Phase I - Design Phase II - Construction Phase III - Operation The design phase was conducted in 1991-1993, Construction of the facility began in August 1993 and was completed in late 1994. The coal injection facility began operating in January 1995 and Phase III began in November 1995. The Trial 1 base test on C furnace was carried out in October 1996 as a comparison period for the analysis of the operation during subsequent coal trials.

  4. BLAST FURNACE GRANULAR COAL INJECTION SYSTEM. Final Report Volume 2: Project Performance and Economics

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    1999-10-01

    Bethlehem Steel Corporation (BSC) requested financial assistance from the Department of Energy (DOE), for the design, construction and operation of a 2,800-ton-per-day blast furnace granulated coal injection (BFGCI) system for two existing iron-making blast furnaces. The blast furnaces are located at BSC's facilities in Burns Harbor, Indiana. The demonstration project proposal was selected by the DOE and awarded to Bethlehem in November 1990. The design of the project was completed in December 1993 and construction was completed in January 1995. The equipment startup period continued to November 1995 at which time the operating and testing program began. The blast furnace test program with different injected coals was completed in December 1998.

  5. Understanding a blast furnace

    International Nuclear Information System (INIS)

    Studies of the drainage of molten iron and slag from a blast furnace have been carried out by ANSTO scientists by monitoring the passage of radioactive tracers through the furnace. Gold-198 and cobalt-60 are used to track the molten iron, and lanthanum-140 and scandium-46 are used to track the slag

  6. Alkaline carbonates in blast furnace process

    Directory of Open Access Journals (Sweden)

    P. Besta

    2014-10-01

    Full Text Available The production of iron in blast furnaces is a complex of physical, chemical and mechanical processes. The input raw materials contain not only metallic components, but also a number of negative elements. The most important negative elements include alkaline carbonates. They can significantly affect the course of the blast furnace process and thus the overall performance of the furnace. As a result of that, it is essential to accurately monitor the alkali content in the blast furnace raw materials. The article analyzes the alkali content in input and output raw materials and their impact on the blast furnace process.

  7. Blast furnace operation analysis by thermic exergy

    International Nuclear Information System (INIS)

    In order to know the blast furnace thermic state, the thermic exergy can be used, which considers the temperatures level of the process. The magnitude analysis of thermic exergy for blast furnace operation using pulverized coal, natural gas and oxygen injection by tuyeres, shows that natural gas injection is less effective than pulverized coal and enriched blast with oxygen simultaneous injection. (Author) 6 refs

  8. The use of blast furnace slag

    Directory of Open Access Journals (Sweden)

    V. Václavík

    2012-10-01

    Full Text Available The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  9. Physical degradation of coke in blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, Y.

    1985-01-01

    Studies on dissected blast furnaces have shown that significant coke degradation takes place at a position 3-5 m above the tuyere level. Laboratory tests and analysis of blast furnace operational data have been used to investigate the roles of thermal degradation, deterioration by CO/sub 2/ reaction, and mineral compound attack. The results are reported.

  10. The use of blast furnace slag

    OpenAIRE

    Václavík, Vojt?ch; Dirner, Vojtech; Dvorský, Tomáš; Daxner, J.

    2012-01-01

    The paper presents the results of experimental research that dealt with the substitution of fi nely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on fi nely ground blast furnace slag were observed.

  11. The use of blast furnace slag

    OpenAIRE

    Václavík, V.; V. Dirner; Dvorský, T.; Daxner, J.

    2012-01-01

    The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  12. Coals characterization for blast furnace tuyeres injection

    International Nuclear Information System (INIS)

    The efficiency of blast furnace operation with pulverized coal injection (PCI) by tuyeres is determined by the composition and properties of the used coals and by the quality of the ferrous burden and coke. A study in thermo balance of coals to be injected by tuyeres is carried out, and the softening and melting temperatures of coals ash are determined. The coal performance and its influence in the blast furnace operation is estimated. (Author) 7 refs

  13. Reduction disintegration mechanism of cold briquettes from blast furnace dust and sludge

    OpenAIRE

    Leandro Rocha Lemos; Saulo Henrique Freitas Seabra da Rocha; Luiz Fernando Andrade de Castro

    2015-01-01

    It is important to understand the reduction disintegration mechanism in ferriferous burden that is used in blast furnaces. The behavior of this burden in the granular zone of this metallurgical reactor is important for smooth operation. The objective of this work was to prepare cold self-reducing briquettes using blast furnace dust and sludge and binders and compare the reduction disintegration index (RDI) of these agglomerates with conventional ferriferous burdens such as pellets, sinter and...

  14. Pulverized coal injection (PCI) in a blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    This short paper summarises the development of pulverised coal injection and its performance in the blast furnace at Kobe Steel. Coal injection has been in use at two of the company's blast furnaces since Spring 1983.

  15. Blast furnace control after the year 2000

    Energy Technology Data Exchange (ETDEWEB)

    Gyllenram, R.; Wikstroem, J.O. [MEFOS, Luleaa (Sweden); Hallin, M. [SSAB Tunnplaat AB, Luleaa (Sweden)

    1996-12-31

    Rapid technical development together with developments in work organization makes it important to investigate possible ways to achieve a cost efficient process control of different metallurgical processes. This paper describes a research project, and proposes a human oriented Information Technology Strategy, ITS, for control of the Blast Furnace process. The method used is that of deductive reasoning from a description of the prevailing technological level and experiences from various development activities. The paper is based on experiences from the No. 2 Blast Furnace at Luleaa Works but the conclusions do not at this stage necessarily reflect the opinion of the management and personnel or reflect their intentions for system development at SSAB.

  16. Blast furnace operation with small size coke

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, T.

    1984-01-01

    Use of up to 100% small coke (mean size ca. 20 mm) in the Kobe No. 1 blast furnace proved possible but increased the fuel rate and reduced the productivity. The coke size at the tuyeres was close to that obtained when charging large coke.

  17. BLAST FURNACE CAST HOUSE EMISSION CONTROL TECHNOLOGY ASSESSMENT

    Science.gov (United States)

    The study describes the state-of-the-art of controlling fumes escaping from blast furnace cast houses. Background information is based on: a study of existing literature; visits to blast furnaces in the U.S., Japan, and Europe; meetings with an ad hoc group of experienced blast f...

  18. Oil injection into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Dongsheng Liao; Mannila, P.; Haerkki, J.

    1997-12-31

    Fuel injection techniques have been extensively used in the commercial blast furnaces, a number of publications concerning the fuels injection have been reported. This present report only summarizes the study achievements of oil injection due to the research need the of authors, it includes the following parts: First, the background and the reasons reducing coke rate of oil injection are analyzed. Reducing coke rate and decreasing the ironmaking costs are the main deriving forces, the contents of C, H and ash are direct reasons reducing coke rate. It was also found that oil injection had great effects on the state of blast furnace, it made operation stable, center gas flow develop fully, pressure drop increase, descent speed of burden materials decrease and generation of thermal stagnation phenomena, the quality of iron was improved. Based on these effects, as an ideal mean, oil injection was often used to adjust the state of blast furnace. Secondly, combustion behavior of oil in the raceway and tuyere are discussed. The distribution of gas content was greatly changed, the location of CO, H{sub 2} generation was near the tuyere; the temperature peak shifts from near the raceway boundary to the tuyere. Oxygen concentration and blast velocity were two important factors, it was found that increasing excess oxygen ratio 0.9 to 1.3, the combustion time of oil decreases 0.5 msec, an increase of the blast velocity results in increasing the flame length. In addition, the nozzle position and oil rate had large effects on the combustion of oil. Based on these results, the limit of oil injection is also discussed, soot formation is the main reason limiting to further increase oil injection rate, it was viewed that there were three types of soot which were generated under blast furnace operating conditions. The reason generating soot is the incomplete conversion of the fuel. Finally, three methods improving combustion of oil in the raceway are given: Improvement of oil atomization, increased blast temperature and oxygen and injection of reducing gases into the bosh zone. (orig.) 25 refs.

  19. Determination of leakage in blast furnaces cooling plates

    International Nuclear Information System (INIS)

    Blast furnace walls are cooled by the circulation of water through copper plates inserted into the blast furnace refractory lining. Plates are fed by circular pipelines, called distribution rings, installed at different levels of the reactor. Because of normal corrosion, plates wear away and can eventually perforate, allowing the leakage of cooling water inside the blast furnace. A system has been designed and installed in order to confirm the eventual occurrence of leakages in the cooling plates of a blast furnace refractory lining. The system injects a solution of tritium into the feeding pipeline and determines, by means of liquid scintillation counting, the concentration of tritium in the exhausting gases at the top of the blast furnace. The system was tested under different blast furnace operating conditions, and allowed the detection and determination of leakages greater than 0.5 1/min. Following necessary maintenance, the system also confirmed the satisfactory results of the corrective actions. (author). 48 refs., 13 figs., 29 tabs

  20. Reduction disintegration mechanism of cold briquettes from blast furnace dust and sludge

    Directory of Open Access Journals (Sweden)

    Leandro Rocha Lemos

    2015-07-01

    Full Text Available It is important to understand the reduction disintegration mechanism in ferriferous burden that is used in blast furnaces. The behavior of this burden in the granular zone of this metallurgical reactor is important for smooth operation. The objective of this work was to prepare cold self-reducing briquettes using blast furnace dust and sludge and binders and compare the reduction disintegration index (RDI of these agglomerates with conventional ferriferous burdens such as pellets, sinter and iron ore. In the present work, 25 different mixtures were prepared to produce briquettes in two geometries: pillow and cylindrical. The RDI value was determined for the briquettes that passed the tumbling test.

  1. Current situation and predictions further development of blast furnace technology

    Directory of Open Access Journals (Sweden)

    J. Mróz

    2012-12-01

    Full Text Available Purpose: of the paper is to present analysis on main technological factors that determine blast furnace worldwide productivity in today’s time and may probably influence it in the future.Design/methodology/approach: to gain the purpose of the paper is based on the literature review of the proceedings of newest congresses and conferences on iron making technology. The review embraces manifold technical and technological changes in the area of the manufacture of iron in blast furnaces in most important regions of worldwide iron production. The prospects for future possible developments of blast furnace technology is presented, too.Findings: of this analysis show that directions of development of blast furnace technologies is characterized by: an increase the overall productivity of blast furnaces, the increase in volume blast furnaces and extending the period for campaign work of blast furnaces, systematic improving the quality of blast furnace charge, controlling its distribution, the introduction of coal dust injection and modernization of the equipments. Moreover, some specific researches were carried out e.g. a new process granulation for the control of melting materials, hybrid bonding iron ore of inferior quality, decreasing CO2 emissions in the process of sintering iron.The Chinese iron industry is oriented on modification of uneconomical structure of the iron production, excessive energy consumption and heavy impact on global environment. Research limitations/implications: Simulation calculations show that the future lines of the development of blast furnace technology should take into account: a use lower temperatures of hot blast and high blast enrichment in oxygen. b. injection of various fuels taking into account their prices in various world regions, c. the effective use of top gas, d. the possibility of eliminating blast furnace stoves. Originality/value: of the paper consist in transfer of knowledge helpful to further lowering energy for iron production and reducing harmful impact for the natural environment.

  2. Liquid flow in the hearth of the blast furnace

    International Nuclear Information System (INIS)

    The hearth of a blast furnace is poorly known. Our approach to characterize the hearth involves classical methods of chemical engineering, assessing the flow conditions by means of radioactive tracer techniques. The most important feature of this study is to combine measurements on industrial blast furnaces, experiments on a small scale model and flow model. calculations. 8 refs., 16 figs

  3. Thermal breakdown of coke in the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Filonenko, Yu.Ya.; Sharipov, V.N.; Kurbatov, A.V.

    1976-01-01

    The thermal stressing mechanism in coke during its use in the blast-furnace process is described, with reference to the temperature changes at the surface and center of coke lumps of various sizes as they travel down a 2000 m/sup 3/ blast furnace, and the associated thermal breakdown conditions. An equation is derived for thermal stresses in reheated coke.

  4. Durability of Alkali Activated Blast Furnace Slag

    Science.gov (United States)

    Ellis, K.; Alharbi, N.; Matheu, P. S.; Varela, B.; Hailstone, R.

    2015-11-01

    The alkali activation of blast furnace slag has the potential to reduce the environmental impact of cementitious materials and to be applied in geographic zones where weather is a factor that negatively affects performance of materials based on Ordinary Portland Cement. The scientific literature provides many examples of alkali activated slag with high compressive strengths; however research into the durability and resistance to aggressive environments is still necessary for applications in harsh weather conditions. In this study two design mixes of blast furnace slag with mine tailings were activated with a potassium based solution. The design mixes were characterized by scanning electron microscopy, BET analysis and compressive strength testing. Freeze-thaw testing up to 100 freeze-thaw cycles was performed in 10% road salt solution. Our findings included compressive strength of up to 100 MPa after 28 days of curing and 120 MPa after freeze-thaw testing. The relationship between pore size, compressive strength, and compressive strength after freeze-thaw was explored.

  5. Amorphous and crystalline blast furnace slag

    International Nuclear Information System (INIS)

    Full text: One of the by-products of iron production from a blast furnace is the slag, Generally 250-300 kg of slag is produced per ton of iron. Liquid blast furnace slag can either be cooled quickly by quenching in a granulator or more slowly in air. The air-cooled product is crushed and sized for use as an aggregate in concrete. The granulated slag is ground to form ground granulated slag, which is a cost-effective supplementary cementitious material. Blends of ground granulated slag and Portland cement produce a cementitious paste that is more resistant to chloride penetration than pastes made from the Portland cement alone. In this study neutron diffraction techniques were used to examine samples of air-cooled and granulated slags from Australian Steel Mill Services stock piles at Port Kembla. Sourced from the same blast furnace, the materials should be expected to posses similar elemental chemistry. The mineral compositions would be different due to the rate of cooling each slag was subjected to. Samples, 15 grams in mass, were mounted in a vanadium can and diffraction patterns were measured using the SLAD instrument on the Reactor R-2 at the Studvik Neutron Research Laboratory in Sweden. The diffraction patterns were transformed into radial distribution functions using the reverse Monte Carlo program, MCGR. The granulated slag showed no diffraction peaks while the air cooled slag showed a crystalline product that can be identified by x-ray diffraction. The radial distribution functions showed differences that were consistent with the granulated slag being amorphous and the air-cooled slag crystalline. Both slag samples showed peaks in the radial distribution function at 1.8 Angstroms and 2.8 Angstroms. The greatest anomaly was a feature about 2.5 Angstroms found only in the radial distribution function for the granulated slag. This demonstration showed that there are differences in the short range bonding between the two compounds. We are currently determining the chemical significance of this information and its relation to the differing cementitious properties of the two compounds. This analytical technique is now being investigated on data generated at the HIFAR reactor

  6. Natural radioactivity in blast furnace slag

    International Nuclear Information System (INIS)

    The paper is part of a series of systematic investigations on natural radioactivity in iron and steel raw materials in finite products. The blast furnace slag is an iron and steel by-product most useful in industry. The analyses of slag samples from each batch over three months reveled the presence of the natural series 232 Th and 238 U. For detection we used a high resolution gamma spectrometry system with built-in computer in Marinelli geometry. The specific activities of the following descendants were given: 212 Pb, 208 Tl, 228 Ac, 214 Pb, and 214 Bi. Natural radioactivity was found to be lower in slag than in iron and steel raw materials. (Author)

  7. Deposition of cesium and cobalt sorbed on zeolite in matrices of blast furnace slag

    International Nuclear Information System (INIS)

    137Cs and 60Co were sorbed from model solutions and waste water on chemically treated granular zeolite. The zeolite was incorporated into cement slurries based on blast furnace slag (BFS). The compressive and bending strength were measured after different times of hydration. The leaching tests were performed in water, base and acid solutions. The leachability was more pronounced only for samples in acidic solutions. (author). 15 refs., 3 figs., 4 tabs

  8. Determination of leakages in blast furnace cooling plates

    International Nuclear Information System (INIS)

    A system has been designed and installed in order to confirm the eventual occurrence of leakages in the cooling plates of a blast furnace refractory lining. The system injects a solution of T into the feeding pipeline and determines, by means of liquid scintillation (LS) counting, the concentration of T in the exhausting gases at the top of the blast furnace. The system was tested under different blast furnace operating conditions, and allowed the detection and determination of leakages greater than 0.5 L/min. Following necessary maintenance, the system also confirmed the satisfactory results of the corrective actions. (author)

  9. Mercury in dumped blast furnace sludge

    Science.gov (United States)

    Földi, Corinna

    2014-05-01

    Blast furnace sludge (BFS) is a waste generated in the production of pig iron and was dumped in sedimentation ponds. As these wastes often contain high contents of zinc, lead, cadmium, and arsenic, significant hazards to environmental surroundings may arise from former BFS sedimentation ponds. Sixty-five samples from seven BFS locations in Europe were investigated regarding the toxic element mercury (Hg) for the first time. The charge material of the blast furnace operations (coke, iron ores, and additives such as olivine, bauxite, ilmenite and gravels) revealed Hg contents from 0.015 to 0.093 mg kg-1. In comparison, the Hg content of BFS varied between 0.006 and 20.8 mg kg-1 with a median of 1.63 mg kg-1, which indicates enrichment with Hg. For one site with a larger sample set (n = 31), Hg showed a stronger correlation with the total non-calcareous carbon (C) including coke and graphite (r = 0.695; n = 31; p < 0.001). It can be assumed that these C-rich compounds are hosting phases for Hg. The solubility of Hg was rather low and did not exceed 0.43% of total Hg. The correlation between the total Hg concentration and total amount of NH4NO3-soluble Hg was relatively poor (r = 0.496; n = 27; p = 0.008) indicating varying hazard potentials of the different BFS. Consequently, BFS is a mercury-containing waste and dumped BFS should be regarded as potentially mercury-contaminated sites.

  10. A Study on Selected Hot-Metal and Slag Components for Improved Blast Furnace Control

    OpenAIRE

    Andersson, Annika

    2003-01-01

    The main objective of this work was to gain an increasedunderstanding of selected blast furnace phenomena which couldbe utilized for an improved blast furnace process control. Thisthesis contributes with both a model study and an experimentalstudy on blast furnace tapping, and results from these findingscan be used to enhance the control of the blast furnace. The work was divided in two parts. The first part dealt witha model study for optimisation of the blast furnace burdencalculation. Duri...

  11. The use of radioactive tracers in the blast furnace

    International Nuclear Information System (INIS)

    The efficiency of the blast furnace operation does not depend only on the properties of the materials but also on the conditions of contact between phases. Radioactive tracers have brought new information about the motion of gas, solids and liquids inside the furnace. The flow of materials through the furnace may be well described using a two zones model: the shaft is a counter current heat and mass exchanger with a plug flow behaviour; the dripping zone and the hearth behave like a mixed reactor. An original technique has been developed at IRSID using xenon capsules to measure the location of isotherms in the blast furnace. This technique has been applied to establish relations between the heat pattern and the operation of french blast furnaces. It has brought about a better understanding of the internal conditions of the furnace through the description of the various local thermal and chemical paths that may exist in central operating blast furnaces. The heterogeneous distribution of gas and solids on the furnace radius has been related with the efficiency of gas solid reactions in the shaft, with the aerodynamics of the furnace and with the thermal conditions at the walls

  12. Review and evaluation of alternative processes to the blast furnace

    International Nuclear Information System (INIS)

    A critical review on the alternative processes to the blast furnace, involving both solid and liquid state reduction is presented. Process comparison allows to identify advantages and disadvantages of each type of processes as well as to highlight the major challenges faced in order to compete with the traditional iron making route: the blast furnace, which today rules the production of iron units worldwide. (Author) 31 refs

  13. REACTIVATION OF GRANULAR CARBON IN AN INFRARED TRAVELING BELT FURNACE

    Science.gov (United States)

    An all-electrical Shirco carbon regeneration furnace and its air pollution control system have been evaluated for cost and process effectiveness in carbon reactivation at the Pomona Advanced Wastewater Treatment Research Facility. The granular activated carbon used for the Shirco...

  14. Operation of pulverized coal injection into large blast furnace with high top pressure

    Energy Technology Data Exchange (ETDEWEB)

    Wakuri, S.

    1984-01-01

    Nippon Steel Corporation began pulverised coal injection at No. 1 blast furnace at their Oita Works in June 1981. Since then, both the coal injection system and the blast furnace have operated without serious trouble. This report describes the development of techniques for pulverised coal injection to a large blast furnace with high top pressure and high blast temperature. The operational results of Oita No. 1 blast furnace are compared with those of oil injection and all-coke operations.

  15. A General Viscosity Model for Molten Blast Furnace Slag

    Science.gov (United States)

    Gan, Lei; Lai, Chaobin

    2014-06-01

    Blast furnace slag is the most abundant slag in the steel industry. Its metallurgical properties are determined to a great extent by its viscosity. Therefore, it is necessary to establish a reliable viscosity model for blast furnace slag. In the current work, a simple, accurate, and physically meaningful viscosity model for a wide composition range of blast furnace slags is developed based on the Vogel-Fulcher-Tammann (VFT) equation: log ? = A + B/( T - C). The model is calibrated by a database containing 365 compositions and 1233 measurements of synthetic and industrial slags. The parameter A has a value of -3.10. The parameters B and C are related to the mass fraction ratio of (CaO + MgO) to (SiO2 + Al2O3) and liquidus temperature of the slag, respectively. Present viscosity model accurately predicts the viscosity of blast furnace slag with relative average error (?) of 0.211 (±0.180) and root mean square error (RMSE) of 0.239 Pa·s. A slight modification of this model can also predict the glass transition temperature of blast furnace slag satisfactorily.

  16. Model for burden distribution tracking in the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Henrik Saxen; Jan Hinnela [Aabo Akademi University, Aabo (Finland). Faculty of Chemical Engineering

    2004-03-01

    A model of the distribution of burden layers in blast furnaces with bell-type charging equipment was developed on the basis of a radar measurement of the vertical level of the burden in one radial point. The measurement was utilized in combination with equations for the dump volume and the repose angle of the charged material. The parameters of two half-lines, which intersect in the point where the (calculated) trajectory of the charged material ends, were estimated by solving a least-squares fit problem. The performance of the model was first illustrated on artificial data, followed by a tuning and an application to process data from two distinct periods of operation of a Finnish blast furnace. It was demonstrated that the model was able to capture the general behavior of the charging process and that it could be used as a tool for tracking changes in the burden distribution in operating blast furnaces.

  17. Radiometric report for a blast furnace tracing with radioactive isotopes

    International Nuclear Information System (INIS)

    One of the methods to monitor refractory wall of blast furnace is its tracing with radioactive isotopes. The tracer isotope can be detected by two ways: the external dosimetric measurement at the armour of the blast furnace and/or the radiometric measurement of the iron sample charge by charge. Any change in radiometric situation of tracer radioisotope is recorded in a radiometric report. This paper presents an original concept of radiometric report based upon PARADOX and CORELDRAW soft kits. Their advantage are: quick and easy changes, easy recording of current radioactivity of tracer isotope, short history of changes, visual mapping of the tracer isotope and others. In this way we monitored 6 blast furnaces and more than 180 radioactive sources

  18. Nodal wear model: corrosion in carbon blast furnace hearths

    International Nuclear Information System (INIS)

    Criteria developed for the Nodal Wear Model (NWM) were applied to estimate the shape of the corrosion profiles that a blast furnace hearth may acquire during its campaign. Taking into account design of the hearth, the boundary conditions, the characteristics of the refractory materials used and the operation conditions of the blast furnace, simulation of wear profiles with central well, mushroom and elephant foot shape were accomplished. The foundations of the NWM are constructed considering that the corrosion of the refractory is a function of the temperature present at each point (node) of the liquid metal-refractory interface and the corresponding physical and chemical characteristics of the corrosive fluid. (Author) 31 refs

  19. Optimization of an Automatic Blast Furnace through Integrated Simulation Modeling

    Directory of Open Access Journals (Sweden)

    Ali Azadeh

    2006-01-01

    Full Text Available The objective of this study was to develop an integrated simulation model of an automatic blast furnace in a full-scale steelmaking factory. The integrated simulation model introduces a set of optimizing alternatives through sensitivity analysis. The simulation model is built by considering all major and detailed operations and interacting systems of the blast furnace workshop. The workshop is composed two parallel blast furnace each containing of a joint raw material storage and furnace and cast-iron stations. Furthermore, there are 54 operations for each blast furnace workshop. The results and the structure of the integrated simulation model were verified and validated by comparative analysis and t-test. Moreover, the monthly production rate of cast-iron station is chosen as the performance measure for the actual system and simulation model in a twelve months trial. The results of t-test shows the average monthly production of cast-iron for the two system is statistically equal (at ?=0.05. Also, the industrial engineering unit and the production managers accredited the integrated model. After this stage, the simulation was run for a period of six months to evaluate major bottlenecks in the system. Finally, two optimizing alternatives, which can save the company millions of Dollars, are introduced and their economic advantages are discussed. The integrated simulation model has several unique features. First, it is integrated and considers all operations, maintenance, repairs, quality control activities, systems' limitations and interaction with other systems. Second, it is coded in parametric fashion so any alternative may be easily retrieved. Third, it is a practical tool due to its verification, validation and accreditation. Finally, a standard procedure for development of integrated simulation model for similar blast furnace or workshops is introduced.

  20. Numerical Study of the Reduction Process in an Oxygen Blast Furnace

    Science.gov (United States)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2016-02-01

    Based on computational fluid dynamics, chemical reaction kinetics, principles of transfer in metallurgy, and other principles, a multi-fluid model for a traditional blast furnace was established. The furnace conditions were simulated with this multi-fluid mathematical model, and the model was verified with the comparison of calculation and measurement. Then a multi-fluid model for an oxygen blast furnace in the gasifier-full oxygen blast furnace process was established based on this traditional blast furnace model. With the established multi-fluid model for an oxygen blast furnace, the basic characteristics of iron ore reduction process in the oxygen blast furnace were summarized, including the changing process of the iron ore reduction degree and the compositions of the burden, etc. The study found that compared to the traditional blast furnace, the magnetite reserve zone in the furnace shaft under oxygen blast furnace condition was significantly reduced, which is conducive to the efficient operation of blast furnace. In order to optimize the oxygen blast furnace design and operating parameters, the iron ore reduction process in the oxygen blast furnace was researched under different shaft tuyere positions, different recycling gas temperatures, and different allocation ratios of recycling gas between the hearth tuyere and the shaft tuyere. The results indicate that these three factors all have a substantial impact on the ore reduction process in the oxygen blast furnace. Moderate shaft tuyere position, high recycling gas temperature, and high recycling gas allocation ratio between hearth and shaft could significantly promote the reduction of iron ore, reduce the scope of the magnetite reserve zone, and improve the performance of oxygen blast furnace. Based on the above findings, the recommendations for improvement of the oxygen blast furnace design and operation were proposed.

  1. Numerical Study of the Reduction Process in an Oxygen Blast Furnace

    Science.gov (United States)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2015-10-01

    Based on computational fluid dynamics, chemical reaction kinetics, principles of transfer in metallurgy, and other principles, a multi-fluid model for a traditional blast furnace was established. The furnace conditions were simulated with this multi-fluid mathematical model, and the model was verified with the comparison of calculation and measurement. Then a multi-fluid model for an oxygen blast furnace in the gasifier-full oxygen blast furnace process was established based on this traditional blast furnace model. With the established multi-fluid model for an oxygen blast furnace, the basic characteristics of iron ore reduction process in the oxygen blast furnace were summarized, including the changing process of the iron ore reduction degree and the compositions of the burden, etc. The study found that compared to the traditional blast furnace, the magnetite reserve zone in the furnace shaft under oxygen blast furnace condition was significantly reduced, which is conducive to the efficient operation of blast furnace. In order to optimize the oxygen blast furnace design and operating parameters, the iron ore reduction process in the oxygen blast furnace was researched under different shaft tuyere positions, different recycling gas temperatures, and different allocation ratios of recycling gas between the hearth tuyere and the shaft tuyere. The results indicate that these three factors all have a substantial impact on the ore reduction process in the oxygen blast furnace. Moderate shaft tuyere position, high recycling gas temperature, and high recycling gas allocation ratio between hearth and shaft could significantly promote the reduction of iron ore, reduce the scope of the magnetite reserve zone, and improve the performance of oxygen blast furnace. Based on the above findings, the recommendations for improvement of the oxygen blast furnace design and operation were proposed.

  2. Studying and improving blast furnace cast iron quality

    OpenAIRE

    ?. ?. Balgabekov; D. K. Issin; Kimanov, B. M.; Issagulov, A. Z.; Zholdubayeva, Zh. D.; ?. Z. Akashev; B. D. Issin

    2014-01-01

    In the article there are presented the results of studies to improve the quality of blast furnace cast iron. It was established that using fire clay suspension for increasing the mould covering heat conductivity improves significantly pig iron salable condition and filtration refining method decreases iron contamination by nonmetallic inclusions by 50 – 70 %.

  3. Production of blast furnace coke and utilization of binder

    Energy Technology Data Exchange (ETDEWEB)

    Sunami, Y.

    1981-01-01

    This article considers the production of blast furnace coke from non-caking or poorly-caking coals. It describes coke oven operation, coke manufacture, the kinetics of coking, the role of the binder, and the potential of petroleum pitch as a binder. (5 refs.) (In Japanese)

  4. CYANIDE REMOVAL FROM COKE MAKING AND BLAST FURNACE WASTE WATERS

    Science.gov (United States)

    The report gives results of a study to determine the feasibility of removing cyanide from coke making and blast furnace waste waters by ion flotation or column precipitate flotation of iron ferrocyanides. Ion flotation was reasonably effective on ferricyanide, but not on cyanide ...

  5. Reduction of costs of iron production by changing parameters of the mixed blast-furnace wind

    OpenAIRE

    Terpák, J.; Dorčák, L'.; Koštial, I.; L. Pivka

    2010-01-01

    The blast-furnace wind from hot-blast stoves is a significant factor of the blast furnace functioning. The technology was analyzed in which the hot wind from hot-blast stoves is not mixed with the cool wind to a constant wind temperature, but is blown directly into the blast furnace. However, it is necessary to compensate for the changes of the theoretical temperature of burning in blast furnace as a consequence of non-stabilized wind temperature, by changing composition of the wind. This can...

  6. Forecast situation of the blast furnace cohesive zone

    International Nuclear Information System (INIS)

    A series of sinters are manufactured in the pilot plant, using a mineral mixture, like that blast furnace. The sinters are characterised, by chemical and granulometric analysis and by determining the softening and melting temperatures. In the blast furnace temperatures are determined by using a series of probes in the furnace which make it possible to locate the position of the isotherm of higher temperature of 950 degree centigrade, which correspond to the reserve thermic zone. A model has been developed, proposing and indirect estimation of the shape of the cohesive zone through the determination of the isotherm with the highest temperature in the thermic reserve zone. The values of the softening and melting temperatures of sinters can be used to estimate the isotherms limiting the cohesive zone in the 1300-1400 degree centigrade range. (Author)

  7. Discrete blasts in granular material yield two-stage process of cavitation and granular fountaining

    Science.gov (United States)

    Andrews, Robin; White, James; Dürig, Tobi; Zimanowski, Bernd

    2014-05-01

    A discrete blast within granular material, such as a single subterranean explosion within a debris-filled diatreme structure, is typically considered to produce a single uprush of material. Our experiments demonstrate that apparent "debris jet deposits" can be formed by a two-stage process of cavitation and subsequent granular fountaining. Bench-scale experiments reported here demonstrate that for a range of overpressures and depths, individual, discrete, buried gas blasts open space and expel particles from the blast site in two largely decoupled stages. Expanding gas initially pierces material nearest the blast source to open a cavity above it; then a fountain of grains rises from the source into the cavity. This staged motion dynamically segregates source grains from host-material grains, and the rates of cavity opening vs. fountain rise show a power-law decay relationship with initial pressure. Our experimental analysis has implications for maar-diatreme systems, field-scale detonation experiments, and underground nuclear testing.

  8. Torrefied biomasses in a drop tube furnace to evaluate their utility in blast furnaces.

    Science.gov (United States)

    Chen, Wei-Hsin; Du, Shan-Wen; Tsai, Chien-Hsiung; Wang, Zhen-Yu

    2012-05-01

    Torrefaction and burning characteristics of bamboo, oil palm, rice husk, bagasse, and Madagascar almond were studied and compared with a high-volatile bituminous coal using a drop tube furnace to evaluate the potential of biomass consumed in blast furnaces. Torrefaction at 250 and 300°C for 1h duration was carried out. Analysis using the ash tracer method indicated that the extent of atomic carbon reduction in the biomasses was less than that of atomic hydrogen and oxygen. Torrefaction also lowered the sulfur content in bamboo and oil palm over 33%. An examination of the R-factor and burnout of the samples suggests that more volatiles were released and a higher burnout was achieved with raw and torrefied biomasses at 250°C than at 300°C; however, torrefaction at 300°C is a feasible operating condition to transform biomass into a solid fuel resembling a high-volatile bituminous coal used for blast furnaces. PMID:22386202

  9. Some aspects of deterioration of coke in blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, H.

    1985-01-01

    Studies have been carried out of the degradation of coke in a large blast furnace. The results show: (1) that degradation is greatly influenced by the temperature at which the coke is subjected to the CO/sub 2/ reaction; (2) lump coke does not change in size up to 1400 C but begins to reduce in size markedly above 1400 C; (3) coke fines deposited between the lower part of the shaft and the tuyeres are concentrated in the vicinity of the raceway; (4) increasing the alkali content of the coke (by 5% maximum in this study) does not decrease coke strength. The results suggest that the size reduction ratio of coke is higher and the degradation conditions for coke become more severe in large blast furnaces than in small ones.

  10. Mathematical-statistical forecast of blast furnace coke quality

    Energy Technology Data Exchange (ETDEWEB)

    Filonenko, Yu.Ya.; Konev, N.L.; Parakhin, A.V. (Lipetskii Politekhnicheskii Institut (USSR))

    1991-01-01

    Evaluates a method developed in the USSR for forecasting blast furnace coke quality on the basis of mathematical modeling and statistical data that characterize the quality of blast furnace coke in the leading coking plants of the USSR. The models consider effects of the following factors on coke quality: mean reflectivity of coal mixtures used for coking, content of leaning components, caking power of coal mixtures, a relation of coke oven width and coking time. The method is used for forecasting the coke compression strength index, abrasion index and grain size distribution. Forecasting accuracy is evaluated using data on coke quality supplied by forecasting and actual data characterizing quality of coke from the main plants in the USSR. 3 refs.

  11. Thermal Spray Coatings for Blast Furnace Tuyere Application

    Science.gov (United States)

    Pathak, A.; Sivakumar, G.; Prusty, D.; Shalini, J.; Dutta, M.; Joshi, S. V.

    2015-12-01

    The components in an integrated steel plant are invariably exposed to harsh working environments involving exposure to high temperatures, corrosive gases, and erosion/wear conditions. One such critical component in the blast furnace is the tuyere, which is prone to thermal damage by splashing of molten metal/slag, erosive damage by falling burden material, and corrosion from the ensuing gases. All the above, collectively or independently, accelerate tuyere failure, which presents a potential explosion hazard in a blast furnace. Recently, thermal spray coatings have emerged as an effective solution to mitigate such severe operational challenges. In the present work, five different coatings deposited using detonation spray and air plasma spray techniques were comprehensively characterized. Performance evaluation involving thermal cycling, hot corrosion, and erosion tests was also carried out. Based on the studies, a coating system was suggested for possible tuyere applications and found to yield substantial improvement in service life during actual field trials.

  12. Reduction of costs of iron production by changing parameters of the mixed blast-furnace wind

    Directory of Open Access Journals (Sweden)

    J. Terpák

    2010-04-01

    Full Text Available The blast-furnace wind from hot-blast stoves is a significant factor of the blast furnace functioning. The technology was analyzed in which the hot wind from hot-blast stoves is not mixed with the cool wind to a constant wind temperature, but is blown directly into the blast furnace. However, it is necessary to compensate for the changes of the theoretical temperature of burning in blast furnace as a consequence of non-stabilized wind temperature, by changing composition of the wind. This can be done by adding different media into the wind with different results from the operational and economical viewpoints. Essentially, the following types of media are used in blast furnaces: steam, oxygen, substitution fuels, nitrogen, and waste gas.

  13. The effect of blast furnace coke quality on the possibility of its use

    Directory of Open Access Journals (Sweden)

    A. Konstanciak

    2013-04-01

    Full Text Available In the paper behavior of the blast-furnace coke in the high temperature was presented. Comparative analysis of the chemical composition of the blast-furnace coke and the heat treatment of it were done. Coefficients M10 and M40 with the thermo-abrasiveness for chosen cokes were compared. The influence of ash content of the coke on the blast-furnace bed permeability was defined. Usefulness of the coke to blast-furnace process was also defined.

  14. Modelling of turbulent combustion in the blast furnace raceway

    Energy Technology Data Exchange (ETDEWEB)

    Karvinen, R.; Maekiranta, R. [Tampere Univ. (Finland). Energy and Process Engineering

    1996-12-31

    The phenomena concerning coke-gas -suspension and simultaneous combustion of solid coke particles and residual fuel oil in a blast furnace raceway are modelled. The flow field of suspension is predicted by using the two fluid model, which is based on the Eulerian method, in the Phoenics code. The standard k-e -model of turbulence is used. Pyrolysis of oil droplets is calculated with the own coded subroutine, which is based on the Lagrangian approach. Gas phase reaction rate is assumed to be controlled by chemical kinetics. Radiative heat transfer is calculated by using the six-flux method. Heterogenous surface reactions are used for the coke particles. Calculations without coke combustion show that due to a poor mixing in the hot blast, pyrolysis gases of residual fuel oil have not time enough to react with oxygen. It is obvious that if combustion of coke particles is taken into account, the oxygen content in the blast decreases to such a level, that unburnt pyrolysis gases can flow out of the raceway causing problems. The distribution of coke void fraction has been succeeded to predict in the raceway domain. Coke particles fall from the upper part of the raceway to the hot blast forming locally high concentrations, which affect very strongly the oxygen distribution of the hot blast. (orig.) SULA 2 Research Programme; 10 refs.

  15. Plasma torches at blast furnace: Four years of industrial experience in France

    Science.gov (United States)

    Delassatdepressigny, Y.; Drelon, R.; Butel, A.; Labrot, M.; Pineau, D.

    The industrial development of plasma systems at blast furnace in France is adressed. The aims of plasma utilization are outlined. An increase of blast temperature is usually limited to about 1250 C by the technology of hot blast stoves and plasma torches open a possibility of overpassing this limit. High coke rates required for ferromanganese production and the introduction of electricity to save coke are discussed. Experiences of plasma in the blast furnace, leading towards greater energy and production flexibility, are described. Plasma systems may now be considered as proven industrial technology for blast furnace and electricity a usable energy for primary metal production.

  16. Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Chenn Zhou

    2012-08-15

    The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has been developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.

  17. Experimental study on an oxygen blast furnace process using a blast furnace test plant. Kogata shiken koro ni yoru sanso koro ho no kento

    Energy Technology Data Exchange (ETDEWEB)

    Yamaoka, H. (Sumitomo Metal Industries Ltd., Osaka (Japan)); Kamei, Y. (The Japan Iron and Steel Federation, Tokyo (Japan))

    1991-12-01

    In the preceding report, a theoretical study was made on the oxygen blowing into the blast furnace and its effective utilization method using one dimensional blast furnace mathematical models. Although a combined injection of steam, ore and fuel such as pulverized coal is considered as a method to prevent the excessive rise of the flame temperature caused by the high oxygen concentration blast, it was indicated that when a combined injection of pulverized coal was used to prevent the excessive rise of the flame temperature, it would have a possibility to control the increase of the fuel rate as a consequence of the acceleration of the gas reduction. Successively in this report, the operation of the blast furnace test plant was conducted to confirm whether the oxygen blast furnace process can fulfil its actual functions as a practical iron-making process or not. As a result, it was demonstrated with the blast furnace test plant that the pulverized coal could be used without any problem at 1.2 Kg/Nm {sup 3} of the pulverized coal to oxygen ratio and eventually, a pulverized coal rate of 407 Kg/t, a coke rate of 258 Kg/t and a productivity of 7.35 t/dm {sup 3} were achieved. For this reason, the achievable extent of the large blast furnace could be estimated. 14 refs., 13 figs., 4 tabs.

  18. Acid slag injection into the blast furnace tuyere zone

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J.; Tervola, K. [Oulu Univ. (Finland). Dept. of Process Engineering

    1996-12-31

    The possibility of acid slag injection and its effect on the slag formation and on the melting behaviour of the charge materials are studied in the present work. The work is partly based on the literature evaluating the slag formation, slag properties and the basic slag injection. The possibility of acid slag injection is first examined by studying changes in the composition of the primary slag if the share of the acid slag component (Kostamus pellet/RR) of the charge material is lowered. Phase diagrams and viscosity charts are used to evaluate the viscosity, and solidus/liquidus temperature in the slag phase. The share of the slag phase of the pellet is evaluated by calculating the amount of the acid slag injection. The injection rate of some injectants is also examined. The primary slag formed of the sinter and the coke ash is in liquid form and its viscosity is close to the viscosity of the blast furnace slag. It is possible that the liquid slag phase can be formed in the blast furnace without the presence of the acid pellet because the melting point and the viscosity of the slag is lowered by alkalies, sulfur and the dissolved ironoxide of the slag. If high SiO{sub 2} content materials alone are used for injection there is a risk that the slag phase of the tuyere zone becomes too viscous. Olivine and some iron containing components such as fayalite are possible injection material. More information is needed to evaluate the effect of acid slag injection on the operation of the blast furnace. (orig.) SULA 2 Research Programme; 2 refs.

  19. Injection of heavy fuel oil into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Paloposki, T. [Helsinki Univ. of Technology, Otaniemi (Finland); Hakala, J.; Mannila, P.; Laukkanen, J. [Oulu Univ. (Finland)

    1996-12-31

    This study deals with the injection and combustion of heavy fuel oil in blast furnaces. The injection of the oil was studied experimentally in a small-scale test rig. The combustion of the oil was analysed with a commercial computer program for flow and combustion simulations. Results from computer simulations show that the combustion of the oil can be improved by decreasing the size of the oil drops and by enhancing the mixing between the oil drops and the hot blast. The devolatilization rate of the oil mainly depends on the size of the oil drops. The combustion rate of the volatiles mainly depends on the effectiveness of turbulent mixing with combustion air. Methods to decrease the size of the oil drops were sought in the experimental part of the study. Experimental results show that the size of the oil drops increases with increasing mass flow rate of the oil and decreases with increasing velocity of the hot blast. Methods to improve the mixing between the oil drops and the hot blast are suggested but have not yet been experimentally tested. (author) (4 refs.)

  20. Continuous measurement of blast-furnace coke moisture

    International Nuclear Information System (INIS)

    After presenting the advantages of applying neutron moisture gages to the continuous measurement of blast-furnace coke moisture and explaining the factors influencing the measurement accuracy, the necessity of calibrating these devices under flow conditions and the encountered difficulties are discussed. Using statistical methods it has been observed that the main source of calibration errors is the sampling phase. Based on results of mathematical processing, a new calibration method with higher performance - compared with the earlier ones - is proposed. This method allows to achieve high accuracy in a relatively short time. (author)

  1. Investigations concerning the wear of a blast-furnace lining by the isotopic tracer method

    International Nuclear Information System (INIS)

    The causes of the wear of a blast-furnace lining are described. The examination of the lining wear by the isotopic tracer method is presented. The results of measurements of the wear carried out of the lining of live blast furnaces from 500 to 900 m3 capacity are discussed. (author)

  2. BLAST FURNACE SLIPS AND ACCOMPANYING EMISSIONS AS AN AIR POLLUTION SOURCE

    Science.gov (United States)

    The report gives results of a study to ascertain the severity of blast-furnace slips and their accompanying bleeder-valve emissions as a source of air pollution. It describes factors contributing to the occurrence of hangs and slips in the blast furnace. It discusses the mechanic...

  3. DESTRUCTION AND REMOVAL OF POHCS (PRINCPAL ORGANIC HAZARDOUS CONSTITUENTS) IN IRON MAKING BLAST FURNACES

    Science.gov (United States)

    At least one steel company utilizes organic waste liquids as a heat and carbon content source to partially replace the coke that is used to charge the blast furnaces. The waste liquids fed to the blast furnace are likely to contain hazardous constituents. Temperature and residenc...

  4. Methods for monitoring heat flow intensity in the blast furnace wall

    OpenAIRE

    Dorčák, L'.; Terpák, J.; I. Podlubný; L. Pivka

    2010-01-01

    In this paper we present the main features of an online system for real-time monitoring of the bottom part of the blast furnace. Firstly, monitoring concerns the furnace walls and furnace bottom temperatures measurement and their visualization. Secondly, monitored are the heat flows of the furnace walls and furnace bottom. In the case of two measured temperatures, the heat flow is calculated using multi-layer implicit difference scheme and in the case of only one measured temperature, the hea...

  5. X-ray diffractometry of steam cured ordinary Portland and blast-furnace-slag cements

    International Nuclear Information System (INIS)

    This work studies some aspects of the phases produced by hydration of ordinary and blast-furnace-slag cements, at normal conditions and steam cured (60 and 950 C), using an X-ray diffraction technique. The blast-furnace-slag cement was a mixture of 50% of ordinary Portland cement and 50% of blast-furnace-slag (separately grinding). After curing the X-ray diffraction reveals that, in relation to ordinary Portland cement, the main phases in blast-furnace-slag cement are hydrated silicates and aluminates, hydro garnet, etringitte and mono sulphate. After steam curing the hydration of blast-furnace-slag cement proceeds. This is a result of the slag activation by the curing temperature. (author). 8 refs., 3 figs., 1 tab

  6. Preparation of Ceramic-Bonded Carbon Block for Blast Furnace

    Science.gov (United States)

    Li, Yiwei; Li, Yawei; Sang, Shaobai; Chen, Xilai; Zhao, Lei; Li, Yuanbing; Li, Shujing

    2014-01-01

    Traditional carbon blocks for blast furnaces are mainly produced with electrically calcined anthracite owing to its good hot metal corrosion resistance. However, this kind of material shows low thermal conductivity and does not meet the demands for cooling of the hearth and the bottom of blast furnaces. In this article, a new kind of a high-performance carbon block has been prepared via ceramic-bonded carbon (CBC) technology in a coke bed at 1673 K (1400 °C) using artificial graphite aggregate, alumina, metallic aluminum, and silicon powders as starting materials. The results showed that artificial graphite aggregates were strongly bonded by the three-dimensional network of ceramic phases in carbon blocks. In this case, the good resistance of the CBC blocks against erosion/corrosion by the hot metal is provided by the ceramic matrix and the high thermal conductivity by the graphite aggregates. The microstructure of this carbon block resembles that of CBC composites with a mean pore size of less than 0.1 ?m, and up to 90 pct of the porosity shows a pore size <1 ?m. Its thermal conductivity is higher than 30 W · m-1 · K-1 [293 K (20 °C)]. Meanwhile, its hot metal corrosion resistance is better than that of traditional carbon blocks.

  7. Coal blending models for optimum cokemaking and blast furnace operation

    Energy Technology Data Exchange (ETDEWEB)

    Vasko, F.J.; Newhart, D.D.; Strauss, A.D. [ISG Research, Bethlehem, PA (US)

    2005-03-01

    An important problem at an integrated steel-producing plant is the blending of different types of coals to make coke for the blast furnace operation. Historically, linear blending models were not appropriate because coal properties important for both optimum cokemaking and blast furnace operation do not combine linearly and are not completely understood. In this paper, a solution methodology is developed that utilizes two techniques: (1) a mixed integer linear programming model for blending the candidate coals to produce coke at a minimum cost and (2) binary decision tree analyses and results that are converted into model constraints to ensure the production of high-quality coke. Subsequently, the model results are used at the pilot-scale oven for testing and for validating the new, improved blend(s) that have been recommended by the model. This is an on-going need that is dictated by changing availabilities in both coal prices and sources. These steps reduce costs by both minimizing the number of blends to be tested at the pilot-scale facility and ensuring a minimum cost coal blend that is useable for the operating facilities. Hypothetical, but realistic, data are used to illustrate how the model performs.

  8. Some experience with radioisotopes in the study of the wear of blast furnace linings

    International Nuclear Information System (INIS)

    Cobalt-60 sources encapsulated in stainless steel are installed in the refractory lining of five out of the six blast furnaces of the Tata Iron and Steel Company, Jamshedpur. The wear of furnace lining has been monitored by monitoring the installed radioactive sources. The experience gained in 4-5 years of blast furnace compaign after the installation of cobalt-60 capsules is described. (M.G.B.)

  9. Simulation for the powder movement and accumulation in the lower part of blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, Takashi [Mineral Resources Research Center, Nippon Steel Technoresearch, Futtsu-shi Chiba (Japan)

    1997-12-31

    The behavior of unburnt char and coke powder in the blast furnace becomes material for discussion with the increase in injection rate of pulverized coal into the blast furnace. An analysis was made as to the simulation of powder accumulation at the deadman and dripping zone of blast furnace by using a powder/gas two-phases flow experimental data. When an excessive powder has penetrated at a low gas velocity, it brings an increment in holdup and the controlling factors are powder/gas ratio and gas velocity. An empirical formula used for estimating the powder hold-up in the blast furnace internal conditions has proposed based on similarity. The controlling {pi} numbers are Floude number, powder/gas ratio and particle diameter ratio of powder/lump. This empirical formular was connected with Blast Furnace Total Model `BRIGHT` for the simulation of powder amount distribution in the lower part of blast furnace. When Powder diameter Dk exceeds 100 {mu} and gas velocity becomes lower than 0.7m/s at PC1OOkg/T, the powder tends to accumulate in the deadman. These results was available for the decision of optimum blast conditions and optimum powder diameter in the high amount of pulverized coal injection to the blast furnace. (author) 10 refs.

  10. Cold blast furnace syndrome: a new source of toxic inhalation by nitrogen oxides

    Science.gov (United States)

    Tague, I; Llewellin, P; Burton, K; Buchan, R; Yates, D

    2004-01-01

    Methods: Fourteen workers developed acute respiratory symptoms shortly after exposure to "air blast" from blast furnace tuyeres. These included chest tightness, dyspnoea, rigors, and diaphoresis. Chest radiographs showed pulmonary infiltrates, and lung function a restrictive abnormality. This report includes a description of clinical features of the affected workers and elucidation of the probable cause of the outbreak. Results: Clinical features and occupational hygiene measurements suggested the most likely cause was inhalation of nitrogen oxides at high pressure and temperature. While the task could not be eliminated, engineering controls were implemented to control the hazard. No further cases have occurred. Conclusions: "Cold blast furnace syndrome" represents a previously undescribed hazard of blast furnace work, probably due to inhalation of nitrogen oxides. It should be considered in the differential diagnosis of acute toxic inhalational injuries in blast furnace workers. PMID:15090669

  11. Probing the inner structure of blast furnace by cosmic-ray muon radiography

    International Nuclear Information System (INIS)

    The visualization of the inner state of a blast furnace was investigated by exploiting the feature of cosmic-ray muon that attenuates according to the density and the thickness of the object through which it penetrates. The distribution of the cosmic-ray muon accumulated in an object in a blast furnace during a certain period has been determined by a probing system provided with two sets of a pair of panels with plastic scintillation counters segmented in parallel along each direction of both sides. First, measurement was performed in the furnace hearth structure that had been taken out after the shutdown of Oita No.2 Blast Furnace repaired in 2004. Next, another measurement was performed in the same manner in the renewed furnace hearth of Oita No.2 Blast Furnace which had just started working after its repairs. The density of the material at the iron-rich portion inside the hearth was estimated from the accumulation ratio obtained from the relation between the intensity of the muon channel passing through the iron-rich part in the hearth and that passing through its opposite channel symmetric to the coordinate origin. Then, the level of the furnace bottom brick, meaning its eroded thickness, was estimated from those accumulation ratios in relation to each crossing both the iron-rich part and the furnace bottom brick. The possibility of the density distribution of the material inside a blast furnace and the remaining thickness of bricks being estimated by this measurement method was identified. (author)

  12. Nuclear techniques for the inspection of blast furnaces

    International Nuclear Information System (INIS)

    Carbon hearth wall failures in blast furnaces create safety risks and require a large expense to repair. To avoid failures they are replaced early, incurring costs in wasted hearth wall use. Two non-invasive measurements provide realtime analysis of wall integrity. The two major failure modes are erosion of carbon thickness and iron-filled cracks in the bricks. Measurements of backscattered gamma-ray spectra and thermal neutron decay rate can identify both phenomena. Gamma-ray spectra from a compact Linac beam primarily respond to average carbon thickness. Neutron decay time, using a pulsed neutron source, is sensitive to iron in the carbon volume. Each measurement is sensitive to the other failure made, but the combination permits each phenomenon to be resolved. These techniques can detect a high atomic number and thermal neutron absorption cross section material behind one of low atomic number and thermal neutron absorption cross section

  13. Enriching blast furnace gas by removing carbon dioxide.

    Science.gov (United States)

    Zhang, Chongmin; Sun, Zhimin; Chen, Shuwen; Wang, Baohai

    2013-12-01

    Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent. PMID:25078829

  14. Immobilization of technetium in blast furnace slag grouts

    International Nuclear Information System (INIS)

    Blast furnace slags have been successfully used to reduce the leachability of technetium from cement-based waste forms, ostensible because the slag produces a less permeable product or reduces the pertechnetate to a less mobile form. Waste contaminated with technetium is of particular concern to the U.S. Nuclear Regulator Commission, Department of Energy, and Environmental Protection Agency because of its mobility as the pertechnetate ion. The technetium leachabilities of cement-based waste forms with and without a slag component and for different slags are presented. The mass transfer parameter (e.g., diffusivity) for leaching technetium from these waste forms decreased by five orders of magnitude when slag was used (i.e., using slag can increase the ANS 16.1 leachability index by five). Results of bulk and surface examinations of the slags are presented

  15. Characterization of the permeability of the blast furnace lower part

    International Nuclear Information System (INIS)

    In the context of high coal injection and high productivity operation, the coke behaviour inside the blast furnace hearth is the main parameter to control. Different and complementary investigations as radioactive and helium tracer injections, liquids and coke samplings, have been carried out at Sollac Fos BF1 using the tuyere probe to determine the hearth permeability and its evolutions as a function of the main control parameters, and to understand the hearth activity. The results of all these experiments give a very consistent picture of a heterogenous hearth with three concentric areas of various permeabilities to gas and liquids. A two concentric zones model has been built, which is in good agreement with the experimental results. It enables to evaluate the impact of the central zone on the liquids flow at the periphery. (author)

  16. Greener durable concretes through geopolymerisation of blast furnace slag

    Science.gov (United States)

    Rajamane, N. P.; Nataraja, M. C.; Jeyalakshmi, R.; Nithiyanantham, S.

    2015-05-01

    The eco-friendliness of concrete is quantified by parameters such as ‘embodied energy’ (EE) and ‘embodied CO2 emission’ (ECO2e), besides duration of designed ‘service life’. It may be noted that ECO2e is also referred as carbon footprint (CF) in the literature. Geopolymer (GP) is an inorganic polymeric gel, a type of amorphous alumino-silicate product, which can be synthesised by polycondensation reactions. The concrete reported in this paper was prepared using industrial wastes in the form of blast furnace slag, fly ash as geopolymeric source materials and sodium silicate and sodium hydroxide as activators. Many mechanical properties such as compressive strength, chloride diffusion, steel corrosion, rapid chloride permeability test and rapid migration test are compared with Portland cement.

  17. EFFECTS OF BLAST-FURNACE SLAG ON NATURAL POZZOLAN-BASED GEOPOLYMER CEMENT

    OpenAIRE

    MAHSHAD YAZDANIPOUR; EBRAHIM NAJAFI KANI; ALI ALLAHVERDI

    2011-01-01

    A number of geopolymer cement mixes were designed and produced by alkali-activation of a pumice-type natural pozzolan. Effects of blast-furnace slag on basic engineering properties of the mixes were studied. Different engineering properties of the mixes such as setting times and 28-day compressive strength were studied at different amounts of blast-furnace slag, sodium oxide content, and water-to-cement ratio. The mix comprising of 5 wt.% blast-furnace slag and 8 wt.% Na2O with a water-to-dry...

  18. Nodal wear model: corrosion in carbon blast furnace hearths

    Directory of Open Access Journals (Sweden)

    Verdeja, L. F.

    2003-06-01

    Full Text Available Criterions developed for the Nodal Wear Model (NWM were applied to estimate the shape of the corrosion profiles that a blast furnace hearth may acquire during its campaign. Taking into account design of the hearth, the boundary conditions, the characteristics of the refractory materials used and the operation conditions of the blast furnace, simulation of wear profiles with central well, mushroom and elephant foot shape were accomplished. The foundations of the NWM are constructed considering that the corrosion of the refractory is a function of the temperature present at each point (node of the liquid metal-refractory interface and the corresponding physical and chemical characteristics of the corrosive fluid.

    Se aplican los criterios del Modelo de Desgaste Nodal (MDN para la estimación de los perfiles de corrosión que podría ir adquiriendo el crisol de un homo alto durante su campaña. Atendiendo al propio diseño del crisol, a las condiciones límites de contorno, a las características del material refractario utilizado y a las condiciones de operación del horno, se consiguen simular perfiles de desgaste con "pozo central", con "forma de seta" ó de "pie de elefante". Los fundamentos del MDN se apoyan en la idea de considerar que la corrosión del refractario es función de la temperatura que el sistema pueda presentar en cada punto (nodo de la intercara refractario-fundido y de las correspondientes características físico-químicas del fluido corrosivo.

  19. Influence of Hot Metal Flow State to the Hearth Flow Field during Blast Furnace Tapping

    Directory of Open Access Journals (Sweden)

    Hong-Wei Guo

    2013-08-01

    Full Text Available Blast furnace tapping is one of the most important aspects of BF iron-making, a process during which the ideal state is for the molten iron to remain the invariant and the level of liquid to remain stable. However, due to the viscosity of molten iron, the liquid level will tilt to one side near the tap-hole, causing the iron flow field during blast furnace tapping to change with time. This research simulated two cases of horizontal and inclined molten iron liquid levels in the process of blast furnace tapping. This study also discusses different hearth erosion situations and explains the rationality of blast furnace large-scale trends from the perspective of molten iron liquid level stability.

  20. Development of pulverized coal injection system and its operation at blast furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, T.; Tamura, S.

    1984-01-01

    This brief paper is a synopsis of one presented to the 107th ISIJ Meeting in April 1984. It reports the development and successful operation of pulverised coal injection at two blast furnaces of Kobe Steel.

  1. PHYSICAL/CHEMICAL TREATMENT OF BLAST FURNACE WASTEWATERS USING MOBILE PILOT UNITS

    Science.gov (United States)

    The report documents an in-depth pilot-plant investigation of the applicability of advanced waste treatment methods for upgrading ironmaking blast furnace wastewaters to Best Available Technology Economically Achievable (BATEA) levels. Mobile treatments facilities, designed to op...

  2. Coal-oil mixture combustion program: injection into a blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Jansto, S.G.; Mertdogan, A.; Marlin, L.A.; Beaucaire, V.D.

    1982-04-30

    A chemically stabilized coal-oil mixture (COM) was made and used as an auxiliary fuel in a blast furnace for 44 days. Approximately 485,000 gallons of COM were produced at an on-site COM plant. Composition was 47.9% coal, 47.6% No. 6 oil, 4.0% water, and 0.5% emulsifier. Average injection rates were 3.8 to 13.0 gpm during different periods of the trial. Coal handling equipment, mixing and processing equipment, pumps, piping, fuel lances, and instrumentation are discussed. The blast furnace performance during the trial is compared to a Base Period of injecting No. 6 oil. Blast furnace performance was satisfactory, with one pound of COM replacing one pound of coke or 0.8 pound of No. 6 oil. The production of COM and its usage in a blast furnace is economical and feasible.

  3. Measurement of burden material level in blast furnace using radiometric level gage

    International Nuclear Information System (INIS)

    To increase reliability of recording circuit, to simplify adjustment and operation of radiometric level gauges for charge measuring in blast furnaces, a standart control unit on the base of semiconductors has been produced. It reduces radiation source activity by 6-7 times. The application of the control unit and the new modification of electromechanical driver makes it possible to increase considerably the life of radiometric level gauges of charge in blast furnaces

  4. The design of system for operative planning of blast furnace production process

    Directory of Open Access Journals (Sweden)

    Malind?ák Du?an

    1996-12-01

    Full Text Available A system for operative planning of blast furnace production process is described in the paper. The suggested system is based on the use of a new hierarchy of operative plans, consisting of one-month plan, (7+3 days plan, and 24-hour plan. The system allows smoothing of production process at the blast furnace plant, and at the same time satisfies all requirements of the steel plant regarding to the amount of pig iron.

  5. Determination of cadmium in blast furnace slag by multiple prompt gamma-ray analysis

    International Nuclear Information System (INIS)

    Since blast furnace slag is used widely (cement, concrete aggregate and so on), it is important to measure toxic heavy metal in slag. In this study, we measured Cd in blast furnace slag by Multiple Prompt Gamma-ray Analysis (MPGA) and investigated LLD (Lower Limit of Determination). As a result, LLD for Cd in slag was 1 ppm order (counting time: 3h). In each sample, Cd peak was not confirmed in this measurement. (author)

  6. Determination of burden descent rate in a blast furnace by a radioisotope technique

    International Nuclear Information System (INIS)

    The times and rates of burden descent in a blast furnace were studied using 46Sc radioisotope. The amounts and qualities of the radioactive material required for a full scale study were determined, and a suitable experimental procedure and evaluation method were developed.The data obtained by the present method make it possible to determine both the blast furnace capacity and the period that passed before the changes in burden and coke rates affect the process

  7. Cold blast furnace syndrome: a new source of toxic inhalation by nitrogen oxides

    OpenAIRE

    Tague, I; Llewellin, P.; Burton, K; Buchan, R.; Yates, D.

    2004-01-01

    Methods: Fourteen workers developed acute respiratory symptoms shortly after exposure to "air blast" from blast furnace tuyeres. These included chest tightness, dyspnoea, rigors, and diaphoresis. Chest radiographs showed pulmonary infiltrates, and lung function a restrictive abnormality. This report includes a description of clinical features of the affected workers and elucidation of the probable cause of the outbreak.

  8. The use of radioactive tracers to study metal and slag flow in blast furnaces

    International Nuclear Information System (INIS)

    The radionuclides 198Au, 60Co, 46Sc and 140La were used as tracers to determine flow characteristics and residence times for the iron and slag phases in an iron blast furnace hearth. This was done by injecting the tracers at various positions around the circumference of the furnace and measuring the induced activity of the iron and slag produced at the taphole

  9. Methods for monitoring heat flow intensity in the blast furnace wall

    Directory of Open Access Journals (Sweden)

    L'. Dorčák

    2010-04-01

    Full Text Available In this paper we present the main features of an online system for real-time monitoring of the bottom part of the blast furnace. Firstly, monitoring concerns the furnace walls and furnace bottom temperatures measurement and their visualization. Secondly, monitored are the heat flows of the furnace walls and furnace bottom. In the case of two measured temperatures, the heat flow is calculated using multi-layer implicit difference scheme and in the case of only one measured temperature, the heat flow is calculated using a method based on application of fractional-order derivatives. Thirdly, monitored is the theoretical temperature of the blast furnace combustion process in the area of tuyeres.

  10. Numerical Study of the Gas Distribution in an Oxygen Blast Furnace. Part 1: Model Building and Basic Characteristics

    Science.gov (United States)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2015-09-01

    Based on multifluid theory, transport phenomena theory, metallurgical reaction kinetics, thermodynamics, and computational fluid dynamics, a multifluid model for an oxygen blast furnace was established to evaluate the gas distribution in a furnace. The uneven distribution of recycling gas in oxygen blast furnaces was found to be a severe problem. This uneven distribution resulted from injecting a large amount of recycling gas into the furnace shaft. Gas distribution substantially affects the energy and heat utilization of an oxygen blast furnace. Therefore, the basic characteristics of the gas distribution in an oxygen blast furnace are illustrated. The results show that in the top of the oxygen blast furnace, the concentration differences of the CO and CO2 between the center and edge reach 7.8% and 11.7%, respectively. The recycling gas from the shaft tuyere only penetrates to two thirds the length of the radius.

  11. Sintering mechanism of blast furnace slag-kaolin ceramics

    International Nuclear Information System (INIS)

    A general ceramics processing scheme by cold uniaxial pressing and conventional sintering process have been used to prepare ceramics from mixtures of blast furnace slag (BFS) and kaolin (10%, 30% and 50% kaolin). The properties of the ceramics were studied by measuring linear shrinkage, bulk density, apparent porosity and mechanical properties of samples heated at temperatures from 800 oC to 1100 oC. The formed crystalline phases were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). Slag melt formed at relatively low temperatures (800-900 oC) modified the sintering process to liquid phase sintering mechanism. Combination of BFS with 10% kaolin gave the highest mechanical properties, densification and shrinkage at relatively low firing temperatures. The crystalline phases were identified as gehlenite (Ca2Al2SiO7) in both BFS and BFS with 10% kaolin samples. Anorthite (CaAl2Si2O8) phase increased with increasing kaolin contents. In the case of kaolin-rich mixtures (30% and 50% kaolin), increased expansion took place during firing at temperatures in the range 800-1000 oC. This effect could be attributed to the entrapment of released gases.

  12. Vanadium bioavailability in soils amended with blast furnace slag.

    Science.gov (United States)

    Larsson, Maja A; Baken, Stijn; Smolders, Erik; Cubadda, Francesco; Gustafsson, Jon Petter

    2015-10-15

    Blast furnace (BF) slags are commonly applied as soil amendments and in road fill material. In Sweden they are also naturally high in vanadium. The aim of this study was to assess the vanadium bioavailability in BF slags when applied to soil. Two soils were amended with up to 29% BF slag (containing 800 mg V kg(-1)) and equilibrated outdoors for 10 months before conducting a barley shoot growth assay. Additional soil samples were spiked with dissolved vanadate(V) for which assays were conducted two weeks (freshly spiked) and 10 months (aged) after spiking. The BF slag vanadium was dominated by vanadium(III) as shown by V K-edge XANES spectroscopy. In contrast, results obtained by HPLC-ICP-MS showed that vanadium(V), the most toxic vanadium species, was predominant in the soil solution. Barley shoot growth was not affected by the BF slag additions. This was likely due to limited dissolution of vanadium from the BF slag, preventing an increase of dissolved vanadium above toxic thresholds. The difference in vanadium bioavailability among treatments was explained by the vanadium concentration in the soil solution. It was concluded that the vanadium in BF slag is sparingly available. These findings should be of importance in environmental risk assessment. PMID:25917693

  13. Sequential extraction of inorganic mercury in dumped blast furnace sludge.

    Science.gov (United States)

    Földi, Corinna; Andrée, Corlin-Anna; Mansfeldt, Tim

    2015-10-01

    Blast furnace sludge (BFS) is an industrial waste with elevated mercury (Hg) contents due to the enrichment during the production process of pig iron. To investigate the potential pollution status of dumped BFS, 14 samples with total Hg contents ranging from 3.91 to 20.8 mg kg(-1) from five different locations in Europe were sequentially extracted. Extracts used included demineralized water (fraction 1, F1), 0.1 mol L(-1) CH3COOH?+?0.01 mol L(-1) HCl (F2), 1 mol L(-1) KOH (F3), 7.9 mol L(-1) HNO3 (F4), and aqua regia (F5). The total recovery ranged from 72.3 to 114 %, indicating that the procedure was reliable when adapted to this industrial waste. Mercury mainly resided in the fraction of "elemental" Hg (48.5-98.8 %) rather being present as slightly soluble Hg species associated with sludge particles. Minor amounts were found as mercuric sulfide (F5; 0.725-37.3 %) and Hg in crystalline metal ores and silicates (F6; 2.21-15.1 %). The ecotoxically relevant fractions (F1 and F2) were not of significance (F1,

  14. Evaluation of refractory lining wear of Companhia Siderurgica Nacional (CSN) blast furnaces

    International Nuclear Information System (INIS)

    The blast furnace refractory linings are submitted to unfavourable conditions such as alkalis attack, temperature, top pressure, abrasion and so forth... After studies on distribution and installation of radioactive sources with low activities in the refractory lining, it was possible to develop a new technique of thickness evaluation and attendance of wearing in the furnace lining. The viability analysis, simulated laboratory tests, localization, identification, installations and periodical measurements of the radioactive sources are described, as well the results obtained on the present campaign of CSN Blast Furnaces. (Author)

  15. Non-destructive testing (NDT) and inspection of the blast furnace refractory lining by stress wave propagation technique

    OpenAIRE

    Sadri, A.; Gebski, P.; Gordon, Y.

    2014-01-01

    Generally speaking, a blast furnace is the main equipment in Ironmaking and the campaign life of a blast furnace depends on its remaining hearth refractory lining [1]. The Acousto Ultrasonic- Echo (AU-E) is a stress wave propagation technique that uses time and frequency data analysis to determine coarse-grained material thicknesses, such as refractory and stave materials in operating blast furnaces. A mechanical impact on the surface of the structure (via a hammer or a mechanical impactor) g...

  16. Hot metal temperature prediction and simulation by fuzzy logic in a blast furnace

    International Nuclear Information System (INIS)

    This work describes the development and further validation of a model devoted to blast furnace hot metal temperature forecast, based on Fuzzy logic principles. The model employs as input variables, the control variables of an actual blast furnace: Blast volume, moisture, coal injection, oxygen addition, etc. and it yields as a result the hot metal temperature with a forecast horizon of forty minutes. As far as the variables used to develop the model have been obtained from data supplied by an actual blast furnaces sensors, it is necessary to properly analyse and handle such data. Especial attention was paid to data temporal correlation, fitting by interpolation the different sampling rates. In the training stage of the model the ANFIS (Adaptive Neuro-Fuzzy Inference System) and the Subtractive Clustering algorithms have been used. (Author) 9 refs

  17. Blast furnace operation with pulverized coal injection at different technological conditions

    International Nuclear Information System (INIS)

    Efficiency of pulverized coal injection (PCI) at two blast furnaces (BFs) in Spain and Ukraine which operate at different burden and blast conditions has been analyzed using statistical methods, calculation of material and heat balances and mathematical model. Effect of PCI on the parameters of blast furnace operation, pig iron quality and also on interactions between process parameters has been studied. At high-grade burden and high parameters of the combined blast, dependence of coke consumption rate on PC amounts is linear up to a high rate of PCI. At unfavorable burden and technological conditions dependence of the main furnace operating parameters on PC rate has extreme character. High efficiency of PC use can be achieved at the different conditions due to optimization of the technological regime. (Author) 31 refs

  18. Choice of technological regimes of a blast furnace operation with injection of hot reducing gases

    International Nuclear Information System (INIS)

    Injection rate of fossil fuels is limited because of drop in the flame temperature in the raceway and problems in the deadman region and the cohesive zone. The next step for obtaining a considerable coke saving, a better operation in the deadman as an well as increase in blast furnace productivity and minimizing the environmental impact due to a decrease in carbon dioxide emission would be injection by tuyeres of hot reducing gases (HRG) which are produced by low grade coal gasification or top gas regenerating. Use of HRG in combination with high pulverized coal injection PCI rate and oxygen enrichment in the blast could allow to keep and to increase the competitiveness of the blast furnace process. Calculations using a mathematical model show that the HRG injection in combination with pulverized coal (PC) and enriching blast with oxygen can provide an increase in PC rate up to 300-400 kg/tHM and a rise in the furnace productivity by 40-50% Blast furnace operation with full oxygen blast (100 % of process oxygen with the exception for the hot blast) is possible when HRG is injected. (Author) 54 refs

  19. Water leak detection in the cooling system of the blast furnace walls, by using radiotracer techniques

    International Nuclear Information System (INIS)

    The walls of a blast furnace are cooled by water that circulates through a system of copper plates inserted in the reflactory lining. These plates are fed by two independent annular pipes (or distribution rings) located around the furnace at different levels. Tritiated water was continuously injected in the upper ring, to investigate the presence of leaks in the plates fed by that distribution ring. During and after injection, water samples were periodically collected at the top of the blast furnace by condensing moisture from exit gases. The tritium activity, when present in the samples, indicates the existence of leaks in the cooling plates and, in some cases, allows to estimate the total water flow rate entering the blast furnace. Actual applications of this techniques are described. (Author)

  20. Alkali-activated blast furnace slag-zeolite cements and concretes

    International Nuclear Information System (INIS)

    The aim of this work has been the study of alkali-activated slag-zeolite cements and concretes based on them. Various compositions have been tested and some characteristics such as the compressive strength have been measured versus zeolite additions. A table lists the specific surface area and particle size distributions of different cements. The conclusions of the study are the following. First, alkali-activated slag cements and concretes based on them are effective for immobilization of radioactive wastes and the production of building structures, designed for high radiation load. Secondly, zeolite-containing mineral additions are able to increase the immobilization capacity and radiation resistance of alkali-activated blast furnace slag cements and concretes. Thirdly, the efficiency of different zeolite-containing additions - 10% to increase alkali-activated blast furnace slag-zeolite cement strength was established. It is with alkaline components of water-glass, sodium carbonate, sodium sulphate. Fourth, the effective way of introducing zeolite additions in alkali-activated blast furnace slag-zeolite cement is inter-grinding of the slag and addition. Increase in strength of alkali-activated blast furnace slag-zeolite cement stone is 40% higher than that of the stone of a mixture of separately milled components. Fifth, Alkali-activated blast furnace slag-zeolite cements with zeolite-containing additions with a compressive strength of 10.1 to 140 MPa; alkali-activated blast furnace slag-zeolite cements mortars with compressive strength from 35.2 to 97.7 MPa; alkali-activated blast furnace slag-zeolite cements concretes with compressive strength up to 84.5 MPa and frost resistant up to 800 cycles were obtained

  1. Tendency in development of radioisotope methods for control and automatization of blast furnaces and metallurgical processes

    International Nuclear Information System (INIS)

    To raise labour productivity in the metallurgy industry and to improve performance of blast furnaces in the period between capital repairs, a row of nuclear methods has been developed or was at the stage of experimental testing. Review is given of the tendencies of development of radioisotope methods of control and automatization of the blast furnace and metallurgic processes. Descriptions are given of nuclear methods for control and automatization of processes of materials transportation; continuous determination of the level of materials loading into the throat of blast furnace; observation of the wear of refractory lining of blast furnaces; determination of specific activity of cast iron; determination if the pre-set maximum and minimum levels of materials in bunkers on blast furnace bridge. Description is given of radiation sources of different activity, placed into containers, specific for each case of application as well as description of probes, - radiation detectors with Geiger-Mueller gas discharge counters. Depending on the field of application, probes can have a water cooling system. Description is given of probes commutation diagram as well as of the central part of installation ensuring processing of information coming from prodes and having control elements for automation of observation of technological processes and their control. The results are reflected on a mnemonic diagram for each of the process observed

  2. Multiscale dynamic analysis of blast furnace system based on intensive signal processing.

    Science.gov (United States)

    Chu, Yanxu; Gao, Chuanhou; Liu, Xiangguan

    2010-09-01

    In this paper, the Hilbert-Huang transform method and time delay embedding method are applied to multiscale dynamic analysis on the time series of silicon content in hot metal collected from a medium-sized blast furnace with the inner volume of 2500?m3. The results provide clear evidence of multiscale features in blast furnace ironmaking process. Ten intrinsic mode functions (IMFs) are decomposed from the silicon content time series; the presence of noninteger fractal dimension, positive finite Kolmogorov entropy, and positive finite maximum Lyapunov exponent are found in some IMF components. In addition, the coupling of subscale structures of blast furnace system is studied using the dimension of interaction dynamics and a robust algorithm for detecting interdependence. It is found that IMF(3) is the main driver in the coupling system IMF(2) and IMF(3) while for the coupling system IMF(3) and IMF(4) neither subsystem can act as the driver. All these provide a guideline for studying blast furnace ironmaking process with multiscale theory and methods, and may open way for more candidate tools to model and control blast furnace system in the future. PMID:20887042

  3. EFFECTS OF BLAST-FURNACE SLAG ON NATURAL POZZOLAN-BASED GEOPOLYMER CEMENT

    Directory of Open Access Journals (Sweden)

    MAHSHAD YAZDANIPOUR

    2011-03-01

    Full Text Available A number of geopolymer cement mixes were designed and produced by alkali-activation of a pumice-type natural pozzolan. Effects of blast-furnace slag on basic engineering properties of the mixes were studied. Different engineering properties of the mixes such as setting times and 28-day compressive strength were studied at different amounts of blast-furnace slag, sodium oxide content, and water-to-cement ratio. The mix comprising of 5 wt.% blast-furnace slag and 8 wt.% Na2O with a water-to-dry binder ratio of 0.30 exhibits the highest 28-day compressive strength, i.e. 36 MPa. Mixes containing 5 wt.% of ground granulated blast furnace slag showed the least efflorescence or best soundness. Laboratory techniques of X-ray diffractometry (XRD, fourier transform infrared spectroscopy (FTIR, and scanning electron microscopy (SEM were utilized for characterizing a number of mixes and studying their molecular and micro-structure. Investigations done by scanning electron microscopy confirm that smaller blast-furnace slag particles react totally while the larger ones react partially with alkaline activators and contribute to the formation of a composite microstructure.

  4. A Feasibility Study for Recycling Used Automotive Oil Filters In A Blast Furnace; FINAL

    International Nuclear Information System (INIS)

    This feasibility study has indicated that of the approximately 120,000 tons of steel available to be recycled from used oil filters (UOF's), a maximum blast furnace charge of 2% of the burden may be anticipated for short term use of a few months. The oil contained in the most readily processed UOF's being properly hot drained and crushed is approximately 12% to 14% by weight. This oil will be pyrolized at a rate of 98% resulting in additional fuel gas of 68% and a condensable hydrocarbon fraction of 30%, with the remaining 2% resulting as carbon being added into the burden. Based upon the writer's collected information and assessment, there appears to be no operational problems relating to the recycling of UOF's to the blast furnace. One steel plant in the US has been routinely charging UOF's at about 100 tons to 200 tons per month for many years. Extensive analysis and calculations appear to indicate no toxic consideration as a result of the pyrolysis of the small contained oil ( in the 'prepared' UOFs) within the blast furnace. However, a hydrocarbon condensate in the ''gasoline'' fraction will condense in the blast furnace scrubber water and may require additional processing the water treatment system to remove benzene and toluene from the condensate. Used oil filters represent an additional source of high quality iron units that may be effectively added to the charge of a blast furnace for beneficial value to the operator and to the removal of this resource from landfills

  5. Cold experiments on ligament formation for blast furnace slag granulation

    International Nuclear Information System (INIS)

    Rotary cup atomization for molten slag granulation is an attractive alternative to water quenching. However, the mechanism of disintegration of molten slag must be assessed. In the present study, a glycerol/water mixture was substituted for molten slag, and the mechanism of ligament formation in a rotary cup was investigated using photos taken by a high-speed camera. The effects of the angular speed and inner depth of the rotary cup on ligament disintegration was investigated. The results showed that one state of disintegration may transform into another state as the angular speed of the rotary cup increases at a given liquid flow rate. During ligament formation, the number of ligaments increased with an increase in the angular speed of the rotary cup, and a decrease in the diameter of ligament and liquid drop was observed. Moreover, the initial point of disintegration of the ligament moved to the lip of the rotary cup as the angular speed increased. An equation describing the relationship between the diameter of the liquid drop and various factors was used to predict the diameter of the liquid drop. A rotary cup with an inner depth of 30 mm was the best choice for granulation. The results of the present study will be useful for designing devices used in molten slag granulation. - Highlights: ?The results can be used in the granulation of molten blast furnace slag. ? The three different states of disintegration occur as the angular speed of rotary cup increases. ? The mechanism of ligament disintegration is analyzed. ? Eq. can be used to predict the diameter of liquid drop. ? A rotary cup with an inner depth of 30 mm is optimal for granulation.

  6. Model for Fast Evaluation of Charging Programs in the Blast Furnace

    Science.gov (United States)

    Mitra, Tamoghna; Saxén, Henrik

    2014-12-01

    A mathematical model for fast evaluation of charging programs in bell-less top blast furnaces is presented. The model describes the burden formation and descent procedures in the blast furnace, and can be used for designing charging programs. Experimental results in small scale were used to validate the model. The model was applied to a real charging program from a reference blast furnace. Through comparison between the estimated burden distribution and gas temperatures from an above-burden probe it was concluded that the model has captured the main features of the distribution of coke and pellets. The potential of using the model for the design of new charging programs was finally illustrated by analyzing the effect of small changes in the positions of the rings on the arising burden distribution.

  7. Industrial experiment on using coke with a size of more than 20 mm in blast furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Filonenko, Yu.Ya.; Sobolev, S.Ya.; Razgonov, V.A.; Blokhin, V.S.; Urbanovich, G.E.

    1984-01-01

    The blast furnaces of the Novolipetsk Metallurgical Association have been functioning with coke belonging to the >40 mm class until recently. The possibility of using coke belonging to the 40-25 mm class in a blast furnace process was investigated in view of the considerable shortage of over 40 mm cake. Implementing this measure makes is possible to increase metallurgical coke resources by 7-9%. In order to evaluate the possibility of using coke lumps measuring 40-25 mm in a blast-furnace smelting process, indices of the physicomechanical properties of individual metallurgical coke classes were investigated. Data on the mechanical tests of coke belonging to the following classes: >80, 80-60, 60-40, and 40-25 mm are presented. The coke came from batteries 1-4; the tests were run in a lab drum.

  8. Control of the refractory lining wear in blast furnaces, using a radiotracer technique

    International Nuclear Information System (INIS)

    Small metal 60Co sources, double encapsulated with quartz and alumina, were inserted (at different depths and levels) into the refractory bricks of the blast furnace walls, and the initial radioactivity emerging at each location recorded as a reference data for future measurements. The displacement of the charge inside the blast furnace originates a progressive wear of the refractory lining and after certain time, the inner sources will begin to be scaped off from the wall and then dissolved in the molten iron. By periodically monitoring the radiation level at the points where the sources were placed, it is possible to know if some of them was removed by the wearing process. This, in turn, will indicate the thickness of refractory material lost in each location making of the blast furnace, as a function of time. The practical application of this method in the Brazilian steel industry is reported. (Author)

  9. CFD modeling of multiphase reacting flow in blast furnace shaft with layered burden

    International Nuclear Information System (INIS)

    The ironmaking blast furnace is a counter-current chemical reactor which includes the ascending gas flow and the counter-current descending porous bed (burden). A Computational Fluid Dynamics (CFD) model has been developed to simulate the multiphase reacting flow in blast furnace shaft. The gas flow dynamics, burden movement, chemical reactions, heat and mass transfer between the gas phase and burden phase are included in the CFD model. The blast furnace burden consists of alternative layers of iron ore and coke. A novel methodology is proposed to efficiently model the effects of alternative burden layer structure on gas flow, heat transfer, mass transfer and chemical reactions. Different reactions and heat transfer characteristics are applied for difference types of layer. In addition, the layered CFD model accurately predicts the Cohesive Zone (CZ) shape where the melting of solid burden taking place. The shape and location of the CZ are determined by an iterative method based on the ore temperature distribution. The theoretical formation and the methodology of the CFD model are presented and the model is applied to simulate industry blast furnaces. The proposed method can be applied to investigate the blast furnace shaft process and other moving bed system with periodic burden structure configuration. - Highlights: •A novel methodology is proposed to efficiently model the blast furnace shaft with layered burden. •The effects of layered burden on flow, heat transfer, and chemical reactions are considered in the model. •The shape and location of the cohesive zone is determined by an iterative method

  10. Industrial testing of the use of larger than 20 mm size coke in blast furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Filonenko, Yu.Ya.; Sobolev, S.Ya.; Razgonov, V.A.; Blokhin, V.S.; Urbanovich, G.I.

    1984-09-01

    Physical and mechanical properties of several size classes of coke were investigated in order to determine the feasibility of using the 40-25 mm class in blast furnace smelting. It was shown in a laboratory drum that this class is characterized by high strength, low crushability and low abraidability. In spite of low gas permeability characterisitcs, it was judged to be usable for blast furnace smelting. Furnaces of 1000, 2000 and 3200 m/sup 3/ capacities at the Novolipetsk metallurgical plant were converted in 1981 to using the 40-25 mm class and in 1982, to the greater than 20 mm size coke (which displayed the same characteristics as the 40-25 mm class) with minimum reduction in the productivity of the furnaces. 6 references.

  11. Influence of Hot Metal Flow State to the Hearth Flow Field during Blast Furnace Tapping

    OpenAIRE

    Hong-Wei Guo; Bing-Ji Yan; Jian-Liang Zhang; He-Lan Liang; Yi-Li Liu

    2013-01-01

    Blast furnace tapping is one of the most important aspects of BF iron-making, a process during which the ideal state is for the molten iron to remain the invariant and the level of liquid to remain stable. However, due to the viscosity of molten iron, the liquid level will tilt to one side near the tap-hole, causing the iron flow field during blast furnace tapping to change with time. This research simulated two cases of horizontal and inclined molten iron liquid levels in the process of blas...

  12. Properties of coke sampled at tuyere level and its correlation with operational data of blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, N.

    1984-01-01

    The short article is a synopsis of a paper presented to the 107th Meeting of the ISIJ in April 1984. It reports a correlation of the properties of coke sampled at tuyere level with blast furnace operation and permeability resistance. The fraction of fine coke production at tuyere level decreases as the flame temperature decreases, tuyere blast velocity decreases and the index of coke strength after reaction increases.

  13. Bio-fuels use in blast furnace ironmaking to mitigate GHG emissions

    Energy Technology Data Exchange (ETDEWEB)

    Ka Wing Ng; Hutny, W.; MacPhee, T.; Gransden, J.; Price, J. [CANMET Energy Technology Center, Nepean, ON (Canada)

    2008-07-01

    The feasibility of substituting fossil fuel by biomass in the blast furnace ironmaking process as investigated. The use of biomass in the blast furnace ironmaking both was an injectant and addition to metallurgical coke was studied in this work. Charcoal was found to be the most suitable biomass material for substituting coal directly injected into the blast furnace. Using charcoal the ironmaking ability of the furnace can be preserved and GHG emissions from the blast furnace-cokemaking system can be mitigated. Bio-coke was prepared by addition of charcoal to the cokemaking coal blend. It was observed that the cold strength of the resultant bio-coke was not significantly affected. However, the prepared bio-coke is weak at elevated temperature due to its high mineral matter content originating from charcoal. The mineral matter content of charcoal can be effectively reduced by acid leaching and the strength of bio-coke can be further improved. It was estimated that complete substitution of coal injection by charcoal and application of bio-coke containing 10% of carbon originating from charcoal could reduce the annual CO{sub 2} emission associated with the Canadian ironmaking processes from 13.9 Mt/yr to 9.6 Mt/yr without sacrificing productivity. 9 refs., 8 figs., 2 tabs.

  14. Production analysis of methanol and hydrogen of a modificated blast furnace gas using nuclear energy of the high temperature reactor

    International Nuclear Information System (INIS)

    Modern blast furnaces are operated with a coke ration of 500 kg/t pig iron. The increase of the coke ratio to 1000 kg/t pig iron raises the content of carbon monoxide and hydrogen in the blast furnace gas. On the basis of a blast furnace gas modificated in such a way, the production of methanol and hydrogen is investigated under the coupling of current and process heat from the high temperature reactor. Moreover the different variants are discussed, for which respectively a material and energetic balance as well as an estimation of the production costs is performed. Regarding the subsequent treatment of the blast furnace gas it turns out favourably in principle to operate the blast furnace with a nitrogen-free wind consisting only of oxygen and steam. The production costs show a strong dependence on the raw material costs, whose influence is shown in a nomograph. (orig.)

  15. Composite cements containing natural pozzolan and granulated blast furnace slag

    Directory of Open Access Journals (Sweden)

    Irassar, E. F.

    2006-09-01

    Full Text Available For reasons of market demand and Portland cement production,the manufacture of cements with two or more separately ground additions to produce customized cements is becoming common practice.When pozzolan or slag content in this type of cements is high, however, the initial strength of the resulting product may be adversely impacted. This problem can be minimized by activating one or both of the replacement materials. The present study analyzes the effect of Portland cement additions such as physically activated natural pozzolan(up to 20% and/or granulated blast furnace slag (up to 35% on mortar flexural and compressive strength. The results show that higher strength is attained in ternary than binary cements. Initially (2 and 7 days, the highest compressive strengths are reached by mortars with up to 13% natural pozzolan and 5% slag, whereas at later ages mortars with larger proportions of additions are found to perform best.Debido a las exigencias del mercado y de la producción de cemento Portland, es cada vez más frecuente la elaboración de cementos con dos o más adiciones a partir de la molienda separada de sus constituyentes, dando origen a la formulación de los cementos a medida.Cuando el contenido de adiciones es alto, la utilización de puzolana y escoria en este tipo de cementos presenta la peculiaridad de disminuir la resistencia inicial del cemento resultante. Sin embargo, si algunas o ambas adiciones se activan, este problema puede minimizarse. En este trabajo se analiza la influencia de la incorporación al cemento Portland de puzolana natural (hasta 20% activada físicamente y/o escoria granulada de alto horno (hasta 35% sobre la resistencia a flexión y a compresión de morteros. Los resultados indican que los cementos ternarios presentan un mejor comportamiento resistente que los cementos binarios. Las máximas resistencias a compresión en las primeras edades (2 y 7 díasse alcanzan con hasta 13% de puzolana natural y 5% de escoria, mientras que a edades más avanzadas se trasladan a mayores contenidos de puzolana y escoria.

  16. Data-driven modeling based on volterra series for multidimensional blast furnace system.

    Science.gov (United States)

    Gao, Chuanhou; Jian, Ling; Liu, Xueyi; Chen, Jiming; Sun, Youxian

    2011-12-01

    The multidimensional blast furnace system is one of the most complex industrial systems and, as such, there are still many unsolved theoretical and experimental difficulties, such as silicon prediction and blast furnace automation. For this reason, this paper is concerned with developing data-driven models based on the Volterra series for this complex system. Three kinds of different low-order Volterra filters are designed to predict the hot metal silicon content collected from a pint-sized blast furnace, in which a sliding window technique is used to update the filter kernels timely. The predictive results indicate that the linear Volterra predictor can describe the evolvement of the studied silicon sequence effectively with the high percentage of hitting the target, very low root mean square error and satisfactory confidence level about the reliability of the future prediction. These advantages and the low computational complexity reveal that the sliding-window linear Volterra filter is full of potential for multidimensional blast furnace system. Also, the lack of the constructed Volterra models is analyzed and the possible direction of future investigation is pointed out. PMID:22128000

  17. Simultaneous Measurements of Temperature and Iron-Slag Ratio at Taphole of Blast Furnace

    Science.gov (United States)

    Sugiura, M.; Shinotake, A.; Nakashima, M.; Omoto, N.

    2014-07-01

    As the initial process in an integrated steel-making plant, molten iron is produced in a blast furnace. The molten iron has a temperature between 1700 K and 1900 K. The outflow stream discharged from a taphole comprises the molten iron and slag (which is a mixture of molten oxides). Monitoring of the stream temperature is important because it has information on the thermal condition inside the blast furnace. A newly developed simultaneous measurement technique for temperature and iron-slag ratio is reported. A monochromatic CCD camera with a short exposure time is used to obtain a thermal image of the rapidly moving stream. The thermal image has a marble-like pattern caused by the physical separation of the iron and slag and their different optical properties. Iron thermometry is realized by automatically detecting the peak of the iron gray-level distribution on a histogram. Meanwhile, the thermal radiance of the semitransparent slag varies as a function of the thickness. The slag temperature is calculated from the maximum gray level, presuming that the emissivity of the slag is constant at a thick slag part. The slag ratio is measured by counting the number of pixels on the histogram. A field test was carried out at an operating blast furnace. The iron temperature, slag temperature, and slag ratio were successfully measured. This multiple image measurement is expected to be the new information source for stable blast furnace operation.

  18. 'Salem Box Test' to predict the suitability of metallurgical coke for blast furnace ironmaking

    Scientific Electronic Library Online (English)

    K.B., Nagashanmugam; M.S., Pillai; D., Ravichandar.

    2015-02-01

    Full Text Available Blast furnace performance depends strongly on the coke reactivity index (CRI) and coke strength after reaction (CSR) properties. An innovative and cost-effective method, known as the Salem Box Test, has been developed to prevent the mass production of inferior coke unsuitable for blast furnace use. [...] This method consists of coal carbonization on a micro-scale and involves charging approximately 18 kg of coal blend in a stainless steel box, carbonizing it together with coal cake in the plant coke ovens, and testing the coke produced for CRI and CSR to determine its suitability for blast furnace use. Only coal blends that yield coke with CRI 64% are permitted for mass production, and other coal blends are either rejected or the blending ratios adjusted in an attempt to upgrade them. The experimental results reveal that, for a given coal blend, the quality of coke produced by the Salem Box Test is comparable with that produced by bulk production, indicating that the test is acceptable as a screening tool for regular use. The present paper describes the methodology and application of Salem Box Test to predict the suitability of coke for blast furnace use at JSW Steel Limited, Salem Works (JSWSL), and illustrates its advantages in adjusting the coal blending ratio to produce superior coke, in detecting coal contamination, and in preventing bulk production of inferior coke.

  19. Hot metal temperature prediction by neural networks in the blast furnace

    International Nuclear Information System (INIS)

    Based on a simplified model, the underlying temperature criteria is proposed as a method to study the temperature trends in a blast furnace. As an application, a neural network able to forecast hot metal temperatures from 2 to 16 h in advance (with decreasing precision) has been built. This neural network has been designed to work at real time in a production plant. (Author)

  20. Analysis of changes in the chemical composition of the blast furnace coke at high temperatures

    Directory of Open Access Journals (Sweden)

    A. Konstanciak

    2012-12-01

    Full Text Available Purpose: The main purpose of this paper was to analyze the behavior of coke in the blast furnace. The analysis of changes in chemical composition of coke due to impact of inert gas and air at different temperatures was made. The impact of the application of the thermoabrasion coefficient on the porosity of coke was also analyzed.Design/methodology/approach: By applying the Computer Thermochemical Database of the TERMO system (REAKTOR1 and REAKTOR3 three groups of substances can be distinguished. The chemical composition of blast furnace coke and the results of calculations of changes of chemical composition of coke heat treated under certain conditions were compared. The structural studies of these materials were presented.Findings: The results of the analysis of ash produced from one of Polish cokes was taken for consideration. This is not the average composition of Polish coke ashes, nevertheless it is representative of most commonly occurring chemical compositions.Practical implications: Thanks to the thermochemical calculations it is possible to predict ash composition after the treatment in a blast furnace. Those information was crucial and had an actual impact on determining the coke quality.Originality/value: Presentation of the analytical methods which, according to author, can be very useful to evaluate and identify the heat treatment for blast furnaces cokes. The research pursued represents part of a larger project carried out within the framework of Department Extraction and Recycling of Metals, Czestochowa University of Technology.

  1. Potential modification of hydration of alkali activated mixtures from granulated blast furnace slag and fly ash.

    Czech Academy of Sciences Publication Activity Database

    Tomková, V.; Ov?a?ík, F.; Vl?ek, J.; Ov?a?íková, H.; Topinková, M.; Vavro, M.; Martinec, Petr

    2012-01-01

    Ro?. 56, ?. 2 (2012), s. 168-176. ISSN 0862-5468 R&D Projects: GA ?R GA106/09/0588 Institutional support: RVO:68145535 Keywords : alkali-activated materials * blast furnace slag * mechanical activation * fly ash Subject RIV: DD - Geochemistry Impact factor: 0.418, year: 2012 http://www.ceramics-silikaty.cz/2012/pdf/2012_02_168.pdf

  2. Graphitization of Coke and Its Interaction with Slag in the Hearth of a Blast Furnace

    Science.gov (United States)

    Li, Kejiang; Zhang, Jianliang; Liu, Yanxiang; Barati, Mansoor; Liu, Zhengjian; Zhong, Jianbo; Su, Buxin; Wei, Mengfang; Wang, Guangwei; Yang, Tianjun

    2016-01-01

    Coke reaction behavior in the blast furnace hearth has yet to be fully understood due to limited access to the high temperature zone. The graphitization of coke and its interaction with slag in the hearth of blast furnace were investigated with samples obtained from the center of the deadman of a blast furnace during its overhaul period. All hearth coke samples from fines to lumps were confirmed to be highly graphitized, and the graphitization of coke in the high temperature zone was convinced to start from the coke surface and lead to the formation of coke fines. It will be essential to perform further comprehensive investigations on graphite formation and its evolution in a coke as well as its multi-effect on blast furnace performance. The porous hearth cokes were found to be filled up with final slag. Further research is required about the capability of coke to fill final slag and the attack of final slag on the hearth bottom refractories since this might be a new degradation mechanism of refractories located in the hearth bottom.

  3. AIR POLLUTION IMPACTS WHEN QUENCHING BLAST FURNACE SLAG WITH CONTAMINATED WATER

    Science.gov (United States)

    The report gives results of an effort to determine if a potential alternative to treatment prior to discharge of coke plant wastewater will result in a significant increase in emissions to the atmosphere. The alternative is using the wastewater, untreated, to quench blast furnace...

  4. Injections in the iron blast furnace: a graphics study by means of the rist operating diagram

    Science.gov (United States)

    Kundrat, D. M.; Miwa, T.; Rist, A.

    1991-06-01

    A graphics study of injections in the iron blast furnace, made over 20 years ago in the Rist operating diagram, has been extended and refined further. The procedure is enlarged to treat many types of injections available for the blast furnace, including injection of an inert gas heated by a plasma. At issue is the behavior in the diagram of lines associated with the specific coke and fuel rates for the process as an injection is made. For this, new geometrical properties for the diagram are employed, namely, the decomposition of lines and derivation of pivots governing their rotation in the diagram. This results in an analogue model that facilitates interpretation and comprehension of the effect of an injection on the process while predicting quantitatively thermochemical changes in the furnace over a wide range of operation.

  5. A Feasibility Study for Recycling Used Automotive Oil Filters In A Blast Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Ralph M. Smailer; Gregory L. Dressel; Jennifer Hsu Hill

    2002-01-21

    This feasibility study has indicated that of the approximately 120,000 tons of steel available to be recycled from used oil filters (UOF's), a maximum blast furnace charge of 2% of the burden may be anticipated for short term use of a few months. The oil contained in the most readily processed UOF's being properly hot drained and crushed is approximately 12% to 14% by weight. This oil will be pyrolized at a rate of 98% resulting in additional fuel gas of 68% and a condensable hydrocarbon fraction of 30%, with the remaining 2% resulting as carbon being added into the burden. Based upon the writer's collected information and assessment, there appears to be no operational problems relating to the recycling of UOF's to the blast furnace. One steel plant in the US has been routinely charging UOF's at about 100 tons to 200 tons per month for many years. Extensive analysis and calculations appear to indicate no toxic consideration as a result of the pyrolysis of the small contained oil ( in the 'prepared' UOFs) within the blast furnace. However, a hydrocarbon condensate in the ''gasoline'' fraction will condense in the blast furnace scrubber water and may require additional processing the water treatment system to remove benzene and toluene from the condensate. Used oil filters represent an additional source of high quality iron units that may be effectively added to the charge of a blast furnace for beneficial value to the operator and to the removal of this resource from landfills.

  6. The Effect on the Propagation of Blast Pulses of Dry and Dampened Granular Media

    Science.gov (United States)

    Proud, William; Badham, Henry; Chalmers, Max; Nguyen, Thuy-Tien

    2015-06-01

    The propagation of stress through granular and dampened granular material has been reported in previous papers. With increasing presence of liquid in granular beds the transmission of blast and pressure pulse changes from one of percolation through the bed pores to one of wave transmission through the granules of the bed. It has been shown that limited amounts liquid can retard pressurisation within confined blast-loaded beds by approximately an order of magnitude. This study presents data on percolation through dry and dampened granular beds using a shock tube as the pressure driver. In this scenario the effect of the bed on initial pressure pulse is studied in greater detail. The effect of particle shape and size was investigated using angular grains of quartz sand as well as smooth glass microspheres. The effect of addition of liquids is presented. The pressure range studied is in the range associated with blast injury and with far field effects produced by explosive devices. The Institute of Shock Physics acknowledges the support of AWE, Aldermaston, UK and Imperial College London. The Centre for Blast Injury Studies acknowledges the support of the Royal British Legion and Imperial College London.

  7. Using coal-dust fuel in Ukrainian and Russian blast furnaces

    Energy Technology Data Exchange (ETDEWEB)

    A.A. Minaev; A.N. Ryzhenkov; Y.G. Banninkov; S.L. Yaroshevskii; Y.V. Konovalov; A.V. Kuzin [Donetsk National Technical University, Donetsk (Russian Federation)

    2008-02-15

    Ukrainian and Russian blast-furnace production falls short of the best global practices. It is no secret that, having switched to oxygen and natural gas in the 1960s, the blast-furnace industries have improved the batch and technological conditions and have attained a productivity of 2.5 and even 3 t/(m{sup 3} day), but have not been able to reduce coke consumption below 400 kg/t, which was the industry standard 40 years ago. The situation is particularly bad in Ukraine: in 2007, furnace productivity was 1.5-2 t/m{sup 3}, with a coke consumption of 432-530 kg/t. Theoretical considerations and industrial experience over the last 20 years show that the large-scale introduction of pulverized fuel, with simultaneous improvement in coke quality and in batch and technological conditions, is the only immediately available means of reducing coke consumption considerably (by 20-40%). By this means, natural-gas consumption is reduced or eliminated, and the efficiency of blast-furnace production and ferrous metallurgy as a whole is increased.

  8. Modelling and prediction of pig iron variables in the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Saxen, H.; Laaksonen, M.; Waller, M. [Aabo Akademi, Turku (Finland). Heat Engineering Lab.

    1996-12-31

    The blast furnace, where pig iron for steelmaking is produced, is an extremely complicated process, with heat and mass transfer and chemical reactions between several phases. Very few direct measurements on the internal state are available in the operation of the process. A main problem in on-line analysis and modelling is that the state of the furnace may undergo spontaneous changes, which alter the dynamic behaviour of the process. Moreover, large internal disturbances frequently occur, which affect the product quality. The work in this research project focuses on a central problem in the control of the blast furnace process, i.e., short-term prediction of pig iron variables. The problem is of considerable importance for fuel economy, product quality, and for an optimal decision making in integrated steel plants. The operation of the blast furnace aims at producing a product (hot metal) with variables maintained on a stable level (close to their setpoints) without waste of expensive fuel (metallurgical coke). The hot metal temperature and composition affect the downstream (steelmaking) processes, so fluctuations in the pig iron quality must be `corrected` in the steel plant. The goal is to develop a system which predicts the evolution of the hot metal variables (temperature, chemical composition) during the next few taps, and that can be used for decision-making in the operation of the blast furnace. Because of the complicated behaviour of the process, it is considered important to include both deterministic and stochastic components in the modelling: Mathematical models, which on the basis of measurements describe the physical state of the process, and statistical (black-box) models will be combined in the system. Moreover, different models will be applied in different domains in order to capture structural changes in the dynamics of the process SULA 2 Research Programme; 17 refs.

  9. The Iron Blast Furnace: A Study in Chemical Thermodynamics.

    Science.gov (United States)

    Treptow, Richard S.; Jean, Luckner

    1998-01-01

    Discusses the furnace from a chemical thermodynamics perspective. Examines the enthalpy, entropy, and free energy change for each reaction of importance. These properties are interpreted on the molecular level then used to deduce the conditions necessary for each reaction to occur in its intended direction. Chemical kinetics is also discussed.…

  10. Improvement in the utilization of blast furnace gas; Mejora en la utilizacion de gas de alto horno

    Energy Technology Data Exchange (ETDEWEB)

    Antonilli, Ricardo [Tenaris S.A. (Argentina); Kozicki, Alejandro [Ternium Siderar S.A. (Argentina)

    2009-11-01

    In the thermoelectric power plant of Siderar reforms were implemented to maximize the use of blast furnace gas, obtaining a reduction of flaring (venting) of process gases through optimizing the use of blast furnace gas, with consequent decrease of global warming due to the reduction of flare gases directly to the atmosphere and decrease the use of alternative fuels (fuel oil, natural gas) or purchasing power and hence a Non-renewable natural resource. (author)

  11. Review and evaluation of alternative processes to the blast furnace; Revision y evaluacion de procesos alternativos al horno alto

    Energy Technology Data Exchange (ETDEWEB)

    Conejo Nava, A.

    2000-07-01

    A critical review on the alternative processes to the blast furnace, involving both solid and liquid state reduction is presented. Process comparison allows to identify advantages and disadvantages of each type of processes as well as to highlight the major challenges faced in order to compete with the traditional iron making route: the blast furnace, which today rules the production of iron units worldwide. (Author) 31 refs.

  12. Deposition of 60Co and 137Cs adsorbed on zeolite in matrices on the blast furnace slag

    International Nuclear Information System (INIS)

    The experimental data (leaching tests and compressive strength measurements) are presented for case the radionuclides from model water solution and radioactive waste water were uptake on natural and chemically modified granular zeolitic tuffite which show improved sorption ability and were subsequently incorporated into cement casts on blast furnace slags (BSF) basis. The all experiment were carried out with zeolite tuffite from Nizny Hrabovec, Slovak Republic. The natural zeolite was treated by the NaOH solution. The blends of individual components were casted into rectangular prism moulds (1 x 1 x 3 cm). The cast consisted invariably of 90% of BSF, 10% of fine zeolite and solution of water glass and to this basic mixture were added either 10 or 20% granular active, or non active zeolite during the mix formation, in excess to content of previous solid components. The water/cement ratio varied in interval 0.32-0.40. Model solutions labelled by cesium-137 or cobalt-60 have been used for sorption experiment and real waste water concentrate from NPP Jaslovske Bohunice as well. The real water consisted of cesium-134, cesium-137, cobalt-60, in borate and nitrate form. The radioactivity of dry cement casts was measured in 4? geometry. The leaching experiments were performed in three solutions: water (W), 0.03 M HCl (A) and 0.04 M NaOH (B). The mechanical properties of sample with non active granular zeolites and their corrosion characteristics as reflected by the bulk density changes. The experiments showed that leaching of radionuclides, which were sorbed from solution and radioactive waste water, in water and bases solution were negligible. Changes of radioactivity of casts, prepared from model solution, in acid solution, which were less than 5%. The mechanical strength of prepared composites is favourable and shows good compatibility of zeolitic additives with a basic matrix. Leaching experiments and mechanical strength are hopeful and show good retention of observed radionuclides in samples exposed in leaching solutions. 2 tabs., 3 figs

  13. Ground granulated blast furnace slag efficiency coefficient (k value) in concrete. Applications and limits

    International Nuclear Information System (INIS)

    Recently, a k-value for ground granulated blast-furnace slag or k-value has been added to the revision of the European standard EN 206-1:2000. The proposed values during the discussions in the working groups were very different because in most of cases the compressive strength was the only characteristic considered; while only in few cases the concrete durability was taken into account when ground granulated blast-furnace slag is added directly to the mix. Advantages and disadvantages of the k-values found in the literature are discussed in this paper. The final conclusion may be summarised suggesting a logical proposal of addressing to each country the choice of the k-value in function of the concrete application, environment and placing conditions selected according to their own experience. (Author) 15 refs.

  14. Mechanism Research on Melting Loss of Coppery Tuyere Small Sleeve in Blast Furnace

    Science.gov (United States)

    Chai, Yi-Fan; Zhang, Jian-Liang; Ning, Xiao-Jun; Wei, Guang-Yun; Chen, Yu-Ting

    2016-01-01

    The tuyere small sleeve in blast furnace works under poor conditions. The abnormal damage of it will severely affect the performance of the blast furnace, thus it should be replaced during the damping down period. So it is of great significance that we study and reduce the burnout of tuyere small sleeve. Melting loss is one case of its burnout. This paper studied the reasons of tuyere small sleeve's melting loss, through computational simulation and microscopic analysis of the melting section. The research shows that the temperature of coppery tuyere small sleeve is well distributed when there is no limescale in the lumen, and the temperature increases with the thickness of limescale. In addition, the interruption of circulating water does great harm to the tuyere small sleeve. The melting loss of tuyere small sleeve is caused by iron-slag erosion, with the occurrence of the melt metallurgical bonding and diffusion metallurgical combination.

  15. Reactions in the Lower Part of the Blast Furnace with Focus on Silicon

    OpenAIRE

    Gustavsson, Joel

    2004-01-01

    The thermodynamic conditions for the behaviour of silicon in the lower part of the blast furnace have been the focus of the thesis. More specifically, the influences of temperature, carbon activity, total gas pressure and Fe reoxidation on silicon have been studied. Calculations show that an increased temperature gives higher equilibrium ratio between silicon in hot metal and slag. Furthermore, laboratory reduction studies shows that the carbon activity in the cohesive zone increase with an i...

  16. Plastic wastes, lube oils and carbochemical products as secondary feedstocks for blast-furnace coke production

    OpenAIRE

    Melendi Espina, Sonia; Barriocanal Rueda, Carmen; Álvarez García, Ramón; Díez Díaz-Estébanez, M.ª Antonia

    2009-01-01

    Plastic wastes, lube oils and coal-tar are evaluated, individually and combined, as additives to coal blends for the production of blast-furnace coke. The effects of adding 2 wt% of potential additives or their mixtures (50:50 w/w) on the coking capacity of coal, the pressure generated during the coking process and the coke quality parameters were evaluated. Using a combination of polyolefin waste and lubricating oil with high-boiling hydrocarbons has the beneficial...

  17. Biomass as blast furnace injectant : Considering availability, pretreatment and deployment in the Swedish steel industry

    OpenAIRE

    WANG Chuan; Mellin, Pelle; Lövgren, Jonas; Nilsson, Leif; Yang, Weihong; Salman, Hassan; Hultgren, Anders; Larsson, Mikael

    2015-01-01

    We have investigated and modeled the injection of biomass into blast furnaces (BF), in place of pulverized coal (PC) from fossil sources. This is the easiest way to reduce CO2 emissions, beyond efficiency improvements. The considered biomass is either pelletized, torrefied or pyrolyzed. It gives us three cases where we have calculated the maximum replacement ratio for each. It was found that charcoal from pyrolysis can fully replace PC, while torrefied material and pelletized wood can replace...

  18. Towards Early Age Characterisation of Eco-Concrete Containing Blast-Furnace Slag and Limestone Filler

    OpenAIRE

    Carette, Jerome

    2015-01-01

    It is estimated that concrete represents 5% of the anthropogenic CO2 emissions, mainly originating from the production of cement, the most essential component of concrete. The recent awareness to the environmental challenges facing our civilization has led the cement industry to consider substituting cement by mineral additions, by-products of existing industries. In this work, a combination of limestone filler and blast furnace slag is used to design an “eco-concrete”, defined as a concrete ...

  19. Mineral Reactions and Slag Formation During Reduction of Olivine Blast Furnace Pellets

    OpenAIRE

    Ryösä, Elin

    2008-01-01

    The present work focuses on mineral reactions and slag formation of LKAB olivine iron ore pellets (MPBO) subjected to reducing conditions in the LKAB experimental blast furnace (EBF). The emphasis is on olivine reactions with surrounding iron oxides. Many factors influence the olivine behaviour. The study was performed by use of micro methods; optical microscopy, micro probe analysis, micro Raman and Mössbuer spectroscopy and thremodynamic modeling. During manufacturing, in oxidising atmosphe...

  20. A new concept of auxiliary fuel injection through tuyeres in blast furnaces developed by numerical simulations

    OpenAIRE

    Bruno Orlando de Almeida Santos; Breno Totti Maia; Fabricio Silveira Garajau; Marcelo de Souza Lima Guerra; Paulo Santos Assis; José Eduardo Mautone Barros

    2014-01-01

    The Injection of powdered materials in blast furnaces is a great option for reducing costs, increasing productivity and satisfy the environmental norms. Thus, this paper presents a study on the use of a flame stabilization system with rotation, designed to promote greater coal injection in the combustion zone, reducing losses and increasing the efficiency of the equipment. A physical model was used to evaluate scattering of pulverized fuel and is compared with numerical results in the same sc...

  1. Development of engineered cementitious composites with limestone powder and blast furnace slag:

    OpenAIRE

    Zhou, J.; Qian, S.; Sierra Beltran, M.G.; Ye, G; Van Breugel, K.; Li, V.C.

    2009-01-01

    Nowadays limestone powder and blast furnace slag (BFS) are widely used in concrete as blended materials in cement. The replacement of Portland cement by limestone powder and BFS can lower the cost and enhance the greenness of concrete, since the production of these two materials needs less energy and causes less CO2 emission than Portland cement. Moreover, the use of limestone powder and BFS improves the properties of fresh and hardened concrete, such as workability and durability. Enginee...

  2. Modeling of a self-healing process in blast furnace slag cement exposed to accelerated carbonation:

    OpenAIRE

    Zemskov, S.V.; Ahmad, B.; Copuroglu, O.; Vermolen, F. J.

    2013-01-01

    In the current research, a mathematical model for the post-damage improvement of the carbonated blast furnace slag cement (BFSC) exposed to accelerated carbonation is constructed. The study is embedded within the framework of investigating the effect of using lightweight expanded clay aggregate, which is incorporated into the impregnation of the sodium mono-fluorophosphate (Na-MFP) solution. The model of the self-healing process is built under the assumption that the position of the carbonati...

  3. Coke, char and organic waste behaviour in the blast furnace with high injection rate

    OpenAIRE

    Gudenau, H. W.; Senk, D.; Fukada, K.; Babich, A.; Froehling, C.; Formoso Prego, Antonio; Alguacil, Francisco José; Cores Sánchez, A.

    2003-01-01

    [EN] Blast furnace operation with low coke rate, high amount of auxiliary hydrocarbons and use of nut coke causes a change in coke quality requirements. In particular, not burned in the raceway residues of injected substances (char and ash) can influence the coke behaviour. Therefore combustion efficiency of various organic wastes with and without pulverized coal injection (PCI) and coal char has been investigated under the raceway simulation conditions. Mixing of various subst...

  4. Solidification of radioactive liquid waste - blast furnace slag as a binding agent

    International Nuclear Information System (INIS)

    During the reprocessing of spent Material Test Reactor (MTR) fuel elements from research reactor DIDO a radioactive waste solution is produced. Besides the radiotoxical elements, the waste solution contains aluminium from the cladding material of the spent fuel element and sodium hydroxide which is given to the acidic waste solution to reach a pH value between 12 and 13. After the neutralisation, the waste solution is solidified in a slag rich cement matrix. The final solidified product has to be assessed for a final disposal in a deep geological repository. One aspect of the assessment is related to intrinsic factors inherent to the solidified waste physical properties and the interaction between the binding agent and the waste solution. Another aspect of the safety assessment is related to the hydrolytic behaviour of the final cemented waste product under deep geological disposal conditions. The alkalinity of the waste solution acts as an activator for the hydration of the blast furnace slag. The rate of slag hydration decreases at late ages due to the formation of a denser microstructure of reaction products around the slag particles. The solidification of the waste solution with pure blast furnace slag and slag rich matrices leads to significant compressive strength. The effect is more marked for the waste solution cemented with only blast furnace slag. The solidification with blast furnace slag enables a physical immobilisation of the radiotoxical elements. In presence of MgCl2-rich salt brines, the solid waste matrice has no barrier function: the radiotoxical elements are released from the cement matrix within few months. Cs leaching behaviour shows no interaction with the cement matrix regardless of the pH in the surrounding aqueous phase. In contrast, a chemical interaction of Sr with the cement matrix can be identified for pH-value of leachant above 7. (orig.)

  5. Predicting the quality of coke based on expert evaluation of blast-furnace performance

    Energy Technology Data Exchange (ETDEWEB)

    E.N. Stepanov; A.S. Moiseenko; N.A. Tarasov; S.N. Nefedov; A.P. Verblyudenko

    2002-07-01

    The production of coke with consistent service properties is a prerequisite to stable and productive blast-furnace operation. An analysis of the available coking coals shows that changes which have taken place in coal-producing regions in recent years have led to a reduction in the mining of the most valuable industrial grades of coal - Zh, K, KO and OS. The introduction of Russian government standard GOST 25543-88 expanded the range of coals that can be used to make coke. However, it did so without consideration of the requirements that must be satisfied to produce coke good enough for use in blast-furnace smelting. Some of the grades presently designated as coking coals have properties close to those of coals used in power plant. This has had an adverse effect on the productivity of blast furnaces. The overall shortage of coal has led not only to a decrease in the total production of coke, but also to a deterioration in its service properties. Given these circumstances, the Magnitogorsk Metallurgical Combine (MMK) has attempted to keep the service properties of blast-furnace coke at as high a level as possible by devising a method to optimize the composition of the coal charge. The optimization is done by using nonlinear programming to determine the quality of the coke in relation to the properties and composition of the coal charge and the coking conditions. The optimality criterion in the model used to predict the quality of the coke is an index of mechanical strength and limits are placed on certain property indices of the components of the coal charge. 5 refs., 1 fig., 3 tabs.

  6. Investigation on Carbon-Deposition Behavior from Heating Cycle Gas in Oxygen Blast Furnace Process

    Science.gov (United States)

    Liu, Jinzhou; Wang, Jingsong; She, Xuefeng; Zhang, Shiyang; Xue, Qingguo

    2015-02-01

    Among the different ways to study carbon deposition in the ironmaking process, not much attention was paid to that of heating the gas mixture, especially cycle gas in an oxygen blast furnace. In this work, the carbon-deposition characteristics of heating 100 pct CO, CO-H2 gas mixture, and cycle gas in the oxygen blast furnace process were, respectively, experimentally and theoretically investigated. First, the thermodynamics on carbon-deposition reactions were calculated. Then, the impacts of discharging operation temperature, the proportion of CO/H2 in heating the CO-H2 gas mixture, and the CO2 concentration in heating the cycle gas of an oxygen blast furnace on the carbon deposition were tested and investigated. Furthermore, the carbon-deposition behaviors in heating the CO-H2 gas mixture were compared with the thermodynamic calculation results for discussing the role of H2. In addition, carbon deposition in heating cycle gas includes CO decomposition and a carbon-deposition reaction by hybrid of CO and H2; the possible roles of each were analyzed by comparing thermodynamic calculation and experimental results. The deposited carbon was characterized by scanning electron microscope (SEM) to analyze the deposited carbon microstructure.

  7. Interfaces Between Coke, Slag, and Metal in the Tuyere Level of a Blast Furnace

    Science.gov (United States)

    Li, Kejiang; Zhang, Jianliang; Liu, Zhengjian; Barati, Mansoor; Zhong, Jianbo; Wei, Mengfang; Wang, Guangwei; Jiao, Kexin; Yang, Tianjun

    2015-04-01

    An in-depth understanding about the reactions in the high-temperature zone of a blast furnace is significant to optimize both the current and future blast furnace process. The interfaces between coke, slag, and metal were observed using scanning electronic microscope with samples obtained from the tuyere level of a blast furnace. Two types of slag phases were identified, one originating from coke ash and the other from the bosh slag. Slag formed by coke ash was seen to cover the coke surface, which may hinder the reaction of coke with both gas and liquid iron. The reduction of FeO from the bosh slag (originated from the primary slag) occurs in the coke/slag interface with the reduced iron forming a metal layer surrounding the coke surface. The reduction of SiO2 occurs both in and outside the coke, and the reduced silicon reacts with iron to form iron silicide if the two species come into contact. Further study is proposed based on the results of this study.

  8. Volatile release and particle formation characteristics of injected pulverized coal in blast furnaces

    International Nuclear Information System (INIS)

    Volatiles release and particle formation for two kinds of pulverized coals (a high volatile bituminous coal and a low volatile bituminous coal) in a drop tube furnace are investigated to account for the reactions of pulverized coal injected in blast furnaces. Two different sizes of feed particles are considered; one is 100-200 mesh and the other is 200-325 mesh. By evaluating the R-factor, the devolatilization extent of the larger feed particles is found to be relatively poor. However, the swelling behavior of individual or two agglomerated particles is pronounced, which is conducive to gasification of the chars in blast furnaces. In contrast, for the smaller feed particles, volatiles liberated from the coal particles can be improved in a significant way as a result of the amplified R-factor. This enhancement can facilitate the performance of gas phase combustion. Nevertheless, the residual char particles are characterized by agglomeration, implying that the reaction time of the char particles will be lengthened, thereby increasing the possibility of furnace instability. Double peak distributions in char particle size are observed in some cases. This possibly results from the interaction of the plastic state and the blowing effect at the particle surface. Considering the generation of tiny aerosols composed of soot particles and tar droplets, the results indicate that their production is highly sensitive to the volatile matter and elemental oxygen contained in the coal. Comparing the reactivity of the soot to that of the unburned char, the former is always lower than the latter. Consequently, the lower is the soot formation, the better is the blast furnace stability

  9. Iron making technology with fuels and other materials injection in blast furnace tuyeres. Part 2. Pulverized coal injection (PCI)

    International Nuclear Information System (INIS)

    The technology of iron making with coal injection by tuyeres in the blast furnace is described. The influence of the main coal constituents in the furnace operation is analyzed. Information about the countries that employ this technology is given. (Author) 106 refs

  10. Productivity and performance of small scale blast furnaces; Produtividade e performance de altos fornos de pequeno porte

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Vamberto Ferreira de; Grandin, Friedrich Hans G.; Lanna, Pitagoras Gomes de; Castello Branco, Marco Antonio S.C. [Mannesmann SA, Belo Horizonte, MG (Brazil)

    1994-05-01

    This work presents some data concerning the re-start of the blast furnace number 2 of Mannesmann siderurgic company. The main characteristics concerning the operation with 100% coke fuel and the measurements adopted to increase the furnace productivity are described 2 refs., 6 figs., 5 tabs

  11. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME III. BLAST FURNACE IRONMAKING, MANUAL OF PRACTICE

    Science.gov (United States)

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  12. Computational Study of Blast Furnace Cooling Stave using Heat Transfer Analysis

    Directory of Open Access Journals (Sweden)

    Akash Shrivastava,

    2012-11-01

    Full Text Available Reliable furnace cooling technology is a domain of increasing concern to the metallurgical industry as it can significantly increase process intensities, productivity and campaign times of furnaces. Although there are many advantages in using cooling systems, they also impose a variety of problems mainly related to safety, heat losses and sustainability of the operations. The choice of cooling system is hence a matter of trade-offs and differs for every metallurgical application. This paper gives a systemic study and review of blast furnace cooling stave lining materials used in the metallurgical industries based on heat transfer analysis. Additionally, the paper describes a model which will be modeled and implemented using Pro- E modeling software. The model will further be utilized for the analysis of the behavior of lining materials at different loads through heat transfer analysis by finite element method software called ANSYS. In this study two different types of bricks like silicon carbide brick and high alumina bricks will be taken for the lining material of the blast furnace cooling stave as well as two different types of skull is considered, in which the first is having negligible thickness and the other one is having certain thickness, (thickness in mm is considered, so, with these two skulls, the heat transfer analysis will be done at different temperatures (loads from 773k to 1573k in order to compare which lining will give better results than the other.

  13. The behavior of potassium in the blast furnace deduced from isotope tracers

    International Nuclear Information System (INIS)

    Two tracer tests were done with radioactive potassium (42 K) on blast furnace no. 1, Pretoria Works. Some 80% of the injected 42 K was recovered in 2 1/2 days. About 95% of both radioactive and natural potassium reported in the slag. Mean residence times of 18 and 25 hours confirmed the accumulation of potassium in the furnace. In these tests the slag basicity appeared to be an adequate indicator of furnace conditions governing the behaviour of potassium. A quantitative discontinious model with varying volume CSTR's and interflow controlled according to slag basicity - could be made to fit the results of both tests. The total amounts of K2O required by the model - 4 and 9 t respectively - were larger than estimates from input/output imbalance, or from mean residence time of the tracer

  14. Model of the ore-to-coke distribution in the blast furnace shaft

    Energy Technology Data Exchange (ETDEWEB)

    Nikus, M.J.; Saxen, H. [Aabo Akademi University, Aabo (Finland). Heat Engineering Lab.

    2002-07-01

    In this paper, an approach to estimate the burden distribution on-line in the blast furnace is briefly outlined. The method is mainly based on temperature measurements from an above-burden probe in combination with a simplified static model of the conditions in the upper part of the furnace, which together yield a picture of the burden distribution. Similar methods, but using a different set of measurements have been reported by other investigators. The method proposed in this paper is tested on data logged at the BF2 of SSAB in Luleaa, Sweden. The results of the model were found to be in general agreement with layer thickness estimates from a profile meter at the furnace. 21 refs., 7 figs., 1 tab.

  15. Oxygen blast furnace and combined cycle (OBF-CC) - an efficient iron-making and power generation process

    International Nuclear Information System (INIS)

    A new iron and power generating process, oxygen blast furnace and combined cycle (OBF-CC), is presented. In order to support the opinion, the features of the oxygen blast furnace and integrated coal gasification and combined cycle (IGCC) are summarized. The relation between the blasting parameters and the output gas quantity, as well as caloric value is calculated based on mass and energy balance. Analysis and calculation indicate that the OBF-CC will be an efficient iron-making and power generation process with higher energy efficiency and less pollution

  16. Changes in the microstructure of coke while passing the blast furnace with respect to the quality of the charged coke and the behaviour of nut coke in the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Janhsen, U.; Guenbati, A.; Sautner, C. (and others) [ThyssenKrupp Steel, Duisburg (Germany)

    2007-07-01

    This study provides a comprehensive contribution to the understanding of the metallurgical stresses to which the coke is exposed in a blast furnace. The investigations refer to the change in the coke microstructure depending on the charged feed coke quality and the blast furnace operatic conditions. Also the behaviour of nut coke (coke - 35 mm) in the blast furnace is determined. To work on the scheduled activities and aims of the project various tools are used by the different partners. At TKS, a new microscopic measurement method quantifying the change in the coke carbon micro texture is used to compare the microstructure of feed coke, CRI/CSR treated coke and core drilled coke from the tuyere level of different TKS blast furnaces. Tuyere core drill exercises also are used to detect ZrO{sub 2} traced nut coke charged as mix with burden components in the lower part of the furnace, CSM used the MOSCA model and tuyere core drillings to investigate the behaviour of the nut at a blast furnace of Lucchini at Piombino (Italy). At MEFOS, cokes excavated from LKAB's Experimental Blast Furance (EBF) are used as a basis for the research. The evolution of the EBF coke properties, particuly the carbon structure and alkali uptake were related to CO{sub 2} reactivity. At DMT synthetic coke materials of various qualites are produced for laboratory investigations also at the partner. The University of Aachen RWTH studies the behaviour of coke under various blast furnace scenarios to detect also the changes in the coke microstructure. 12 refs., 141 figs., 63 tabs.

  17. Thermal analysis evaluation of the reactivity of coal mixtures for injection in the blast furnace

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Ilha Gomes

    2006-03-01

    Full Text Available Pulverized Coal Injection (PCI is an important standard technology replacing coke partially by pulverized coal into the blast furnace that allows a significant reduction of hot metal costs and environmental impact, contributing to a decrease of coke requirements for ironmaking. Coals typically used in this process in Brazil are, at current time, exclusively imported from many countries, although economic important coal-measures occur in the southern part of the country. The Brazilian coals have a low rank, higher contents of inert components, proportioning nocoking properties and an expected high reactivity. Due to these caractheristics, these coals could be used for injection in the blast furnaces in order to decrease the dependency on high cost imported coals. The efficiency in the combustion and the coal reactivity are considered important parameters in the blast furnace, since a larger amount of char (unburned coal causes severe problems to the furnace operation. The aim of the present work is to compare the reactivity of a south Brazilian coal, obtained from Faxinal mine, with two imported coals and the blends of the Brazilian coal with the imported ones. The reactivity of these coals and their blends were evaluated in a thermogravimetric analyzer. In the experiments, various mass ratios of Faxinal coal and the imported coals were used to compose the blends. The gasification reaction with pure CO2 was conducted under isothermal conditions at 1050 °C and atmospheric pressure. The experimental results show the greater reactivity of the Faxinal coal. The additive behavior was confirmed. The blends with a composition of up to 50% Faxinal coal have parameters according to the usual limits used for PCI.

  18. Thermal analysis evaluation of the reactivity of coal mixtures for injection in the blast furnace

    Scientific Electronic Library Online (English)

    Maria de Lourdes Ilha, Gomes; Eduardo, Osório; Antônio Cezar Faria, Vilela.

    2006-03-01

    Full Text Available Pulverized Coal Injection (PCI) is an important standard technology replacing coke partially by pulverized coal into the blast furnace that allows a significant reduction of hot metal costs and environmental impact, contributing to a decrease of coke requirements for ironmaking. Coals typically used [...] in this process in Brazil are, at current time, exclusively imported from many countries, although economic important coal-measures occur in the southern part of the country. The Brazilian coals have a low rank, higher contents of inert components, proportioning nocoking properties and an expected high reactivity. Due to these caractheristics, these coals could be used for injection in the blast furnaces in order to decrease the dependency on high cost imported coals. The efficiency in the combustion and the coal reactivity are considered important parameters in the blast furnace, since a larger amount of char (unburned coal) causes severe problems to the furnace operation. The aim of the present work is to compare the reactivity of a south Brazilian coal, obtained from Faxinal mine, with two imported coals and the blends of the Brazilian coal with the imported ones. The reactivity of these coals and their blends were evaluated in a thermogravimetric analyzer. In the experiments, various mass ratios of Faxinal coal and the imported coals were used to compose the blends. The gasification reaction with pure CO2 was conducted under isothermal conditions at 1050 °C and atmospheric pressure. The experimental results show the greater reactivity of the Faxinal coal. The additive behavior was confirmed. The blends with a composition of up to 50% Faxinal coal have parameters according to the usual limits used for PCI.

  19. Biomass as blast furnace injectant – Considering availability, pretreatment and deployment in the Swedish steel industry

    International Nuclear Information System (INIS)

    Highlights: • Injection of biofuels was modeled, using real blast furnace data as reference. • For charcoal, torrefied and pelletized biomass; a replacement limit was predicted. • As expected, reduced CO2 emissions are possible, especially when using charcoal. • We also found that substantial energy savings can be made, using any of the biofuels. • Circumstances today and biomass availability tomorrow are encouraging for deployment. - Abstract: We have investigated and modeled the injection of biomass into blast furnaces (BF), in place of pulverized coal (PC) from fossil sources. This is the easiest way to reduce CO2 emissions, beyond efficiency-improvements. The considered biomass is either pelletized, torrefied or pyrolyzed. It gives us three cases where we have calculated the maximum replacement ratio for each. It was found that charcoal from pyrolysis can fully replace PC, while torrefied material and pelletized wood can replace 22.8% and 20.0% respectively, by weight. Our energy and mass balance model (MASMOD), with metallurgical sub-models for each zone, further indicates that (1) more Blast Furnace Gas (BFG) will be generated resulting in reduced fuel consumption in an integrated plant, (2) lower need of limestone can be expected, (3) lower amount of generated slag as well, and (4) reduced fuel consumption for heating the hot blast is anticipated. Overall, substantial energy savings are possible, which is one of the main findings in this paper. Due to the high usage of PC in Sweden, large amounts of biomass is required if full substitution by charcoal is pursued (6.19 TWh/y). But according to our study, it is likely available in the long term for the blast furnace designated M3 (located in Luleå). Finally, over a year with almost fully used production capacity (2008 used as reference), a 28.1% reduction in on-site emissions is possible by using charcoal. Torrefied material and wood pellets can reduce the emissions by 6.4% and 5.7% respectively. The complete replacement of PC in BF M3 can reduce 17.3% of the total emissions from the Swedish steel industry

  20. Volatilization of elemental mercury from fresh blast furnace sludge mixed with basic oxygen furnace sludge under different temperatures.

    Science.gov (United States)

    Földi, Corinna; Dohrmann, Reiner; Mansfeldt, Tim

    2015-11-01

    Blast furnace sludge (BFS) is a waste with elevated mercury (Hg) content due to enrichment during the production process of pig iron. To investigate the volatilization potential of Hg, fresh samples of BFS mixed with basic oxygen furnace sludge (BOFS; a residue of gas purification from steel making, processed simultaneously in the cleaning devices of BFS and hence mixed with BFS) were studied in sealed column experiments at different temperatures (15, 25, and 35 °C) for four weeks (total Hg: 0.178 mg kg(-1)). The systems were regularly flushed with ambient air (every 24 h for the first 100 h, followed by every 72 h) for 20 min at a flow rate of 0.25 ± 0.03 L min(-1) and elemental Hg vapor was trapped on gold coated sand. Volatilization was 0.276 ± 0.065 ng (x m: 0.284 ng) at 15 °C, 5.55 ± 2.83 ng (x m: 5.09 ng) at 25 °C, and 2.37 ± 0.514 ng (x m: 2.34 ng) at 35 °C. Surprisingly, Hg fluxes were lower at 35 than 25 °C. For all temperature variants, an elevated Hg flux was observed within the first 100 h followed by a decrease of volatilization thereafter. However, the background level of ambient air was not achieved at the end of the experiments indicating that BFS mixed with BOFS still possessed Hg volatilization potential. PMID:26444147

  1. Numerical Study of the Gas Distribution in an Oxygen Blast Furnace. Part 2: Effects of the Design and Operating Parameters

    Science.gov (United States)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2015-09-01

    Gas distribution plays a significant role in an oxygen blast furnace. The uneven distribution of recycling gas from the shaft tuyere has been shown to affect the heat distribution and energy utilization in an oxygen blast furnace. Therefore, the optimal design and operating parameters beneficial to the gas distribution in an oxygen blast furnace should be determined. In total, three parameters and 22 different conditions in an oxygen blast furnace multifluid model were considered. The gas and heat distributions in an oxygen blast furnace under different conditions were simulated and compared. The study revealed that when the height of shaft tuyere decreased from 7.8 m to 3.8 m, the difference in top gas CO concentration between the center and edge decreased by 11.6%. When the recycling gas temperature increased from 1123 K to 1473 K, the difference in the top gas CO concentration between the center and edge decreased by 3.9%. As the allocation ratio increased from 0.90 to 1.94, the difference in the top gas CO concentration between the center and edge decreased by 3.0%. Considering both gas and heat distributions, a shaft tuyere height of 3.8 m to 4.8 m, a recycling gas temperature of 1473 K and an allocation ratio of 1.94 are recommended in practice under the conditions of this study.

  2. Simultaneous utilization of neutrons and ?-rays from 252Cf for condition measurement inside a blast furnace

    International Nuclear Information System (INIS)

    This paper describes the possibility of the realization of a multi-function radiation gauge to meet the requirement for more precise and stable control of a blast furnace. A basic concept of the gauge is to measure some quantities with simultaneous use of multi-radiations of neutrons and ?-rays, and to obtain multi-types of information on material flow and gas flow representing the conditions inside the blast furnace. The prototype gauge was assembled and examined which consisted of a radiation source of 252Cf (3.7 MBq), neutron moderator, lead shield, a bismuth germanate detector, stainless casing and a control unit. Laboratory experiments showed that the gauge could measure the quantities to be essential to estimate the blast furnace conditions. In practice, it clearly distinguished between iron ore and coke layers, and at the same time measured bulk density (1.0-1.5 g/cm3) of iron contained in iron ore by counting thermal neutron capture ?-rays (6.5-8.5 MeV) from iron. It also gave the information on material bulk density (0.5-2.5 g/cm3) by detecting Compton scattered ?-rays (1.0-1.5 MeV) from material, i.e. iron ore and coke. The relative accuracies in the measurement of iron bulk density and material bulk density were estimated to be within 1 and 4% in 300 s counting time, respectively. The possibility of the gauge has been proved and the on-line trial will be expected in the near future. (author)

  3. Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) into the Blast Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Chenn Zhou

    2008-10-15

    Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.

  4. Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) to Blast Furnaces

    International Nuclear Information System (INIS)

    Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process

  5. Effect of recycling blast furnace flue dust as pellets on the sintering performance

    OpenAIRE

    El-Hussiny N.A.; Shalabi M.E.H.

    2010-01-01

    The Egyptian Iron and Steel Company generates a great amount of blast furnace flue dust. The recovery of metals and carbon from this flue dust becomes a very important demand due to the increase of the price of coke breeze and the decrease of the primary source of metals. At the same time, it make the environment more safe by decreasing pollution. Introducing these dust fines in the sintering process proves to be very harmful for different operating parameters. Thus, this study aims at ...

  6. Drying shrinkage of mortars with limestone filler and blast-furnace slag

    Directory of Open Access Journals (Sweden)

    Carrasco, M. F.

    2003-12-01

    Full Text Available During the 1990's the use of cements made with port land clinker and two mineral admixtures, called ternary or blended cements, has grown considerably. Nowadays, cements containing several combinations of fly ash and silica fume, blast-furnace slag and silica fume or blast-furnace slag and limestone filler are commonly used. There are numerous works on the influence of blended cements on the fresh state and mechanical properties of mortar and concrete, but the their deformations due to drying shrinkage are not so well described. Analysis of drying shrinkage is relevant because this property influences the possibility of cracking occurrence and, hence, the deterioration of mechanical and durable properties of concrete structures. This paper evaluates the influence on the drying shrinkage of mortars of variable contents of limestone filler and/or blast-furnace slag in Portland cement. Additionally, flexion strength and non evaporable water content were evaluated. Test results show that the inclusion of these mineral admixtures, Joint or separately, increments drying shrinkage of mortars at early ages. Despite this fact, mortars made with limestone filler cement are less susceptible to cracking than mortars made with cements incorporating blast-furnace slag or both admixtures.

    Durante los años 90 el uso de cementos fabricados con clínker Portland y dos adiciones suplementarias (cementos ternarios o compuestos se ha incrementado en forma considerable. En la práctica, es cada vez más común el empleo de estos cementos conteniendo combinaciones de ceniza volante y humo de sílice, escoria y humo de sílice o escoria y filler calcáreo. En la actualidad existen numerosos estudios sobre la influencia de los cementos compuestos en las características en estado fresco y las propiedades mecánicas de morteros y hormigones, pero las deformaciones que estos materiales sufren debido a la retracción por secado no son tan conocidas. El análisis de la retracción por secado resulta un tema relevante, pues este parámetro determina la posibilidad de fisuración, y consecuentemente el deterioro de las propiedades mecánicas y durables de las estructuras. En el presente trabajo se estudia la influencia que tiene la inclusión de contenidos variables de filler calcáreo y/o escoria granulada de alto horno al cemento portland sobre la retracción por secado de los morteros elaborados con ellos. Adicional mente se ha analizado la resistencia a flexión y el contenido de agua no evaporable. Los resultados obtenidos indican que la inclusión en forma conjunta o separada de estas adiciones incrementa la retracción inicial del mortero. Aun así, los morteros con filler calcáreo presentan una menor tendencia a la fisuración que los cementos con escoria o filler y escoria.

  7. Fast neutron (14 MeV) activation analysis of fluorine in blast furnace slags

    International Nuclear Information System (INIS)

    The paper presents an application of the neutron activation analysis (NAA) for estimating the content of fluorine in blast furnace slag. The samples were irradiated for 200 sec. in a maximum neutron field of 1010 n/sec. Fluorine was detected by observing the 197 KeV gamma rays (T1/2 = 26.9 sec) following the 19 F(n,p)19 O reaction. The fluorine content was deduced by relating to standard (CaF2) samples measured in identical irradiation-measuring conditions. A maximum fluorine content of 3% was observed in our investigated samples. (Author)

  8. Mathematical model of burden distribution for the bell-less top of a blast furnace

    Science.gov (United States)

    Teng, Zhao-jie; Cheng, Shu-sen; Du, Peng-yu; Guo, Xi-bin

    2013-07-01

    Due to the difficulty in measuring the burden trajectory directly in an actual blast furnace (BF), a mathematical model with Coriolis force and gas drag force considered was developed to predict it. The falling point and width of the burden flow were obtained and analyzed by the model, the velocities of particles at the chute end were compared with and without the existence of Coriolis force, and the effects of chute length and chute torque on the falling point were also discussed. The simulation results are in good agreement with practical measurements with laser beams in a 2500 m3 BF.

  9. Application of X-ray pulse analyzer for determining level and profile of blast furnace charge

    International Nuclear Information System (INIS)

    The X-ray pulse analyzer for determining the level and profile of blast furnace charge 'TAIR' is developed. It is based on the time-pulse method of measurement and it includes a scanning X-ray generator, a primary converter, a detector, a data processing and representation unit, a control unit for scanning. The analyzer is tested at Magnitogorsk integrated iron-and-steel works under statical and dynamical conditions. Applicability of the X-ray pulse analyzer as an engineering device to control the process and conduction of investigations is shown

  10. Effect of alkaline elements on the reactivity, strength and structural properties of blast furnace cokes

    Directory of Open Access Journals (Sweden)

    A. Bhattacharyya

    2015-07-01

    Full Text Available The present study concerns itself on the adverse effects of alkaline elements like sodium and potassium on blast furnace cokes. To achieve a deeper insight on the effects of alkaline elements on coke reactivity and strength, industrial coke samples impregnated with different alkaline species in various amounts have been tested under standard conditions to find out their Coke Reactivity Index (CRI and Coke Strength after Reaction (CSR values. Scanning electron microscopy, petrographic and Raman Spectrometric investigations demonstrate the change of structural properties. The mechanism of catalysis has been postulated.

  11. Soot formation in a blast furnace - Prediction via a parametric study, using detailed kinetic modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nordstroem, T.; Kilpinen, P.; Hupa, M. [Aabo Akademi, Turku (Finland). Combustion Chemistry Group

    1996-12-31

    The objective of this work has been to investigate the soot formation in a blast furnace fired with heavy fuel oil, using detailed kinetic modelling. This work has been concentrated on parameter studies that could explain under which conditions soot is formed and how that formation could be avoided. The parameters investigated were temperature, pressure, stoichiometric ratio, pyrolysis gas composition and reactor model. The calculations were based on a reaction mechanism that consists of 100 species and 446 reactions including polyaromatic hydrocarbons (PAM) up to 7 aromatic rings SULA 2 Research Programme; 4 refs.

  12. Novel Recognition Method of Blast Furnace Dust Composition by Multifeature Analysis Based on Comprehensive Image-Processing Techniques

    Science.gov (United States)

    Guo, Hongwei; Su, Buxin; Bai, Zhenlong; Zhang, Jianliang; Li, Xinyu

    2014-11-01

    The traditional artificial recognition methods for the blast furnace dust composition have several disadvantages, including a great deal of information to dispose, complex operation, and low working efficiency. In this article, a multifeature analysis method based on comprehensive image-processing techniques was proposed to automatically recognize the blast furnace dust composition. First, the artificial recognition and feature analysis, which included image preprocessing, Harris corner feature, Canny edge feature, and Ruffle feature analysis, was designed to build the template image, so that any unknown dust digital image could be tested. Second, the composition of coke, microvariation pulverized coal, vitric, ash, and iron from dust would be distinguished according to their different range of values based on the multifeature analysis. The method is valid for recognizing the blast furnace dust composition automatically, and it is fast and has a high recognition accuracy.

  13. Choice of technological regimes of a blast furnace operation with injection of hot reducing gases

    Directory of Open Access Journals (Sweden)

    Babich, A. I.

    2002-08-01

    Full Text Available Injection rate of fossil fuels is limited because of drop in the flame temperature in the raceway and problems in the deadman region and the cohesive zone. The next step for obtaining a considerable coke saving, a better operation in the deadman as an well as increase in blast furnace productivity and minimizing the environmental impact due to a decrease in carbon dioxide emmision would be injection by tuyeres of hot reducing gases (HRG which are produced by low grade coal gasification or top gas regenerating. Use of HRG in combination with high pulverized coal inyection PCI rate and oxigen enrichment in the blast could allow to keep and to increase the competitiveness of the blast furnace process. Calculations using a mathematical model show that the HRG injection in combination with pulverized coal (PC and enriching blast with oxigen can provide an increase in PC rate up to 300-400 kg/tHM and a rise in the furnace productivity by 40-50 %. Blast furnace operation with full oxigen blast (100 % of process oxigen with the exception for the hot blast is possible when HRG is injected.

    La tasa de inyección de combustibles fósiles está limitada a causa de la caída de la temperatura de llama en el raceway (cavidad frente a las toberas y a problemas en la región del "hombre muerto" y en la zona cohesiva. La inyección por tobera de gases reductores calientes (GRC, que se producen por gasificación de carbón de bajo grado o generación de gas de tragante, será la próxima etapa para lograr un considerable ahorro adicional de coque, una zona del "hombre muerto" bien definida, además de un aumento en la productividad del horno alto y para minimizar el impacto ambiental debido a una disminución de la emisión de dióxido de carbono. El uso de GRC en combinación con una tasa elevada de inyección de carbón pulverizado (ICP con viento enriquecido en oxígeno, podrá permitir mantener y aumentar la competitividad del proceso del horno alto. Los cálculos, utilizando un modelo matemático, muestran que la inyección de GRC en combinación con la ICP y enriquecimiento del viento con oxígeno pueden suministrar un aumento en la tasa de carbón pulverizado hasta 300-400 kg/t arrabio y una elevación en la productividad del horno de 40-50 %. La operación del horno alto con un máximo de oxígeno en el viento (100 % del oxígeno del proceso con la excepción para el viento caliente es posible cuando se inyecta GRC.

  14. Statistical analysis of the blast furnace process output parameter using arima control chart with proposed methodology of control limits setting

    Directory of Open Access Journals (Sweden)

    D. Noskievi?ová

    2009-10-01

    Full Text Available The paper deals with the statistical analysis of the selected parameter of the blast furnace process. It was proved that analyzed measurements have been autocorrelated. ARIMA control chart was selected for their analysis as a very useful statistical process control (SPC method. At first the methodology for control limits setting in ARIMA control charts considering the time series outlier analysis as an integral part of the ARIMA model building was designed. Then this proposal was applied to the statistical analysis of the selected blast furnace process output parameter with the aim to compare two production methods.

  15. Process Simulation and Control Optimization of a Blast Furnace Using Classical Thermodynamics Combined to a Direct Search Algorithm

    Science.gov (United States)

    Harvey, Jean-Philippe; Gheribi, Aïmen E.

    2013-12-01

    Several numerical approaches have been proposed in the literature to simulate the behavior of modern blast furnaces: finite volume methods, data-mining models, heat and mass balance models, and classical thermodynamic simulations. Despite this, there is actually no efficient method for evaluating quickly optimal operating parameters of a blast furnace as a function of the iron ore composition, which takes into account all potential chemical reactions that could occur in the system. In the current study, we propose a global simulation strategy of a blast furnace, the 5-unit process simulation. It is based on classical thermodynamic calculations coupled to a direct search algorithm to optimize process parameters. These parameters include the minimum required metallurgical coke consumption as well as the optimal blast chemical composition and the total charge that simultaneously satisfy the overall heat and mass balances of the system. Moreover, a Gibbs free energy function for metallurgical coke is parameterized in the current study and used to fine-tune the simulation of the blast furnace. Optimal operating conditions and predicted output stream properties calculated by the proposed thermodynamic simulation strategy are compared with reference data found in the literature and have proven the validity and high precision of this simulation.

  16. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia.

    Science.gov (United States)

    Mohiuddin, Kazi; Strezov, Vladimir; Nelson, Peter F; Stelcer, Eduard; Evans, Tim

    2014-07-15

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 ?m. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings. PMID:24793329

  17. Mechanical and cementitious characteristics of ground granulated blast furnace slag and basic oxygen furnace slag blended mortar

    International Nuclear Information System (INIS)

    Highlights: • This is an innovative cementitious material. • The cementitious of this study which mixed some steel slag and iron slag. • The mechanical properties of the new cementitious is like traditional cement. - Abstract: Reusing waste materials and reducing carbon emissions are crucial environmental concerns. Ground granulated basic oxygen furnace slag (GGBOS) and ground granulated blast furnace slag (GGBS) are the by-products of the steel industry and has positive effects on the environment because it reduces the problems associated waste disposal. This study reused these two products to completely replace cementitious materials, thus contributing to waste recycling, reducing the production demand for cement, and mitigating carbon emissions. Twelve mixture proportions were designed in this study, including an ordinary Portland mortar (OPM) as the control group and 11 steel/iron slag blended mortar (SISBM) experimental groups for the mechanical and cementitious characteristic experiments. The optimal mixing ratio for SISBM compressive strength ranged from GGBOS (steel slag): GGBS (iron slag) = 3:7 to 5:5 (by weight). At the age of 91 days, the compressive strength of SISBM reached 80–90% compared with that of the control group. Based on the pH values, free-CaO, and microanalysis results, the cementitious characteristics were mainly generated because the GGBOS increased the free-CaO or Ca(OH)2 concentrations in the SISBM curing water and provided alkaline environments for Ca(OH)2 to engage in the pozzolanic reaction with the SiO2 and Al2O3 in GGBS, forming crystals such as calcium aluminum silicate hydrate, (C–A–S–H), calcium silicate hydrate (C–S–H), and calcium–magnesium–alumina–silicate (C–M–A–S), which generated strength and strengthened microstructure

  18. Application of surface contour gamma radar in automatic system for control burden surface state at a blast furnace top

    International Nuclear Information System (INIS)

    Description and results of testing a quick-acting gamma radar, designed for rapid control of burden surface state on a blast furnace top, are presented. Tests showed that the radar enables to obtain rapidly important information about the character of burden material descent and peculiarities of technological process on the furnace top. Recommendations on effective application of the gamma radar in automatic control system are given

  19. Discrete element simulation of charging and mixed layer formation in the ironmaking blast furnace

    Science.gov (United States)

    Mitra, Tamoghna; Saxén, Henrik

    2015-11-01

    The burden distribution in the ironmaking blast furnace plays an important role for the operation as it affects the gas flow distribution, heat and mass transfer, and chemical reactions in the shaft. This work studies certain aspects of burden distribution by small-scale experiments and numerical simulation by the discrete element method (DEM). Particular attention is focused on the complex layer-formation process and the problems associated with estimating the burden layer distribution by burden profile measurements. The formation of mixed layers is studied, and a computational method for estimating the extent of the mixed layer, as well as its voidage, is proposed and applied on the results of the DEM simulations. In studying a charging program and its resulting burden distribution, the mixed layers of coke and pellets were found to show lower voidage than the individual burden layers. The dynamic evolution of the mixed layer during the charging process is also analyzed. The results of the study can be used to gain deeper insight into the complex charging process of the blast furnace, which is useful in the design of new charging programs and for mathematical models that do not consider the full behavior of the particles in the burden layers.

  20. Blast furnace slag-cement grout blends for the immobilization of technetium-containing wastes

    International Nuclear Information System (INIS)

    Mixed low-level radioactive and chemically toxic process treatment wastes from the Portsmouth Gaseous Diffusion Plant are stabilized by solidification in cement-based grouts. Conventional portland cement and fly ash grouts are shown to be very effective for retention of hydrolyzable heavy metals (including lead, cadmium, uranium, and nickel), but are marginally acceptable for retention of radioactive 99Tc (which is present in the waste as the highly mobile pertechnate anion). Addition of ground blast furnace slag to the grout is shown to reduce the effective diffusivity of technetium by several orders of magnitude; retention of technetium is improved by decreasing the waste loading in the grout or by increasing the proportion of blast furnace slag in the grout dry mix. The selective effect of slag is believed to be due to its ability to reduce Tc(VIII) to the less soluble Tc(IV) species. The addition of other reductive grout admixtures (e.g., sodium sulfide, ferrous ion, and powdered iron metal) also appear to improve the retention of technetium in grout. 31 refs., 2 figs., 25 tabs

  1. Improved CFD Model to Predict Flow and Temperature Distributions in a Blast Furnace Hearth

    Science.gov (United States)

    Komiyama, Keisuke M.; Guo, Bao-Yu; Zughbi, Habib; Zulli, Paul; Yu, Ai-Bing

    2014-10-01

    The campaign life of a blast furnace is limited by the erosion of hearth refractories. Flow and temperature distributions of the liquid iron have a significant influence on the erosion mechanism. In this work, an improved three-dimensional computational fluid dynamics model is developed to simulate the flow and heat transfer phenomena in the hearth of BlueScope's Port Kembla No. 5 Blast Furnace. Model improvements feature more justified input parameters in turbulence modeling, buoyancy modeling, wall boundary conditions, material properties, and modeling of the solidification of iron. The model is validated by comparing the calculated temperatures with the thermocouple data available, where agreements are established within ±3 pct. The flow distribution in the hearth is discussed for intact and eroded hearth profiles, for sitting and floating coke bed states. It is shown that natural convection affects the flow in several ways: for example, the formation of (a) stagnant zones preventing hearth bottom from eroding or (b) the downward jetting of molten liquid promoting side wall erosion, or (c) at times, a vortex-like peripheral flow, promoting the "elephant foot" type erosion. A significant influence of coke bed permeability on the macroscopic flow pattern and the refractory temperature is observed.

  2. Model of Draining of the Blast Furnace Hearth with an Impermeable Zone

    Science.gov (United States)

    Saxén, Henrik

    2015-02-01

    Due to demands of lower costs and higher productivity in the steel industry, the volume of operating blast furnaces has grown during the last decades. As the height is limited by the allowable pressure drop, the hearth diameter has grown considerably and, along with this, also draining-related problems. In this paper a mathematical model is developed for simulating the drainage in the case where an impermeable region exists in the blast furnace hearth. The model describes the quasi-stationary drainage process of a hearth with two operating tapholes, where the communication between the two pools of molten slag and iron can be controlled by parameterized expressions. The model also considers the case where the buoyancy of the liquids is sufficient for lifting the coke bed. The implications of different size of the liquid pools, communication between the pools, bed porosity, etc. are studied by simulation, and conclusions concerning their effect on the drainage behavior and evolution of the liquid levels in the hearth are drawn. The simulated liquid levels are finally demonstrated to give rise to a pressure profile acting on the hearth which agrees qualitatively with signals from strain gauges mounted in the hearth wall of an industrial ironmaking process.

  3. Properties and application of carbon composite brick for blast furnace hearth

    Directory of Open Access Journals (Sweden)

    Jiao K.X.

    2015-01-01

    Full Text Available A type of carbon composite brick was produced via the microporous technique using natural flack graphite, ?-Al2O3 and high-quality bauxite chamotte (Al2O3?87 mass% as raw materials with fine silicon powder as additive. The composition and microstructure of the obtained carbon composite were characterized using chemical analysis, XRD and SEM with EDS. The high temperature properties of thermal conductivity, oxidization and corrosion by molten slag and hot metal of the composite were analyzed. Based on these, the type of carbon composite brick worked in a blast furnace hearth for six years was further sampled at different positions. The protective layer was found and its chemical composition and microscopic morphology were investigated. It is found that the carbon composite brick combines the good properties of both the conventional carbon block and ceramic cup refractory. The protective layer near the hot face consists of two separated sublayers, i.e. the slag layer and the carbon layer. A certain amount of slag phase is contained in the carbon layer, which is caused by the reaction of coke ash with the refractory. No obvious change in the chemical composition of the protective layer along the depth of the sidewall is found. This work provides a useful guidance for the extension of the lifetime of blast furnace hearths.

  4. High temperature properties of by-product cold bonded pellets containing blast furnace flue dust

    International Nuclear Information System (INIS)

    In this investigation, the fundamental reactions occurring during the heat treatment of cold bonded pellets (CBP) comprised of iron and steelmaking by-products have been studied. Blast furnace (BF) flue dust, which contains fractions of coal and coke particles, has been included in the CBP blend as a source of solid reductant. Thermal analysis was performed on CBP samples in inert atmosphere at a heating rate of 10 deg C/min in order to observe their high temperature properties, specifically, the mechanisms of self-reduction within CBPs. Both endothermic and exothermic reactions were observed during heating. The gases generated during thermal analysis were analyzed using a quadropole mass spectrometer (QMS). Furthermore, CBP samples heated to several different temperatures and quenched in argon were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results from this investigation demonstrate that the decomposition of hydrates and carbonates in CBP samples contribute, as gaseous intermediates, to an earlier reduction of contained iron oxides. The gaseous intermediates are responsible for an initial gasification of carbon contained in blast furnace flue dust leading to low temperature iron oxide reduction. The step-wise reduction of iron oxides in CBPs at the given conditions begins at ?500 deg C and is nearly completed at 1200 deg C. This work can help to provide a fundamental understanding of the reduction characteristics of iron and steelmaking by-product agglomerates

  5. Application of Granulated Blast Furnace Slag in Cement Composites Exposed to Biogenic Acid Attack

    Science.gov (United States)

    Kovalcikova, M.; Estokova, A.; Luptakova, A.

    2015-11-01

    The deterioration of cement-based materials used for the civil infrastructure has led to the realization that cement-based materials, such as concrete, must be improved in terms of their properties and durability. Leaching of calcium ions increases the porosity of cement- based materials, consequently resulting in a negative effect on durability since it provides an entry for aggressive harmful ions, causing corrosion of concrete. The use supplementary cementing composite materials have been reported to improve the resistance of concrete to deterioration by aggressive chemicals. The paper is focused on the investigation of the influence of biogenic acid attack on the cement composites affected by bacteria Acidithiobacillus thiooxidans. The concrete specimens with 65 wt. % addition of antimicrobial activated granulated blast furnace slag as durability increasing factor as well as without any addition were studied. The experiments proceeded during 150 days under model laboratory conditions. The pH values and chemical composition of leachates were measured after each 30- day cycle. The calcium and silicon contents in leachates were evaluated using X - ray fluorescence method (XRF). Summarizing the results, the 65% wt. addition of antimicrobial activated granulated blast furnace slag was not confirmed to be more resistant.

  6. Fixation of CO2 by carbonating calcium derived from blast furnace slag

    International Nuclear Information System (INIS)

    Industrial waste materials, such as steelmaking slags, appear to be potential raw materials for reducing CO2 emissions by carbonation. The suitability of applying a carbonation route based on acetic acid leaching to produce carbonates from blast furnace slag is presented in this study. The effect of solution pH, temperature, and CO2 pressure on the precipitation of carbonates was experimentally studied. A simple thermodynamic model was used to verify our results. The feasibility of the process was also discussed, addressing energy input requirements and the consumption of chemicals. According to our experiments, the addition of NaOH, i.e. an increase in solution pH, is required for the adequate precipitation of calcium carbonate at temperatures of 30-70 deg. C and pressures of 1 or 30 bar. Preliminary process calculations showed that approximately 4.4 kg of blast furnace slag, 3.6 l of acetic acid, and 3.5 kg of NaOH would be required to bind 1 kg of CO2, resulting in 2.5 kg of 90% calcium carbonate. While the heat needed for the evaporation of the acetic acid could probably be acquired as waste heat by process integration with other processes, the electricity required for NaOH regeneration would make the process unsuitable for CO2 sequestration

  7. A Novel Technique for Making Cold Briquettes for Charging in Blast Furnace

    Science.gov (United States)

    Mohanty, M. K.; Mishra, S.; Mishra, B.; Sarkar, S.; Samal, S. K.

    2016-02-01

    Different metallurgical wastes are generated during pyro processing of iron ore, which is used for making sponge iron or hot metal and for producing steel. Apart from these wastes, coke fines are generated during the coke making, and iron ore fines are generated during mining of iron ore. Although iron ore fines are used for making pellet after beneficiation still, it generates a huge quantity of iron ore waste during beneficiation with comparatively lower iron content. In the present study, briquettes are made by a stiff extrusion process from metallurgical waste like iron ore fines and coke fines with the addition of Portland cement as a binder and clay as a rheology modifier. Physical properties of the briquettes are evaluated, and reducibility of the briquettes is studied in comparison to lumpy iron ore. Phase analysis and microstructural analysis of the briquettes and lumpy iron ore are carried out after firing at different temperatures in the simulated blast furnace condition. Physical and mineralogical properties are correlated with the reducibility of the briquettes and lumpy iron ore. Briquettes made by a stiff extrusion process show a better mechanical strength fired at a different temperature to take the load of burden and better reducibility than lumpy iron ore. The briquettes after self-curing are charged to a 23 mt3 blast furnace which shows encouraging results.

  8. A new concept of auxiliary fuel injection through tuyeres in blast furnaces developed by numerical simulations

    Directory of Open Access Journals (Sweden)

    Bruno Orlando de Almeida Santos

    2014-04-01

    Full Text Available The Injection of powdered materials in blast furnaces is a great option for reducing costs, increasing productivity and satisfy the environmental norms. Thus, this paper presents a study on the use of a flame stabilization system with rotation, designed to promote greater coal injection in the combustion zone, reducing losses and increasing the efficiency of the equipment. A physical model was used to evaluate scattering of pulverized fuel and is compared with numerical results in the same scale. In the second step, a combustion model was added to the numerical simulation, using dimensions of a real blast furnace. Fields like temperature, velocity and behavior of chemical reactions were analyzed. The results showed that double lances promote better particle injection when compared with simple lance for reduced material injection. The new injection system proposed, with swirl numbers of 0.12 and 0.24, promoted a better injection of both reduced material and temperature in the raceway zone. The swirl 0.24 showed superior performance when compared to other injection systems.

  9. Nonfibrous mineralogical analysis of bronchoalveolar lavage fluid from blast-furnace workers.

    Science.gov (United States)

    Corhay, J L; Bury, T; Delavignette, J P; Baharloo, F; Radermecker, M; Hereng, P; Fransolet, A M; Weber, G; Roelandts, I

    1995-01-01

    Steelworkers are exposed to many pollutants, and they are at risk for developing lung cancer. We demonstrated previously that steelworkers may be subject to an occult exposure to amphiboles in the plant environment. In the current study, we further analyzed bronchoalveolar lavage fluid of steelworkers by measuring intramacrophagic trace-metal content and nonfibrous mineral particles, using the particle-induced x-ray emission method and electron microscopy, respectively. Forty-seven blast-furnace workers and 45 healthy white-collar workers volunteered for this study. Significantly increased levels of iron, titanium, zinc, and bromine were found in the steelworkers, and levels of lead, chromium, arsenic, and strontium tended to increase in the macrophages and bronchoalveolar lavage fluid of the steelworkers. Nonfibrous particles, including illite, kaolinite, talc, chlorite, amorphous silica, quartz, iron (compounds), and titanium hydroxide, were found in both groups, but the particle number per ml bronchoalveolar lavage fluid (particularly iron hydroxides and silicates) was more pronounced in blast-furnace workers. These elements and particles may act synergistically with other occupational carcinogens and cigarette smoke, the result of which may be an increased incidence of lung cancer in the ironsteel industry. PMID:7677432

  10. Use of blast-furnace slag in making durable concrete for waste management repositories

    International Nuclear Information System (INIS)

    Waste repositories for the belowground disposal of low-level radioactive waste rely greatly on the durability of concrete for their required 500-year service life. A research program is in progress based on laboratory testing of concretes containing either Type 1 cement or cements containing 65 and 75 percent of blast-furnace slag, each at 4 water-cement ratios. It has been established that the degradation of the concrete will depend on the rate of ingress of corrosive agents - chlorides, sulphate ions and CO2. The ionic profiles and the kinetics of diffusion of these ions in the concretes have been measured by Secondary Electron Microscope (SEM) and Energy Dispersive X-ray Analysis (EDXA) techniques, and the results plotted according to a mathematical model. Predictions for service life of the concrete have been made from this model. These predictions have been correlated with properties of the concrete obtained from micro-structural, thermochemical and permeability measurements. The improvements in concrete durability due to blast-furnace slag additions are illustrated and discussed

  11. Multi-parameter measurements in a blast furnace using interactions of neutrons and ?-rays

    International Nuclear Information System (INIS)

    This paper describes the possibility of multi-parameter measurements to meet the requirements for more precise and stable control of a blast furnace. A basic concept of such measurements is to make use of multi-radiations of neutrons and ?-rays, and to obtain multi-types of information on conditions of materials (iron ore and coke) inside the blast furnace. A prototype gauge was assembled and examined which consisted of a radiation source of 252Cf, a neutron moderator, a lead shield, a bismuth germanate detector, a stainless casing and a control unit. Laboratory experiments showed that the gauge could measure the quantities to be essential to estimate material conditions. In practice, it clearly distinguished between iron ore and coke layers, and at the same time measured bulk density of iron contained in iron ore by counting thermal neutron capture ?-rays from iron. It also gave the information on material bulk density by detecting Compton scattered ?-rays from material, i.e. iron ore and coke. Finally, reducibility of iron ore was calculated by using both bulk densities. Relative accuracy of measurements was reasonable in practical use. The possibility of realization of the gauge has been proved and the on-line trial will be expected in the near future. (author)

  12. Effect of recycling blast furnace flue dust as pellets on the sintering performance

    Directory of Open Access Journals (Sweden)

    El-Hussiny N.A.

    2010-01-01

    Full Text Available The Egyptian Iron and Steel Company generates a great amount of blast furnace flue dust. The recovery of metals and carbon from this flue dust becomes a very important demand due to the increase of the price of coke breeze and the decrease of the primary source of metals. At the same time, it make the environment more safe by decreasing pollution. Introducing these dust fines in the sintering process proves to be very harmful for different operating parameters. Thus, this study aims at investigating the production of pellets resulting from these fines, using molasses as organic binder and its application in sintering of iron ore. The sintering experiments were performed using flue dust as pellets as a substitute of coke breeze. The results revealed that, sintering properties such as inter strength increases with using the flue dust pellets, while productivity of both the sinter machine and sinter machine at blast furnace yard decreases. Also the vertical velocity of the sinter machine and the weight loss during the reduction of produced the sinter by hydrogen decrease.

  13. CFD study of ejector flow behavior in a blast furnace gas galvanizing plant

    Science.gov (United States)

    Besagni, Giorgio; Mereu, Riccardo; Inzoli, Fabio

    2015-02-01

    In recent years, there has been a growing interest toward Blast Furnace Gas (BFG) as a low-grade energy source for industrial furnaces. This paper considers the revamping of a galvanic plant furnace converted to BFG from natural gas. In the design of the new system, the ejector on the exhaust line is a critical component. This paper studies the flow behavior of the ejector using a Computational Fluid Dynamics (CFD) analysis. The CFD model is based on a 3D representation of the ejector, using air and exhaust gases as working fluids. This paper is divided in three parts. In the first part, the galvanic plant used as case study is presented and discussed, in the second part the CFD approach is outlined, and in the third part the CFD approach is validated using experimental data and the numerical results are presented and discussed. Different Reynolds-Averaged Navier-Stokes (RANS) turbulence models ( k-? SST and k-? Realizable) are evaluated in terms of convergence capability and accuracy in predicting the pressure drop along the ejector. Suggestions for future optimization of the system are also provided.

  14. Three-Dimensional Modeling of Flow and Thermochemical Behavior in a Blast Furnace

    Science.gov (United States)

    Shen, Yansong; Guo, Baoyu; Chew, Sheng; Austin, Peter; Yu, Aibing

    2015-02-01

    An ironmaking blast furnace (BF) is a complex high-temperature moving bed reactor involving counter-, co- and cross-current flows of gas, liquid and solid, coupled with heat and mass exchange and chemical reactions. Two-dimensional (2D) models were widely used for understanding its internal state in the past. In this paper, a three-dimensional (3D) CFX-based mathematical model is developed for describing the internal state of a BF in terms of multiphase flow and the related thermochemical behavior, as well as process indicators. This model considers the intense interactions between gas, solid and liquid phases, and also their competition for the space. The model is applied to a BF covering from the burden surface at the top to the liquid surface in the hearth, where the raceway cavity is considered explicitly. The results show that the key in-furnace phenomena such as flow/temperature patterns and component distributions of solid, gas and liquid phases can be described and characterized in different regions inside the BF, including the gas and liquids flow circumferentially over the 3D raceway surface. The in-furnace distributions of key performance indicators such as reduction degree and gas utilization can also be predicted. This model offers a cost-effective tool to understand and control the complex BF flow and performance.

  15. AN INVESTIGATION OF FOREIGN BY-PRODUCT COKE PLANT AND BLAST FURNACE WASTEWATER CONTROL TECHNOLOGY AND REGULATION

    Science.gov (United States)

    The report gives results of a study to determine if more effective wastewater control technologies for by-product coke plant and blast furnace gas-cleaning wastewaters are used in foreign plants than in the U.S. Discussions were held with plant and corporate personnel at 26 plant...

  16. The effects of ZnO2 nanoparticles on properties of concrete using ground granulated blast furnace Slag as binder

    Scientific Electronic Library Online (English)

    Ali, Nazari; Shadi, Riahi.

    2011-09-01

    Full Text Available In the present study, flexural strength together with pore structure, thermal behavior and microstructure of concrete containing ground granulated blast furnace slag with different amount of ZnO2 nanoparticles has been investigated. Portland cement was replaced by different amounts of ground granula [...] ted blast furnace slag and the properties of concrete specimens were investigated. Although it negatively impact the properties of concrete, ground granulated blast furnace slag was found to improve the physical and mechanical properties of concrete up to 45 wt. (%). ZnO2 nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of 45 wt. (%) of ground granulated blast furnace slag and physical and mechanical properties of the specimens was measured. ZnO2 nanoparticle as a partial replacement of cement up to 3 wt. (%) could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)2 amount at the early age of hydration and hence increase flexural strength of concrete. The increased the ZnO2 nanoparticles' content more than 3 wt. (%), causes the reduced the flexural strength because of the decreased crystalline Ca(OH)2 content required for C-S-H gel formation together with unsuitable dispersion of nanoparticles in the concrete matrix. ZnO2 nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and few-harm pores.

  17. Analysis of the Rheological Behaviour of Selected Semi-Solid Slag Systems in Blast Furnace Flow Conditions

    Directory of Open Access Journals (Sweden)

    Migas P.

    2015-04-01

    Full Text Available The rheological properties of liquid and semi-solid systems of slag and hot metal in a blast furnace are extremely important from the perspective of their dripping in the unit. The rheological nature and the values of the dynamic viscosity coefficient of liquid and semi-solid phases - slag and hot metal - determine the permeability of the zones in which those systems exist. The modelling of dripping processes and e.g. static and dynamic holding/retention of liquid in the bed, requires an accurate description of the rheological behaviour of slag and iron systems. Determining the liquid flow through the lump bed of the blast furnace is based on the assumption that liquids in the unit in the whole range of their occurrence are similar to a Newtonian ideal liquid. This study presents an analysis of the findings of high-temperature rheometric measurements of CaO-SiO2-Al2O3-MgO systems, liquid, semi-solid slags of the blast furnace type doped with TiO2 and solids in the form of TiN. The tests were performed within a temperature range of 1310-1490°C. Also measurement results for glycerol solutions with concentrations of 86% and 100% at the ambient temperature, simulating blast furnace slags with various contents of solids - PC, anthracite - are presented.

  18. Forecast situation of the blast furnace cohesive zone; Situacion estimada de la zona cohesiva en el horno alto

    Energy Technology Data Exchange (ETDEWEB)

    Cores, A.; Saiz de Ayala, J.; Mochon, J.; Ruiz-Bustinza, I.; Parra, R.

    2010-07-01

    A series of sinters are manufactured in the pilot plant, using a mineral mixture, like that blast furnace. The sinters are characterised, by chemical and granulometric analysis and by determining the softening and melting temperatures. In the blast furnace temperatures are determined by using a series of probes in the furnace which make it possible to locate the position of the isotherm of higher temperature of 950 degree centigrade, which correspond to the reserve thermic zone. A model has been developed, proposing and indirect estimation of the shape of the cohesive zone through the determination of the isotherm with the highest temperature in the thermic reserve zone. The values of the softening and melting temperatures of sinters can be used to estimate the isotherms limiting the cohesive zone in the 1300-1400 degree centigrade range. (Author)

  19. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Mohiuddin, Kazi, E-mail: kazi.mohiuddin@students.mq.edu.au [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia); Strezov, Vladimir; Nelson, Peter F. [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia); Stelcer, Eduard [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Evans, Tim [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia)

    2014-07-01

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 ?m. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings. - Highlights: • Urban and steelmaking industrial air particles were collected from Australia. • Size resolved air particles were analysed by using PIXE technique. • The modality types of air particles were found to be variable. • Iron was measured as the main metal at industrial sites in each particle size range. • The industrial iron fraction in the submicron size particles was found up to 95%.

  20. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia

    International Nuclear Information System (INIS)

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 ?m. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings. - Highlights: • Urban and steelmaking industrial air particles were collected from Australia. • Size resolved air particles were analysed by using PIXE technique. • The modality types of air particles were found to be variable. • Iron was measured as the main metal at industrial sites in each particle size range. • The industrial iron fraction in the submicron size particles was found up to 95%

  1. Blast furnace residues for arsenic removal from mining-contaminated groundwater.

    Science.gov (United States)

    Carrillo-Pedroza, Fco Raúl; Soria-Aguilar, Ma de Jesús; Martínez-Luevanos, Antonia; Narvaez-García, Víctor

    2014-01-01

    In this work, blast furnace (BF) residues were well characterized and then evaluated as an adsorbent material for arsenic removal from a mining-contaminated groundwater. The adsorption process was analysed using the theories of Freundlich and Langmuir. BF residues were found to be an effective sorbent for As (V) ions. The modelling of adsorption isotherms by empirical models shows that arsenate adsorption is fitted by the Langmuir model, suggesting a monolayer adsorption of arsenic onto adsorbents. Arsenate adsorption onto BF residue is explained by the charge density surface affinity and by the formation of Fe (II) and Fe (III) corrosion products onto BF residue particles. The results indicate that BF residues represent an attractive low-cost absorbent option for the removal of arsenic in wastewater treatment. PMID:25189836

  2. Experimental Studies on Concrete Replacing Fine Aggregate with Blast Furnace Slags

    Directory of Open Access Journals (Sweden)

    J. Selwyn Babu

    2014-04-01

    Full Text Available In our world today, concrete has become ubiquitous. It is hard to imagine modern life without it. Approximately five billion tonnes of concrete are used around the world each year. The increasing popularity of concrete as a construction material is placing a huge burden on the natural sand reserves of all countries. In view of the environmental problems faced today considering the fast reduction of natural resources like sand and crushed granite aggregate, engineers have become aware to extend the practice of partially replacing fine aggregate with waste materials. In this present study blast furnace slag from two sources were replaced with fine aggregate and the properties of concrete were studied. The optimum percentages of replacement of these materials were found out. The result obtained encourages the use of these materials as a replacement material for fine aggregate.

  3. Improvement of the Blast Furnace Viscosity Prediction Model Based on Discrete Points Data

    Science.gov (United States)

    Guo, Hongwei; Zhu, Mengyi; Li, Xinyu; Guo, Jian; Du, Shen; Zhang, Jianliang

    2015-02-01

    Viscosity is considered to be a significant indicator of the metallurgical property of blast furnace slag. An improved model for viscosity prediction based on the Chou model was presented in this article. The updated model has optimized the selection strategy of distance algorithm and negative weights at the reference points. Therefore, the extensionality prediction disadvantage in the original model was ameliorated by this approach. The model prediction was compared with viscosity data of slags of compositions typical to BF operations obtained from a domestic steel plant. The results show that the approach can predict the viscosity with average error of 9.23 pct and mean standard deviation of 0.046 Pa s.

  4. Hydrothermal preparation of tobermorite from blast furnace slag for Cs+ and Sr2+ sorption.

    Science.gov (United States)

    Tsutsumi, Takuma; Nishimoto, Shunsuke; Kameshima, Yoshikazu; Miyake, Michihiro

    2014-02-15

    Al-substituted 11?-tobermorite was formed by alkaline hydrothermal treatment of blast furnace slag with sodium silicate added at 180°C for 2-48 h. Effects of the hydrothermal treatment time were characterized by XRD, SEM, and isothermal adsorption of N2. Sorption characteristics of the obtained samples were examined for Cs(+) and Sr(2+). The sample obtained by hydrothermal treatment for 48 h (HT-48 h) consisted of calcium silicate hydrate (C-S-H), and Al-substituted 11?-tobermorite. The HT-48 h showed the highest performance for Cs(+) and Sr(2+) selectivity in the presence of Na(+). The interlayer Na(+) of Al-substituted 11?-tobermorite and surface Ca(2+) played an important role in selective Cs(+) and Sr(2+). PMID:24412625

  5. Analysing blast furnace data using evolutionary neural network and multiobjective genetic algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, A.; Tewary, U.; Pettersson, F.; Das, S.; Saxen, H.; Chakraborti, N.

    2010-07-15

    Approximately one year's operational data of a TATA Steel blast furnace were subjected to a multiobjective optimisation using genetic algorithms. Data driven models were constructed for productivity, CO{sub 2} content of the top gas and Si content of the hot metal, using an evolutionary neural network that itself evolved through a multiobjective genetic algorithm as a tradeoff between the accuracy of training and the network complexity. The final networks were selected using the corrected Akaike information criterion. Bi-objective optimisation studies were subsequently carried out between the productivity and CO{sub 2} content with various constraints at the Si level in the hot metal. The results indicate that a productivity increase would entail either a compromise of the CO{sub 2} fraction in the top gas or the Si content in the hot metal. The Pareto frontiers presented in this study provide the best possible parameter settings in such a scenario.

  6. Performance testing of blast furnace slag for immobilization of technetium in grout

    International Nuclear Information System (INIS)

    This paper presents preliminary results of a grout development effort to identify grout formulas that can satisfactorily sequester 99Tc contained in an existing Portsmouth Gaseous Diffusion Plant waste. Technetium is of particular concern to the US Nuclear Regulatory Commission (NRC) because of its mobility and biological activity. The mobility of technetium results in large part from the movement of the pertechnate anion [prevalent in low-level radioactive waste (LLW)] through soil and geologic strata with little or no interaction with the surrounding matrix. Ground blast furnace slag has been shown to improve the leach resistance of cement-based waste forms, particularly in regard to technetium. This improved performance has been attributed to fewer and smaller pores in the solidified slags (versus a neat cement paste) and to the reduction of the pertechnate ion to a less soluble form. 9 refs., 2 tabs

  7. Treatment of multiple injections in the iron blast furnace by the rist diagram

    Science.gov (United States)

    Kundrat, D. M.; Rist, A.

    1992-06-01

    The treatment of injections in the iron blast furnace by a graphics method in the Rist Diagram is refined further. This method employs lines and pivots to represent process conditions during an injection. Formulae locating the abscissae of the key pivots I, J, K, and L in the diagram were established and applied in a previous study of simple injections. A procedure is now introduced for multiple injections which are treated as combinations of simple injections and which employ the pivot abscissae referring to the simple injections. In this procedure, the pivot abscissa for the multiple injection is shown to be a weighted mean, be it harmonic or arithmetic, of the pivot abscissae for the primary injections.

  8. Efficiency of a blast furnace slag cement for immobilizing simulated borate radioactive liquid waste.

    Science.gov (United States)

    Guerrero, A; Goñi, S

    2002-01-01

    The efficiency of a blast furnace slag cement (Spanish CEM III/B) for immobilizing simulated radioactive borate liquid waste [containing H3BO3, NaCl, Na2SO4 and Na(OH)] has been evaluated by means of a leaching attack in de-mineralized water at the temperature of 40 degrees C over 180 days. The leaching was carried out according to the ANSI/ANS-16.1-1986 test. Moreover, changes of the matrix microstructure were characterized through porosity and pore-size distribution analysis carried out by mercury intrusion porosimetry (MIP), X-ray diffraction (XRD) and thermal analysis (TG). The results were compared with those obtained from a calcium aluminate cement matrix, previously published. PMID:12365786

  9. Process for the manufacture of briquettes suitable for coking to blast furnace coke, and its application

    Energy Technology Data Exchange (ETDEWEB)

    Kiritani, Y.; Tsuyuguchi, M.; Ibaragi, T.; Yano, K.; Sunami, Y.; Nishioka, K.

    1980-09-04

    Suitable bricquets are manufactured from coal suitable for coking to blast furnace coke, where a mixture of more than 25% of non-coking coal and less than 75% of coking coal is used with 4 to 15% by weight of binding material to produce bricquets. The coal and the binding material with a softening point of 40 to 250/sup 0/C are mixed for 2 to 5 minutes at 40 to 350/sup 0/C in a powerful mixer, which exerts a specific mixing intensity of more than 0.02 kW/kg on the mixture. The mixing can possibly be carried out below the softening temperature of the binding material.

  10. Solidification of arsenic and heavy metal containing tailings using cement and blast furnace slag.

    Science.gov (United States)

    Kim, Jung-Wook; Jung, Myung Chae

    2011-01-01

    The objective of this study is to examine the solidification of toxic elements in tailings by the use of cement and blast furnace slag. Tailings samples were taken at an Au-Ag mine in Korea. To examine the best mixing ratio of tailings and the mixture of ordinary Portland cement (OPC) and blast furnace slag (SG) of 5:5, 6:6, 7:3, and 8:2, the 7:3 ratio of tailings and OPC+SG was adapted. In addition, the mixing ratios of water and OPC + SG were applied to 10, 20, and 30 wt%. After 7, 14, and 28 days' curing, the UCS test was undertaken. A relatively high strength of solidified material (137.2 kg cm?² in average of 3 samples) at 28 days' curing was found in 20 wt% of water content (WC). This study also examined the leachability of arsenic and heavy metals (Cd, Cu, Pb, and Zn) under the Korean Standard Leaching Test, and it showed that the reductions in leachabilities of As and heavy metals of solidified samples were ranged from 76 to 99%. Thus, all the solidified samples were within the guidelines for special and hazardous waste materials by the Waste Management Act in Korea. In addition, the result of freeze-thaw cycle test of the materials indicated that the durability of the materials was sufficient. In conclusion, solidification using a 7:3 mixing ratio of tailings and a 1:1 mixture of OPC + SG with 20% of WC is one of the best methods for the remediation of arsenic and heavy metals in tailings and other contaminated materials. PMID:21063751

  11. Visualisation of a mathematical model of blast furnace operation for distance learning purposes

    Directory of Open Access Journals (Sweden)

    Babich, A.

    2005-12-01

    Full Text Available Advanced educational technologies like Virtual Laboratories are being developed and launched in order to equip customers from higher education institutions, research and industry with efficient tools, supporting their work and operating new skills-training methods. Visual Model "Blast Furnace" based on a mathematical balance model of the blast furnace process has been developed for distance learning (DL purposes. It processes entered parameters and outputs both operating and learning results. The model simulates also sinter and pellets manufacture as well as operation of hot stove. The teacher and learners can interact with each other using software interface which allows to monitor the activity of the learners, answer their questions, and analyse the learning results. The model is an ingredient of the "Virtual Lab Ironmaking".

    Se desarrollan y presentan tecnologías avanzadas de educación, como los Laboratorios Virtuales, para suministrar a los clientes de las instituciones de educación superior, investigación e industria, en apoyo de su trabajo, nuevos y eficientes métodos de operación y técnicas especiales de adiestramiento. Se ha desarrollado el Modelo Visual de "Horno Alto" basado en un modelo matemático del balance del proceso del horno alto, para fines de educación a distancia. Procesa los parámetros de entrada y salida en operación y los resultados de la enseñanza. El modelo también simula la fabricación de sinter y pelets, además de la operación de las estufas. El profesor y alumnos pueden interactuar entre sí usando un software que permite seguir la marcha de la actividad de los alumnos, responder a sus preguntas y analizar los resultados del aprendizaje. El modelo es parte del "Laboratorio Virtual de Fabricación de Arrabio".

  12. Laboratory experiments on materials for radioactive labelling of blast furnace hearth

    International Nuclear Information System (INIS)

    Currently, the monitoring of refractory lining wear of hearth blast furnace uses for labelling of locations inside brick-work only two radionuclides 110m Ag and 60 Co. Consequently a great zone of hearth being unlabelled escapes to monitoring, leading to possible dangerous perforations. For augmentation of labelled hearth surface we have initiated research on 133 Ba, 134 Ce, 152+154 Eu, 204 Cl, and 65 Zn. It is known that it is not recommendable to use for labelling these elements in pure state because these are very reactive i.e. they are unstable, except for thallium. Moreover, at hearth and crucible temperatures they are volatile. Therefore, a major aspect that we took into consideration is the radioisotope chemical form which is used for radioactive labelling. In Ba or Eu case, oxides can be used being more stable but in Cs and Tl case, oxides are not useful; it is more suitable to employ simple or double silicates. Samples containing a mixture of pig iron, slag and silicates of the hearth furnace labelling elements have been prepared. After separation the samples were crushed and analysed by activation analysis. The obtained gamma spectra have shown the presence of Ba, Cs, and Eu separately in the slag sample into which they have been melt. (author) 2 tabs., 8 refs

  13. Using a Mathematical Model of Counter-Current Flow in a Blast Furnace to Evaluate Reducibility of Iron-Ore-Bearing Raw Materials.

    Czech Academy of Sciences Publication Activity Database

    Pust?jovská, P.; T?ma, J.; Stan?k, Vladimír; K?iš?ál, Ji?í; Jursová, s.; Bilík, J.

    2015-01-01

    Ro?. 86, ?. 4 (2015), s. 320-328. ISSN 1611-3683 Institutional support: RVO:67985858 Keywords : blast furnace * ore burden reducibility * kinetic model Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.486, year: 2014

  14. Conceptual model of the 'blast furnace' version of formation of nuclear-dangerous accumulation on the Ch NPP Unit 4

    International Nuclear Information System (INIS)

    Basic provisions of conceptual model of the 'blast furnace' version of formation of nuclear-dangerous accumulation of the fuel containing materials (FCM) hidden in a zone of pro-melting of a under-reactor slab of the Chernobyl NPP Unit 4 are formulated. Formation of the fragments of the former core (FFC) with a critical mass of uranium and lava-like FCM is considered as a result of two interconnected processes - molten core/concrete interactions and melting of FFC in a bathtub of silicate fusion that was formed of the materials 'furnace charges'

  15. Bioreducer use in blast furnace ironmaking in Finland:techno-economic assessment and CO2 emission reduction potential

    OpenAIRE

    Suopajärvi, H. (Hannu)

    2015-01-01

    Abstract Most of the steel produced in the world is based on the integrated blast furnace-converter route, which is based on the use of virgin raw materials. Large amounts of fossil-based, carbon containing reductants are used in blast furnaces, which results in carbon dioxide emissions into the atmosphere. Fossil carbon dioxide emissions from steel production can be reduced by new technologies or moving from non-renewable to renewable energy sources. Biomass-based reductants could be one...

  16. Utilization of small coke in COSIPA`s blast furnace number 2; Utilizacao de small coke no alto forno II da COSIPA

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Ivanir T. de; Nascimento, Angelo C. do; Santos, Joao B. dos; Pitta, Alvaro J. [Companhia Siderurgica Paulista (Brazil)

    1989-12-31

    This work presents the test performed with the blast furnace load when coke fines were introduced to the load with sinter up to the level of 5% of the coke-base. A comparison of the blast furnace performance regarding a standard time period is presented, and it was concluded that the operation conditions were not worsened and a reduction of coke consumption was obtained. 5 refs., 5 figs., 3 tabs.

  17. An evaluation on rice husks and pulverized coal blends using a drop tube furnace and a thermogravimetric analyzer for application to a blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei-Hsin; Wu, Jheng-Syun [Department of Greenergy, National University of Tainan, Tainan 700 (China)

    2009-10-15

    To evaluate the potential of pulverized coals partially replaced by rice husks used in blast furnaces, thermal behavior of blends of rice husks and an anthracite coal before and after passing through a drop tube furnace (DTF) was investigated by using a thermogravimetry (TG). For the blends of the raw materials in the TG, fuel reaction with increasing temperature could be partitioned into three stages. When the rice husks were contained in the fuel, a double-peak distribution in the first stage was observed, as a consequence of thermal decompositions of hemicellulose, cellulose and lignin. A linear relationship between the char yield and the biomass blending ratio (BBR) developed, reflecting that synergistic effects in the pyrolytic processes were absent. This further reveals that the coal and the rice husks can be blended and consumed in blast furnaces in accordance with the requirement of volatile matter contained in the fuel. After the fuels underwent rapid heating (i.e. the DTF), a linear relationship from the thermogravimetric analyses of the unburned chars was not found. Therefore, the synergistic effects were observed and they could be described by second order polynomials. When the BBR was less than 50%, varying the ratio had a slight effect on the thermal behavior of the unburned chars. In addition, the thermal reactions of the feeding fuels and of the formed unburned chars behaved like a fingerprint. (author)

  18. Calculation of radiation attenuation coefficients in Portland cements mixed with silica fume, blast furnace slag and natural zeolite

    International Nuclear Information System (INIS)

    This paper presents the radiation attenuation coefficients expressed as mass attenuation coefficients for Portland cement, zeolite, blast furnace slag, silica fume and their mixed types in function of the Photon energy over the energy range of 1 keV to 2 MeV. It was observed that different percentages of constituents in cement and cement mixed with different additives such as zeolite, silica fume and blast furnace slag, lead to significant variations in total mass attenuation coefficients. The elemental compositions of samples were analyzed using a wavelength dispersive XRF spectrometer. The calculated values of total mass attenuation coefficients were discussed on the basis of different percentages of constituents of cement and cement mixed with different additives

  19. Similarities between pinch analysis and classical blast furnace analysis methods. Possible improvement by synthesis. Paper no. IGEC-1-004

    International Nuclear Information System (INIS)

    Pinch analysis originated at UMIST in the 1970's. It has since then been used as a method for energy analysis and optimisation of industrial systems. The blast furnace process for reducing iron oxide to molten iron is a very important process unit in the metallurgical industry. It is a counter-current shaft process with a wide temperature range and gaseous, solid and liquid phases present in different zones. Because of this the blast furnace acts as a system of different sub-processes rather than a single process. The analysis tools developed to describe the process are in some respects similar to the tools of pinch analysis. The exchange between the two fields of knowledge has yet been negligible. In this paper the methods are described and compared. Problems, possibilities and advantages with an exchange and synthesis of knowledge are discussed. (author)

  20. Build-up Factor Calculation for Ordinary Concrete, Baryte Concrete and Blast-furnace Slugges Concrete as ? Radiation Shielding

    International Nuclear Information System (INIS)

    Calculation of build up factor ordinary concrete, baryte concrete and blast-furnace sludge concrete have been carried out. The calculations have been carried out by dose rate measurement of Cs137 source before and after passing through shielding. The investigated variables were concrete type, thickness of concrete and relative possession of concrete. Concrete type variables are ordinary concrete, baryte concrete and blast sludge furnace concrete. The thickness variables were 6, 12, 18, 24, 30 and 36 cm. The relative position variables were dose to the source and close to detector. The result showed that concrete type and position did not have significant effect to build-up factor value, while the concrete thickness (r) and the attenuation coefficient (?) were influenced to the build-up factor. The higher ?r value the higher build-up factor value. (author)

  1. Conditions of coke bed in the hearth (dissection results of the hearth in Kimitsu No. 3 blast furnace)

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Y.; Yamaguchi, K.; Tsuda, A.; Shiki, C.; Katahira, H.

    1985-01-01

    For the purpose of elucidating materials behaviour in the hearth, Kimitsu No.3 blast furnace was blown out by lowering the burden surface to the tuyere level. Materials in the hearth were cooled naturally, were sampled and the properties were examined. In this report, conditions of coke bed in the hearth are shown and the rise of dead man coke from the hearth bottom is studied. 2 references.

  2. Rice husk ash as a source of silica in alkali-activated fly ash and granulated blast furnace slag systems

    OpenAIRE

    Mejía, J.M., Mejía de Gutiérrez, R.,; Puertas, F., Barba, A.

    2014-01-01

    [EN]This study assesses the viability of using an agro-industrial by-product, rice husk ash (RHA) from a Colombian rice company’s combustion facility, as a total replacement for the commercial sodium silicate ordinarily used in alkaliactivated binders. Fly ash (FA), granulated blast furnace slag (GBFS) and binary 50FA:50GBFS blended pastes were activated with a mix of sodium hydroxide and either sodium silicate or one of two types of RHA. The pastes were characterised ...

  3. Statistical analysis of the blast furnace process output parameter using arima control chart with proposed methodology of control limits setting

    OpenAIRE

    Noskievi?ová, D.

    2009-01-01

    The paper deals with the statistical analysis of the selected parameter of the blast furnace process. It was proved that analyzed measurements have been autocorrelated. ARIMA control chart was selected for their analysis as a very useful statistical process control (SPC) method. At first the methodology for control limits setting in ARIMA control charts considering the time series outlier analysis as an integral part of the ARIMA model building was designed. Then this proposal was applied to ...

  4. Statistical analysis of the blast furnace process output parameter using arima control chart with proposed methodology of control limits setting

    OpenAIRE

    Noskievi?ová, Darja

    2009-01-01

    The paper deals with the statistical analysis of the selected parameter of the blast furnace process. It was proved that analyzed measurements have been autocorrelated. ARIMA control chart was selected for their analysis as a very useful statistical process control (SPC) method. At first the methodology for control limits setting in ARIMA control charts considering the time series outlier analysis as an integral part of the ARIMA model building was designed. Then this proposal was...

  5. A New Approach for Studying Softening and Melting Behavior of Particles in a Blast Furnace Cohesive Zone

    Science.gov (United States)

    Yang, Wenjing; Zhou, Zongyan; Pinson, David; Yu, Aibing

    2015-04-01

    The cohesive zone where ferrous burden materials soften and melt plays a critical role in determining the performance and stability of a blast furnace. The softening and melting behavior of ore particles significantly affects the layer permeability and structure, and subsequently changes the gas/liquid distribution and heat transfer in the cohesive zone. Wax balls are often used in physical experiments to study the ore softening and melting behavior because of their low melting temperature. In this work, a new approach on the basis of discrete element method is established. The relationship between Young's modulus ( E) and temperature ( T) of wax balls is first proposed based on the experimental data, and then implemented into a DEM model. The particle deformation, temperature, coordination number, and gas pressure drop under conditions relevant to blast furnace operations are then examined. The results show that the proposed approach can capture the main features of softening and melting behavior of particles. On this basis, the effects of a few variables are investigated. The approach and results should be useful to the establishment of a comprehensive picture about softening and melting behavior, and its effect on blast furnace operations.

  6. The injection of ultrahigh rates of reducing gas into a modern blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Buergler, T.; Skoeld, B.E. [Voestalpine, Linz (Austria)

    2007-07-01

    The pilot plant for gas injection consists of a screw compressor unit to supply two blast furnaces with reduction gas. Almost all of the reducing gas will react in the raceway; only a small part will combust inside the tuyere. Comparing different injection systems in the case with two lances, the gas will react faster than for the one lance system where the gas is more trapped inside a beam. During the project the melting rate of the furnace was increased by more than 30 %. Injecting reducing gas compensates increased raceway adiabatic flame temperature, RAFT by higher oxygen enrichment rates. The operation results showed that a lower RAFT and low-quality raw material result in increased consumption of reducing agents. 1 kg coke oven gas, COG substitutes 0.81 kg oil and 1.03 kg coke. Sulfur input was reduced by 40 % in comparison with heavy fuel oil operation. The top-gas calorific value is increased up to 30 %. This reduces the consumption of natural gas used to control a constant calorific value in the gas network. A high hydrogen content up to 12 % is no problem for the gas consumers. Tests with simultaneous COG/BOF gas injection have shown that a decrease in the oil rate can be compensated. The replacement of a carbon-rich resultant such as coke and oil in the BF process with a carbon-lean resultant such as COG leads to an absolute reduction in the CO{sub 2} emissions of the BF process and the power plant of approximately 184.000 t/a for both BFs or 102 kg/tHM. 3 refs., 98 figs., 16 tabs., 1 annex.

  7. Phase Development of NaOH Activated Blast Furnace Slag Geopolymers Cured at 90 deg. C

    International Nuclear Information System (INIS)

    Geopolymers were synthesized from blast furnace slag activated with different levels of NaOH and cured at 90 deg. C. The crystalline and amorphous phases of the resulting geopolymers were characterized by XRD quantitative analysis, and 29Si and 27Al MAS NMR. Amorphous species are predominant in materials at all NaOH levels. In the amorphous phase, aluminium substituted silicate species (Q2(1Al)) dominated among the species of Q0, Q1, Q2(1Al) and Q2(where Qn(mAl) denotes a silicate tetrahedron [SiO4] with n bridging oxygen atoms and m adjacent tetrahedra substituted with an aluminate tetrahedron [AlO4]). In addition, it was also found that 4-fold coordination aluminium [AlO4] species (27Al chemical shift 66.1 ppm) in low NaOH containing materials differs from the species (27Al chemical shift 74.3 ppm) in high NaOH containing materials.

  8. Phase development and pore solution chemistry in ageing blast furnace slag-Portland cement blends

    International Nuclear Information System (INIS)

    Blast furnace slag (BFS) cement blends have certain advantages for their encapsulation of low and intermediate radioactive wastes. However, their hydration reactions are more complex than for Portland cement because Portland cements fully react within several years whereas slag hydration takes considerably longer. Empirical testing of blends matured for short periods, up to several years, are not therefore adequate to characterise the chemical immobilisation potential of such systems. A modelling approach is required to predict long-term properties. This paper is concerned with defining the internal environment within slag-cement matrices. The important parameters for definition are pH, Eh, solubilities and speciation in the aqueous phase, and solid phase equilibria. Compatibility studies in the CaO-CaSo4-Al2O3-SiO2-MgO-H2O system are described and compared with the results of X-ray diffraction on pastes aged up to 2 years. In addition, pore water compositions for slag-rich cements are given, and the potential for predicting their redox level (Eh) by extending the present model is discussed

  9. Dynamic shear strength of improved soil with B-type blast-furnace cement

    International Nuclear Information System (INIS)

    It is attempted to apply the improved soil using cement materials as the hardening agent to the foundation ground of the important buildings for electric power plants. The current design procedure of the improved ground is based on the static strength such as the unconfined compressive strength of the improved soil. However, it is not clear whether the static strength is relevant to seismic designs where the effects of the cyclic loading induced by the earthquake shall be considered. Hence, the authors studied the dynamic strength of the improved soil in comparison with the static strength, by executing a series of the cyclic triaxial tests with different loading frequencies and the consolidated-undrained triaxial compression tests (CUB tests) with different axial strain rates. The tested soil specimens which have the unconfined compressive strength of about 5 MPa were made in laboratory using the mixture of a dredged marine clayey soil, a B-type blast-furnace cement (300 kg/m3) and water. Both of the CUB tests and the cyclic triaxial tests showed similar results with respect to the relationships between the strength and the strain rate. The larger the compressive strain rate was, the higher the strength became. It is concluded that the static strength could be used as a sufficiently safe value in seismic designs since the strain rate of the cyclic loading induced by the earthquake is much larger than that of the static test. (author)

  10. Blast furnace slag can effectively remediate coastal marine sediments affected by organic enrichment.

    Science.gov (United States)

    Asaoka, Satoshi; Yamamoto, Tamiji

    2010-04-01

    There is an urgent need to control nutrient release fluxes from organically-enriched sediments into overlying waters to alleviate the effects of eutrophication. This study aims to characterize blast furnace slag (BFS) and evaluate its remediation performance on organically-enriched sediments in terms of suppressing nutrient fluxes and reducing acid volatile sulfide. BFS was mainly composed of inorganic substances such as CaO, SiO(2), Al(2)O(3) and MgO in amorphous crystal phase. Container experiments showed that the phosphate concentration in the overlying water, its releasing flux from sediment and AVS of the sediment decreased by 17-23%, 39% and 16% compared to the control without BFS, respectively. The loss on ignition was significantly decreased by 3.6-11% compared to the control. Thus, the application of BFS to organically-enriched sediment has a suppressive role on organic matter, AVS concentration and phosphate releasing flux from sediments and therefore, is a good candidate as an effective environmental remediation agent. PMID:20003992

  11. Thermodynamic Analysis of Blast Furnace Slag Waste Heat-Recovery System Integrated with Coal Gasification

    Science.gov (United States)

    Duan, W. J.; Li, P.; Lei, W.; Chen, W.; Yu, Q. B.; Wang, K.; Qin, Q.

    2015-05-01

    The blast furnace (BF) slag waste heat was recovered by an integrated system stage by stage, which combined a physical and chemical method. The water and coal gasification reactions were used to recover the heat in the system. Based on the first and second law of thermodynamics, the thermodynamic analysis of the system was carried out by the enthalpy-exergy diagram. The results showed that the concept of the "recovery-temperature countercurrent, energy cascade utilization" was realized by this system to recover and use the high-quality BF slag waste heat. In this system, the high-temperature waste heat was recovered by coal gasification and the relatively low-temperature waste heat was used to produce steam. The system's exergy and thermal recycling efficiency were 52.6% and 75.4%, respectively. The exergy loss of the integrated system was only 620.0 MJ/tslag. Compared with the traditional physical recycling method producing steam, the exergy and thermal efficiencies of the integrated system were improved significantly. Meanwhile, approximately 182.0 m3/tslag syngas was produced by coal gasification. The BF slag waste heat will be used integrally and efficiently by the integrated system. The results provide the theoretical reference for recycling and using the BF slag waste heat.

  12. Estimation of minimum detectable concentration of chlorine in the blast furnace slag cement concrete

    International Nuclear Information System (INIS)

    The Prompt Gamma Neutron Activation Analysis technique was used to measure the concentration of chloride in the blast furnace slag (BFS) cement concrete to assess the possibility of reinforcement corrosion. The experimental setup was optimized using Monte Carlo calculations. The BFS concrete specimens containing 0.8-3.5 wt.% chloride were prepared and the concentration of chlorine was evaluated by determining the yield of 6.11, 6.62, 7.41, 7.79 and 8.58 MeV gamma-rays. The Minimum Detectable Concentration (MDC) of chlorine in the BFS cement concrete was estimated. The best value of MDC limit of chlorine in the BFS cement concrete was found to be 0.034 ± 0.011 and 0.038 ± 0.012 wt.% for 6.11 and 6.62 MeV prompt gamma-rays. Within the statistical uncertainty the lower bound of the measured MDC of chlorine in the BFS cement concrete meets the maximum permissible limit of 0.03 wt.% of chloride set by the American Concrete Institute.

  13. Investigation of the activity level and radiological impacts of naturally occurring radionuclides in blast furnace slag.

    Science.gov (United States)

    U?ur, F A; Turhan, S; Sahan, H; Sahan, M; Gören, E; Gezer, F; Ye?ingil, Z

    2013-01-01

    The activity level and possible radiological impacts of naturally occurring radionuclides on the health of workers and members of the public, as a result of utilisation of blast furnace slag (BFS) samples as a substitute for aggregate in road construction were investigated by using a gamma-ray spectrometer and potential exposure scenarios given in Radiation Protection 122. The mean activity concentrations of the (226)Ra, (232)Th and (40)K in BFS samples were found to be 152.4, 54.9 and 183.1 Bq kg(-1), respectively. These values are compared with typical values measured in BFS samples from the European Union countries, which are 270, 70 and 240 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The values of radium equivalent activity index calculated for BFS samples were within the recommended safety limits. The highest total annual effective doses evaluated as 0.9 and 0.4 mSv y(-1) for members of the public and workers, respectively, were lower than the annual limit of 1 mSv y(-1). PMID:22826355

  14. Formation mechanism of the protective layer in a blast furnace hearth

    Science.gov (United States)

    Jiao, Ke-xin; Zhang, Jian-liang; Liu, Zheng-jian; Xu, Meng; Liu, Feng

    2015-10-01

    A variety of techniques, such as chemical analysis, scanning electron microscopy-energy dispersive spectroscopy, and X-ray diffraction, were applied to characterize the adhesion protective layer formed below the blast furnace taphole level when a certain amount of titanium- bearing burden was used. Samples of the protective layer were extracted to identify the chemical composition, phase assemblage, and distribution. Furthermore, the formation mechanism of the protective layer was determined after clarifying the source of each component. Finally, a technical strategy was proposed for achieving a stable protective layer in the hearth. The results show that the protective layer mainly exists in a bilayer form in the sidewall, namely, a titanium-bearing layer and a graphite layer. Both the layers contain the slag phase whose major crystalline phase is magnesium melilite (Ca2MgSi2O7) and the main source of the slag phase is coke ash. It is clearly determined that solid particles such as graphite, Ti(C,N) and MgAl2O4 play an important role in the formation of the protective layer, and the key factor for promoting the formation of a stable protective layer is reasonable control of the evolution behavior of coke.

  15. on the Structure and Viscous Behavior of Ti-Bearing Blast Furnace Slags

    Science.gov (United States)

    Sun, Yongqi; Liao, Junlin; Zheng, Kai; Wang, Xidong; Zhang, Zuotai

    2014-10-01

    This study provided a fundamental analysis of the viscous behavior and structure of Ti-bearing blast furnace slags modified by different B2O3 additions with a basicity (CaO/SiO2) range of 0.5-0.9. The viscosity of slag melts was measured by rotating cylinder method, and the results showed that both slag viscosity and apparent activation energy for viscous flow remarkably decreased with B2O3 addition. To connect the viscosity variation of slags to the melt structure, Fourier transformation infrared spectroscopy analysis was performed. The results indicated that B2O3 acted as a typical network forming oxide, which was introduced into the network and existed dominantly as a two-dimensional structure, BO3 triangular. With the increase of B2O3 content, the stretching vibration of BO3 triangular gradually became more pronounced, which resulted in a simpler and less complex structure and caused the decrease of slag viscosity.

  16. Modeling of a self-healing process in blast furnace slag cement exposed to accelerated carbonation

    International Nuclear Information System (INIS)

    In the current research, a mathematical model for the post-damage improvement of the carbonated blast furnace slag cement (BFSC) exposed to accelerated carbonation is constructed. The study is embedded within the framework of investigating the effect of using lightweight expanded clay aggregate, which is incorporated into the impregnation of the sodium mono-fluorophosphate (Na-MFP) solution. The model of the self-healing process is built under the assumption that the position of the carbonation front changes in time where the rate of diffusion of Na-MFP into the carbonated cement matrix and the reaction rates of the free phosphate and fluorophosphate with the components of the cement are comparable to the speed of the carbonation front under accelerated carbonation conditions. The model is based on an initial-boundary value problem for a system of partial differential equations which is solved using a Galerkin finite element method. The results obtained are discussed and generalized to a three-dimensional case.

  17. Preparation of nanometer-sized black iron oxide pigment by recycling of blast furnace flue dust.

    Science.gov (United States)

    Shen, Lazhen; Qiao, Yongsheng; Guo, Yong; Tan, Junru

    2010-05-15

    Blast furnace (BF) flue dust is one of pollutants emitted by iron and steel plants. The recycling of BF flue dust can not only reduce pollution but also bring social and environmental benefits. In this study, leaching technique was employed to the treatment of BF flue dust at first. A mixed solution of ferrous and ferric sulfate was obtained and used as raw material to prepare nanometer-sized black iron oxide pigment (Fe(3)O(4), magnetite) with NaOH as precipitant. The optimal technological conditions including total iron ion concentration, Fe(3+)/Fe(2+) mole ratio, precipitant concentration and reaction temperature were studied and discussed carefully. The spectral reflectance and oil absorption were used as major parameters to evaluate performance of pigment. Furthermore, Fe(3)O(4) particles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Under optimized conditions obtained pigment has low average spectral reflectance (<4%), good oil absorption ( approximately 23%), high black intensity, and narrow size distribution 60-70 nm. PMID:20064689

  18. Durability of traditional plasters with respect to blast furnace slag-based plaster

    International Nuclear Information System (INIS)

    Blast furnace slag is a residue of steel production. It is a latent hydraulic binder and is normally used to improve the durability of concrete and mortars. Slag could be also used as rendering mortar for masonry and old buildings. Today, cement and hydraulic lime are the most popular hydraulic binders used to make plasters. They are characterised by a low durability when exposed to the action of chemical and physical agents. The aim of this study was to provide a comparison between the physical-mechanical properties of some renders made with ordinary Portland cement, hydraulic lime, or slag. Furthermore, an investigation was carried out to analyse mortar resistance to several aggressive conditions like acid attack, freezing and thawing cycles, abrasion, sulphate aggression, cycles in ultraviolet screening device, and salt diffusion. The specimens, after chemical attack, have been characterised from the chemical-physical [specific surface according to the BET (Brunauer-Emmet-Teller) method], crystal-chemical (X-ray diffraction, XRD), and morphological (scanning electron microscopy, SEM) points of view

  19. Effect of blast furnace slag on self-healing of microcracks in cementitious materials

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Haoliang, E-mail: haoliang.huang@tudelft.nl [Microlab, Faculty of Civil Engineering and Geosciences, Delft University of Technology (Netherlands); Ye, Guang [Microlab, Faculty of Civil Engineering and Geosciences, Delft University of Technology (Netherlands); Magnel Laboratory for Concrete Research, Department of Structural Engineering, Ghent University (Belgium); Damidot, Denis [Université Lille Nord de France (France); EM Douai, LGCgE-MPE-GCE, Douai (France)

    2014-06-01

    The physico-chemical process of self-healing in blast furnace slag cement paste was investigated in this paper. With a high slag content i.e., 66% in cement paste and saturated Ca(OH)? solution as activator, it was found that the reaction products formed in cracks are composed of C-S-H, ettringite, hydrogarnet and OH–hydrotalcite. The fraction of C-S-H in the reaction products is much larger than the other minerals. Large amount of ettringite formed in cracks indicates the leaching of SO??² ions from the bulk paste and consequently the recrystallization. Self-healing proceeds fast within 50 h and then slows down. According to thermodynamic modeling, when the newly formed reaction products are carbonated, the filling fraction of crack increases first and then decreases. Low soluble minerals such as silica gel, gibbsite and calcite are formed. Compared to Portland cement paste, the potential of self-healing in slag cement paste is higher when the percentage of slag is high. Highlights: • Self-healing reaction products in slag cement paste were characterized. • Self-healing reaction products formed in time were quantified with image analysis. • Self-healing in slag cement paste was simulated with a reactive transport model. • Effect of carbonation on self-healing was investigated by thermodynamic modeling. • Effect of slag on self-healing was discussed based on experiments and simulation.

  20. on the Crystallization Behaviors of Ti-Bearing Blast Furnace Slags Using Single Hot Thermocouple Technique

    Science.gov (United States)

    Sun, Yongqi; Li, Jing; Wang, Xidong; Zhang, Zuotai

    2014-08-01

    The present paper investigates how the P2O5 addition influences the crystallization behaviors of Ti-bearing blast furnace (Ti-BF) slags with different basicity using Single Hot Thermocouple Technique. It was found that the basicity showed a significant effect on the crystallization behaviors of the Ti-BF slags, and the trend of formation of the rod-shape crystal decreased while the trend of formation of dendrite crystal increased with increasing basicity. The addition of P2O5 was found to promote the formation of rod-shape crystal. The basicity and crystallization temperature that the rod-shape crystal could be formed increased, while the incubation time of formation of the rod-shape crystal decreased with increasing P2O5 content. Scanning electron microscope equipped with energy-dispersive X-ray spectroscope and X-ray diffraction were employed to observe the morphology and determine the crystalline phase of the Ti-enriched crystals. The results indicated that the rod-shape crystal was rutile. The kinetics of the formation of rutile was studied, and the mechanism of crystallization and growth was further discussed. The results indicated that the crystallization of rutile was one-dimensional interface-controlled growth, and the nucleation rate varied with the holding time.

  1. Effect of blast furnace slag on self-healing of microcracks in cementitious materials

    International Nuclear Information System (INIS)

    The physico-chemical process of self-healing in blast furnace slag cement paste was investigated in this paper. With a high slag content i.e., 66% in cement paste and saturated Ca(OH)2 solution as activator, it was found that the reaction products formed in cracks are composed of C-S-H, ettringite, hydrogarnet and OH–hydrotalcite. The fraction of C-S-H in the reaction products is much larger than the other minerals. Large amount of ettringite formed in cracks indicates the leaching of SO42? ions from the bulk paste and consequently the recrystallization. Self-healing proceeds fast within 50 h and then slows down. According to thermodynamic modeling, when the newly formed reaction products are carbonated, the filling fraction of crack increases first and then decreases. Low soluble minerals such as silica gel, gibbsite and calcite are formed. Compared to Portland cement paste, the potential of self-healing in slag cement paste is higher when the percentage of slag is high. - Highlights: • Self-healing reaction products in slag cement paste were characterized. • Self-healing reaction products formed in time were quantified with image analysis. • Self-healing in slag cement paste was simulated with a reactive transport model. • Effect of carbonation on self-healing was investigated by thermodynamic modeling. • Effect of slag on self-healing was discussed based on experiments and simulation

  2. Investigation of the activity level and radiological impacts of naturally occurring radionuclides in blast furnace slag

    International Nuclear Information System (INIS)

    The activity level and possible radiological impacts of naturally occurring radionuclides on the health of workers and members of the public, as a result of utilisation of blast furnace slag (BFS) samples as a substitute for aggregate in road construction were investigated by using a gamma-ray spectrometer and potential exposure scenarios given in Radiation Protection 122. The mean activity concentrations of the 226Ra, 232Th and 40K in BFS samples were found to be 152.4, 54.9 and 183.1 Bq kg-1, respectively. These values are compared with typical values measured in BFS samples from the European Union countries, which are 270, 70 and 240 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The values of radium equivalent activity index calculated for BFS samples were within the recommended safety limits. The highest total annual effective doses evaluated as 0.9 and 0.4 mSv y-1 for members of the public and workers, respectively, were lower than the annual limit of 1 mSv y-1. (authors)

  3. Ultrasonic-Assisted Acid Leaching of Indium from Blast Furnace Sludge

    Science.gov (United States)

    Shen, Xingmei; Li, Liaosha; Wu, Zhaojin; Lü, Huihong; Lü, Jia

    2013-12-01

    Ultrasonic-assisted acid leaching was used to improve extraction of indium from blast furnace sludge. The effects of solid-liquid ratio, leaching temperature, and leaching time on extraction of indium were investigated and three leaching methods of high temperature acid leaching (HL), ultrasonic acid leaching (UL), and high temperature-ultrasonic acid leaching (HUL) were compared. The results show that extraction of indium increases with leaching time for all the methods. UL exhibits the lowest indium extraction. For HL, extraction of indium reaches 32.6 pct when the leaching time is 4 hours, and after 4 hours, the extraction increases slowly. Leaching temperature has a more positive effect on extraction of indium than ultrasonic. HUL can lead to a higher extraction of indium than high temperature acid leaching and UL, and extraction of indium reaches 40.4 pct when the leaching time is 2 hours. After 2 hours, no obvious increase occurs. HUL not only increases extraction of indium but also reduces the leaching time which can improve production efficiency.

  4. Ultra low and negative expansion glass–ceramic materials produced from pyrophyllite and blast furnace slag

    Indian Academy of Sciences (India)

    S Mandal; S Chakrabarti; S Ghatak; S K Das

    2005-08-01

    Ultra low and negative expansion glass–ceramic materials have been obtained from pyrophyllite and blast furnace slag. The batch composition was modified with the addition of lithium carbonate, hydrated alumina, boric acid and nucleating agent (titania). The batch was melted at 1400°C followed by casting in the form of bars and annealed at 510°C for 4 h. The annealed specimens were subjected to heat treatment at predetermined temperatures selected from DTA study of the parent glass. Thermal expansion measurement and X-ray diffraction analysis revealed that the specimen nucleated at 545°C for 4 h and crystallized at 720°C for 2 h which resulted in negative coefficient of thermal expansion [(–) 9 to (–) 2 × 10$^{-7}/{}^\\circ $C] over the temperature range (30–600°C) due to the formation of -eucryptite while other heating schedule showed the formation of spodumene and lithium aluminium silicates. The samples showed excellent flexural strength value and varied in the range 120–200 MPa depending upon the phases present.

  5. Firing blast furnace gas without support fuel in steel mill boilers

    International Nuclear Information System (INIS)

    Highlights: ? BFG or BFG+COG was burned in steel mill boilers. ? BFG was gradually added to replace COG in on-site experiments. ? As COG was decreased, the flame remained stable. ? Decreasing COG while keeping heat input constant reduced CO2 and NOx emissions. -- Abstract: In this study, the combustion characteristics of firing blast furnace gas (BFG) individually or in combination with coke oven gas (COG) were investigated theoretically and experimentally. The theoretical results showed that at the same heat release rate under the operating conditions of stoichiometry, firing BFG individually had a greater amount of fuel gas volume flow rate, a smaller amount of air volume flow rate, and a lower adiabatic flame temperature than firing BFG with support fuel without preheating. Meanwhile, the volume flow rate of flue gas for the former was greater than the latter. The experimental results obtained from a co-firing of BFG and COG fueled-boiler in a steel company showed that whether at a higher or lower boiler load, with gradually decreasing the amount of COG supply, flame instability (lift-off and blow-out) did not occur and the rate of CO emission was very low. In addition, a decrease in the amount of COG supply brought about a great benefit to the reductions of both CO2 and NOx emissions.

  6. Flow characteristics of liquid and fine particles in the lower part of blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Murai, R.; Murao, A.; Goto, K.; Sato, M.; Ariyama, T. [NKK Corp., Hiroshima (Japan). Material & Processing Research Canter

    2002-05-01

    Cold model experiments on the fine particles movement, fine particles accumulation and liquid flow in the lower part of blast furnace at the high rate injection of pulverized coal were carried out. From the experimental results of the cold model on the liquid flow, it was found that the accumulation of fine particles on the surface of deadman caused liquid flow channeling along the surface of deadman. Two-dimensional cold model on the two phase flow of gas and solid indicated that shell layer formation at the depth of raceway was conducive to accumulation of fine particles on the surface of deadman, By the one-dimensional cold model experiment of the moving bed on the two phase flow of gas and solid, it became clear that fine particles hold-up in packed bed decreased as the increase in bed descending velocity as well as decrease in fine particles feed rate or increase in superficial gas velocity. On the basis of above results, control methods of lower part permeability at higher injection rate of pulverized coal were discussed. Consequently, it was estimated that decrease in coke degradation in raceway and removal of shell layer were effective to ensure the gas flow through deadman.

  7. Solid-particle erosion of a geopolymer containing fly ash and blast-furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    K.C. Goretta; Nan Chen; F. Gutierrez-Mora; J.L. Routbort; G.C. Lukey; J.S.J. van Deventer [Argonne National Laboratory, Argonne, IL (United States). Energy Technology Division

    2004-04-01

    Solid-particle erosion studies were conducted on a geopolymer derived from fly ash and granulated blast-furnace slag. The erodent particles, 390 {mu}m angular Al{sub 2}O{sub 3}, impacted at 30, 60, or 90{sup o}at a velocity of 50, 70, or 100 m/s. Steady-state erosion rates (ER) were obtained and the material-loss mechanisms were studied by scanning electron microscopy (SEM). The geopolymer responded to normal impact as a classically brittle material. Elastic-plastic indentation events led to formation of brittle lateral cracks that resulted in loss of material; erosion rate was proportional to erodent velocity to the 2.3 power. Impact at 60{sup o} produced similar results, with the erosion rates being in general slightly lower. Impact at 30{sup o} led to anomalously high erosion rates that were approximately independent of velocity. This response was attributed to presence of microcracks in the matrix and chipping of aggregates through propagation of radial cracks.

  8. Preparation of nanometer-sized black iron oxide pigment by recycling of blast furnace flue dust

    International Nuclear Information System (INIS)

    Blast furnace (BF) flue dust is one of pollutants emitted by iron and steel plants. The recycling of BF flue dust can not only reduce pollution but also bring social and environmental benefits. In this study, leaching technique was employed to the treatment of BF flue dust at first. A mixed solution of ferrous and ferric sulfate was obtained and used as raw material to prepare nanometer-sized black iron oxide pigment (Fe3O4, magnetite) with NaOH as precipitant. The optimal technological conditions including total iron ion concentration, Fe3+/Fe2+ mole ratio, precipitant concentration and reaction temperature were studied and discussed carefully. The spectral reflectance and oil absorption were used as major parameters to evaluate performance of pigment. Furthermore, Fe3O4 particles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Under optimized conditions obtained pigment has low average spectral reflectance (<4%), good oil absorption (?23%), high black intensity, and narrow size distribution 60-70 nm.

  9. The Mechanical Properties of Foamed Concrete containing Un-processed Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Awang H.

    2014-01-01

    Full Text Available For many years, supplementary cementation materials have been utilized as cement or filler replacements to heighten the properties of concrete. The objective of this paper is to demonstrate the effects of un-processed blast furnace slag (RS on the compressive, splitting tensile and flexural strengths of foam concrete over periods of 7, 14 and 28 days. The introduction of slag to the cement begins at 30% and rises to 70% of the total content. Six mixes, which include the control mix with a similar mix ratio (1:2:0.45 and a dry density of 1300 kg/m3 is generated. Taking into consideration, from the total weight of the cementation material, 1% of super- plasticizer (PS-1 is added to the mixes with slag content. Test results revealed that the most favourable (optimum replacement level of un-processed slag in foam concrete is 30%. This represents a commercial advantage as the cement requirement is reduced from 414 Kg/m3 to 290 Kg/m3. On the 28th day, the optimum mix showed higher values than the control mix by 32% for compressive strength, 46.5% for splitting tensile strength and 61% for flexural strength.

  10. Estimation of minimum detectable concentration of chlorine in the blast furnace slag cement concrete

    Science.gov (United States)

    Naqvi, A. A.; Maslehuddin, M.; Garwan, M. A.; Nagadi, M. M.; Al-Amoudi, O. S. B.; Khateeb-ur-Rehman; Raashid, M.

    2011-01-01

    The Prompt Gamma Neutron Activation Analysis technique was used to measure the concentration of chloride in the blast furnace slag (BFS) cement concrete to assess the possibility of reinforcement corrosion. The experimental setup was optimized using Monte Carlo calculations. The BFS concrete specimens containing 0.8-3.5 wt.% chloride were prepared and the concentration of chlorine was evaluated by determining the yield of 6.11, 6.62, 7.41, 7.79 and 8.58 MeV gamma-rays. The Minimum Detectable Concentration (MDC) of chlorine in the BFS cement concrete was estimated. The best value of MDC limit of chlorine in the BFS cement concrete was found to be 0.034 ± 0.011 and 0.038 ± 0.012 wt.% for 6.11 and 6.62 MeV prompt gamma-rays. Within the statistical uncertainty the lower bound of the measured MDC of chlorine in the BFS cement concrete meets the maximum permissible limit of 0.03 wt.% of chloride set by the American Concrete Institute.

  11. A new method of embedding 60Co tracing spots in the study of erosion of blast furnace lining

    International Nuclear Information System (INIS)

    A new method-tube embedding method for monitoring the erosion feature of blast furnace lining with 60Co tracers is described. Instead of the traditional' refractory boring method', the present method is to embed specific carbon steel tubes at the predetermined spots in advance during the lining of blast furnace. After the lining work is accomplished, the holes were bored on the furnace casing and 60Co tracers are put into the tubes with special tools and then the holes are padded and sealed with carbon trimmed materials. This will eliminate the interference caused by the parallel and crossing processes of embedding 60Co and refractory lining, and avoid the constructors from being irradiated by 60Co. The construction and usage of the special tools, such as container for trasporting 60Co and spray gun are also described. As the radiatoin absorbing coefficient of the tubes sealed with carbon trimmed materials is low, the dose of 60Co used at every spot and the specific pollution activity of the site and molten iron can be decreased to a lower level than the requirement of National Specification

  12. Charcoal injection in blast furnaces (Bio-PCI: CO2 reduction potential and economic prospects

    Directory of Open Access Journals (Sweden)

    Cristobal Feliciano-Bruzual

    2014-07-01

    Full Text Available The steel industry is under pressure to reduce its CO2 emissions, which arise from the use of coal. In the long-term, the injection of pulverized particles of charcoal from biomass through blast furnace tuyeres, in this case called Bio-PCI, is an attractive method from both an environmental and metallurgical viewpoint. The potential of Bio-PCI has been assessed in terms of its CO2 abatement potential and economic viewpoint. A cost objective function has been used to measure the impact of biochar substitution in highly fuel-efficient BF among the top nine hot metal producers; estimations are based on the relevant cost determinants of ironmaking. This contribution aims to shed light on two strategic questions: Under what conditions is the implementation of Bio-PCI economically attractive? Additionally, where is such a techno-economic innovation likely to be taken up the earliest? The results indicate the potential for an 18–40% mitigation of CO2. Findings from the economic assessment show that biochar cannot compete with fossil coal on price alone; therefore, a lower cost of biochar or the introduction of carbon taxes will be necessary to increase the competitiveness of Bio-PCI. Based on the current prices of raw materials, electricity and carbon taxes, biochar should be between 130.1 and 236.4 USD/t and carbon taxes should be between 47.1 and 198.7 USD/t CO2 to facilitate the substitution of Bio-PCI in the examined countries. In regard to implementation, Brazil, followed by India, China and the USA appeared to be in a better position to deploy Bio-PCI.

  13. Characteristics and propierties of oil-well cements additioned with blast furnace slag

    Directory of Open Access Journals (Sweden)

    Sánchez, R.

    2011-06-01

    Full Text Available The present paper addresses the alkali activation of Portland cements containing blast furnace slag (20 and 30% of the cement by weight with a view to the possible use of these materials in oil well construction. The hydration studies conducted showed that in cement/slag blends, the sodium silicate activating solution partially inhibited the dissolution of the silicate phases in the Portland cement, retarding cement hydration and reducing the precipitation of reaction products. Due to such partial inhibition, the cement/slag blends had significantly lower mechanical strength than Portland cements hydrated with water. 29Si and 27Al MAS NMR and BSE/EDX studies, in turn, showed that the C-S-H gel forming in the alkali-activated cement/slag pastes contained Al in tetrahedral positions and low Ca/Si ratios.

    En el presente trabajo se ha estudiado la activación alcalina de cementos Pórtland con incorporación de escoria de horno alto (20% y 30% con respecto al peso de cemento para su posible aplicación en la construcción de pozos petrolíferos. Los estudios de hidratación realizados indican que en mezclas cemento/escoria, la disolución activadora de silicato sódico inhibe parcialmente la disolución de las fases silicato del cemento Pórtland originando un retraso de su hidratación así como la menor precipitación de productos de reacción. Dicha parcial inhibición de los procesos reactivos en las mezclas cemento/escoria originan resistencias mecánicas significativamente inferiores a las pastas de cemento Portland hidratadas con agua. Finalmente, los estudios de 29Si y 27Al RMN MAS y BSE/EDX indican que el gel C-S-H formado en pastas de mezcla cemento/escoria activadas alcalinamente presenta Al en posiciones tetraédricas y bajas relaciones Ca/Si.

  14. Structure, Growth Process, and Growth Mechanism of Perovskite in High-Titanium-Bearing Blast Furnace Slag

    Science.gov (United States)

    Liu, Lu; Hu, Meilong; Xu, Yuzhou; Bai, Chenguang; Gan, Yunhua

    2015-08-01

    The isothermal crystallization of perovskite in TiO2-CaO-SiO2-Al2O3-MgO high-titanium-bearing blast furnace slag was observed in situ at 1698 K (1425 °C) using a confocal scanning laser microscope. The dendrite structure of perovskite (CaTiO3) thus obtained showed vividly the primary dendrite trunks and secondary dendrite arms. Furthermore, the dendritic growth of perovskite in liquid slag was clearly observed on line. The results showed that the dendrite arrays in which the primary dendrite trunks observed on slag surface were parallel with each other grew toward the same direction. The secondary dendrite arms grew in the perpendicular direction with the primary trucks and stopped growing when they encounter. The perovskite dendrites showed a linear growth at two stages. The dendrites grew faster at early stage at about 5 to 7 ?m/s and grew with a lower growth rate at about 1 to 2 ?m/s in later stage. Finally, the growth mechanism of perovskite in melt was analyzed with the solidification theory. Based on the theoretical calculation of equilibrium phases in slag, the initial slag could be considered as a binary component system. One component was perovskite and the other component was the sum of all the other species that did not attend the crystallization of perovskite (included SiO2, Al2O3, and MgO, as well as CaO and TiO2 that were not involved in the solid formation). The formation of perovskite required the diffusion of CaO and TiO2 to the solid/liquid interface and the rejection of the other species from the interface. The solid/liquid equilibrium schematic diagram was made based on the calculation.

  15. [Emission characteristics of PM2.5 from blast furnace iron making].

    Science.gov (United States)

    Fan, Zhen-zhen; Zhao, Ya-li; Zhao, Hao-ning; Liang, Xing-yin; Sun, Jing-wen; Wang, Bao-gui; Wang, Ya-jun

    2014-09-01

    Electrical low pressure impactor (ELPI) was used to online analyze the PM2.5 particle size and mass concentration distribution in the trapping field and ore tank of blast furnace iron-making plant. Results showed that the grain number concentration of PM2.5 in trapping field after dust removal was in the range of 10(5)-10(6)cm-3 , and the particle size was mainly below 0. 1 ?m. While the grain number concentration of the PM2.5 in ore tank after dust removal was in the range of 10(4)-10(5) cm-3, the particle size was mainly below 1.0 ?m, and the mass concentration distribution showed a single peak. The micro-morphology of PM2.5 monomer was mainly divided into two categories, spherical particles and irregular aggregates. Chemical composition analysis indicated that the concentrations of water soluble SO(2-)(4) , K+ , Ca2+ were higher than other ions in PM2.5, with the percentage of 10. 32% -28.55% , 10. 36% -12. 15% , 3.97% -15. 4% , respectively. The major elements was Fe, Si, Al, with 16. 8% -31. 62% , 2. 24% -8.76% , 1.24% -5. 89% of total mass, respectively; organic carbon and elementary carbon were 2. 7% -4. 6% and 0. 8% -1. 3% , respectively. The emission factors of PM2.5 in trapping field and in ore tank after dust removal were ranged from 0.045 to 0.085 kg t(-1) and 0.042 to 0.071 kg t-1, respectively. PMID:25518643

  16. Durability and compressive strength of blast furnace slag-based cement grout for special geotechnical applications

    Directory of Open Access Journals (Sweden)

    Ortega, J. M.

    2014-03-01

    Full Text Available Special foundations, most prominently micropiles and soil anchors, are frequently used in construction today. In Spain, the grout for these special technical applications is generally prepared with portland cement, although the codes and standards in place stipulate only the minimum compressive strength required, with no mention of cement type. Those texts also establish a range of acceptable water:cement ratios. In the present study, durability and compressive strength in cement grout prepared with blast furnace slag cement at different w/c ratios are characterised and compared to the findings for a reference portland cement grout. The results show that slag grout exhibits greater durability than the portland cement material and complies with the compressive strength requirements laid down in the respective codes.Actualmente es muy frecuente el empleo de cimentaciones especiales, entre las que destacan los micropilotes y los anclajes. En España, las lechadas de cemento para estos trabajos geotécnicos especiales se preparan habitualmente con cemento Portland, aunque las diferentes normativas al respecto no restringen el tipo de cemento a emplear, siempre que se alcance una determinada resistencia a compresión. Respecto a la dosificación de las lechadas, la normativa permite emplear diferentes relaciones agua/cemento dentro de un determinado rango. En vista de ello, en este trabajo se han caracterizado las propiedades de durabilidad y resistencia a compresión de lechadas de cemento preparadas con un cemento con escoria de alto horno y con diferentes relaciones a/c, tomando como referencia de comportamiento lechadas de cemento Portland. El uso de un cemento con escoria conlleva una mejora en la durabilidad de las lechadas, cumpliendo los requisitos de resistencia a compresión establecidos por la normativa.

  17. Early and late hydration of supersulphated cements of blast furnace slag with fluorgypsum

    Directory of Open Access Journals (Sweden)

    Bazaldúa-Medellín, M. E.

    2015-03-01

    Full Text Available The hydration, strength development and composition of hydration products of supersulphated cements were characterized from the first 48 hours up to 360 days. Two compositions of 80% Blast furnace slag, 10–15% Fluorgypsum and 10–5% Portland cement were cured in dry and wet conditions. The main hydration products were ettringite and C-S-H since the first hours and up to 360 days as evidenced by X-ray diffraction, thermal analysis and electron microscopy. The strength was favored by higher fluorgypsum contents and lower Portland cement contents. These cements generated heats of hydration of 40–57 KJ/Kg after 28 hours, which are lower than portland cement.Se realizó la caracterización de la hidratación, desarrollo de resistencia y la composición de los productos de hidratación de los cementos supersulfatados durante las primeras 48 horas y hasta 360 días. Se estudiaron dos composiciones de 80% de Escoria de alto horno, 10–15% de Fluoryeso y 10–5% de Cemento portland, se curaron en condiciones secas y húmedas. Los principales productos de hidratación fueron etringita y C-S-H desde las primeras horas y hasta 360 días, como se evidenció por difracción de rayos X, análisis térmico y microscopía electrónica de barrido. La resistencia se favoreció con mayor contenido de fluoryeso y bajos contenidos de cemento portland. Estos cementos generaron calores de hidratación de 40–57 KJ/Kg después de 28 horas, los cuales resultan más bajos que los generados por el cemento portland.

  18. Mechanical behaviour of alkali-activated blast furnace slag-activated metakaolin blended pastes. Statistical study

    Directory of Open Access Journals (Sweden)

    Higuera, I.

    2012-06-01

    Full Text Available The study and development of alternative, more ecoefficient binders than portland cement are attracting a good deal of scientific and technological interest. Binders obtained from the chemical interaction between calcium silico-aluminous materials and highly alkaline solutions are one of several types of such possible cements. The present paper discusses the mechanical behaviour and mineralogical composition of blended pastes made from NaOH-activated vitreous blast furnace slag and metakaolin. The aim of the study was to determine how parameters such as the slag/metakaolin ratio, activating solution concentration and curing temperature affect strength development in these binders. A statistical study was conducted to establish the impact of each variable and model strength behaviour in these alkaline cements. The conclusion drawn is that activator concentration and the slag/metakaolin ratio are both determinant parameters.

    El estudio y desarrollo de cementos alternativos y más eco-eficientes que el cemento Portland es un tema de gran impacto a nivel científico y tecnológico. Entre esos posibles cementos se encuentran los cementos alcalinos que son materiales conglomerantes obtenidos por la interacción química de materiales silico-aluminosos cálcicos y disoluciones fuertemente alcalinas. En el presente trabajo se estudia el comportamiento mecánico y la composición mineralógica de mezclas de escoria vítrea de horno alto y metacaolín activadas alcalinamente con disoluciones de NaOH. El objetivo de este estudio es conocer cómo afectan parámetros tales como la relación escoria/metacaolín, la concentración de la disolución activadora y la temperatura de curado, al desarrollo resistente de las mezclas. A través del estudio estadístico realizado se ha podido establecer la influencia de cada variable y modelizar el comportamiento resistente de estos cementos alcalinos. Se concluye que la concentración del activador y la relación escoria/metacaolín son los parámetros más relevantes.

  19. Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

    Science.gov (United States)

    Drobíková, Klára; Plachá, Daniela; Motyka, Old?ich; Gabor, Roman; Kutláková, Kate?ina Mamulová; Vallová, Silvie; Seidlerová, Jana

    2016-02-01

    Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel. PMID:26684056

  20. A Novel Conversion of Ti-Bearing Blast-Furnace Slag into Water Splitting Photocatalyst with Visible-Light-Response

    Science.gov (United States)

    Lü, Huihong; Li, Ning; Wu, Xingrong; Li, Liaosha; Gao, Zhifang; Shen, Xingmei

    2013-12-01

    A novel visible-light-response photocatalyst was prepared through the heat treatment of Ti-bearing blast-furnace slag with sodium nitrate and subsequently leaching processes in which most of the SiO2, Al2O3, and MgO in Ti-slag (TS) have been separated. The photocatalytic activity of the TTS was studied by observing the evolution of H2 under the UV-Vis and visible light. Compared with the TS and commercial perovskite CaTiO3, the sample prepared exhibited an exclusive visible-light-response activity and enhanced H2 evolution.

  1. On the possibility of usage of Ba 133, Cs 134 and Eu 152 for labelling of blast furnace hearth

    International Nuclear Information System (INIS)

    The results of the augmentation of the number of the types of radionuclides suitable for labelling of the blast furnace hearth are presented. Accounting for physical, chemical, nuclear and technological properties which must be fulfilled for this purpose, it is concluded that Ba 133, Cs 134 and Eu 152 are appropriate. Using a mathematical modelling method the minimum specific detectable activity has been calculated for contaminated cylindrical slag samples measured with a NaI (Tl) scintillation detector. These results have been tested by measurements on extended plane sources of Ba 133, Cs 134 and Eu 152 of activities between 200 Bq and 1500 Bq. (Author)

  2. GRANULAR ACTIVATED CARBON ADSORPTION WITH ON-SITE INFRARED FURNACE REACTIVATION

    Science.gov (United States)

    The costs associated with the design, construction, operation, and maintenance of three 1 million gallons per day (mgd) granular activated carbon (GAC) pressure contractors and reactivation system were evaluated over a 2.4 year operational period. The reactivation system was comp...

  3. Development of analytical methods for characterizing metallurgical coke and the injectant coal chars, tars and soots formed during blast furnace operation

    OpenAIRE

    Dong, Shanning

    2008-01-01

    Blast furnace operation with coal injection at rates greater than 200 kg coal/tonne of hot metal, a rate less than the theoretical limit, has been often found problematic. The present study aims to gain a better understanding of the fate of injectant coal in the blast furnace by means of characterizing samples extracted from working BFs and pilot-scale rigs. The NMP (1-methyl-2-pyrrolidinone) solvent has been used to extract carbons relevant to BF operation, and comparison of the Size Exclusi...

  4. Implementation of top turbine of blast furnace 3 - USIMINAS Ipatinga; Implantacao da turbina de topo do alto-forno 3 - USIMINAS Unidade Ipatinga

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Murilo Alves Tito de; Rosa, Ericson Rimen Ribeiro; Oliveira, Claudiney Freitas de [Usinas Siderurgicas de Minas Gerais S/A (USIMINAS), Ipatinga, MG (Brazil)

    2010-07-01

    The use of turbine for energy recovery from top gas from blast furnace is aligned with the strategic objectives of USIMINAS Ipatinga to increase their own power generation, reduce environmental impacts and improve operational control of pressure from the top. This study aimed to present the progress in controlling the top pressure and electric power generation using turbine drawing gas kinetic energy. Will be addressed by developing methods used to control the pressure of the top from the start of operation of Blast Furnace 3 to the present day. Will also be discussed operating procedures and expected performance. (author)

  5. Fe-Si particles on the surface of blast furnace coke

    Science.gov (United States)

    Gornostayev, Stanislav S.; Heikkinen, Eetu-Pekka; Heino, Jyrki J.; Fabritius, Timo M. J.

    2015-07-01

    This study investigates the surface of unpolished samples of blast furnace (BF) coke drilled from the tuyere zone, which hosts Fe-Si particles (mostly Fe3Si) that vary in size, shape, depth of submersion (penetration) into the coke matrix, and contact features with the surface. Based on the shape of the particles and the extent of their contact with the coke matrix, they have been grouped into three major types: (I) sphere-like droplets with limited contact area, (II) semi-spheres with a larger contact area, and (III) irregular segregations with a spherical surface, which exhibit the largest contact area among the three types of particles. Considering the ratio between the height ( h) of the particles and half of their length at the surface level ( l) along the cross-section, these three types can be characterized as follows: (I) h > l, (II) h ? l, and (III) h < l. All the three types of particles can be found near each other. The shape and the extent of the contact depend on the degree of penetration of the material into the matrix, which is a function of the composition of the particles. Type (I) particles were initially saturated with Si at an earlier stage and, for that reason, they can react less with carbon in the coke matrix than type (II) and (III), thereby moving faster through the coke cone. Thermodynamic calculations have shown that the temperature interval of 1250-1300°C can be considered the starting point for Si entering into molten iron under quartz-dominated coke ash. Accordingly, the initial pick-up of Si by molten iron can be assumed to be mineral-related. In terms of BF practice, better conditions for sliding Fe-Si droplets through the coke cone are available when they come into contact with free SiO2 concentrated into small grains, and when the SiO2/?Me x O y mass ratio in the coke ash is high.

  6. The Evolution of Structural Order as a Measure of Thermal History of Coke in the Blast Furnace

    Science.gov (United States)

    Lundgren, Maria; Khanna, Rita; Ökvist, Lena Sundqvist; Sahajwalla, Veena; Björkman, Bo

    2014-04-01

    Investigations were carried out on cokes heat treated in the laboratory and on cokes extracted from the experimental blast furnace (EBF) raceway and hearth. X-ray diffraction (XRD) measurements were performed to investigate changes in structural order ( L c), chemical transformations in coke ash along with comparative thermodynamic equilibrium studies and the influence of melt. Three data processing approaches were used to compute L c values as a function of temperature and time and linear correlations were established between L c and heat treatment temperatures during laboratory investigations. These were used to estimate temperatures experienced by coke in various regions of EBF and estimated raceway temperatures were seen to follow the profile of combustion peak. The MgAl2O4 spinel was observed in coke submerged in slag during laboratory studies and in cokes found further into the raceway. Coke in contact with hot metal showed XRD peaks corresponding to presence of Fe3Si. The intensity of SiO2 peak in coke ash was seen to decrease with increasing temperature and disappeared at around 1770 K (1500 °C) due to the formation of SiC. This study has shown that the evolution of structural order and chemical transformations in coke could be used to estimate its thermal history in blast furnaces.

  7. An approach for phosphate removal with quartz sand, ceramsite, blast furnace slag and steel slag as seed crystal.

    Science.gov (United States)

    Qiu, Liping; Wang, Guangwei; Zhang, Shoubin; Yang, Zhongxi; Li, Yanbo

    2012-01-01

    The phosphate removal abilities and crystallization performance of quartz sand, ceramsite, blast furnace slag and steel slag were investigated. The residual phosphate concentrations in the reaction solutions were not changed by addition of the ceramsite, quartz sand and blast furnace slag. The steel slag could provide alkalinity and Ca(2+) to the reaction solution due to its hydration activity, and performed a better phosphate removal performance than the other three. Under the conditions of Ca/P 2.0, pH 8.5 and 10 mg P/L, the phosphate crystallization occurred during 12 h. The quartz sand and ceramsite did not improve the phosphate crystallization, but steel slag was an effective seed crystal. The phosphate concentration decreased drastically after 12 h after addition of steel slag, and near complete removal was achieved after 48 h. The XRD analysis showed that the main crystallization products were hydroxyapatite (HAP) and the crystallinity increased with the reaction time. Phosphate was successfully recovered from low phosphate concentration wastewater using steel slag as seed material. PMID:22378001

  8. Iron making technology with fuels and other materials injection in blast furnace tuyeres. Part 3. Injection of fuels mixtures and other non fuel materials

    International Nuclear Information System (INIS)

    The injection of non fuel materials (iron ores, flux s, slags, ilmenite sands), siderurgical wastes, plastics, and others, both in single form and in mixture with pulverized coal, is analyzed. As the characteristics of the injected materials, variations in the operation of blast furnace can be introduced. (Author) 47 refs

  9. TRP0033 - PCI Coal Combustion Behavior and Residual Coal Char Carryover in the Blast Furnace of 3 American Steel Companies during Pulverized Coal Injection (PCI) at High Rates

    Energy Technology Data Exchange (ETDEWEB)

    Veena Sahajwalla; Sushil Gupta

    2005-04-15

    Combustion behavior of pulverized coals (PC), gasification and thermal annealing of cokes were investigated under controlled environments. Physical and chemical properties of PCI, coke and carbon residues of blast furnace dust/sludge samples were characterized. The strong influence of carbon structure and minerals on PCI reactivity was demonstrated. A technique to characterize char carryover in off gas emissions was established.

  10. Hot metal temperature prediction by neural networks in the blast furnace; Prediccion mediante redes neuronales de la temperatura de arrabio de un horno alto. Temperatura subyacente de arrabio

    Energy Technology Data Exchange (ETDEWEB)

    Cantera, C.; Jimenez, J.; Varela, I.; Formoso, A.

    2002-07-01

    Based on a simplified model, the underlying temperature criteria is proposed as a method to study the temperature trends in a blast furnace. As an application, a neural network able to forecast hot metal temperatures from 2 to 16 h in advance (with decreasing precision) has been built. This neural network has been designed to work at real time in a production plant. (Author)

  11. Use of formed coke at blast furnace; I,II,III

    Energy Technology Data Exchange (ETDEWEB)

    Okuda, K. (and others)

    1988-03-01

    Results of a trial at Tobata no. 4 furnace with 61000 t of formed coke made in the JISF pilot plant are reported; the formed coke was used in a proportion of up to 20% of the total coke. Furnace operation was stable, with no change in carbon solution, corrected fuel rate or thermal distribution, but there was a slight decreased in permeability. The reactivity of the formed coke was higher than that of the conventional coke but was affected less by alkali accumulation in the furnace; the two cokes behaved similarly otherwise.

  12. Coke, char and organic waste behaviour in the blast furnace with high injection rate

    Directory of Open Access Journals (Sweden)

    Gudenau, H. W.

    2003-10-01

    Full Text Available Blast furnace operation with low coke rate, high amount of auxiliary hydrocarbons and use of nut coke causes a change in coke quality requirements. In particular, not burned in the raceway residues of injected substances (char and ash can influence the coke behaviour. Therefore combustion efficiency of various organic wastes with and without pulverized coal injection (PCI and coal char has been investigated under the raceway simulation conditions. Mixing of various substances improves their combustion efficiency. Study on coke gasification by carbon dioxide in the presence of char showed that with the increase of char concentration, coke strength reduction becomes smaller. The reactivity of char with CO2 is higher than that of coke. Therefore char is consumed preferentially. In presence of injected char, total pore volume in coke and its wear resistance were increased. Coke reactivity and microstructure in the presence of various kinds of ash has been studied. Many ash spheres were observed on the surface of coke matrix and its size was dependent on ash properties.

    La operación del horno alto con una tasa baja de coque, una cantidad elevada de hidrocarburos auxiliares y el empleo de coque calibrado, origina un cambio en las necesidades de calidad del coque. En particular, pueden influir en el comportamiento del coque los residuos inquemados en el raceway (cavidad enfrente a las toberas del horno de las sustancias que se inyectan (char y cenizas. El char es el residuo de carbón que se origina después que el carbón libera sus sustancias volátiles. Por tanto, se ha investigado la eficiencia de la combustión de varios residuos orgánicos con y sin inyección de carbón pulverizado (ICP y char, bajo las condiciones de simulación del raceway. La mezcla de varias sustancias mejora la eficiencia a la combustión. El estudio de la gasificación del coque por el dióxido de carbono en la presencia de char, muestra que con el aumento de la concentración del char, la resistencia del coque después de la reducción se hace más pequeña. La reactividad del char con el CO2 es más elevada que con la del coque. Por tanto, el char se consume con preferencia. En presencia del char inyectado aumentan el volumen total de poros del coque y la resistencia al desgaste. Se ha estudiado la reactividad y microestructura del coque con la presencia de distintos tipos de cenizas. Se observaron muchas esferas de ceniza sobre la superficie matriz del coque y el tamaño de las esferas depende de la naturaleza de las cenizas.

  13. The role of SiO2 nanoparticles and ground granulated blast furnace slag admixtures on physical, thermal and mechanical properties of self compacting concrete

    International Nuclear Information System (INIS)

    Research highlights: ? Nanoparticles in concrete. ? Ground granulated blast furnace slag as concrete's binder. ? Mechanical properties of concrete specimens by non-traditional admixtures. - Abstract: In this work, strength assessments and percentage of water absorption of self compacting concrete containing ground granulated blast furnace slag and SiO2 nanoparticles as binder have been investigated. Portland cement was replaced by different amounts of ground granulated blast furnace slag and the properties of concrete specimens were investigated. Although it negatively impacts the physical and mechanical properties of concrete at early ages of curing, ground granulated blast furnace slag was found to improve the physical and mechanical properties of concrete up to 45 wt% at later ages. SiO2 nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of ground granulated blast furnace slag and physical and mechanical properties of the specimens were measured. SiO2 nanoparticle as a partial replacement of cement up to 3.0 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)2 amount at the early ages and hence increase strength and improve the resistance to water permeability of concrete specimens. The increased SiO2 nanoparticles' content by more than 3.0 wt%, causes the reduced strength because of the decreased crystalline Ca(OH)2 content required for C-S-H gel formation. Several empirical relationships have been presented to predict flexural and split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of the peaks related to hydrated products in X-ray diffraction results, all indicate that SiO2 nanoparticles could improve mechanical and physical properties of the concrete specimens.

  14. [Evaluation of the migration of contaminants from building materials produced on the base of blast-furnace slags].

    Science.gov (United States)

    Pugin, K G; Vaysman, Ya I

    2014-01-01

    There is experimentally established the change of the migratory activity of pollutants from building materials produced from blast furnace slag throughout their life cycle in the form of a nonlinear wave-like nature as there are appeared newly opened surfaces of a contact with aggressive waters in the process of gradual crushing of materials as a result of destructive mechanical effects on him and corrosive waters with varying pH values. There are established regularities of the migration activity ofpollutants (on the example of heavy metals) as directly dependent on the newly opening surface of the contact of the material with water having a various pH value. There is shown an expediency of introduction of alterations in the procedure for sanitary hygienic assessment of building materials with the addition of industrial waste (Methodical Instructions 2.1.674-97), allowing to take into account the migration of contaminants from them throughout the life cycle. PMID:25842493

  15. Investigation of SrSO4 desulfurization during reductive roasting of celestite ore with blast-furnace coke

    International Nuclear Information System (INIS)

    Using the method of statistic planning of an experiment, the SrSO4 desulfurization process has been studied in the case of reductive roasting of celestine with the use blast-furnace coke. The main factors that determine the rate of the SrSO4 desulfurization are the roasting temperature and charge components dispersity. The desulfurization rate increases proportionally to the increase in the roasting temperature and dispersity of the reaction mixture components. To decrease the SrSO4 desulfurization and the concentration of sulfur-containing components in gases released at rather a high celestine reduction rate, the roasting is recommended to proceed at the temperature of 1100 to 1150 deg, in this case it is necessary to limit the content of small (less than 3.2 mm) fractions of reagents

  16. Potential usage of 133 Ba, 134 Cs, and 152 Eu in labelling of the blast furnace hearth

    International Nuclear Information System (INIS)

    The paper presents the results of the study concerning the possibility to use the radionuclides 133 Ba, 134 Cs, and 152 Eu in the labelling of the blast furnace hearth for monitoring the wear out of the refractory lining. One presents a mathematical modelling method, based on a Monte Carlo procedure which has been used to simulate the transmission of the gamma radiations in a radiometric system containing cylindrical samples of slag and a NaI(Tl) scintillation type detector. The detection probability per decay obtained with a computer program, for a sample in which one of the considered radionuclides is uniformly distributed, is used to estimate the minimum specific detectable activity; the adequate set of parameters different for each arrangement has been: radiation background, threshold energy of the detecting equipment and the measuring time interval. (author) 1 fig., 4 tabs., 5 refs

  17. Study of the devitrification and hydration of vitreous, high-magnesia blast-furnace slag by means of differential thermal analysis, thermogravimetry, X-ray diffraction and electron microscopy

    International Nuclear Information System (INIS)

    Differential Thermal Analysis (DTA) curves are presented for vitreous blast-furnace slag with a high magnesia content and an explanation for the various peaks on the curves is given. It is shown how DTA data can be used to estimate the slag content of mixtures of unhydrated Portland cement and granulated blast-furnace slag. DTA thermogravimetry (TG), X-ray diffraction (XRD) and transmission electron microscopy (TEM) data are presented for blast-furnace slag hydrated in ambient conditions, in boiling water and in steam at 215 degrees Celsius. The products of hydration are mentioned. Particular attention was paid to the role played by the magnesium in the slag during hydration

  18. Injection of natural gas in the blast furnace tuyeres three of the Usiminas, Ipatinga Plant; Injecao de gas natural nas ventaneiras do alto-forno 3 da Usiminas, Usina de Ipatinga

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Murilo Alves Tito de; Rosa, Ericson Rimen Ribeiro; Oliveira, Claudiney Freitas de; Hostt, Helton [USIMINAS, Ipatinga, MG (Brazil). Gerencia Geral de Reducao

    2011-12-21

    The reduction in production costs is a major strategic objectives of Usiminas and the use of natural gas in the Blast Furnace 3 (BF 3) contribute to achieve this goal. The use of natural gas as fuel in the BF 3 to reduce the use of metallurgical coke (main fuel) and reduces production losses during periods of maintenance in the pulverized coal injection system and improving operational control of the Blast Furnace. The work presents the deployment of the natural gas injection and the performance obtained by the BF 3 from the start of injection, with a focus on reducing consumption of metallurgical coke and stable operation of blast furnace (author)

  19. Modelamento da utilização de aglomerado autorredutor em minialto-forno com recirculação de gás de topo Modeling of self-reducing agglomerates charging in the mini blast furnace with top gas recycling

    Directory of Open Access Journals (Sweden)

    Ulysses Forastieri de Matos

    2012-03-01

    Full Text Available Os minialtos-fornos são reatores que, tradicionalmente, produzem gusa a partir de carvão vegetal, utilizando minério granular com alguma substituição de minério por carga elaborada. Nesse trabalho, propõe-se a substituição de carga metálica por aglomerado autoredutor com reaproveitamento de gás de topo reformado em minialtos-fornos com cenários onde o agente redutor seria o CV e retorno de coque de grandes altos fornos (small coque. Essa tecnologia foi avaliada, utilizando-se um código computacional do alto-forno previamente validado, tendo como base fenômenos de transporte. Diversos cenários combinando carregamento de aglomerado autorredutor e reutilização do gás de topo foram simulados. Com base nos resultados de simulação, pode-se concluir que até 45% da carga poderia ser substituída por aglomerado autorredutor combinando reutilização do gás. As melhores condições indicaram aumento de produtividade da ordem de 8% com agente redutor carvão vegetal. Resultados mostraram que reduções da ordem de 30% e 40% de agente redutor podem ser alcançadas para operações com carvão vegetal e small coque, respectivamente.Mini blast furnaces are reactors that traditionally produce pig iron from charcoal using granular ore with some agglomerate substitution. This work proposes metallic burden replacement by self-reducing agglomerates and reutilization of cleaned top gas injected into the shaft of the mini blast furnace where charcoal or small coke from a large blast furnace are used as the reducing agent. This technology was evaluated using a previously validated, blast furnace computational code based on the transport phenomena. Several scenarios combining the charging of the furnace with self-reducing agglomerates and reutilization of cleaned top gas were simulated. Based on the simulation results, it can be concluded that up to 45% of the metallic burden could be replaced by self-reducing agglomerate combined with the reutilization of the top gas. The best conditions indicated an increase in productivity of around 8% with charcoal as the reducing agent. Results showed that decreases of 30% and 40% of the reducing agent could be achieved for operations with charcoal and small coke, respectively.

  20. Effects on the Physical and Mechanical Properties of Porous Concrete for Plant Growth of Blast Furnace Slag, Natural Jute Fiber, and Styrene Butadiene Latex Using a Dry Mixing Manufacturing Process

    OpenAIRE

    Hwang-Hee Kim; Chun-Soo Kim; Ji-Hong Jeon; Chan-Gi Park

    2016-01-01

    To evaluate the effects of industrial by-products materials on the performance of porous concrete for plant growth, this study investigated the physical, strength, and freeze/thaw resistances of porous concrete for plant growth, prepared by replacing cement with blast furnace slag powder at 60% by weight, and replacing natural stone aggregates with coarse blast furnace slag aggregates at rates of 0%, 20%, 40%, 60% and 100% by weight. In addition, the effects of adding natural jute fiber and s...

  1. Nuclear methods applied in Romania in determining wear of blast furnace refractory lining

    International Nuclear Information System (INIS)

    At different points and in different depths of the refractory lining, radionuclides 60Co, 110mAg, 204Tl are placed. With the wear of the lining the radioisotopes get into contact with the pig iron in which they dissolve. The loss of isotopes which indicates the wear of the lining is detected in two ways in dependence on their location. Isotopes from the furnace bottom are detected in pig iron and in the slag, isotopes from the walls of the hump of the shaft are detected by probes placed on the furnace casing. Also applicable are methods based on the photoneutron effect. Be or BeO targets in form of a plate are placed at pre-set points in the lining. The condition of the beryllium plates is monitored using gamma radiation and neutron detectors. When wear affects the plate, the plate will disintegrate and this will show by loss of the detector signal. (J.B.). 1 fig

  2. A Novel Conversion Process for Waste Slag: The Preparation of Aluminosilicate Glass with Evaluation of the Dielectric Properties from Blast Furnace Slag

    Science.gov (United States)

    Li, Sheng; Huang, Sanxi; Liu, Hongting; Wu, Fengnian; Chang, Ziyuan; Yue, Yunlong

    2015-11-01

    In this paper, aluminosilicate glass was prepared from blast furnace slag and quartz sand. Fourier transform infrared, differential scanning calorimetry and density measurements were carried out to investigate the effects of SiO2 on the aluminosilicate glass network rigidity. The results indicate that glass structure would be enhanced if more SiO2 was introduced into the glass system. Meanwhile, both the glass transition temperature ( T g) and the glass crystallization temperature ( T c) increase slightly; the increase in density of the glass being further evidence of the enhancement in glass network rigidity. Dielectric measurements show that the dielectric constant and dielectric loss decrease with more SiO2. The properties of the prepared aluminosilicate glasses are comparable to those of E glass, indicating that blast furnace slags are suitable for producing aluminosilicate glass with low dielectric constant and dielectric loss.

  3. A Novel Conversion Process for Waste Slag: The Preparation of Aluminosilicate Glass with Evaluation of the Dielectric Properties from Blast Furnace Slag

    Science.gov (United States)

    Li, Sheng; Huang, Sanxi; Liu, Hongting; Wu, Fengnian; Chang, Ziyuan; Yue, Yunlong

    2015-09-01

    In this paper, aluminosilicate glass was prepared from blast furnace slag and quartz sand. Fourier transform infrared, differential scanning calorimetry and density measurements were carried out to investigate the effects of SiO2 on the aluminosilicate glass network rigidity. The results indicate that glass structure would be enhanced if more SiO2 was introduced into the glass system. Meanwhile, both the glass transition temperature (T g) and the glass crystallization temperature (T c) increase slightly; the increase in density of the glass being further evidence of the enhancement in glass network rigidity. Dielectric measurements show that the dielectric constant and dielectric loss decrease with more SiO2. The properties of the prepared aluminosilicate glasses are comparable to those of E glass, indicating that blast furnace slags are suitable for producing aluminosilicate glass with low dielectric constant and dielectric loss.

  4. Simultaneous removal of Ni(II), As(III), and Sb(III) from spiked mine effluent with metakaolin and blast-furnace-slag geopolymers.

    Science.gov (United States)

    Luukkonen, Tero; Runtti, Hanna; Niskanen, Mikko; Tolonen, Emma-Tuulia; Sarkkinen, Minna; Kemppainen, Kimmo; Rämö, Jaakko; Lassi, Ulla

    2016-01-15

    The mining industry is a major contributor of various toxic metals and metalloids to the aquatic environment. Efficient and economical water treatment methods are therefore of paramount importance. The application of natural or low-cost sorbents has attracted a great deal of interest due to the simplicity of its process and its potential effectiveness. Geopolymers represent an emerging group of sorbents. In this study, blast-furnace-slag and metakaolin geopolymers and their raw materials were tested for simultaneous removal of Ni(II), As(III) and Sb(III) from spiked mine effluent. Blast-furnace-slag geopolymer proved to be the most efficient of the studied materials: the experimental maximum sorption capacities for Ni, As and, Sb were 3.74 mg/g, 0.52 mg/g, and 0.34 mg/g, respectively. Although the capacities were relatively low due to the difficult water matrix, 90-100% removal of Ni, As, and Sb was achieved when the dose of sorbent was increased appropriately. Removal kinetics fitted well with the pseudo-second-order model. Our results indicate that geopolymer technology could offer a simple and effective way to turn blast-furnace slag to an effective sorbent with a specific utilization prospect in the mining industry. PMID:26598283

  5. Thermal treatment of simulant plutonium contaminated materials from the Sellafield site by vitrification in a blast-furnace slag

    Science.gov (United States)

    Hyatt, N. C.; Schwarz, R. R.; Bingham, P. A.; Stennett, M. C.; Corkhill, C. L.; Heath, P. G.; Hand, R. J.; James, M.; Pearson, A.; Morgan, S.

    2014-01-01

    Four waste simulants, representative of Plutonium Contaminated Materials (PCMs) at the Sellafield site, were vitrified through additions of Ground Granulated Blast-furnace Slag (GGBS). Ce (as a Pu surrogate) was effectively partitioned into the slag product, enriched in an amorphous CaO-Fe2O3-Al2O3-SiO2 phase when other crystalline phases were also present. Ce L3 edge XANES data demonstrated Ce to be present as trivalent species in the slag fraction, irrespective of the waste type. Estimated volume reductions of ca. 80-95% were demonstrated, against a baseline of uncompacted 200 L PCM waste drums. The dissolution behaviour of PCM slag wasteforms was investigated at 50 °C in saturated Ca(OH)2 solution under N2 atmosphere, to simulate the hyperalkaline anoxic environment of a cementitious UK Geological Disposal Facility for Intermediate Level Waste (ILW). These experiments demonstrated the performance of the slag wasteforms to be comparable to that of other vitrified ILW materials considered potentially suitable for geological disposal.

  6. Analysis on the Oversize Blast Furnace Desulfurization and a Sulfide Capacity Prediction Model Based on Congregated Electron Phase

    Science.gov (United States)

    Zhenyang, Wang; Jianliang, Zhang; Gang, An; Zhengjian, Liu; Zhengming, Cheng; Junjie, Huang; Jingwei, Zhang

    2015-09-01

    Through analyzed and regressed the actual productive desulfurization data from the oversize blast furnace (5500 m3) in north China, the relationship between the sulfur distribution parameters and the slag composition in actual production situation was investigated. As the slag and hot metal phases have their own balance sulfur content or sulfur partial pressure in gas phase, respectively, the non-equilibrium of sulfur among gas, slag, and metal phases leads to the transmission and distribution of sulfur. Combined with sulfur transmission reactions between gas, slag and metal phases, C/CO pairs equilibrium, and Wagner model, the measured sulfide capacity can be acquired using sulfur distribution ratio, sulfur activity coefficient, and oxygen activity in hot metal. Based on the theory of congregated electron phase, a new sulfide capacity prediction model (CEPM) has been developed, which has a good liner relationship with the measured sulfide capacity. Thus, using the burden structure for BF, the ironmaking slag composition can be obtained simply and can be used to reliably predict the ironmaking slag desulfurization ability a few hours later after charging under a certain temperature by CEPM.

  7. Effect of cooling rate on the crystallization behavior of perovskite in high titanium-bearing blast furnace slag

    Science.gov (United States)

    Liu, Lu; Hu, Mei-long; Bai, Chen-guang; Lü, Xue-wei; Xu, Yu-zhou; Deng, Qing-yu

    2014-11-01

    The effect of cooling rate on the crystallization of perovskite in high Ti-bearing blast furnace (BF) slag was studied using confocal scanning laser microscopy (CSLM). Results showed that perovskite was the primary phase formed during the cooling of slag. On the slag surface, the growth of perovskite proceeded via the successive production of quasi-particles along straight lines, which further extended in certain directions. The morphology and structure of perovskite was found to vary as a function of cooling rate. At cooling rates of 10 and 30 K/min, the dendritic arms of perovskite crossed obliquely, while they were orthogonal at a cooling rate of 20 K/min and hexagonal at cooling rates of 40 and 50 K/min. These three crystal morphologies thus obtained at different cooling rates respectively corresponded to the orthorhombic, cubic and hexagonal crystal structures of perovskite. The observed change in the structure of perovskite could probably be attributed to the deficiency of O2-, when Ti2O3 was involved in the formation of perovskite.

  8. Thermal treatment of simulant plutonium contaminated materials from the Sellafield site by vitrification in a blast-furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Hyatt, N.C., E-mail: n.c.hyatt@sheffield.ac.uk [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); Schwarz, R.R.; Bingham, P.A.; Stennett, M.C.; Corkhill, C.L.; Heath, P.G.; Hand, R.J. [Department of Materials Science and Engineering, The University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom); James, M.; Pearson, A. [Sellafield Ltd., Sellafield, Seascale, Cumbria CA20 1PG (United Kingdom); Morgan, S. [Sellafield Ltd., Hinton House, Risley, Warrington WA3 6GR (United Kingdom)

    2014-01-15

    Graphical abstract: Storage of 200 L drums of PCM waste at the Sellafield site, UK. Abstract: Four waste simulants, representative of Plutonium Contaminated Materials (PCMs) at the Sellafield site, were vitrified through additions of Ground Granulated Blast-furnace Slag (GGBS). Ce (as a Pu surrogate) was effectively partitioned into the slag product, enriched in an amorphous CaO–Fe{sub 2}O{sub 3}–Al{sub 2}O{sub 3}–SiO{sub 2} phase when other crystalline phases were also present. Ce L{sub 3} edge XANES data demonstrated Ce to be present as trivalent species in the slag fraction, irrespective of the waste type. Estimated volume reductions of ca. 80–95% were demonstrated, against a baseline of uncompacted 200 L PCM waste drums. The dissolution behaviour of PCM slag wasteforms was investigated at 50 °C in saturated Ca(OH){sub 2} solution under N{sub 2} atmosphere, to simulate the hyperalkaline anoxic environment of a cementitious UK Geological Disposal Facility for Intermediate Level Waste (ILW). These experiments demonstrated the performance of the slag wasteforms to be comparable to that of other vitrified ILW materials considered potentially suitable for geological disposal.

  9. Multiscale and Fractal Analysis of Silicon Content Time Series Observed in Blast Furnace Hot Metal Using Hurst Exponent Chain

    Science.gov (United States)

    Luo, Shihua; Guo, Fan; Lai, Dejian; Yan, Fang; Tang, Feilai

    2015-09-01

    Hurst exponent is an important measure of nonlinearity of dynamical time series. In this paper, using rescaled-range (R/S) analysis, multi-fractal detrended fluctuation analysis (MF-DFA) methods, the multiscale Hurst exponent (MHE) and the multiscale generalized Hurst exponent (MGHE) of coarse-grained silicon content ([Si]) time series in blast furnace (BF) hot metal were calculated. First, we collected these [Si] time series from No. 1 BF of Nanchang Iron and Steel Co. and No. 10 BF of Xinyu Iron and Steel Co. in Jiangxi Province, China. Then, we analyzed and compared the estimated Hurst exponents and the generalized Hurst exponent of these observed time series with some simulated time series. Our results show that the observed time series from these BFs have negative correlation with the Hurst exponent less than 0.5, the generalized Hurst exponent H(q) is a nonlinear function of q, and such negative correlation and local various structure persist in their moving averages of the observed time series up to lag 5 or 10.

  10. Effect of ?-irradiation on the electrical conductivity of some soda lime silicate glass containing blast furnace slag

    International Nuclear Information System (INIS)

    The effect of electric field strength on conduction in soda lime silicate glass doped with blast furnace slag with different concentration was studied and the value of jump distance was calculated. The structure and the mixed anion effect in the conductivity have been examined by measuring the electrical conductivity of glass samples at temperature ranging between 20 and 250 deg. C. The results showed that the electrical conductivity of the examined glasses are divided into three ranges depending on the temperature range. The first is from room temperature to about 49.5 deg. C, the second is at a temperature range of 60.3-104 deg. C where the glass shows a decrease in its conductivity with the increase in temperature. This was followed by another increase in the electrical conductivity with the increase in temperature. The results also showed that the glass becomes more insulating as the slag content increased. The effect of irradiation was also studied by exposing glass samples to two different irradiation doses. It can be noticed that irradiation causes an increase in the electrical conductivity, especially at high temperature. The results were discussed and correlated according to the molecular structure of the prepared glass

  11. Thermal treatment of simulant plutonium contaminated materials from the Sellafield site by vitrification in a blast-furnace slag

    International Nuclear Information System (INIS)

    Graphical abstract: Storage of 200 L drums of PCM waste at the Sellafield site, UK. Abstract: Four waste simulants, representative of Plutonium Contaminated Materials (PCMs) at the Sellafield site, were vitrified through additions of Ground Granulated Blast-furnace Slag (GGBS). Ce (as a Pu surrogate) was effectively partitioned into the slag product, enriched in an amorphous CaO–Fe2O3–Al2O3–SiO2 phase when other crystalline phases were also present. Ce L3 edge XANES data demonstrated Ce to be present as trivalent species in the slag fraction, irrespective of the waste type. Estimated volume reductions of ca. 80–95% were demonstrated, against a baseline of uncompacted 200 L PCM waste drums. The dissolution behaviour of PCM slag wasteforms was investigated at 50 °C in saturated Ca(OH)2 solution under N2 atmosphere, to simulate the hyperalkaline anoxic environment of a cementitious UK Geological Disposal Facility for Intermediate Level Waste (ILW). These experiments demonstrated the performance of the slag wasteforms to be comparable to that of other vitrified ILW materials considered potentially suitable for geological disposal

  12. Recycling ground granulated blast furnace slag as cold bonded artificial aggregate partially used in self-compacting concrete.

    Science.gov (United States)

    Geso?lu, Mehmet; Güneyisi, Erhan; Mahmood, Swara Fuad; Öz, Hatice Öznur; Mermerda?, Kas?m

    2012-10-15

    Ground granulated blast furnace slag (GGBFS), a by-product from iron industry, was recycled as artificial coarse aggregate through cold bonding pelletization process. The artificial slag aggregates (ASA) replaced partially the natural coarse aggregates in production of self-compacting concrete (SCC). Moreover, as being one of the most widely used mineral admixtures in concrete industry, fly ash (FA) was incorporated as a part of total binder content to impart desired fluidity to SCCs. A total of six concrete mixtures having various ASA replacement levels (0%, 20%, 40%, 60%, and 100%) were designed with a water-to-binder (w/b) ratio of 0.32. Fresh properties of self-compacting concretes (SCC) were observed through slump flow time, flow diameter, V-funnel flow time, and L-box filling height ratio. Compressive strength of hardened SCCs was also determined at 28 days of curing. It was observed that increasing the replacement level of ASA resulted in decrease in the amount of superplasticizer to achieve a constant slump flow diameter. Moreover, passing ability and viscosity of SCC's enhanced with increasing the amount of ASA in the concrete. The maximum compressive strength was achieved for the SCC having 60% ASA replacement. PMID:22951223

  13. Analysis on the Oversize Blast Furnace Desulfurization and a Sulfide Capacity Prediction Model Based on Congregated Electron Phase

    Science.gov (United States)

    Zhenyang, Wang; Jianliang, Zhang; Gang, An; Zhengjian, Liu; Zhengming, Cheng; Junjie, Huang; Jingwei, Zhang

    2016-02-01

    Through analyzed and regressed the actual productive desulfurization data from the oversize blast furnace (5500 m3) in north China, the relationship between the sulfur distribution parameters and the slag composition in actual production situation was investigated. As the slag and hot metal phases have their own balance sulfur content or sulfur partial pressure in gas phase, respectively, the non-equilibrium of sulfur among gas, slag, and metal phases leads to the transmission and distribution of sulfur. Combined with sulfur transmission reactions between gas, slag and metal phases, C/CO pairs equilibrium, and Wagner model, the measured sulfide capacity can be acquired using sulfur distribution ratio, sulfur activity coefficient, and oxygen activity in hot metal. Based on the theory of congregated electron phase, a new sulfide capacity prediction model (CEPM) has been developed, which has a good liner relationship with the measured sulfide capacity. Thus, using the burden structure for BF, the ironmaking slag composition can be obtained simply and can be used to reliably predict the ironmaking slag desulfurization ability a few hours later after charging under a certain temperature by CEPM.

  14. The role of SiO{sub 2} nanoparticles and ground granulated blast furnace slag admixtures on physical, thermal and mechanical properties of self compacting concrete

    Energy Technology Data Exchange (ETDEWEB)

    Nazari, Ali, E-mail: alinazari84@aut.ac.ir [Department of Technical and Engineering Sciences, Islamic Azad University (Saveh Branch), Felestin Sq., Saveh (Iran, Islamic Republic of); Riahi, Shadi [Department of Technical and Engineering Sciences, Islamic Azad University (Saveh Branch), Felestin Sq., Saveh (Iran, Islamic Republic of)

    2011-02-25

    Research highlights: {yields} Nanoparticles in concrete. {yields} Ground granulated blast furnace slag as concrete's binder. {yields} Mechanical properties of concrete specimens by non-traditional admixtures. - Abstract: In this work, strength assessments and percentage of water absorption of self compacting concrete containing ground granulated blast furnace slag and SiO{sub 2} nanoparticles as binder have been investigated. Portland cement was replaced by different amounts of ground granulated blast furnace slag and the properties of concrete specimens were investigated. Although it negatively impacts the physical and mechanical properties of concrete at early ages of curing, ground granulated blast furnace slag was found to improve the physical and mechanical properties of concrete up to 45 wt% at later ages. SiO{sub 2} nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of ground granulated blast furnace slag and physical and mechanical properties of the specimens were measured. SiO{sub 2} nanoparticle as a partial replacement of cement up to 3.0 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH){sub 2} amount at the early ages and hence increase strength and improve the resistance to water permeability of concrete specimens. The increased SiO{sub 2} nanoparticles' content by more than 3.0 wt%, causes the reduced strength because of the decreased crystalline Ca(OH){sub 2} content required for C-S-H gel formation. Several empirical relationships have been presented to predict flexural and split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of the peaks related to hydrated products in X-ray diffraction results, all indicate that SiO{sub 2} nanoparticles could improve mechanical and physical properties of the concrete specimens.

  15. Hot metal temperature prediction and simulation by fuzzy logic in a blast furnace; Prediccion y simulacion, mediante logica difusa, de la temperatura de salida del arrabio en un horno alto

    Energy Technology Data Exchange (ETDEWEB)

    Romero, M. A.; Jimenez, J.; Mochon, J.; Formoso, A.; Bueno, F. [Centro Nacional de Investigaciones Metalurgicas CENIM. Madrid (Spain); Menendez, J. L. [ACERALIA. Gijon Asturias (Spain)

    2000-07-01

    This work describes the development and further validation of a model devoted to blast furnace hot metal temperature forecast, based on Fuzzy logic principles. The model employs as input variables, the control variables of an actual blast furnace: Blast volume, moisture, coal injection, oxygen addition, etc. and it yields as a result the hot metal temperature with a forecast horizon of forty minutes. As far as the variables used to develop the model have been obtained from data supplied by an actual blast furnaces sensors, it is necessary to properly analyse and handle such data. Especial attention was paid to data temporal correlation, fitting by interpolation the different sampling rates. In the training stage of the model the ANFIS (Adaptive Neuro-Fuzzy Inference System) and the Subtractive Clustering algorithms have been used. (Author) 9 refs.

  16. Feasibility and economic analysis of solid desiccant wheel used for dehumidification and preheating in blast furnace: A case study of steel plant, Nanjing, China

    International Nuclear Information System (INIS)

    To overcome the shortcomings of huge energy consumption from conventional dehumidification using lithium bromide adsorption refrigerating (LBARD) system, a novel desiccant wheel dehumidification and preheating (DWDP) system using two-stage desiccant wheel for blast furnace is brought forward. The DWDP system was designed for dehumidification and preheating in blast furnace of steel plant. It takes waste heat in the slag flushing water as desiccant regeneration and preheating energy. To validate the feasibility of the new DWDP system, experimental studies were conducted based on a steel plant in Nanjing, China. The experiment was designed to use DWDP system in humid outdoor climates e.g. summer seasons. The experimental results indicate that the moisture removal capacity of DWDP system can reach 8.7 g/kg which will lead to the improvement of steel production by 0.9% and the coal is saved of about 2100 tons per year. With the DWDP system, the energy consumed by cooling tower of slag flushing water can decrease 7.3%. All of these energy saved equates to 10.3 million CNY annually. A comparison of initial investment and operating cost between DWDP system and LBRAD system was then carried out. The results show that the initial investment and operating cost of DWDP system is 37% and 57% of present LBARD system, and the payback period is shortened 66%. - Highlights: • A novel two-stage desiccant wheel dehumidification system for blast furnace is proposed. • Average moisture removal of 8.7 g/kg is achieved and dehumidification efficiency is 47%. • Outlet humidity ratio is less than 10 g/kg that satisfies the requirement of blast air. • Waste heat in slag flushing water is utilized and 61.4 million kJ is saved annually. • The investment and operating cost is 37% and 57% of former dehumidification system

  17. The temperature of the boundary pig iron/refractory as variable to determine the corrosion mechanism of the blast furnace hearth

    International Nuclear Information System (INIS)

    The wear of materials in the blast furnace could be carried out under the consideration of abrasion mechanisms or with the prevalence of the components chemistries and erosive resulting as of the circulation of flowing on the refractory. Nevertheless, although in determining situations the abrasion or the components chemistries could result the control mechanism, it is necessary to consider, that all the abrasion, erosion, chemical corrosion, adhesion and thermal waste-thermal shock they cooperate to the degradation of the refractory of blast furnace. For whatever the mechanisms that intervene in the wear of the materials, it results interesting to know the temperature boundary of the refractory with the solids, liquids or present gases in the furnace. In the report, it will be developed from specific form, the importance that has the temperature in the boundary refractory-pig iron on the wear of the materials of the hearth. The different hypothesis of transport (energy, quantity of movement and material) more adequate for the obtaining of the boundary temperatures will be discussed. (Author) 11 refs

  18. Properties of mortars made by uncalcined FGD gypsum-fly ash-ground granulated blast furnace slag composite binder.

    Science.gov (United States)

    Zhong, Shiyun; Ni, Kun; Li, Jinmei

    2012-07-01

    A series of novel mortars were developed from composite binder of uncalcined FGD gypsum, fly ash (FA) and ground granulated blast furnace slag (GGBFS) for the good utilization of flue gas desulphurization (FGD) gypsum. At a fixed ratio (20%) of GGBFS to the composite binder, keeping consistency of the mortar between 9.5 and 10.0 cm, the properties of the composite mortar were studied. The results show that higher water/binder (W/B) is required to keep the consistency when increasing the percentage of FGD gypsum. No obvious influences of the W/B and content of FGD gypsum on the bleeding of paste were observed which keeps lower than 2% under all experimental conditions tried. The highest compressive and flexural strengths (ratio is 20% FGD gypsum, 20% GGBFS and 60% FA) are 22.6 and 4.3 MPa at 28 days, respectively. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results indicate that massive ettringite crystals and C-S-H gels exist in the hydration products. At 90 days the mortars with FGD gypsum is dramatically smaller drying shrinkage (563-938 micro strain) than that without FGD gypsum (about 2250 micro strain). The release of the SO(4)(2-) from the mortar was analyzed, indicating that the dissolution of sulfate increases with FGD gypsum. The concentration of SO(4)(2-) releasing from the mortar with 10% FGD gypsum is almost equal to that obtained from the mortar without FGD gypsum. The release of SO(4)(2-) from the mortar with 20% FGD gypsum is 9200 mg·m(-2), which is lower than that from the mortar with 95% cement clinker and 5% FGD gypsum. PMID:22440404

  19. Rice husk ash as a source of silica in alkali-activated fly ash and granulated blast furnace slag systems

    Directory of Open Access Journals (Sweden)

    Mejía, J. M.

    2013-09-01

    Full Text Available This study assesses the viability of using an agro-industrial by-product, rice husk ash (RHA from a Colombian rice company’s combustion facility, as a total replacement for the commercial sodium silicate ordinarily used in alkaliactivated binders. Fly ash (FA, granulated blast furnace slag (GBFS and binary 50FA:50GBFS blended pastes were activated with a mix of sodium hydroxide and either sodium silicate or one of two types of RHA. The pastes were characterised for strength, mineralogy and microstructure. The findings showed that the agro-industrial by-product can be used to yield alkali-activated materials with 7-day mechanical strengths on the order of 42 MPa. The study confirmed that both amorphous silica and part of the crystalline silica present in RHA participate in the alkaline activation process, providing the alkalinity is suitably adjusted.Este estudio evalúa la viabilidad de utilizar un subproducto agroindustrial, la ceniza de cascarilla de arroz (RHA proveniente de un equipo combustor de una empresa Arrocera en Colombia, como reemplazo total de la sílice aportada por el silicato de sodio comercial en sistemas cementicios activados alcalinamente. Se prepararon pastas de ceniza volante (FA, de escoria de alto horno (GBFS y un sistema binario 50FA:50GBFS, que fueron activadas por una mezcla de silicato de sodio e hidróxido de sodio, y por dos tipos de RHA. Las mezclas se caracterizaron mecánica, mineralógica y microestructuralmente. Los resultados demuestran que es posible obtener materiales activados alcalinamente con resistencias mecánicas del orden de 42 MPa, a 7 días de curado, utilizando el subproducto agroindustrial. Este estudio corrobora que tanto la sílice amorfa como parte de la sílice cristalina presente en RHA tienen la posibilidad de participar en el proceso de activación alcalina, siempre y cuando las condiciones de alcalinidad estén adecuadamente ajustadas.

  20. Effect of Al2O3 Addition on the Precipitated Phase Transformation in Ti-Bearing Blast Furnace Slags

    Science.gov (United States)

    Li, Zhongmin; Li, Jinfu; Sun, Yongqi; Seetharaman, Seshadri; Liu, Lili; Wang, Xidong; Zhang, Zuotai

    2016-01-01

    The present paper aims to provide a fundamental understanding on phase change of Ti-enriched crystalline phase induced by Al2O3 addition in Ti-bearing blast furnace slags with different basicities using Single Hot Thermocouple Technique and X-ray Diffraction. The results showed that an increase in the Al2O3 content led to phase change from rutile or perovskite to Mg3Al4Ti8O25 and prompted crystallization of the slags with basicity of 0.60 and 0.75, whereas only CaTiO3 was precipitated at a basicity of 0.95. Both thermodynamic and kinetic analyses were conducted to study the slag crystallization, which would throw light on phase change and enhanced crystallization. To further reveal the relationship with Al2O3 addition on slag structure and crystallization, Fourier transform infrared spectroscopy and magic angle spinning-nuclear magnetic resonance were adopted, with AlO4 tetrahedra and AlO6 octahedra observed in the slag. For slags with the basicity of 0.60 and 0.75, AlO6 octahedron, which was suggested to induce the phase change from TiO2 or CaTiO3 to Mg3Al4Ti8O25, was detected at high Al2O3 content. On the other hand, in slags with the basicity of 0.95, abundant Ca2+ may be connected to TiO6 octahedra, resulting in CaTiO3 formation.

  1. Rheology and zeta potential of cement pastes containing calcined silt and ground granulated blast-furnace slag

    Directory of Open Access Journals (Sweden)

    Safi, B.

    2011-09-01

    Full Text Available This study aimed to analyse the re-use of dam silt as a supplementary binder for self-compacting concrete (SCC. When burnt, silt becomes more reactive because the kaolin it contains is converted into metakaolin. Portland cement, calcined or burnt silt and ground granulated blast furnace slag were used in this research. Cement pastes were prepared with blends containing two or three of these materials. The replacement ratio for burnt silt in both cases was 10 % and 20 % by cement weight and the ratio for the slag was a constant 30 % by weight of the blend. Rheological and zeta potential tests were conducted to evaluate paste electrokinetics and rheological behaviour. The findings showed that burnt silt is apt for use as an addition to cement for SCC manufacture.

    En el presente trabajo se ha analizado la posibilidad de utilizar los lodos procedentes de embalses como adición en la fabricación del hormigón autocompactante (HAC. Con la calcinación, estos materiales se vuelven más reactivos debido a la transformación en metacaolín, del caolín que forma parte de su composición. Las materias primas empleadas en esta investigación son: cemento Pórtland, lodos de embalse calcinados y escorias granuladas de horno alto. Se prepararon pastas de cemento con mezclas que contenían dos o tres de estos materiales. El porcentaje de reemplazo de los lodos calcinados osciló entre el 10 y el 20 % en peso del cemento, mientras que el de la escoria fue del 30 % en peso de la mezcla. Se llevaron a cabo ensayos reológicos y de potencial zeta para evaluar el comportamiento electrocinético y reológico de las distintas pastas. De acuerdo con los resultados obtenidos, una vez calcinados, los lodos de embalse son aprovechables como adición al cemento con destino a la preparación de HAC.

  2. Effects on the Physical and Mechanical Properties of Porous Concrete for Plant Growth of Blast Furnace Slag, Natural Jute Fiber, and Styrene Butadiene Latex Using a Dry Mixing Manufacturing Process

    Directory of Open Access Journals (Sweden)

    Hwang-Hee Kim

    2016-01-01

    Full Text Available To evaluate the effects of industrial by-products materials on the performance of porous concrete for plant growth, this study investigated the physical, strength, and freeze/thaw resistances of porous concrete for plant growth, prepared by replacing cement with blast furnace slag powder at 60% by weight, and replacing natural stone aggregates with coarse blast furnace slag aggregates at rates of 0%, 20%, 40%, 60% and 100% by weight. In addition, the effects of adding natural jute fiber and styrene butadiene (SB latex to these concrete mixtures were evaluated. The void ratio, compressive strength, and freeze/thaw resistance of the samples were measured. With increasing replacement rate of blast furnace aggregates, addition of latex, and mixing of natural jute fiber the void ratio of the concrete was increased. Compressive strength decreased as the replacement rate of blast-furnace slag aggregates increased. The compressive strength decreased after 100 freeze/thaw cycles, regardless of the replacement rate of blast furnace slag aggregates or of the addition of natural jute fiber and latex. The addition of natural jute fiber and latex decreased the compressive strength after 100 freeze/thaw cycles. The test results indicate that the control mixture satisfied the target compressive strength of 10 MPa and the target void ratio of 25% at replacement rates of 0% and 20% for blast furnace aggregates, and that the mixtures containing latex satisfied the criteria up to an aggregate replacement rate of 60%. However, the mixtures containing natural jute fiber did not satisfy these criteria. The relationship between void ratio and residual compressive strength after 100 freeze/thaw cycles indicates that the control mixture and the mixtures containing jute fiber at aggregate replacement rates of 20% and 40% satisfied the target void ratio of 25% and the target residual compressive strength of over 80% after 100 freeze/thaw cycles. The mixtures containing latex and aggregate replacement rates up to 60% satisfied the target void ratio and compressive strength.

  3. Properties of mortars made by uncalcined FGD gypsum-fly ash-ground granulated blast furnace slag composite binder

    International Nuclear Information System (INIS)

    Highlights: ► The mortar with uncalcined FGD gypsum has suitable workability. ► The strength of mortar with uncalcined FGD gypsum is higher than that of mortar without uncalcined FGD gypsum. ► The dry shrinkage of mortar with uncalcined FGD gypsum is lower than that of mortar without uncalcined FGD gypsum. ► The leaching of sulfate ion of mortar is studied. - Abstract: A series of novel mortars were developed from composite binder of uncalcined FGD gypsum, fly ash (FA) and ground granulated blast furnace slag (GGBFS) for the good utilization of flue gas desulphurization (FGD) gypsum. At a fixed ratio (20%) of GGBFS to the composite binder, keeping consistency of the mortar between 9.5 and 10.0 cm, the properties of the composite mortar were studied. The results show that higher water/binder (W/B) is required to keep the consistency when increasing the percentage of FGD gypsum. No obvious influences of the W/B and content of FGD gypsum on the bleeding of paste were observed which keeps lower than 2% under all experimental conditions tried. The highest compressive and flexural strengths (ratio is 20% FGD gypsum, 20% GGBFS and 60% FA) are 22.6 and 4.3 MPa at 28 days, respectively. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results indicate that massive ettringite crystals and C–S–H gels exist in the hydration products. At 90 days the mortars with FGD gypsum is dramatically smaller drying shrinkage (563–938 micro strain) than that without FGD gypsum (about 2250 micro strain). The release of the SO42- from the mortar was analyzed, indicating that the dissolution of sulfate increases with FGD gypsum. The concentration of SO42- releasing from the mortar with 10% FGD gypsum is almost equal to that obtained from the mortar without FGD gypsum. The release of SO42- from the mortar with 20% FGD gypsum is 9200 mg·m−2, which is lower than that from the mortar with 95% cement clinker and 5% FGD gypsum.

  4. Repulsion forces of superplasticizers on ground granulated blast furnace slag in alkaline media, from AFM measurements to rheological properties

    Directory of Open Access Journals (Sweden)

    Palacios, M.

    2012-12-01

    Full Text Available The electrostatic and steric repulsion induced by different superplasticizers on ground granulated blast furnace slag in alkaline media have been studied. The superplasticizers were sulfonated naphthalene, sulfonated melamine, vinyl copolymer, and polycarboxylate- based admixtures. With these superplasticizers the slag suspensions had negative zeta potentials, ranging from -3 to -10 mV. For the first time the adsorbed layer thicknesses for superplasticizers on slag using colloidal probe atomic force microscopy has been measured. To model the interparticle force interactions an effective Hamaker constant was computed from dielectric properties measured on a dense slag sample produced by spark plasma sintering. The obtained results conclude that the dispersion mechanism for all the superplasticizers studied in the present work is mainly dominated by the steric repulsion. Results were then used in a yield stress model, YODEL, to predict the yield stress with and without the superplasticizers. Predictions of the yield stress agreed well with experimental results.

    En este trabajo se ha estudiado la repulsión electrostática y estérica inducida por diferentes aditivos superplastificantes en sistemas de escoria de horno alto en medios alcalinos. Se han estudiado aditivos superplastificantes basados en naftaleno, melamina, copolímeros vinílicos y basados en policarboxilato. Estos aditivos inducen en la escoria un potencial zeta negativo, entre -3 y -10 mV. Por primera vez, se ha determinado el grosor de la capa de aditivo adsorbido sobre la escoria mediante microscopía de fuerzas atómicas (AFM. Para modelizar las fuerzas de interacción entre partículas, se ha determinado la constante efectiva de Hamaker de la escoria a partir de las propiedades dieléctricas de una muestra de escoria obtenida mediante sinterización spark plasma sintering. Los resultados obtenidos concluyen que el mecanismo de dispersión de los superplastificantes estudiados en este trabajo está gobernado fundamentalmente por la repulsión estérica. Utilizando el modelo YODEL se ha podido predecir el esfuerzo de cizalla umbral de sistemas de escoria con y sin superplastificantes. Los resultados calculados están de acuerdo con los valores de esfuerzo de cizalla determinados experimentalmente.

  5. Blast furnace slag of a ferrosilicon firm in aswan governorate, Upper Egypt, as an adsorbent for the removal of merocyanine dye from its aqueous solution.

    Science.gov (United States)

    Taha, Gharib Mahmoud; Mosaed, Taghreed Mahmoud

    2010-04-01

    The adsorption potential of the blast furnace slag of a ferrosilicon firm in Aswan Governorate, Egypt, to decolorize aqueous solutions of 3-methyl-1-phenylpyrazol-5-one 4[2] merocyanine dye (1) was investigated at room temperature. The influence of the solution pH, the quantity of adsorbent, the initial concentration of 1, and the applied contact time were studied with the batch technique. The maximum percentage of removal of 1 was observed at pH 4. The adsorption data were better fitted by the Freundlich than by the Langmuir adsorption isotherm model, confirming the formation of monolayers of 1 on the adsorbent surface. Kinetic rate constants and the transient behavior at different initial concentrations of 1 were determined with both the Lagergren pseudo-first-order and the Ho and McKay pseudo-second-order kinetic models. The calculated kinetic parameters revealed that the adsorption of 1 on blast furnace slag followed a second-order chemisorption process. PMID:20397223

  6. Characterisation of Ba(OH)2–Na2SO4–blast furnace slag cement-like composites for the immobilisation of sulfate bearing nuclear wastes

    International Nuclear Information System (INIS)

    Soluble sulfate ions in nuclear waste can have detrimental effects on cementitious wasteforms and disposal facilities based on Portland cement. As an alternative, Ba(OH)2–Na2SO4–blast furnace slag composites are studied for immobilisation of sulfate-bearing nuclear wastes. Calcium aluminosilicate hydrate (C–A–S–H) with some barium substitution is the main binder phase, with barium also present in the low solubility salts BaSO4 and BaCO3, along with Ba-substituted calcium sulfoaluminate hydrates, and a hydrotalcite-type layered double hydroxide. This reaction product assemblage indicates that Ba(OH)2 and Na2SO4 act as alkaline activators and control the reaction of the slag in addition to forming insoluble BaSO4, and this restricts sulfate availability for further reaction as long as sufficient Ba(OH)2 is added. An increased content of Ba(OH)2 promotes a higher degree of reaction, and the formation of a highly cross-linked C–A–S–H gel. These Ba(OH)2–Na2SO4–blast furnace slag composite binders could be effective in the immobilisation of sulfate-bearing nuclear wastes

  7. Preparation of perovskite type titanium-bearing blast furnace slag photocatalyst doped with sulphate and investigation on reduction Cr(VI) using UV-vis light

    International Nuclear Information System (INIS)

    Perovskite type titanium-bearing blast furnace slag (TBBFS) and sulphate-modified titanium-bearing blast furnace slag (SO42-/TBBFS) photocatalysts were prepared by the high-energy ball milling method at different calcination temperature. The photocatalysts were characterized by XRD, FTIR, UV-vis diffuse reflectance spectra and SEM measurements. The photocatalytic activities of the different catalysts were evaluated by the photocatalytic reduction of Cr(VI) under UV-vis light irradiation. For the photocatalytic reduction of Cr(VI), the photocatalytic activities of TBBFS catalysts were found to be strongly dependent of the calcination temperature and TBBFS calcined at 700 deg. C showed a higher photocatalytic activity compared to other TBBFS catalysts. In contrast, sulphation of TBBFS improved the photocatalytic activities of SO42-/TBBFS catalysts. At low calcination temperature, the photocatalytic activities of SO42-/TBBFS catalysts were markedly higher than TBBFS prepared under high calcination temperature, suggesting that the presence of surface SO42- favored the photocatalytic reduction of Cr(VI)

  8. Energy saving in the pig iron production in the blast furnace no. 5; Ahorro de energia en la produccion de arrabio en el alto horno No. 5

    Energy Technology Data Exchange (ETDEWEB)

    Gil Diaz, Ricardo A.; J Quiroz, Francisco; Rodriguez, Rita Patricia; Banuelos Garza, Yolanda [Altos Hornos de Mexico, S. A., Coahuila (Mexico)

    1993-12-31

    Altos Hornos de Mexico (AHMSA) is an iron and steel industry integrated to Grupo Acereros del Norte in Monclova, in the Coahuila state. With an a installed capacity of 3.1 millions of tons per annum o liquid steel. In its installations, AHMSA has the highest capacity blast furnace installed in Mexico, blast furnace No. 5, that has a useful volume of 2,163 cubic meters, designed to produce 4,800 tons of pig iron per day. The basic goal to achieve in the operations involved in the production of steel through the pig iron production in the blast furnace, is the hot metal production at the lowest attainable cost within the quality requirements specified by the steel makers. The most important criterion for the recognition of the attained success is the fuel consumption per ton of pig iron produced, with coke as the main fuel fed to the blast furnace and therefore of the greatest impact on the final product cost. AHMSA contemplated within its strategic plan, the reduction in the production of its coking plants derived from the natural aging of its furnaces, consequently it is pending the shortage of coke for productions higher than 2.6 MMT of liquid iron. In response to this, and faced to the true need of diminishing the production costs in the process of making pig iron, new practices have been implemented in the use of complementary fuels to partially substitute the metallurgical coke as an energy source for the blast furnace process. The use of natural gas, fuel oil and the gradual increase of the temperature of hot blow, have strongly impacted the metallurgical coke consumption, lowering it considerably and diminishing the costs per ton of pig iron in blast furnace No. 5. Another important issue, is the utilization of coke fines resulting form the sieving of the same, directly fed to the furnace load. This practice reduced the coke consumption, and most of all, the output of our coking plants was increased on being utilized at the maximum coke production. Summarizing, the modern practices in the use of the auxiliary fuels, implemented in the AHMSA blast furnaces, have derived benefits, succeeding in diminishing the productions costs in the pig iron production process, faced to the true need of standing out in the even more competitive world of iron and steel industry of the world. [Espanol] Altos Hornos de Mexico es una industria siderurgica integrada al Grupo Acereros del Norte, localizada en la ciudad de Monclova Coahuila, contando con una capacidad anual instalada de 3.1 MMT de acero liquido. Dentro de sus instalaciones, AHMSA cuenta con el alto horno de mayor capacidad instalado en Mexico, el alto horno No. 5, el cual tiene un volumen util de 2,163 metros cubicos disenado para producir 4,800 toneladas de arrabio por dia. La meta basica a lograr en las operaciones involucradas en la elaboracion de acero via elaboracion de arrabio en el alto horno, es la produccion de metal caliente al mas bajo costo posible y dentro de los requerimientos de calidad especificado por las acerias. El mas importante criterio para la medicion del exito alcanzado es el consumo de combustible por tonelada de arrabio producida, siendo el coque el principal combustible alimentado al alto horno y por ende el que mayor impacto tiene sobre el costo final del producto. AHMSA contemplo dentro de su plan estrategico, la disminucion de produccion de sus plantas coquizadoras derivadas del envejecimiento natural de sus hornos, consecuencia de esto se hace inminente el deficit de coque para producciones mayores de 2.6 MMT de acero liquido. En respuesta a esto, y ante la verdadera necesidad de disminuir los costos de produccion en el proceso de elaboracion de arrabio, se han implementado nuevas practicas en el uso de los combustibles auxiliares que sustituyan en parte el consumo de coque metalurgico como fuente de energia en el proceso del alto horno. El uso del gas natural, combustoleo y el incremento paulatino de la temperatura de soplo caliente, han repercutido fuertemente en el consumo de coque metalurgico disminuyendolo considerablemente bajando los costos de produccion de la tonelada de arrabio en el alto horno 5. Otro punto importante, es la utilizacion de los finos de coque resultante del cribado del mismo, alimentandolos directamente a la carga del horno. Esta practica disminuyo el consumo de coque y sobre todo se incrementaron los rendimientos de nuestras plantas coquizadoras al ser utilizado al maximo el coque producido. En resumen, las practicas modernas en el uso de los combustibles auxiliares implementadas en los altos hornos de AHMSA, han dado sus frutos, logrando disminuir los costos de produccion en el proceso de fabricacion de arrabio ante la verdadera necesidad de sobresalir en el mundo mas competido de la industria siderurgica mundial.

  9. Use of pulse-type x-ray analyzers to determine the level and profile of the stock in a blast furnace

    International Nuclear Information System (INIS)

    The Leningrad Scientific-Industrial Association Burevestnik collaborated with the Chermetavtomatika Scientific-Industrial Association and the TsNIIchermet to develop a pulse-type x-ray analyzer to determine the level and profile of the stockline in a blast furnace for purposes of monitoring and optimizing the control of the smelting process. The analyzer is called ''TAIR'' and is based on the transit-time method of measurement. It includes a scanning x-ray generator, transducer, detector, data analysis and display block, and scanning control block. The generator consists of an x-ray tube, a modulator, and a high-voltage plate power source for the tube. The analyzer made it possible to adjust the instruments on the furnace during operation. Besides the stockline profile, the analyzer can be used to determine the thickness of the layer of the charge and the rate of descent of the charge. It can also produce the characteristics of the gas in the furnace above the stock

  10. The determination of Fe, Mn and Ca in sintered iron and blast-furnace slag by X-ray fluorescent analyses of energy and wave dispersion-comparison of results

    International Nuclear Information System (INIS)

    The results of sintered iron and of blast-furnace slag examination obtained by X-ray fluorescent analyses of energy and of wave dispersion are compared. They show that the methods are comparable for such elements as Ca and Fe, whereas for Mn (in sinter) the X-ray fluorescent analysis of wave dispersion is less precise. (author)

  11. PETROBRAS green petroleum coke used as partial replacement for coal injected mixtures in blast furnaces; Utilizacao do coque verde de petroleo da PETROBRAS em substituicao parcial ao carvao mineral das misturas injetadas em altos fornos

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Agenor Medrado da; Medrado, Swami Botelho; Noblat, Sebastiao Jorge Xavier [Companhia Siderurgia Nacional. CSN. Gerencia Geral de Processos Siderurgicos. RJ (Brazil)], e-mails: ams@csn.com.br, swami@csn.com.br, s.noblat@csn.com.br; Carvalho Junior, Joao Andrade de [Universidade Estadual Paulista Julio de Mesquita Filho. Faculdade de Engenharia de Guaratingueta. Departamento de Energia, SP (Brazil)], e-mail: joao@feg.unesp.br

    2010-04-15

    The PETROBRAS produced green petroleum coke (GPC) is a carbon rich fuel, virtually ash-free, with low sulfur content and is a fuel suitable to replace metallurgical coke in blast furnaces. The GPC was tested in a pulverized coal injection simulator built in the Volta Redonda research center. It presented a low burning efficiency due to low volatile material content and high substitution rate by the carbon content. The industrial-scale tests were carried out in blast furnaces with up to 50% PETROBRAS GPC in the coal blends, which has never been done before in the steel industry. The injected coal/CVP mixtures produced no negative side effects in the blast furnace grinding systems, pneumatic conveying or operating process. The mixture burning process inside the blast furnace, showed a decrease in fuel consumption, with a significant reduction in metallurgical coke consumption. The industrial-scale tests of the GPC mixtures did not reach the 70% maximum for lack of the GPC feedstock, it being necessary to continue with standard coal mixtures. (author)

  12. Influence of the activator concentration on the kinetics of the alkaline activation process of a blast furnace slag

    Directory of Open Access Journals (Sweden)

    Fernández-Jiménez, A.

    1997-06-01

    Full Text Available The influence of activator solution concentration on hydration kinetics of an alkaline activated blast furnace slag has been studied. The alkaline activator used was a mix of waterglass (Na2SiO3?nH2O and NaOH solution (of variable concentration. Final activator concentrations were 3,4 and 5 % Na2O wt. with respect to the slag total weight. Degree of reaction (? was determined from hydration heat values obtained through isothermal conduction calorimetry. From the results obtained it is deduced that a treshold value of 4 % Na2O wt. exists. For those concentrations and at test temperatures (except for 25ºC and 3 % Na2O wt., the mechanism controlling hydration reaction for a values higher than 0.5, is a diffusion process. This process is described by .Jander equation [D3=(1-(1-?1/32=(k/r2t=0,0426(t/t0,5]. The activation energy obtained for that process is of approximately 50-58 Kj/mol.

    Se ha estudiado la influencia de la concentración de la disolución activante en la cinética de hidratación de una escoria granulada de alto horno, activada alcalinamente a distintas temperaturas. El activador alcalino utilizado fue una mezcla de water glass (Na2SiO3?nH2O con una disolución de NaOH (de concentración variable. Las concentraciones finales del activador alcalino fueron: 3, 4 y 5 % en peso de Na2O respecto a la masa total de escoria. El grado de reacción (? se determinó a partir de valores de calor de hidratación obtenidos por calorimetría de conducción isotérmica. De los resultados obtenidos se deduce que existe un valor umbral de concentraciones en torno al 4 % en peso de Na2O. También para dichas concentraciones y a las temperaturas de ensayo (excepto a 25ºC con un 3 % en peso de Na2O, el mecanismo que controla la reacción de hidratación para valores de ? > 0,5 es la difusión. Este proceso viene descrito por la ecuación de Jander[D3=(1-(1-?1/32=(k/r2t=0,0426(t/t0,5]. La energía de activación obtenida para dicho proceso es del orden de 50-58 kj/mol.

  13. Operation of blast furnace gas (BFG) gas holder with ld gas (LDG); Operacao do gasometro de gas de alto forno com gas de aciaria

    Energy Technology Data Exchange (ETDEWEB)

    Sampaio, William Genelhu; Valentino, Waldir Smith [Usinas Siderurgicas de Minas Gerais S/A (USIMINAS), Ipatinga, MG (Brazil)

    2010-07-01

    The Intendente Camara plant, one of USIMINAS steel works, located in Ipatinga - MG, operates its network of process gases with two Coke-Oven Gas (COG) oil-seal gas holders, one Blast Furnace Gas (BFG) oil-seal gas holder and a LD gas (LDG) telescope type gas holder. During the repair of LDG gas holder, this gas would be completely burned in the flares for a period of five months. Due to this loss, the cost of additional fuel and interventions in the production rhythm of the Hot Strip Mill, its biggest consumer, would be high. This paper presents the philosophy and pillars that mitigated these losses, highlighting how it was possible to operate the BFG gas holder with LDG, the achieved economy and lessons learned from the process. (author)

  14. The Influence of Allocation on the Carbon Footprint of Electricity Production from Waste Gas, a Case Study for Blast Furnace Gas

    Directory of Open Access Journals (Sweden)

    Joeri Van Mierlo

    2013-03-01

    Full Text Available Producing electricity from waste gas is an after treatment for waste gas while recovering the energy content. This paper addresses the methodology to calculate the effect that waste gas energy recovery has on lowering the impact of climate change. Greenhouse gases are emitted while burning the waste gas. However, a thorough study should include the production of the feedstock as well as the production of the infrastructure. A framework is developed to calculate the environmental impact of electricity production from waste gas with a life cycle approach. The present paper has a twofold purpose: to assess the climate change impact of generating electricity with blast furnace gas (BFG as a waste gas from the steel industry; and to establish a sensitivity assessment of the environmental implications of different allocation rules.

  15. Characteristics and properties of oil-well cements auditioned with blast furnace slag; Cementos petroleros con adicion de escoria de horno alto. Caracteristicas y propiedades

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, R.; Palacios, M.; Puertas, F.

    2011-07-01

    The present paper addresses the alkali activation of Portland cements containing blast furnace slag (20 and 30% by cement weight) with a view to the possible use of these materials in oil well construction. The hydration studies conducted showed that in cement/slag blends, the sodium silicate activator partially inhibited the dissolution of the silicate phases in the Portland cement, retarding cement hydration and reducing the precipitation of reaction products. Due to such partial inhibition, the cement/slag blends had significantly lower mechanical strength than Portland cements hydrated with water. {sup 2}9Si and {sup 2}7Al MAS NMR and BSE/EDX studies, in turn, showed that the CSH gel forming in the alkali-activated cement/slag pastes contained Al in tetrahedral positions and low Ca/Si ratios. (Author) 29 refs.

  16. Direct measurement of water self-diffusion in hardening blast furnace slag cement pastes by means of nuclear magnetic resonance techniques

    International Nuclear Information System (INIS)

    Recently, we have reported the unusual nuclear spin relaxation behavior of water in hardening blast furnace slag mixtures and suggested an explanation for the observed changes in the spin relaxation times based on diffusion effects in inner magnetic field gradients in the paste. Meanwhile, we have succeeded in measuring the self-diffusion coefficient of water in the hardening pastes directly by means of a special pulsed field gradient technique in which the effects of internal magnetic field gradients in a sample can be compensated for. Compared to water self-diffusion in ordinary cement materials, we find a much stronger decrease of the self-diffusion coefficient in the slag based cements. [copyright] 2001 American Institute of Physics

  17. Evaluation of mixtures of sugar cane bagasse and charcoal to inject in the blast furnace tuyeres; Avaliacao do uso de mistura de bagaco de cana-de-acucar com carvao vegetal para injecao nas ventaneiras do alto-forno

    Energy Technology Data Exchange (ETDEWEB)

    Brum, Janaina Solvelino; Silva, Thiago Lucas da; Reis, Eric Rafael dos; Assis, Paulo Santos [Universidade Federal de Ouro Preto (UFOP), MG (Brazil). Escola de Minas; Silveira, Natalia Carolina da [Universidade Federal de Ouro Preto (UFOP), MG (Brazil). Escola de Minas

    2009-11-01

    This paper shows the possibilities for using mixtures of sugar cane bagasse and charcoal for injecting into tuyeres of blast furnaces. Mixtures varying by 20 % from 0 till 100 % of charcoal in these have been done. The Bagasse can be used for energy generation to produce steam, as electrical main source, and now it is proposed a possible use to be considered in powder to be injected into blast furnaces.. The main advantage is under the point of view of Environment, but in some cases and time, can be a good opportunity to reduce the cost for producing hot metal. Based on this idea, it is proved that fossil fuels can be partially substituted using this biomass, giving the concept of zero consumption and generation of CO{sub 2}. That means reducing the Green House Effect. (author)

  18. Técnicas de caracterização para o desenvolvimento de massas de tamponamento para altos-fornos Characterization techniques for the development of blast furnace tap hole mixes

    Directory of Open Access Journals (Sweden)

    A. S. Ribeiro

    2013-03-01

    Full Text Available As massas de tamponamento para furos de corrida de altos-fornos são materiais refratários diretamente ligados a toda logística de produção de ferro gusa, pois é um dos agentes responsáveis pela estabilidade de vazamento destes equipamentos siderúrgicos. Durante a injeção da massa no interior do furo (na operação de tamponamento do forno, toda a escória e gusa remanescentes devem ser conduzidas para dentro do forno, a fim de que o furo seja completamente preenchido. Além disso, este produto deve recompor o cogumelo, que é a parte interior do cadinho do alto-forno, formada principalmente por massa de tamponamento antiga. No momento do vazamento do forno a massa de tamponamento, que foi injetada, curada e sinterizada no furo de corrida, deve apresentar relativa facilidade de perfuração por uma broca conduzida por máquina perfuratriz, proporcionando vazamento estável do forno. Desta forma, a massa de tamponamento é um material refratário monolítico de elevado nível tecnológico, com um conjunto de características que deve atender plenamente a exigências distintas. Ao mesmo tempo em que o produto deve apresentar determinado nível de densificação para suportar o agressivo ataque do gusa e da escória líquidos, deve proporcionar também relativa facilidade de perfuração, com um adequado nível de porosidade após sua sinterização. Além disso, este produto deve suportar condições extremamente elevadas de temperatura e pressão interna do alto-forno. Neste trabalho serão apresentadas técnicas de caracterização das massas de tamponamento para altos-fornos focando o balanço entre suas principais características. Entre estas, serão considerados aspectos ligados à adesão, usinabilidade e densificação do produto. No final será aplicada a metodologia AHP (Processo de Hierarquização Analítico para priorização e escolha da melhor formulação testada, considerando-se todos os parâmetros envolvidos.The hot metal production process is very dependent on the performance of the taphole mix, which directly influences the stability of the blast furnace. During the plugging operation the taphole mix must conduct all the metal and slag back into the furnace, thereby filling in and sealing the hole. Additionally it must also adhere to the old mix and recompose the so-called mushroom, which protects the inner part of the furnace hearth. Conversely, for the tapping operation, the mix, which has been cured and sintered, needs to be easily drilled in order to provide a stable and safe tapping? Therefore, the taphole mix is a complex and highly technological refractory product, designed to attend widely different demands. During operation it must be sintered and consolidated in order to attain good corrosion/erosion resistance against slag and hot metal, whereas for the tapping operation it must be soft enough to provide an easy drilling. Moreover, the taphole mix should resist to high temperatures and to the high pressure coming from the inner part of the blast furnace. In this work, a number of tests are presented in order to evaluate the performance of taphole mixes. The experiments were selected according to the most important demands that the mixes need to attain in actual operations: extrusion index, adhesion capacity, drilling resistance, mechanical strength, refractoriness, and others. The results of the tests were assessed according to the AHP (Analytical Hierarchy Process method, which allows for the selection of the best formulation considering all parameters involved.

  19. Técnicas de caracterização para o desenvolvimento de massas de tamponamento para altos-fornos / Characterization techniques for the development of blast furnace tap hole mixes

    Scientific Electronic Library Online (English)

    A. S., Ribeiro; G. F. B. Lenz e, Silva; H. C., Bassalo; P., Bonadia Neto; V. C., Pandolfelli.

    2013-03-01

    Full Text Available As massas de tamponamento para furos de corrida de altos-fornos são materiais refratários diretamente ligados a toda logística de produção de ferro gusa, pois é um dos agentes responsáveis pela estabilidade de vazamento destes equipamentos siderúrgicos. Durante a injeção da massa no interior do furo [...] (na operação de tamponamento do forno), toda a escória e gusa remanescentes devem ser conduzidas para dentro do forno, a fim de que o furo seja completamente preenchido. Além disso, este produto deve recompor o cogumelo, que é a parte interior do cadinho do alto-forno, formada principalmente por massa de tamponamento antiga. No momento do vazamento do forno a massa de tamponamento, que foi injetada, curada e sinterizada no furo de corrida, deve apresentar relativa facilidade de perfuração por uma broca conduzida por máquina perfuratriz, proporcionando vazamento estável do forno. Desta forma, a massa de tamponamento é um material refratário monolítico de elevado nível tecnológico, com um conjunto de características que deve atender plenamente a exigências distintas. Ao mesmo tempo em que o produto deve apresentar determinado nível de densificação para suportar o agressivo ataque do gusa e da escória líquidos, deve proporcionar também relativa facilidade de perfuração, com um adequado nível de porosidade após sua sinterização. Além disso, este produto deve suportar condições extremamente elevadas de temperatura e pressão interna do alto-forno. Neste trabalho serão apresentadas técnicas de caracterização das massas de tamponamento para altos-fornos focando o balanço entre suas principais características. Entre estas, serão considerados aspectos ligados à adesão, usinabilidade e densificação do produto. No final será aplicada a metodologia AHP (Processo de Hierarquização Analítico) para priorização e escolha da melhor formulação testada, considerando-se todos os parâmetros envolvidos. Abstract in english The hot metal production process is very dependent on the performance of the taphole mix, which directly influences the stability of the blast furnace. During the plugging operation the taphole mix must conduct all the metal and slag back into the furnace, thereby filling in and sealing the hole. Ad [...] ditionally it must also adhere to the old mix and recompose the so-called mushroom, which protects the inner part of the furnace hearth. Conversely, for the tapping operation, the mix, which has been cured and sintered, needs to be easily drilled in order to provide a stable and safe tapping? Therefore, the taphole mix is a complex and highly technological refractory product, designed to attend widely different demands. During operation it must be sintered and consolidated in order to attain good corrosion/erosion resistance against slag and hot metal, whereas for the tapping operation it must be soft enough to provide an easy drilling. Moreover, the taphole mix should resist to high temperatures and to the high pressure coming from the inner part of the blast furnace. In this work, a number of tests are presented in order to evaluate the performance of taphole mixes. The experiments were selected according to the most important demands that the mixes need to attain in actual operations: extrusion index, adhesion capacity, drilling resistance, mechanical strength, refractoriness, and others. The results of the tests were assessed according to the AHP (Analytical Hierarchy Process) method, which allows for the selection of the best formulation considering all parameters involved.

  20. Use of plastics in blast furnace processes: A contribution to ecologically and economically acceptable recycling of plastic waste; Kunststoffverwertung im Hochofen - ein Beitrag zum oekologischen und oekonomischen Recycling von Altkunststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Janz, J. [Stahlwerke Bremen GmbH (Germany)

    1996-12-31

    The use of plastics in blast furnace processes has a number of advantages. For one thing, existing facilities can be used with only slight reconstruction measures. Next, the blast furnace process does not necessarily require plastics and therefore is independent of the available plastics volume. Further, it has a high utilisation potential. For example, the Bremen blast furnace No. II has only 8 nozzles out of 32 which are suited for plastics, but it can utilize 70,000 t/a, which is more than 13 percent of the total plastics volume collected by DSD. Indepenent eco-balances have shown that there is no better technology on the market at the moment. (orig) [Deutsch] Mit der Kunststoffverwertung im Hochofen steht ein Verfahren zur Verfuegung, das sich gleich in mehrfacher Hinsicht vor der Konkurrenz auszeichnet. Im Gegensatz zu anderen Verwertungen wird eine bereits vorhandene Anlage genutzt, an der lediglich zusatzeinrichtungen benoetigt werden. Gleichzeitig wird abfallpolitische Flexibilitaet dadurch erreicht, dass der Hochofen nicht auf das Reduktionsmittel Kunststoff angewiesen ist. Von wesentlicher Bedeutung ist auch die hohe Verwertungskapazitaet eines Hochofens. Unabhaengige Oekobilanzen und eigene Messungen haben zweifelsfrei gezeigt, dass ein besseres Verfahren zur Zeit nicht auf dem Markt ist. (orig)

  1. Calculating the parameters of self-oscillations in the vertical combustion chamber of the blast-furnace air heater during unstable combustion

    Science.gov (United States)

    Basok, B. I.; Gotsulenko, V. V.

    2015-01-01

    A procedure for simplified calculation of the parameters of self-oscillations excited during unstable (vibrating) combustion in the vertical combustion chambers of blast-furnace air heaters is developed. The proposed procedure is based on an independent nonlinear dynamic system similar to the equations from the theory of a blade supercharger stalling and surging mode. The head characteristic considered in the blade supercharger stalling and surging theory determines the part of the supercharger drive rotation energy that is converted into the head developed by the supercharger. In the considered system, the supercharger head characteristic is replaced by the combustion chamber head characteristic. Being a function of flow rate, this characteristic describes the part of heat supplied to flow that is converted to the flow head. Unlike the supercharger head characteristic, which is determined by experiment, the combustion chamber head characteristic is determined by calculation, due to which it becomes much easier to calculate the parameters of self-oscillations according to the proposed procedure. In particular, an analysis of the periodic solutions of the obtained dynamic system made it possible to determine the pattern in which the amplitude of considered self-oscillations depends on the surge impedance of the vertical combustion chamber.

  2. [Solidification/Stabilization of Chromite Ore Processing Residue (COPR) Using Zero-Valent Iron and Lime-Activated Ground Granulated Blast Furnace Slag].

    Science.gov (United States)

    Chen, Zhong-lin; Li, Jin-chunzi; Wang, Bin-yuan; Fan, Lei-tao; Shen, Ji-min

    2015-08-01

    The solidification/stabilization (S/S) of chromite ore processing residue (COPR) was performed using zero-valent iron (ZVI) and lime-activated ground granulated blast furnace slag (GGBFS). The degree of Cr immobilization was evaluated using the leaching procedure, mineral composition analysis and morphology analysis. Semi-dynamic leaching tests were implemented to investigate the potential for reusing the final treatment product as a readily available construction material. The results showed that after reduction, all of the S/S treated COPR samples met the pollution control limit of bricks and building block products (Chinese standard HJ/T 301-2007) produced with COPR for total Cr (0.3 mg x L(-1)), the compressive strength of all the S/S samples could meet the compressive strength standard (15 MPa) for producing clay bricks, and Cr existed as the specie that bound to Fe/Mn oxides in the S/S samples. At the same time, all of the S/S treated specimens tested were suitable for utilization at certain levels. PMID:26592036

  3. The enhancement effect of pre-reduction using zero-valent iron on the solidification of chromite ore processing residue by blast furnace slag and calcium hydroxide.

    Science.gov (United States)

    Li, Jinchunzi; Chen, Zhonglin; Shen, Jimin; Wang, Binyuan; Fan, Leitao

    2015-09-01

    A bench scale study was performed to assess the effectiveness of the solidification of chromite ore processing residue (COPR) by blast furnace slag and calcium hydroxide, and investigate the enhancement effect of pre-reduction using zero-valent iron (ZVI) on the solidification treatment. The degree of Cr immobilization was evaluated using the Toxicity Characteristic Leaching Procedure (TCLP) as well as the solid waste-extraction procedure for leaching toxicity-sulfuric acid & nitric acid method (Chinese standard HJ/T299-2007). Strength tests and semi-dynamic leaching tests were implemented to investigate the potential for reusing the final treatment product as a readily available construction material. The experimental results showed that the performance of pre-reduction/solidification (S/S) was superior to that of solidification alone. After pre-reduction, all of the S/S treated COPR samples met the TCLP limit for total Cr (5 mg L(-1)), whereas the samples with a COPR content below 40% met the pollution control limit of bricks and building block products (Chinese standard HJ/T 301-2007) produced with COPR for total Cr (0.3 mg L(-1)). At the same time, all of the S/S treated specimens tested were suitable for utilization at certain levels. PMID:25929874

  4. Use of CaO as an activator for producing a price-competitive non-cement structural binder using ground granulated blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Sik; Jun, Yubin; Lee, Changha, E-mail: clee@unist.ac.kr; Oh, Jae Eun, E-mail: ohjaeeun@unist.ac.kr

    2013-12-15

    The use of calcium oxide (CaO) demonstrates a superior potential for the activation of ground granulated blast furnace slag (GGBFS), and it produces a higher mechanical strength than calcium hydroxide [Ca(OH){sub 2}]. The mechanical strength differences between CaO- and Ca(OH){sub 2}-activated GGBFS binders are explored using isothermal calorimetry, powder X-ray diffraction, thermogravimetric and differential thermal analysis (TGA and DTA) as well as compressive strength testing. Calcium silicate hydrate (C–S–H), Ca(OH){sub 2} and a hydrotalcite-like phase are found as reaction products in all samples. The TGA and DTA results indicate that the use of CaO produces more C–S–H, although this is not likely to be the primary cause of higher strength development in the CaO-activated GGBFS. Rather, other factors such as porosity may govern the strength at a higher order of magnitude. Significant reduction of Ca(OH){sub 2} occurs only with the use of Ca(OH){sub 2}, followed by the formation of carbonate (CaCO{sub 3}), indicating carbonation. -- Highlights: •CaO showed a better potential for the activation of GGBFS than Ca(OH){sub 2}. •Strength test, XRD, TGA/DTA and isothermal calorimetry are used. •C-S-H, Ca(OH){sub 2}, and a hydrotalcite-like phase are found in all samples. •The use of Ca(OH){sub 2} causes some degree of carbonation.

  5. Use of CaO as an activator for producing a price-competitive non-cement structural binder using ground granulated blast furnace slag

    International Nuclear Information System (INIS)

    The use of calcium oxide (CaO) demonstrates a superior potential for the activation of ground granulated blast furnace slag (GGBFS), and it produces a higher mechanical strength than calcium hydroxide [Ca(OH)2]. The mechanical strength differences between CaO- and Ca(OH)2-activated GGBFS binders are explored using isothermal calorimetry, powder X-ray diffraction, thermogravimetric and differential thermal analysis (TGA and DTA) as well as compressive strength testing. Calcium silicate hydrate (C–S–H), Ca(OH)2 and a hydrotalcite-like phase are found as reaction products in all samples. The TGA and DTA results indicate that the use of CaO produces more C–S–H, although this is not likely to be the primary cause of higher strength development in the CaO-activated GGBFS. Rather, other factors such as porosity may govern the strength at a higher order of magnitude. Significant reduction of Ca(OH)2 occurs only with the use of Ca(OH)2, followed by the formation of carbonate (CaCO3), indicating carbonation. -- Highlights: •CaO showed a better potential for the activation of GGBFS than Ca(OH)2. •Strength test, XRD, TGA/DTA and isothermal calorimetry are used. •C-S-H, Ca(OH)2, and a hydrotalcite-like phase are found in all samples. •The use of Ca(OH)2 causes some degree of carbonation

  6. Preparation of Slag Wool by Integrated Waste-Heat Recovery and Resource Recycling of Molten Blast Furnace Slags: From Fundamental to Industrial Application

    Directory of Open Access Journals (Sweden)

    Dawei Zhao

    2014-05-01

    Full Text Available The present paper investigated the process of the slag wool fabrication using high temperature blast furnace (BF slag modified by coal ash (CA. The liquidus temperature and viscosity of the slag system with different mass ratios of BF slag and CA were measured through an inner cylinder rotation method. The approximate mass ratio used to fabricate the slag wool was therefore determined and slag wool was then successfully prepared with a high-speed air injection method in the laboratory. The effect of mBF/m ratio, slag temperature for injection and air pressure on the preparation of slag wool was systematically investigated. The mechanical and thermal properties were also studied to confirm the long-term working conditions of the slag wool. An industry-scale slag wool production application was established. The energy consumption and the pollutant generation, were analyzed and compared with the traditional production method, which indicated a 70% reduction in energy consumption and a 90% pollution emission decrease.

  7. Speciation of Zn in blast furnace sludge from former sedimentation ponds using synchrotron X-ray diffraction, fluorescence, and absorption spectroscopy.

    Science.gov (United States)

    Kretzschmar, Ruben; Mansfeldt, Tim; Mandaliev, Petar N; Barmettler, Kurt; Marcus, Matthew A; Voegelin, Andreas

    2012-11-20

    Blast furnace sludge (BFS), an industrial waste generated in pig iron production, typically contains high contents of iron and various trace metals of environmental concern, including Zn, Pb, and Cd. The chemical speciation of these metals in BFS is largely unknown. Here, we used a combination of synchrotron X-ray diffraction, micro-X-ray fluorescence, and X-ray absorption spectroscopy at the Zn K-edge for solid-phase Zn speciation in 12 BFS samples collected on a former BFS sedimentation pond site. Additionally, one fresh BFS was analyzed for comparison. We identified five major types of Zn species in the BFS, which occurred in variable amounts: (1) Zn in the octahedral sheets of phyllosilicates, (2) Zn sulfide minerals (ZnS, sphalerite, or wurtzite), (3) Zn in a KZn-ferrocyanide phase (K(2)Zn(3)[Fe(CN)(6)](2)·9H(2)O), (4) hydrozincite (Zn(5)(OH)(6)(CO(3))(2)), and (5) tetrahedrally coordinated adsorbed Zn. The minerals franklinite (ZnFe(2)O(4)) and smithsonite (ZnCO(3)) were not detected, and zincite (ZnO) was detected only in traces. The contents of ZnS were positively correlated with the total S contents of the BFS. Similarly, the abundance of the KZn-ferrocyanide phase was closely correlated with the total CN contents, with the stoichiometry suggesting this as the main cyanide phase. This study provides the first quantitative Zn speciation in BFS deposits, which is of great relevance for environmental risk assessment, the development of new methods for recovering Zn and Fe from BFS, and potential applications of BFS as sorbent materials in wastewater treatment. PMID:23035937

  8. Influencia de la temperatura de curado: hidratación y resistencia de pastas de cemento con escoria / Influence of curing temperature: hydration and strength of cement paste with granulated blast furnace

    Scientific Electronic Library Online (English)

    C. C., Castellano; V. L., Bonavetti; E. F., Irassar.

    Full Text Available Actualmente son muy conocidos los beneficios tecnológicos, económicos y el menor impacto medioambiental que produce el empleo de adiciones minerales como reemplazo del cemento portland. Estas razones, han consolidado el uso de muchas adiciones como: escoria granulada de alto horno, ceniza volante, m [...] aterial calcáreo, humo de sílice, etc. En los últimos años, los cementos presentan un importante aumento en el contenido de las adiciones; el cual influye sobre la distribución de partículas, sobre la velocidad y naturaleza de las reacciones de hidratación y en consecuencia en su ganancia de resistencia. El presente trabajo evalúa la influencia de la temperatura en el curado (20, 40 y 60 ºC) de pastas con contenido variable de escoria granulada de alto horno (0 a 80 %) elaboradas con relación agua/material cementante de 0,40, sobre la resistencia mecánica. La evolución de la hidratación se estudió a través del análisis de los compuestos de hidratación por DRX y el contenido de agua no evaporable. La resistencia mecánica se evaluó empleando un diseño de experimentos central compuesto centrado. Los resultados obtenidos indican que a medida que la temperatura de curado aumenta con el incremento del contenido de escoria en el cemento mezcla, se aumentan la resistencia y el contenido de agua no evaporable, y disminuye la cantidad de hidróxido de calcio de la pasta. Abstract in english Nowadays it is well known that using blast furnace slag as partial replacements for Portland cement adds technological, economic and environmental benefits. Those are some of the reasons why cements containing several additions (blast furnace slag, fly ash, calcareous material, etc) are commonly use [...] d. In recent years, blended cements started to increase amounts of additions as replacement of Portland cement; in this regard these variations influence the rate and the mechanism of hydration and, consequently, strength development. The present work evaluated the effect of different curing temperatures (20, 40 and 60 ºC) on the mechanical strength of cement paste with different proportions of granulated blast-furnace slag (0 to 80 %). Pastes were prepared with water/cementitious material ratio (w/cm) equal to 0,4. The hydration evolution was determinated following the hydration products using XRD analysis and evaluated the content of non evaporable water. Mechanical strength was evaluated trough central composite experimental design. When granulated blast-furnace slag content increases with curing temperature, the results show that mechanical strength and non evaporable water increases, while the calcium hydroxide content decreases.

  9. Hopewell Furnace National Historic Site. Teacher's Guide.

    Science.gov (United States)

    National Park Service (Dept. of Interior), Washington, DC.

    This teacher's guide contains activities to use in conjunction with a site visit to the Hopewell Furnace National Historic Site (Elverson, Pennsylvania). The guide provides diagrams of the furnace, a cold-blast smelting operation, and the furnace operation. It presents a timeline of iron production from ancient times through contemporary times.…

  10. Characterisation of Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag cement-like composites for the immobilisation of sulfate bearing nuclear wastes

    Energy Technology Data Exchange (ETDEWEB)

    Mobasher, Neda; Bernal, Susan A.; Hussain, Oday H. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Apperley, David C. [Solid-State NMR Group, Department of Chemistry, Durham University, Durham DH1 3LE (United Kingdom); Kinoshita, Hajime [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Provis, John L., E-mail: j.provis@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2014-12-15

    Soluble sulfate ions in nuclear waste can have detrimental effects on cementitious wasteforms and disposal facilities based on Portland cement. As an alternative, Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composites are studied for immobilisation of sulfate-bearing nuclear wastes. Calcium aluminosilicate hydrate (C–A–S–H) with some barium substitution is the main binder phase, with barium also present in the low solubility salts BaSO{sub 4} and BaCO{sub 3}, along with Ba-substituted calcium sulfoaluminate hydrates, and a hydrotalcite-type layered double hydroxide. This reaction product assemblage indicates that Ba(OH){sub 2} and Na{sub 2}SO{sub 4} act as alkaline activators and control the reaction of the slag in addition to forming insoluble BaSO{sub 4}, and this restricts sulfate availability for further reaction as long as sufficient Ba(OH){sub 2} is added. An increased content of Ba(OH){sub 2} promotes a higher degree of reaction, and the formation of a highly cross-linked C–A–S–H gel. These Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composite binders could be effective in the immobilisation of sulfate-bearing nuclear wastes.

  11. Tests with blast furnace slag as bed material in a 12 MW waste fired BFB boiler; Fullskalefoersoek med Hyttsand som baeddmaterial i 12 MW avfallseldad BFB-panna

    Energy Technology Data Exchange (ETDEWEB)

    Eklund, Anders; Oehman, Marcus

    2004-11-01

    A full-scale trial has been performed at Saeverstaverket twin 12 MWth BFB boilers in Bollnaes using Hyttsand (a proprietary blast furnace slag) as bed material. The purpose has been to investigate if Hyttsand can be used as bed material in FB boilers for difficult types of fuels. Used fuel has been municipal waste, recovered wood fuel and different types of bio fuels. The test period was 19 days and nearly 100 tons of Hyttsand was used. The most important conclusions are: Good fluidisation can be achieved with Hyttsand as bed material. Hyttsand can fluidise without any changes in boiler settings. Hyttsand can also be mixed with Baskarpsand (a natural sand with over 90% SiO{sub 2}) and used as bed material without any negative changes to the boiler performance. Bed material make-up rate is reduced with up to 30 % when using Hyttsand compared to using Baskarpsand. Other conclusions are: Bed temperature increased slightly and bed temperature deviation decreased. Emissions was in general not affected, however emissions of SO{sub 2} increased slightly. More deposit containing more sulphur was formed on superheater surfaces when using Hyttsand. The increased amount of sulphur when using Hyttsand could be an effect of higher content of sulphur in the fuel or, which is more likely, that sulphur is released from Hyttsand and forms gaseous sulphurous gases. No significant change in produced amounts of fly-, cyclone- or bottom ash. Hyttsand and Baskarpsand had both similar coatings on their particles and similar agglomeration tendencies. There have been some start-up problems during the trials, including two more severe boiler disturbances, but most of these disturbances can be explained and avoided in the future. Previous investigations in laboratory scale using Hyttsand as bed material when firing different bio fuels have shown the advantage of Hyttsand with its higher resistance against a chemical reaction with alkali in the fuel ash compared to conventional bed materials, e.g. quartz. However, in these trials a waste fuel was used and all the analysed sintered samples clearly showed that melted glass was the main reason for de-fluidisation and bed sintering and not the reaction between alkali and the bed material. Therefore, the risk for bed sintering was not reduced when using Hyttsand in this boiler for this kind of waste fuel and the effect of glass in the bed was not studied in the laboratory tests. Hyttsand is today sold commercially with a high quantity available. The advantage of Hyttsand is a lower cost per kWh, despite a higher purchase price, due to the reduced bed consumption and that the cost for taking care less amount of used sand and ash also decreases. Also, Hyttsand opens the possibility of firing more difficult and less expensive fuels.

  12. Pulverized coal injection into pressurized furnace

    Energy Technology Data Exchange (ETDEWEB)

    Wakimoto, H.

    1985-01-01

    Tests of pulverised coal injection into an experimental blast furnace are briefly reported. The coal combustion characteristics are examined in relation to residence time, coal type and powder properties.

  13. Solid-fluid characteristics at the blast furnace hearth according to the nodal wear model (NWM); Caracteristicas solido-fluido en el crisol del horno alto segun el modelo de desgaste nodal (MDN)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.; Barbes, M. A.; Barbes, M. F.; Marinas, E.; Ayala, N.; Mochon, J.; Verdeja, L. F.; Garcia, F.

    2009-07-01

    The coke porosity is one of the most important variables that can affect the pig iron production and the lining corrosion. Up to now, the existing bibliography about lining corrosion always connects a deeper wear to an increase in the fluid flow (pig iron) at the blast furnace hearth. However, there is no evidence of any deterministic model that could link, from the theoretical point of view, the following variables: lining corrosion, porosity of dead coke and flow of pig iron at the hearth. Besides justifying the lining corrosion profiles, the Nodal Wear Model (NWM) can be an effective instrument to interpret the coke porosity and the pig iron speed rates that are generated inside the hearth. (Author) 23 refs.

  14. Influencia de la adición de escoria de alto horno en la penetración de los cloruros en el concreto / The influence of the blast furnace slag replacement on chloride penetration in concrete

    Scientific Electronic Library Online (English)

    Juan, Lizarazo Marriaga; Peter, Claisse.

    2011-08-01

    Full Text Available Debido a que en estructuras de concreto hechas con cemento Portland la penetración del ion cloruro es la principal causa de deterioro por corrosión del refuerzo, el estudio y prevención de los mecanismos que generan corrosión en el concreto son fuentes de constante investigación. En el presente artí [...] culo se presentan los resultados de una investigación analítica y experimental sobre la influencia de la adición de la escoria de alto horno en las propiedades que gobiernan los fenómenos de transporte iónico del concreto, especialmente los del ion cloruro. Las relaciones entre los coeficientes de difusión con la resistividad eléctrica, la carga pasada y la resistencia a la compresión, fueron evaluadas para mezclas con diferentes porcentajes de remplazo de escoria. De la misma forma, mediante un modelo computacional y un ensayo de migración eléctrica se obtuvieron los coeficientes intrínsecos de difusión, la porosidad, la capacidad de fijación de cloruros y la concentración química de la solución de poros. Los resultados obtenidos mostraron que la escoria aporta importantes beneficios en la penetración del ion cloruro, obteniéndose un concreto menos vulnerable a la corrosión. Abstract in english Corrosion of steel reinforcement due to chloride penetration is the greatest cause of durability problems in concrete; intense international research has been carried out to understand and avoid this. This paper summarises the results of a theoretical and experimental research programme investigatin [...] g the influence of blast furnace slag on chloride-related transport properties. The relationship between the apparent chloride diffusion coefficient, electrical resistivity and compressive strength was measured. Chloride, hydroxide, sodium and potassium’s intrinsic diffusion coefficients were obtained by using a computational model and an electrical migration test. The initial hydroxide composition of the pore solution, porosity and chloride binding capacity were also determined from the model. The results showed that blast furnace slag improved chloride penetration resistance, resulting in concrete which was less vulnerable to corrosion.

  15. Hopewell Furnace: A Pennsylvania Iron-Making Plantation. Teaching with Historic Places.

    Science.gov (United States)

    Koman, Rita G.

    The rhythmic noises of the turning water wheel and the roar of the furnace blast never stopped at Hopewell Furnace (Pennsylvania) during its years of operation (1771-1883). As long as the furnace was in blast, the ironworkers' jobs were safe. In case of trouble, they could escape to the woods, fields, and creeks of rural Pennsylvania. Now a…

  16. Granular flow

    DEFF Research Database (Denmark)

    Mitarai, Namiko; Nakanishi, Hiizu

    2012-01-01

    Granular material is a collection of macroscopic particles that are visible with naked eyes. The non-equilibrium nature of the granular materials makes their rheology quite different from that of molecular systems. In this minireview, we present the unique features of granular materials focusing ...... the shear flow of dry granular materials and granule-liquid mixture....

  17. Experimental research on the characteristics of softening and melting of iron ores as significant factor of influence on gas permeability of blast furnace charge

    Science.gov (United States)

    Branescu, E.; Blajan, A. O.; Constantin, N.

    2015-06-01

    It is widely accepted as a cohesive zone is directly influenced by softening and melting properties of iron ores, preparations (crowded, pellets, which represents about 90%, of the loads with metal furnace intake), or uncooked (raw ores ranked). Important results can be obtained through the study of behavior of ferrous materials at temperatures above 1000 ° C. Starting from research methods presented in the literature, this paper presents itself in carrying out their own laboratory experiments, conducted with the aim of analysing the softening and melting properties of sinter iron cores.

  18. Energetic analysis versus exergetic analysis of charcoal blast furnace of V and M do Brazil; Analise energetica versus analise exergetica do alto forno a carvao vegetal da V and M do Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Lis Nunes; Silva, Ricardo Junqueira [V e M do BRASIL S.A., Belo Horizonte, MG (Brazil); Franca, Geraldo Augusto Campolina; Lemos, Ricardo Jose Fernandes [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2011-12-21

    The energetic analysis is the traditional method of quantification of the energy used in an operation involving physical and chemical processes and transference and/or conversion of energy. Generally used through energetic balance that is based on the first law of thermodynamics to evaluate the energetic efficiency. This balance is used to determine and reduce the loss of energy. Although an energy balance does not provide information about the energy degradation or resources during a process and do not quantify the potential or quality of the energy fluxes and material that flow in a system and come out as products and losses. The exergetic analysis goes beyond the limitations of the first law of thermodynamics. The concept of exergy is based in the second law of thermodynamics. The objective of this paper is to compare the more suitable analysis method aiming the identification of the energy economy potentials and consequently the reduction in the emissions of the greenhouse gases, through the balance of mass, energy and exergy of the blast furnace 1 of V and M do Brazil. (author)

  19. Effects of H2O/Na2O molar ratio on the strength of alkaline activated ground blast furnace slag-ultrafine palm oil fuel ash based concrete

    International Nuclear Information System (INIS)

    Highlights: • Effects of H2O/Na2O on GBFS-POFA alkaline activated concrete are investigated. • High H2O/Na2O contents enhance dissolutions/workability at the expense of strength. • Lower H2O/Na2O molar ratios aid compressive strength of the products. • Increase in H2O/Na2O favours the reactivity of Ca and the products molecular bonds. • Low H2O/Na2O positively affects the microstructural density of the products. - Abstract: Effects of H2O/Na2O molar ratios (MRs) on the developed alkaline activated pozzolanic solid wastes (PMs)-ultrafine palm oil fuel ash (UPOFA) and ground blast furnace slag (GBFS)-were studied by using the constant mass of combined activators (10 M NaOHaq + Na2SiO3aq of silica-modulus (Ms = SiO2/Na2O) of 3.3).The free water content (FWC) expressed as FWC/(PMs) varied from 0.02 to 0.1 by mass while the total H2O/Na2O MRs ranged from 18.9 to 23.1 The findings revealed that increase in H2O/Na2O MRs negatively affects the strength but positively impact the mixture workability (consistency). The microstructural morphology examination using Scanning Electron Microscope coupled with Energy dispersive spectroscopy (SEM + EDS) reveals the contribution of H2O/Na2O MRs to the product nature, compactness, and the reactivity of Ca2+ and Al3+ while Fourier transform infra-red (FTIR) spectroscopy indicates that H2O/Na2O ratios contributed to the product amorphousity and carbonation process but sparingly affected its formed polymerized structural units (SiQn(mAl), n = 2 and 3)

  20. Kinetics of the reaction of iron blast furnace slag/hydrated lime sorbents with SO{sub 2} at low temperatures: effects of the presence of CO{sub 2}, O{sub 2}, and NOx

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.F.; Shih, S.M. [Industrial Technological Research Institute, Hsinchu (Taiwan)

    2009-09-15

    The effects of the presence of CO{sub 2}, O{sub 2}, and NOx in the flue gas on the kinetics of the sulfation of blast furnace slag/hydrated lime sorbents at low temperatures were studied using a differential fixed-bed reactor. When O{sub 2} and NOx were not present simultaneously, the reaction kinetics was about the same as that under the gas mixtures containing SO{sub 2}, H{sub 2}O, and N{sub 2} only, being affected mainly by the relative humidity. The sulfation of sorbents can be described by the surface coverage model and the model equations derived for the latter case. When both O{sub 2} and NOx, were present, the sulfation of sorbents was greatly enhanced, forming a great amount of sulfate in addition to sulfite. The surface coverage model is still valid in this case, but the model equations obtained show a more marked effect of relative humidity and negligible effects of SO{sub 2} concentration and temperature on the reaction. The effect of sorbent composition on the reaction kinetics was entirely represented by the effects of the initial specific surface area (S{sub g0}) and the Ca molar content (M{sup -1}) of sorbent. The initial conversion rate of sorbent increased linearly with increasing S{sub g0}, and the ultimate conversion increased linearly with increasing S{sub g0}M{sup -1}. The model equations obtained in this work are applicable to describe the kinetics of the sulfation of the sorbents in the low-temperature dry and semidry fine gas desulfurization processes either with an upstream NOx, removal unit or without.111

  1. Desempenho de telhas de escória de alto forno e fibras vegetais em protótipos de galpões Performance of tiles composed of blast furnace slag and vegetable fiber in prototype barns

    Directory of Open Access Journals (Sweden)

    Maristela N. da Conceição

    2008-10-01

    Full Text Available Busca-se, em todo o mundo, a substituição do cimento amianto por alternativas seguras para o ambiente e para a saúde do trabalhador, além de econômicas, razão por que o uso de fibras vegetais como aglomerado em países tropicais onde estes resíduos são abundantes, tem-se mostrado bastante viável. No presente experimento foram comparadas telhas de cimento amianto pintadas com tinta reflexiva, telhas cerâmicas e telhas compostas de uma matriz à base de cimento Portland CPII 32Z (ABNT NBR-5735, escória de alto-forno (EAF e sílica ativa, reforçadas com fibras de polpa celulósica de sisal (Agave sisalana. Utilizaram-se protótipos de galpões avícolas nos quais o calor produzido pelas aves foi simulado por lâmpadas incandescentes. Para caracterização do ambiente térmico lançou-se mão dos índices de conforto: ITU (índice de temperatura e umidade, ITGU (índice de temperatura de globo e umidade, CTR (carga térmica radiante e entalpia (H em que os resultados demonstraram que as telhas compostas apresentaram comportamento térmico semelhante ao das telhas cerâmicas, podendo ser utilizadas em substituição às telhas de cimento amianto.The substitution of cement asbestos by safer and equally economical alternatives has being searched for throughout the world. The usage of vegetal staple fiber as agglomerate in tropical countries where these residues are abundant has shown it self to be viable. In this study, roofing tiles fabricated with cement base Portland CPII 32Z (ABNT NBR-5735, blast furnace slag (EAF, active silica reinforced with cellulose pulp staple fibers of sisal (Agave sisalana were compared with cement asbestos roofing tiles with white paint and ceramic roofing tiles. Prototypes of poultry facilities were used and lamps simulated the heat produced by the birds. Indices ITU, ITGU, CTR and entalpy (H were employed for the characterization of the thermal atmospheric comfort and the results showed that the alternative roofing tiles were similar to the ceramic tiles and could be used as a substitute for asbestos roofing tiles.

  2. Variación de la Adherencia de las Armaduras Polarizadas Católicamente en Morteros de Cemento con Escoria Variation in Rebars Bond Strength in Cathodically Protected Mortar Specimens Containing Ground Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Jorge L Fernández

    2010-01-01

    Full Text Available El objetivo de este trabajo es explorar el efecto de diferentes sobrepotenciales aplicados al acero (-250 y -500 mV sobre la adherencia al mortero de cemento Portland adicionado con escoria granulada de alto horno (EGAH. Para realizar esta investigación se elaboraron probetas de mortero que fueron polarizadas católicamente, a los sobrepotenciales mencionados, durante 2 años en agua potable y cloruro de sodio 3%. Una vez finalizado el período de ensayo se determinó la tensión de adherencia de las barras de acero por medio de un ensayo de arrancamiento. Los resultados obtenidos muestran que las variaciones de adherencia son, en general, aleatorias; observándose ligeros aumentos de la adherencia y en algunos casos una disminución que no superó el 5%. La superficie de las barras de acero se observó por microscopía electrónica de barrido, comprobándose que la polarización modificó la película protectora.The objective of this research was to investigate the effect of two applied overpotentials (-250 and -500 mV on the adhesion of rebars in Portland cement mortars containing ground blast furnace slag. In order to carry out this investigation mortar slabs which were polarized, during 2 years, at the above mentioned overpotentials, in tap water and 3% sodium chloride, were made. After this exposure period, rebars bond strength was determined by a pull out test. As a general rule, bond strength variations were found to be random, observing slight bond strength increasing and in some cases a deceasing that did not exceed 5%. Rebars surface was also analyzed by scanning electron microscopy, finding that the protective layer on rebars changed as a consequence of the applied overpotentials.

  3. Compacting of fly dusts from cupola and electric arc furnace

    OpenAIRE

    Baricová, D.; P. Futáš; A. Pribulová; G. Fedorko; Demeter, P

    2012-01-01

    Recycling and utilization of dust waste is important not only from the point of view of its usage as an alternative source of raw materials, but regarding the environmental problems also. Dust emissions arise from thermal and chemical or physical processes and mechanical actions. Two kinds of fl y dusts from cupola furnaces (hot and cold blast cupola furnace) and fl y dust from electric arc furnace were used by experiments. They were pelletized only with addition of water and briquetted with ...

  4. New ironmaking process consisted of shaft type reduction furnace and cupola type melting furnace

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, T. (and others)

    1987-08-01

    Sumitomo Metal's SC process is described. Lump ore is reduced with gas from the second stage in a shaft furnace, and the resulting iron is melted in a second shaft packed with coke and supplied with oxygen and pulverized coal. Results of pilot plant tests are reported, a schematic design for a commercial plant is presented and a favourable technical comparison is made with the blast furnace route.

  5. Granular Thermodynamics

    OpenAIRE

    Shattuck, M. D.; Ingale, R. A.; Reis, Pedro Miguel

    2009-01-01

    We present experimental evidence for a strong analogy between quasi-2D uniform non-equilibrium steady states (NESS) of excited granular materials and equilibrium thermodynamics. Under isochoric conditions we find that the structure of granular NESS, as measured by the radial distribution function, the bond order parameter, and the distribution of Voronoi cells, is the same as that found in equilibrium simulations of hard disks. Three distinct states are found corresponding to a gas, a dense g...

  6. Mezcla ternaria de cemento Portland, escoria de alto horno y piedra caliza: Resistencia mecánica y durabilidad / Ternary mixture of Portland cement, blast furnace slag and limestone: Mechanical Strength and Durability

    Scientific Electronic Library Online (English)

    Jherson, E. Díaz; Silvia, R. Izquierdo; Ruby, Mejía de Gutiérrez; Marisol, Gordillo S.

    2013-12-01

    Full Text Available Los cementantes compuestos, basados en la sustitución parcial del cemento por otros minerales y/o subproductos industriales, surgen como una alternativa sostenible técnica y ambientalmente. Se basan en la introducción de dos o más adiciones para obtener mejores propiedades finales a través de los ef [...] ectos sinérgicos de sus componentes. El presente trabajo estudia el efecto en las propiedades de desempeño de un cemento portland cuando se incorpora adición de caliza (hasta 20%) y escoria siderúrgica de alto horno (hasta 30%), para generar una mezcla ternaria. Las propiedades evaluadas fueron resistencia a la compresión, absorción y porosidad, succión capilar, permeabilidad a cloruros, y resistencia química de los morteros expuestos a sulfatos. Los resultados indican que la resistencia mecánica a compresión de los cementos ternarios es hasta un 35% superior con relación al mortero de referencia y a su vez presentan menores coeficientes de succión capilar, confirmando la acción tanto de carácter físico como químico de los materiales de adición. Respecto a la resistencia al ataque por sulfatos el mejor comportamiento lo presento la mezcla con menor porcentaje de caliza; en este caso se determinaron los productos de reacción formados utilizando difracción de rayos X y microscopía electrónica de barrido. Abstract in english The blended cements based on partial replacement of cement by other minerals and / or industrial by-products arise as a technically and environmentally sustainable alternative. These cements are based on the introduction of two or more additions for better final properties through the synergistic ef [...] fects of its components. The present research examines the effect on the performance properties of Portland cement with addition of limestone (up to 20%) and blast furnace slag (up to 30%), to generate a ternary mixture. The compressive strength, absorption and porosity, capillary suction, chloride permeability, and chemical resistance of mortars exposed to sulfates were evaluated. The results show that the compressive strength of the cements ternary is up to 35% higher with respect to the reference mortar and in turn have lower coefficients of capillary suction, confirming the action of both physical and chemical nature of the materials addition. The best performance of resistance to sulfates attack was found in mixture with minor proportion of limestone. The characterization of the reaction products was performed using X-ray diffraction and scanning electron microscopy.

  7. Note on Fouilloux blast furnace puzzolanic cements

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1966-06-01

    Full Text Available Not availableDesde el 20 de septiembre de 1951, la Société des Matériaux de Construction de la Loisne, fabrica, bajo licencia de la patente francesa n.1.035.771 "Nouveaux Ciments" (Nuevos Cementos, de la que es titular M. Fouilloux, actualmente Presidente-Director general de la Sociedad, los cementos puzolano - metalúrgicos C. P-M. F. n. 1-160/300 y C. P.-M. F. n. 2-210/375; las ventas no han cesado de progresar y excedían de los 2 X 108 t en 1 de enero de 1965 (ver figura. Representan actualmente algo más del 45% de las ventas totales de la Sociedad.

  8. Forecasting quality of blast furnace coke

    Energy Technology Data Exchange (ETDEWEB)

    Filonenko, Yu.Ya.; Konev, N.L.; Drozdnik, I.D. (Lipetskii Politekhnicheskii Institut (USSR))

    1990-05-01

    Forecasting coke quality on the basis of parameters, such as plastic layer thickness, that describe caking power of coal mixtures (especially in the case of coals from different coal basins) is unreliable as there is no reliable correlation between plastic layer thickness and coke quality. Reliable formulae for coke quality prediction consider indices that characterize the temperature interval of coal plasticity, also taking into account incompatibility effects, coal rank and coal petrology (maceral types). Regression equations that accurately characterize effects of coal mixture properties on coke properties are developed for individual coke oven batteries in the USSR. The formulae use data banks in the USSR holding information on coal types supplied by individual mines and coal preparation plants. 11 refs.

  9. Material Systems for Blast-Energy Dissipation

    Energy Technology Data Exchange (ETDEWEB)

    James Schondel; Henry S. Chu

    2010-10-01

    Lightweight panels have been designed to protect buildings and vehicles from blast pressures by activating energy dissipation mechanisms under the influence of blast loading. Panels were fabricated which featured a variety of granular materials and hydraulic dissipative deformation mechanisms and the test articles were subjected to full-scale blast loading. The force time-histories transmitted by each technology were measured by a novel method that utilized inexpensive custom-designed force sensors. The array of tests revealed that granular materials can effectively dissipate blast energy if they are employed in a way that they easily crush and rearrange. Similarly, hydraulic dissipation can effectively dissipate energy if the panel features a high fraction of porosity and the panel encasement features low compressive stiffness.

  10. Granular physics

    Science.gov (United States)

    Valance, Alexandre; Louge, Michel

    2015-01-01

    Granular media play a major role in geophysics and industrial processes. Their interactions are complicated by relatively small-scale separation between individual particles and system size, by the presence of other interpenetrating phases such as water or air, by the large number of grains involved in realistic applications, and by the importance of microscopic contact forces, such as solid friction, which are challenging to measure or control. Yet significant progress has been made in the last two decades toward the understanding of granular media, thanks to the curiosity of physicists and engineers. This thematic issue gathers contributions from researchers dealing with diverse aspects of granular mechanics, from static assemblies to flowing suspensions, and from theory to natural phenomena. These review articles illustrate rather different approaches to these complicated systems.

  11. Granular Thermodynamics

    Science.gov (United States)

    Shattuck, M. D.; Ingale, R. A.; Reis, P. M.

    2009-06-01

    We present experimental evidence for a strong analogy between quasi-2D uniform non-equilibrium steady states (NESS) of excited granular materials and equilibrium thermodynamics. Under isochoric conditions we find that the structure of granular NESS, as measured by the radial distribution function, the bond order parameter, and the distribution of Voronoi cells, is the same as that found in equilibrium simulations of hard disks. Three distinct states are found corresponding to a gas, a dense gas, and a crystal. The dynamics of the dense gas is characterized by sub-diffusive behavior on intermediate time scales (caging). Under isobaric conditions we find a sharp first-order phase transition characterized by a discontinuous change in density and granular temperature as a function of excitation strength. The transition shows rate dependent hysteresis but is completely reversible if the excitation strength changes quasi-statically. All of these behaviors are analogous to equilibrium thermodynamics. The one difference is the velocity distributions, which are well described by P(c) = fMB[1+a2S2(c2)], in the range -2granular temperature, fmb is a Maxwell-Boltzmann and S2 is a second order Sonine polynomial. The single adjustable parameter, a2, is a function of the filling fraction, but not T. For |c|?2, P(c)?exp(-A×c-3/2) as observed in many other experiments.

  12. Aerodynamics of a promising vortex furnace design

    Science.gov (United States)

    Anufriev, I. S.; Strizhak, P. A.; Chernetskii, M. Yu.; Shadrin, E. Yu.; Sharypov, O. V.

    2015-08-01

    The aerodynamics of a promising vortex furnace design with secondary top blasting has been studied. Flow velocity fields have been measured in an isothermal laboratory model of the furnace using a digital tracer imaging (particle image velocimetry) technique. Three-dimensional diagnostics of flow structure in the combustion chamber has been carried out by the method of laser Doppler anemometry. Processing of the obtained data using the criterion of "minimum total pressure" has been used to visualize the spatial structure of the vortex core.

  13. Vitrification furnace

    International Nuclear Information System (INIS)

    Radioactive liquid wastes formed in a nuclear power plant are mixed with liquid glass in a vitrification furnace in a liquid waste processing facility, and then they are filled into a glass solidification vessel and solidified. A reflection plate is disposed at a predetermined position of a lower portion of a flow down nozzle disposed at the bottom of a main body of the vitrification furnace. The flowing down nozzle is heated by heating coils, and liquid glass is started to be flown down from the flowing down nozzle. In this case, radiation heat generated by the heating coils is reflected to the lower end of the flow down nozzle by the reflection plate. Temperature at the lower end of the flowing down nozzle is made substantially uniform in the circumferential direction, and the viscosity of the liquid glass flowing down the flowing down nozzle is not varied substantially in the circumferential direction. As a result, the liquid glass flowing down the flow down nozzle is not curved but fallen substantially vertically. (I.N.)

  14. Melting furnace

    International Nuclear Information System (INIS)

    Fibrous molding products (glass cartridge) and high level liquid wastes are supplied to raw material transferring pipes, and the fibrous molding products in a state impregnated with the liquid wastes are supplied to a melting furnace main body. The fibrous molding products and the liquid wastes transferred along the inside of the raw material transferring pipes are heated by a heating means and volatile matters are evaporated. In this case, volatile metals such as ruthenium are also gasified. A purge air supply system is operated to cause air stream flowing from upstream to downstream in the raw material transferring pipes, so that air and steams in the vicinity of the fibrous molding products are sent to a gas phase portion of the furnace main body. Then, the mixed gases are withdrawn into an off-gas processing system. With such procedures, useful metals such as ruthenium which tends to be gasified can efficiently be recovered without being sent to molten glass. (I.N.)

  15. Granular matter

    Science.gov (United States)

    Herrmann, H. J.

    2002-10-01

    This is an introductory course into some aspects of the physics of granular materials. Three theoretical questions are looked into more detail corresponding to the 3 h of the course: I present some statistical models to describe the shape of a heap under impact and present a way to calculate the angle of repose from the first principle. The second part contains the theoretical framework of a hydrodynamic description of fluid sand and the calculation of transport properties using kinetic gas theory. Cooling and clustering are given as example and counter-example. The last part focusses on packings and in particular on lattice models for compaction dynamics.

  16. Avaliação das possibilidades de escórias de siderurgia como corretivos da acidez do solo Evaluation of blast furnace slags as correctives for soil acidity

    Directory of Open Access Journals (Sweden)

    Antônio Carlos Pimentel Wutke

    1962-01-01

    Full Text Available No presente trabalho são apresentados os resultados obtidos em um ensaio de competição entre materiais corretivos, conduzido em vasos de Mitscherlich. Objetivou-se, principalmente, avaliar as possibilidades de dois tipos de escórias de siderurgia para substituir os corretivos usuais na agricultura. Foram comparados um calcário dolomítico cristalino, um calcário altamente cálcico, um material cálcico proveniente dos sambaquis do Litoral Sul paulista, uma escória de altos fornos a coque, produzida em Volta Redonda, e uma escória originária da produção de aços pelo processo Martin-Siemens básico, obtida em São Caetano. Os materiais corretivos foram comparados sempre em presença de adubação com NPK, feita em solução e na forma de drogas puras. Constaram, ainda, da experiência, um tratamento testemunha e outro com NPK, sem calagem. A planta indicadora utilizada foi a soja, Glycine max (L. Merril, variedade "Abura". No final do ensaio, além da colheita das sementes de soja, retiraram-se amostras de terra de todos os vasos, para determinações de seus índices pH e dos teores de H+ + AL+3 trocável. Com relação ao poder de neutralização da acidez do solo, revelaram-se mais eficiente o calcário dolomítico, o cálcico e o sambaqui Com eficiência intermediária colocou-se a escória de São Caetano e. em último lugar, a escória de Volta Redonda. As produções das sementes de soja, todavia, não confirmaram êstes resultados, uma vez que as diferenças, entre os tratamentos com corretivos não foram estatisticamente significativas. Moagem mais severa do que a utilizada neste ensaio possivelmente elevará a eficiência das duas escórias, como corretivos da acidez do solo. Com relação às suas influências sôbre a produção, avaliadas nas condições do ensaio, não há necessidade de se apurar mais o seu grau de moagem, a nao ser para atender às exigências legais, que disciplinam o comércio de adubos e corretivos.This paper presents preliminary results obtained in a greenhouse test in which blast furnace slags and other lime materials were compared as soil correctives. Comparisons were made between dolomitic limestone, calcitic limestone, oyster-shell lime, slag from iron production and slag from steel production by the Martin-Siemens basic procedure. These materials were compared at two different rates. General application of NPK fertilizers was made and the control treatment received no lime. The soybean variety Abura (Glycine max (L. Merril was utilized as an indicator plant; four plants were grown in each pot. Final grain production was measured and soil samples were collected, from the pots, in order to check the pH and exchangeable acidity (H+ + Al+3. The results obtained showed that under the conditions of the test, the dolomitic limestone, the calcitic limestone and the oyster-shell lime were all equally efficient in their corrective effect. The slag from steel production showed an intermediary effect, while the slag from iron prodution appeared to be the least efficient. The grain yield from these treatments did not presente any statistically significant difference. The actual grinding of the materials used in the experiment seemed satisfactory. A finer grinding is not deemed necessary unless it is required by the legislation covering the commerce of soil correctives.

  17. Development and start up of a co-injection system of coal tar/natural gas in blast furnace no. 4; Desarrollo y puesta en operacion de un sistema de co-inyeccion de alquitran/gas natural en el alto horno no. 4

    Energy Technology Data Exchange (ETDEWEB)

    Falcon Rodriguez, Manuel I.; Mata Esparza, Hector Rolando; Arevalo Ballesteros, Gerardo [Altos Hornos de Mexico S. A., Coahuila (Mexico)

    1993-12-31

    The crisis has attracted the world`s attention on the need for energy conservation and the development in a greater extent the utilization of carbon base fuels and other energy sources (nuclear energy). Being a blast furnace, not only an energy consumer but also an energy producer, the greatest contribution to the pig iron cost is the energy needed to melt and reduce to metallic state the iron ores, this energy is mainly derived from coke. The dependence on coal via the coking plant to produce first fusion iron is incremented day after day as a result of the high levels of production. Altos Hornos de Mexico (AHMSA), contemplated within its strategic plan, the reduction in the production of its coking plants derived from the natural aging of its furnaces, consequently the shortage of coke for productions higher than 2.6 MMT of pig iron is pending. The injection of fuels into a blast furnace through its nozzles is a technology used for the diminishing the coke consumption of coke, its use implies a change in the philosophy of the blast furnace operation, and is currently employed in most of the blast furnaces of the world. AHMSA taking advantage of coal tar production (approx. 130 tons/day) in its coking plants decided the design and put into operation a co-injection system of coal tar and natural gas. The activities tending to carry out this project were initiated on April 1993, performing all of them with its own resources, completing them on July 18, 1993, day on which the injection of coal tar/natural gas in blast furnace No. 4 in a stable form. To date (October 1993), the coal tar injection has been increased up to 36 kg/ton of pig iron. During the injection periods, the presence of operational, mechanical and instrumentation problems have not been an obstacle for the evolution on the injection, fulfilling its function of substituting coke in a replacing relationship of 1:1, i.e. 1 kg of coal tar per each kg of coke, without affecting the product quality. [Espanol] La crisis de energia ha acaparado la atencion mundial sobre la necesidad de conservar la energia y desarrollar en un mayor grado el uso de combustibles en base a carbon y otras fuentes de energia (energia nuclear). Siendo el alto horno no solo un consumidor de energia sino tambien un generador de la misma (gas alto horno), la mayor contribucion al costo de arrabio es la energia necesaria para fundir y reducir al estado metalico los minerales de fierro, dicha energia en su mayoria proviene del coque. La dependencia del carbon via planta de coque para producir hierro de primera funcion se incrementa cada dia como resultado de los altos niveles de produccion. Altos Hornos de Mexico (AHMSA), contemplo dentro de su plan estrategico la disminucion de produccion de sus plantas coquizadoras derivada del envejecimiento natural de sus hornos, consecuencia de esto se hace inminente el deficit de coque para producciones superiores a 2.6 MMt de arrabio. La inyeccion de combustibles al alto horno a traves de sus toberas es una tecnologia para disminuir el consumo de coque, su uso implica un cambio en la filosofia de operacion del alto horno y es actualmente utilizada por la mayoria de los altos hornos del mundo. AHMSA aprovechando la generacion de alquitran (aprox. 130 ton/dia) de sus plantas coquizadoras decide disenar y poner en operacion un sistema de co-inyeccion de alquitran y gas natural, las actividades encaminadas a realizar lo anterior dieron inicio el mes de abril de 1993 efectuandose todas ellas con recursos propios de la empresa, finalizando el dia 18 de julio de 1993 dia en el cual se inicio la co-inyeccion de alquitran/gas natural en el Alto Horno no. 4 en forma estable. A la fecha (octubre 1993), la inyeccion de alquitran se ha incrementado hasta 36 kg/t. de arrabio, durante los periodos de inyeccion, la presencia de problemas operativos, mecanicos y de instrumentacion no han sido obstaculo para la evolucion de la inyeccion cumpliendo su funcion de sustituir al coque en una relacion de reemplazo de 1:1, es decir, 1 kg de alquitran por cada kg de coque sin afectar la calidad del producto.

  18. Granular parakeratosis.

    Science.gov (United States)

    Martín, José M; Pinazo, Isabel; Molina, Inmaculada; Monteagudo, Carlos; Villalón, Guillermo; Jordá, Esperanza

    2008-07-01

    A healthy 62-year-old woman was referred to our dermatology department with a 1-month history of a pruritic axillary eruption. On examination, multiple erythematous and brownish hyperkeratotic papules were seen in both axillae. Some of these lesions coalesced into plaques, with small areas of sparing, and a background erythematous color was also found in the axillary vaults (Fig. 1). There was no involvement of other intertriginous sites and there were no associated systemic symptoms. The patient was not obese. The patient had removed the hair from her axillae with wax 3 weeks before the development of the eruption. Moreover, she had changed her antiperspirant 1 week before the onset of the lesions. A cutaneous biopsy for histologic analysis was performed. Histologically, the stratum corneum was thickened, with persistent nuclei together with countless small basophilic granules. The granular layer was preserved and, in some areas, hypergranulosis was found (Fig. 2). These findings were characteristic of granular parakeratosis. The cutaneous lesions resolved completely after 1 week of treatment with topical betamethasone dipropionate and gentamicin sulfate (twice daily). The patient was urged to discontinue her use of deodorants. PMID:18613879

  19. High temperature solar furnace: current applications and future potential

    International Nuclear Information System (INIS)

    The high temperature solar furnace can offer great opportunities for the production of many types of products worldwide, but recent advances in this technology have been limited to metal reduction. The production of semiconductors, which are utilized to a great extent in the electronic industry, is a viable option for this technology that has been overlooked. Especially where sand and sunlight are plentiful (countries that surround the equator), silicon chips produced with a solar furnace can have great economical value. This paper describes current and potential solar furnace technologies. The components of the solar furnace are described, as well as metal reduction processes including zinc and aluminum production. The viability of silicon chip production is also examined. The possibilities for other product development using an extremely (up to 10,000 deg C) high temperature solar furnace are also discussed. Economically, the benefits of solar furnaces are great, with only high initial start-up costs and little operation costs. Metal reduction processes can also be enhanced with high temperature solar furnaces in that plugging problems are eliminated. By replacing conventional furnaces, such as blast and electric arc furnaces, with a high temperature solar furnace, CO2 emissions and energy consumption can be greatly reduced, which will bring in added dividends to the society. (Author)

  20. Waste and dust utilisation in shaft furnaces

    Directory of Open Access Journals (Sweden)

    Senk, D.

    2005-12-01

    Full Text Available Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilized e.g. in agglomeration processes (sintering, pelletizing or briquetting and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverized coal (PC has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.

    Los residuos y polvos de filtro provenientes de la industria siderúrgica, de la obtención de metales no ferrosos y de otras industrias, pueden ser utilizados, por ejemplo, en procesos de aglomeración como sintetizado, peletizado o briqueteado. En su caso, estos pueden ser inyectados en los hornos de cuba. Este artículo se enfoca a la inyección de estos materiales en los hornos de cuba. El comportamiento de la combustión y reducción de los polvos ricos en hierro y carbono y también lodos que contienen plomo, zinc y compuestos alcalinos y otros residuos con o sin carbón pulverizado (CP fue examinado, cuando se inyectaron en hornos de cuba. Los siguientes hornos de cuba fueron examinados: Horno alto, cubilote, OxiCup y horno de cuba Imperial Smelting. Las investigaciones se llevaron a cabo a escala de laboratorio e industrial. Algunos residuos y polvos bajo ciertas condiciones, no sólo pueden ser reciclados, sino también mejoran la eficiencia de combustión en las toberas, la operación y productividad del horno.

  1. Miringitis granular

    Directory of Open Access Journals (Sweden)

    Laura Espinosa Morett

    2012-01-01

    Full Text Available La miringitis granular es una enfermedad inflamatoria de la membrana timpánica, poco reconocida y poco usual. Se define clínicamente como una entidad caracterizada por desepitelización de la capa epitelial de la membrana timpánica, con tejido de granulación en la capa fibrosa de la misma. Es un proceso limitado exclusivamente a la membrana timpánica y a la piel adyacente del conducto auditivo externo, sin afectación del oído medio. Sus síntomas principales son otorrea crónica y recurrente, plenitud ótica, hipoacusia y ¿rara vez¿ otalgia. Se comunica el caso de una paciente manejada con ácido bórico para el alivio de su padecimiento y se hace una revisión de la bibliografía médica, se propone un algoritmo de abordaje diagnóstico y terapéutico de esta entidad.

  2. Blast management

    OpenAIRE

    Shouraki, Mohammad Kargar; Naserkheil, Ali Asghar

    2011-01-01

    Blast Management (BM) is composed of the combination of human resources management (HRM) principles and concepts and various methods of quality management (QM) with a financial approach. BM is made up of three aspects: hard, soft and concept and BLAST means an explosive shift in organization's mindset and thought and rapid action against it. The first aspect, hard, includes a set of managerial toots and philosophies to improve the quality and productivity with a financial approach.

  3. Survey on granularity clustering.

    Science.gov (United States)

    Ding, Shifei; Du, Mingjing; Zhu, Hong

    2015-12-01

    With the rapid development of uncertain artificial intelligent and the arrival of big data era, conventional clustering analysis and granular computing fail to satisfy the requirements of intelligent information processing in this new case. There is the essential relationship between granular computing and clustering analysis, so some researchers try to combine granular computing with clustering analysis. In the idea of granularity, the researchers expand the researches in clustering analysis and look for the best clustering results with the help of the basic theories and methods of granular computing. Granularity clustering method which is proposed and studied has attracted more and more attention. This paper firstly summarizes the background of granularity clustering and the intrinsic connection between granular computing and clustering analysis, and then mainly reviews the research status and various methods of granularity clustering. Finally, we analyze existing problem and propose further research. PMID:26557926

  4. Radiotracer glass furnaces investigations

    International Nuclear Information System (INIS)

    The methodology and results of radiotracer investigation of a furnace for flat glass production are presented. Lanthanum oxide activated in a nuclear reactor was used as glass tracer. The dynamic characteristic of the furnace and principal parameters of its operation were determined. The glass flow in the furnace was proposed. (author). 4 refs, 15 figs

  5. Blast Waves

    CERN Document Server

    Needham, Charles E

    2010-01-01

    The primary purpose of this text is to document many of the lessons that have been learned during the author’s more than forty years in the field of blast and shock. The writing therefore takes on an historical perspective, in some sense, because it follows the author’s experience. The book deals with blast waves propagating in fluids or materials that can be treated as fluids. It begins by distinguishing between blast waves and the more general category of shock waves. It then examines several ways of generating blast waves, considering the propagation of blast waves in one, two and three dimensions as well as through the real atmosphere. One section treats the propagation of shocks in layered gases in a more detailed manner. The book also details the interaction of shock waves with structures in particular reflections, progressing from simple to complex geometries, including planar structures, two-dimensional structures such as ramps or wedges, reflections from heights of burst, and three-dimensional st...

  6. Heat treatment furnace

    Energy Technology Data Exchange (ETDEWEB)

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  7. Granular temperature field of monodisperse granular flows

    Science.gov (United States)

    Gollin, Devis; Bowman, Elisabeth; Shepley, Paul

    2015-04-01

    For dry granular flows as well as solid-fluid mixtures such as debris avalanches, the momentum transfer is carried by frictional and collisional stresses. The latter may be described by the granular temperature, which provides a measure of the energy contained within the fluctuating nature of the granular motion. Thus, granular temperature can be used as a valuable means to infer the ability of a granular system to flow. Granular materials are known for the difficulties they pose in obtaining accurate microscale laboratory measurements. This is why many theories, such as the kinetic theory of granular gases, are primarily compared to numerical simulations. However, thanks to recent advancements in optical techniques along with high-speed recording systems, experimentalists are now able to obtain robust measurements of granular temperature. At present, the role of granular temperature in granular flows still entails conjecture. As a consequence, it is extremely important to provide experimental data against which theories and simulations can be judged. This investigation focuses on dry granular flows of sand and spherical beads performed on a simple inclined chute geometry. Fluctuation velocity, granular temperature and velocity patterns are obtained by means of particle image velocimetry (PIV). Flow behaviour is probed for different spatial (interrogation sizes) and temporal (frame rates) resolutions. Through the variation of these parameters an attempt to demonstrate the consistency of the degree of unsteadiness within the flow is made. In many studies a uniform stationary flow state is usually sought or preferably assumed for the simplicity it provides in the calculations. If one tries to measure microscale fields such as granular temperature, this assumption may be inappropriate. Thus, a proper definition of the flow regime should be made in order to estimate the correct flow properties. In addition, PIV analysis is compared against particle tracking velocimetry (PTV). This alternative technique provides high-accuracy measurements and allows individual flow tracer particles to be tracked. In comparison, PIV provides exhaustive analyses although some limitations exist. The interrogation size plays an important role in determining the achievable spatial resolution of the flow. There is a limit on how large or small this region can be for adequate measurements. A further limitation is encountered when velocity gradients are presents which apt to bias the displacement estimate. Ultimately, the above techniques and analysis will be applied to 3D polydisperse granular systems. This is extremely valuable to gain a more complete understanding and move towards more realistic flows. The overall aim of this study lies in obtaining a clearer understanding of the micromechanical processes governing granular flows and improving the modelling of debris avalanche hazards.

  8. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME V. ELECTRIC ARC FURNACE, MANUAL OF PRACTICE

    Science.gov (United States)

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  9. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME IV. OPEN HEARTH FURNACE, MANUAL OF PRACTICE

    Science.gov (United States)

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  10. Blast Injuries

    Science.gov (United States)

    ... DoD Worldwide Numbers for TBI Education Resources Training & Events Research Current DVBIC Studies DVBIC Publications Concussion Literature Information Papers Study Manuals DVBIC Locations Service Members & Veterans Family & Caregivers Medical Providers Blast Injuries (U.S. Army photo by Sgt. ...

  11. Electromelt furnace evaluation

    International Nuclear Information System (INIS)

    An electromelt furnace was designed, built, and operated at the Idaho National Engineering Laboratory to demonstrate the suitability of this equipment for large-scale processing of radioactive wastes in iron-enriched basalt. Several typical waste compositions were melted and cast. The furnace was disassembled and the components evaluated. Calcines and fluorides attacked the furnace lining, unoxidized metals accumulated under the slag, and electrode attrition was high

  12. Direct current arc furnace

    Energy Technology Data Exchange (ETDEWEB)

    Hua, A.; Ju, X.Y. [Xian Electric Furnace Institute of China (China); Li, Z.C. [Xian Electromagnetic Machine Factory of China (China)

    1992-12-31

    The performance of the WTD type 20 t -9 MVA DC arc furnace which has operated at one of China`s steel plants since 1985 was discussed. The operational advantages of DC furnaces are: (1) Low flicker effect, since the double electrode DC arc furnaces can reduce the voltage flicker by one-half, (2) reduced noise emission, hence increased arc stability, (3) lower electrode consumption, which is the principal objective objective of the AC to DC furnace conversion, and (4) reduced energy consumption, with net energy savings estimated at about 13 percent. 3 refs., 1 tab., 3 figs.

  13. On Granular Knowledge Structures

    CERN Document Server

    Zeng, Yi

    2008-01-01

    Knowledge plays a central role in human and artificial intelligence. One of the key characteristics of knowledge is its structured organization. Knowledge can be and should be presented in multiple levels and multiple views to meet people's needs in different levels of granularities and from different perspectives. In this paper, we stand on the view point of granular computing and provide our understanding on multi-level and multi-view of knowledge through granular knowledge structures (GKS). Representation of granular knowledge structures, operations for building granular knowledge structures and how to use them are investigated. As an illustration, we provide some examples through results from an analysis of proceeding papers. Results show that granular knowledge structures could help users get better understanding of the knowledge source from set theoretical, logical and visual point of views. One may consider using them to meet specific needs or solve certain kinds of problems.

  14. Anaerobic granular sludge.

    OpenAIRE

    Alphenaar, A.

    1994-01-01

    Many UASB reactors are designed in such a fashion that the presence of granular sludge is necessary for a proper purification process. For achieving an optimum wastewater purification with such reactors, knowledge of the factors that determine the growth, retention and disintegration of anaerobic granular sludge is essential. The present research focused on gaining more insight in the factors determining the growth and quality of anaerobic granular sludge.For determining the total available p...

  15. Wet Granular Materials

    CERN Document Server

    Mitarai, N; Mitarai, Namiko; Nori, Franco

    2006-01-01

    Most studies on granular physics have focused on dry granular media, with no liquids between the grains. However, in geology and many real world applications (e.g., food processing, pharmaceuticals, ceramics, civil engineering, constructions, and many industrial applications), liquid is present between the grains. This produces inter-grain cohesion and drastically modifies the mechanical properties of the granular media (e.g., the surface angle can be larger than 90 degrees). Here we present a review of the mechanical properties of wet granular media, with particular emphasis on the effect of cohesion. We also list several open problems that might motivate future studies in this exciting but mostly unexplored field.

  16. IRON ORE SINTER PRODUCTION USING ELECTRIC ARC FURNACE DUST AS RAW MATERIAL

    Directory of Open Access Journals (Sweden)

    Victor Bridi Telles

    2013-03-01

    Full Text Available The steel production through Electric Arc Furnaces (EAF generates approximately 15% to 20% of Electric Arc Furnace Dust (EAFD. This waste is considered dangerous due to the presence of metals as lead and cadmium that leach in contact with water. Because of this, the EAFD recycling becomes an alternative to diminish the costs with landfills and environmental harms caused by the waste. The iron ore sintering is a process that reuses most part of powders generated by the steelmaking. However the EAFD is not reused in this process because it contains zinc. The zinc is highly detrimental inside blast furnaces causing heavy crusts and affecting the thermodynamic equilibrium of the process. Therefore, this work studies the EAFD reuse in the iron ore sintering process to produce iron ore sinter with zinc contents between the limits established for blast furnaces.

  17. Calculations in furnace technology

    CERN Document Server

    Davies, Clive; Hopkins, DW; Owen, WS

    2013-01-01

    Calculations in Furnace Technology presents the theoretical and practical aspects of furnace technology. This book provides information pertinent to the development, application, and efficiency of furnace technology. Organized into eight chapters, this book begins with an overview of the exothermic reactions that occur when carbon, hydrogen, and sulfur are burned to release the energy available in the fuel. This text then evaluates the efficiencies to measure the quantity of fuel used, of flue gases leaving the plant, of air entering, and the heat lost to the surroundings. Other chapters consi

  18. Continuous ring furnaces

    Energy Technology Data Exchange (ETDEWEB)

    De Stefani, G.; Genevois, J.L.; Paolo, P.

    1981-01-06

    A smoke conducting apparatus for use particularly with continuous ring furnaces (e.g., Hoffman furnaces) wherein each furnace chamber is connected to the smoke channel, the latter being a metal pipe inclined slightly from horizontal and provided with one or more traps along the length of its bottom surface, each trap containing a removable receptacle, and heating means being disposed along the bottom of the channel to fluidize tarry deposits of combustion products so that such deposits will flow by gravity into the removable receptacle.

  19. Biomedical Informatics and Granularity

    Directory of Open Access Journals (Sweden)

    Daniel D. Novotny

    2006-04-01

    Full Text Available An explicit formal-ontological representation of entities existing at multiple levels of granularity is an urgent requirement for biomedical information processing. We discuss some fundamental principles which can form a basis for such a representation. We also comment on some of the implicit treatments of granularity in currently available ontologies and terminologies (GO, FMA, SNOMED CT.

  20. Cystic Granular Cell Ameloblastoma

    OpenAIRE

    Thillaikarasi, Rathnavel; Balaji, Jayaram; Gupta, Bhawna; Ilayarja, Vadivel; Vani, Nandimandalam Venkata; Vidula, Balachander; Saravanan, Balasubramaniam; Ponniah, Irulandy

    2010-01-01

    Ameloblastoma is a locally aggressive benign epithelial odontogenic tumor, while unicystic ameloblastoma is a relatively less aggressive variant. Although rare in unicystic or cystic ameloblastoma, granular cell change in ameloblastoma is a recognized phenomenon. The purpose of the present article is to report a case of cystic granular cell ameloblastoma in 34-year old female.

  1. ENERGY STAR Certified Furnaces

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 4.0 ENERGY STAR Program Requirements for Furnaces that are effective as of February 1,...

  2. Compacting of fly dusts from cupola and electric arc furnace

    Directory of Open Access Journals (Sweden)

    D. Baricová

    2012-01-01

    Full Text Available Recycling and utilization of dust waste is important not only from the point of view of its usage as an alternative source of raw materials, but regarding the environmental problems also. Dust emissions arise from thermal and chemical or physical processes and mechanical actions. Two kinds of fl y dusts from cupola furnaces (hot and cold blast cupola furnace and fl y dust from electric arc furnace were used by experiments. They were pelletized only with addition of water and briquetted with diff erent addition of water glass, bentonite and cement. Quality of briquettes was tested by compression – strength test and by break down test in green state, after drying and afterstoring (1 month.

  3. Investigation on the Potentials of Cupola Furnace Slag in Concrete

    Directory of Open Access Journals (Sweden)

    Stephen Adeyemi Alabi

    2013-12-01

    Full Text Available The compressive strength of the concrete designed using blast cupola furnace slag and granulated cupola slag as a coarse aggregate and partial replacement for cement was investigated. A series of experimental studies were conducted involve concrete production in two stages. The first stage comprised of normal aggregate concrete (NAC produced with normal aggregates and 100% ordinary Portland cement (OPC. Meanwhile, the second stage involved production of concrete comprising of cupola furnace slag an aggregates with 100% ordinary Portland cement (OPC and subsequently with 2%, 4%, 6%, 8% and 10% cementitious replacement with granulated cupola furnace slag that had been grounded and milled to less than 75 µm diameter. The outcomes of compressive strength test conducted on the slag aggregate concrete (SAC with and without granulated slag cementitious replacement were satisfactory compared to normal aggregate concretes (NAC.

  4. Granular gas dynamics

    CERN Document Server

    Brilliantov, Nikolai

    2003-01-01

    While there is not yet any general theory for granular materials, significant progress has been achieved for dilute systems, also called granular gases. The contributions in this book address both the kinetic approach one using the Boltzmann equation for dissipative gases as well as the less established hydrodynamic description. The last part of the book is devoted to driven granular gases and their analogy with molecular fluids. Care has been taken so as to present the material in a pedagogical and self-contained way and this volume will thus be particularly useful to nonspecialists and newcomers to the field.

  5. Glass melting furnace

    International Nuclear Information System (INIS)

    The present invention concerns a glass melting furnace for processing radioactive liquid wastes discharged from nuclear facilities, and provides a furnace in which an accumulation layer of a glass material is not formed on the surface of a liquid glass. Namely, the melting furnace main body has a storing space capable of storing liquid glass. A starting material supply port is disposed to the upper portion of the melting furnace main body passing from the outside of the main body to the storing space, which can pass the glass material. A liquid waste supply port is disposed to the upper portion of the melting furnace main body passing from the outside of the main body to the storing space. Since the starting material supply port and the liquid waste supply port are disposed separately, each of the materials is supplied alone to a predetermined portion of the inside of the storing space. An accumulation layer of the glass material is not formed on the surface of the liquid glass. Accordingly, the liquefying progress of the glass material is not hindered. As a result, the operation efficiency of the plant can be improved. (I.S.)

  6. Radioactive waste melting furnace

    International Nuclear Information System (INIS)

    The present invention provides a radioactive waste melting furnace excellent in heat insulating property, capable of exchanging only refractory materials with lesser amount of contamination. Namely, an heat insulation layer is disposed on the outer wall of the melting furnace. A refractory layer is disposed on the inner wall being in contact with molten materials in the melting furnace. A metal vessel covering the refractory layer is interposed between the heat insulation layer and the refractory layer. In addition, a metal outer shell covering the heat insulation layer is disposed on the heat insulation layer on the outer wall of the melting furnace. Bricks comprising, for example, alumina, carbon, zircon, magnesia or chromia having a low heat conductivity are used for the outer wall heat insulation layer irrespective of the melting performance. The refractory layer on the inner wall is made of bricks comprising chromia, alumina and zircon as molten materials of low basicity and chromia and magnesia as molten materials of high basicity. The materials of the metal vessel may be ordinary carbon steels, cast irons, or stainless steels. The refractory layer is taken out from the melting furnace together with the metal vessel, and only the refractory layer can be removed. Radiation contamination is eliminated. The metal vessel can be used again. (I.S.)

  7. MICROSTRUCTURE OF GRANULAR BAINITE

    OpenAIRE

    Josefsson, B.; Andrén, H.-O.

    1988-01-01

    A 2.25Cr - 1Mo - 0.1C welded steel having a microstructure described as "granular bainite" has been investigated using optical microscopy, electron microscopy and atom probe field ion microscopy. Granular bainite was found to consist of bainitic ferrite and retained austenite, but no cementite. Grains of ferrite are built up by parallel platelike subgrains - bainitic ferrite. The carbon concentration changes abruptly at the ferrite - retained austenite interface but no diffusion of substituti...

  8. Metastasizing granular cell ameloblastoma

    OpenAIRE

    Bansal, Anju; Bhatnagar, Amar; Saxena, Sunita

    2012-01-01

    Ameloblastoma is a slow growing odontogenic epithelial tumor of jaw. It accounts for 1% of all tumors and cysts arising in maxilla and mandible. Although it is locally invasive and has a marked tendency to recur, metastasis is rare. Of the various histological patterns of ameloblastoma, the granular cell type is extremely rare accounting for 4% of ameloblastomas. We report a case of granular cell ameloblastoma with metastasis to the cervical lymph node presenting in a 40-year-old Indian female.

  9. Forced Granular Orifice Flow

    OpenAIRE

    Peng, Zheng; Zheng, Hepeng; Jiang, Yimin

    2009-01-01

    The flow of granular material through an orifice is studied experimentally as a function of force $F$ pushing the flow. It is found that the flow rate increases linearly with $F$ -- a new, unexpected result that is in contrast to the usual view that $F$, completely screened by an arch formed around the orifice, has no way of altering the rate. Employing energy balance, we show that this behavior results mainly from dissipation in the granular material.

  10. Blast Dynamics in a Dissipative Gas

    Science.gov (United States)

    Barbier, M.; Villamaina, D.; Trizac, E.

    2015-11-01

    The blast caused by an intense explosion has been extensively studied in conservative fluids, where the Taylor-von Neumann-Sedov hydrodynamic solution is a prototypical example of self-similarity driven by conservation laws. In dissipative media, however, energy conservation is violated, yet a distinctive self-similar solution appears. It hinges on the decoupling of random and coherent motion permitted by a broad class of dissipative mechanisms. This enforces a peculiar layered structure in the shock, for which we derive the full hydrodynamic solution, validated by a microscopic approach based on molecular dynamics simulations. We predict and evidence a succession of temporal regimes, as well as a long-time corrugation instability, also self-similar, which disrupts the blast boundary. These generic results may apply from astrophysical systems to granular gases, and invite further cross-fertilization between microscopic and hydrodynamic approaches of shock waves.

  11. Scaling of granular temperature in a vibrated granular bed.

    Science.gov (United States)

    Zivkovic, V; Biggs, M J; Glass, D H

    2011-03-01

    Granular temperature underpins the kinetic theory of granular flows as well as models for heat transfer, segregation, erosion, attrition, and aggregation in various granular systems. It is generally thought that granular temperature in vibrated granular systems scales with the square of the peak vibrational velocity. However, careful diffusing wave spectroscopy experiments and statistical analysis of data obtained from these for a three-dimensional vibrated bed of monodisperse glass particles reveals that the granular temperature is also significantly correlated with other vibrational parameters. Reexamination of previously published data obtained by others using alternative methods further supports our thus far unremarked upon observation reported here. PMID:21517495

  12. Carbon rod furnace infrared source

    Science.gov (United States)

    Boyd, W. J.; Jennings, D. E.; Blass, W. E.; Gailar, N. M.

    1974-01-01

    A carbon rod furnace infrared source has been built and has proven to be a reliable and trouble-free source despite the high rod temperature of 2500 K. The furnace offers several advantages over previous furnaces. These include an increase in usable rod length to 6.35 cm, extended rod life, and a fully automated power supply for the furnace. Construction and operational details are discussed.

  13. Blast furnace refractory lining wear status using radioactive sources. I

    International Nuclear Information System (INIS)

    The use of radioactive sources provides a means of determining the performance of new lining designs and new refractories less than campaign time periods, thereby allowing material and/or design changes for improved service. In this two-part article, which is from a paper presented at the AIME 1974 Ironmaking Conference, Part I deals with the techniques of the method. A description is given of the use of radioactive 60Co in sizes ranging from 1.5 to 5.0 millicuries in the refractory lining. The 60Co sources are encapsulated with stainless steel cylinders, with their caps heliarc welded. The cylinders are small

  14. Hot metal temperature prediction by neural networks in blast furnace

    International Nuclear Information System (INIS)

    In this work, the process called ECAD (Equal Channel Angular Drawing) is studied. A material is passed through a die with a constant transverse section, which contains an angle, generally, between 90 degree centigree and 135 degree centigree. For this purpose, three aluminium alloys are processed: 1370, 6101 and the 6061 alloy by the routes A, B and C. The evolution of the microstructure is observed according to the number of passes (N) and the thermal treatment. Observations by optical and SEM microscopy show the refinement in the grain size of these alloys in relation to the starting alloy. In addition, a simulation of the process with 90 degree and 120 degree centigree angles by using Finite Elements Modelling (FEM) is performed. Low friction conditions (?=0,01) and high friction conditions (?0.4) are assumed in order to establish the friction conditions that lead to the highest deformation values and allow to obtain a high homogeneity. The results obtained with the 1370 alloy show grain sizes of 7 (m after the first passage of ECAD performed by the Route C. Hence, the processing of alloys by the ECAD process would have industrial applicability if a final passage through a calibrated die is performed in order to obtain a constant cross section of the processed alloys. (Author) 30 refs

  15. Environmental assessment of blast furnace slag aggregates production

    OpenAIRE

    NOUVION, S; Jullien, A.; BRUNCHER, P

    2005-01-01

    Cet article présente une étude environnementale relative à la production en carrière de laitier de haut fourneau utilisé comme granulat en technique routière. Plusieurs type de données ont été recueillis sur le site de la Société Lorraine d'Agrégats (SLAG) a Moyeuvre-Grande (54) pour réaliser un inventaire de cycle de vie des fractions granulaires produites. Après analyse, ces données ont permis la modélisation de la productioin de laitier. L'énergie consommée à la tonne de laitier fabriqué ...

  16. Modern BLAST Programs

    Science.gov (United States)

    Ma, Jian; Zhang, Louxin

    The Basic Local Alignment Search Tool (BLAST) is arguably the most widely used program in bioinformatics. By sacrificing sensitivity for speed, it makes sequence comparison practical on huge sequence databases currently available. The original version of BLAST was developed in 1990. Since then it has spawned a variant of specialized programs. This chapter surveys the development of BLAST and BLAST-like programs for homology search, discusses alignment statistics that are used in assessment of reported matches in BLAST, and provides the reader with guidance to select appropriate programs and set proper parameters to match research requirements.

  17. Shaken Granular Lasers

    CERN Document Server

    Folli, Viola; Leuzzi, Luca; Conti, Claudio

    2012-01-01

    Granular materials have been studied for decades, also driven by industrial and technological applications. These very simple systems, composed by agglomerations of mesoscopic particles, are characterized, in specific regimes, by a large number of metastable states and an extreme sensitivity (e.g., in sound transmission) on the arrangement of grains; they are not substantially affected by thermal phenomena, but can be controlled by mechanical solicitations. Laser emission from shaken granular matter is so far unexplored; here we provide experimental evidence that it can be affected and controlled by the status of motion of the granular, we also find that competitive random lasers can be observed. We hence demonstrate the potentialities of gravity affected moving disordered materials for optical applications, and open the road to a variety of novel interdisciplinary investigations, involving modern statistical mechanics and disordered photonics.

  18. Impact of granular drops

    KAUST Repository

    Marston, J. O.

    2013-07-15

    We investigate the spreading and splashing of granular drops during impact with a solid target. The granular drops are formed from roughly spherical balls of sand mixed with water, which is used as a binder to hold the ball together during free-fall. We measure the instantaneous spread diameter for different impact speeds and find that the normalized spread diameter d/D grows as (tV/D)1/2. The speeds of the grains ejected during the “splash” are measured and they rarely exceed twice that of the impact speed.

  19. Mysteries of Granular Planet

    OpenAIRE

    Mikhail N. Skachkov

    2013-01-01

    The behavior of self-organizing granular medium in its own gravitational field is considered. The study is led within an approach proposing the existence of only three types of mesoscopic states in the material: so named hydrostatic, columnar and arched mesoscopic states. The results of this study are not obvious. Indeed, in the center of granular gravitating ball, as it turns out, pressure may be absent, though it is well-known that the pressure in either non-compressible liquid or solid li...

  20. Granular Convection in Microgravity

    CERN Document Server

    Murdoch, N; Nordstrom, K; Green, S F; Michel, P; de Lophem, T -L; Losert, W

    2013-01-01

    We investigate the role of gravity on convection in a dense granular shear flow. Using a microgravity modified Taylor-Couette shear cell under the conditions of parabolic flight microgravity, we demonstrate experimentally that secondary, convective-like flows in a sheared granular material are close to zero in microgravity and enhanced under high-gravity conditions, though the primary flow fields are unaffected by gravity. We suggest that gravity tunes the frictional particle-particle and particle-wall interactions, which have been proposed to drive the secondary flow. In addition, the degree of plastic deformation increases with increasing gravitational forces, supporting the notion that friction is the ultimate cause.

  1. Análise fluido-dinâmica do escoamento em ensaio de permeabilidade ao ar de argamassas preparadas com cimento Portland de alto-forno Fluid-dynamic analysis of the flow in air permeability measurement of mortars prepared with blast-slag furnace Portland cement

    Directory of Open Access Journals (Sweden)

    V. M. Pereira

    2008-06-01

    Full Text Available O estudo dos fenômenos fluido-dinâmicos de escoamento em meios porosos tem sido de grande interesse por diversas áreas das ciências, de forma a se avaliar não só a permeabilidade do material, mas também analisar o comportamento do fluido permeante quando no interior destes materiais. Tratando-se de compósitos à base de cimento, a mensuração da permeabilidade torna-se fundamental para que sua durabilidade possa ser estimada, pois é a permeabilidade que controla a taxa de ingresso e movimentação de agentes deletérios no interior destes materiais. Dessa forma, diversas metodologias e equacionamentos matemáticos têm sido utilizados para prever a permeabilidade de materiais à base de cimento. No entanto, várias discrepâncias e disparidades nos resultados têm sido encontradas. Dentre as metodologias empregadas para mensurar a permeabilidade de meios porosos, encontra-se a desenvolvida por Thenoz, a qual tem demonstrado bons resultados em materiais à base de cimento. Dessa forma, este trabalho visa, por meio de ensaio de permeabilidade ao ar, realizado de acordo com a metodologia de Thenoz, avaliar o comportamento fluido-dinâmico do ar durante o ensaio de permeabilidade em argamassas. Para isto, foram utilizadas argamassas preparadas com dois tipos de cimento Portland (CP II E - 32 e CP III - 32, duas relações água/cimento (0,5 e 0,6 e ensaiadas em idades de 14 e 28 dias. Por meio dos resultados obtidos foi possível observar que durante o escoamento a compressibilidade do ar pode ser ignorada e o regime de escoamento pode ser considerado como laminar, demonstrando que a metodologia proposta por Thenoz e o equacionamento matemático empregado pode resultar em coeficientes de permeabilidade ao ar confiáveis, pois fenômenos e considerações que poderiam influenciar neste tipo de escoamento podem ser negligenciados.Fluid-dynamic phenomena study in porous media flow has been of great interest for diverse areas of sciences. These studies not only have evaluated the permeability of porous media, but also to analyze the behavior of the fluid during the flow. Being about to the cement based materials, the measuring of the permeability becomes basic so that the durability of these can be estimate, therefore is the permeability that controls the rate of ingression and movement of deleterious agents inside these materials. Thus, diverse methodologies and mathematical equations have been used to foresee the permeability of cementitious materials, however, some discrepancies and nonsense in the results have been found. Amongst the used methodologies to measure the permeability of porous media, one meets developed it by Thenoz, which it has demonstrated good results in cement based materials. Thus, this work aims at, by means of assay of permeability to air, carried through in accordance with the methodology of Thenoz, to evaluate the fluid-dynamic behavior of air during the assay of permeability in mortars. For this, mortars prepared with two types of Portland cement of blast furnace (CP IIE-32 and CP III - 32, two relations water/cement (0.5 and 0.6 and ages of 14 and 28 days were used. By means of the gotten results it was possible to observe that during the draining the compressibility of air can be ignored, the regimen of draining can be considered as to plate, demonstrating that the methodology proposal for Thenoz and used mathematical equations can result in coefficients of trustworthy air permeability, therefore phenomena and considerations that could influence in this type of flow can be neglected, in accordance with what it is considered by literature.

  2. Análise fluido-dinâmica do escoamento em ensaio de permeabilidade ao ar de argamassas preparadas com cimento Portland de alto-forno / Fluid-dynamic analysis of the flow in air permeability measurement of mortars prepared with blast-slag furnace Portland cement

    Scientific Electronic Library Online (English)

    V. M., Pereira; E., Carvalho; P. S., Bardella; G., Camarini.

    2008-06-01

    Full Text Available O estudo dos fenômenos fluido-dinâmicos de escoamento em meios porosos tem sido de grande interesse por diversas áreas das ciências, de forma a se avaliar não só a permeabilidade do material, mas também analisar o comportamento do fluido permeante quando no interior destes materiais. Tratando-se de [...] compósitos à base de cimento, a mensuração da permeabilidade torna-se fundamental para que sua durabilidade possa ser estimada, pois é a permeabilidade que controla a taxa de ingresso e movimentação de agentes deletérios no interior destes materiais. Dessa forma, diversas metodologias e equacionamentos matemáticos têm sido utilizados para prever a permeabilidade de materiais à base de cimento. No entanto, várias discrepâncias e disparidades nos resultados têm sido encontradas. Dentre as metodologias empregadas para mensurar a permeabilidade de meios porosos, encontra-se a desenvolvida por Thenoz, a qual tem demonstrado bons resultados em materiais à base de cimento. Dessa forma, este trabalho visa, por meio de ensaio de permeabilidade ao ar, realizado de acordo com a metodologia de Thenoz, avaliar o comportamento fluido-dinâmico do ar durante o ensaio de permeabilidade em argamassas. Para isto, foram utilizadas argamassas preparadas com dois tipos de cimento Portland (CP II E - 32 e CP III - 32), duas relações água/cimento (0,5 e 0,6) e ensaiadas em idades de 14 e 28 dias. Por meio dos resultados obtidos foi possível observar que durante o escoamento a compressibilidade do ar pode ser ignorada e o regime de escoamento pode ser considerado como laminar, demonstrando que a metodologia proposta por Thenoz e o equacionamento matemático empregado pode resultar em coeficientes de permeabilidade ao ar confiáveis, pois fenômenos e considerações que poderiam influenciar neste tipo de escoamento podem ser negligenciados. Abstract in english Fluid-dynamic phenomena study in porous media flow has been of great interest for diverse areas of sciences. These studies not only have evaluated the permeability of porous media, but also to analyze the behavior of the fluid during the flow. Being about to the cement based materials, the measuring [...] of the permeability becomes basic so that the durability of these can be estimate, therefore is the permeability that controls the rate of ingression and movement of deleterious agents inside these materials. Thus, diverse methodologies and mathematical equations have been used to foresee the permeability of cementitious materials, however, some discrepancies and nonsense in the results have been found. Amongst the used methodologies to measure the permeability of porous media, one meets developed it by Thenoz, which it has demonstrated good results in cement based materials. Thus, this work aims at, by means of assay of permeability to air, carried through in accordance with the methodology of Thenoz, to evaluate the fluid-dynamic behavior of air during the assay of permeability in mortars. For this, mortars prepared with two types of Portland cement of blast furnace (CP IIE-32 and CP III - 32), two relations water/cement (0.5 and 0.6) and ages of 14 and 28 days were used. By means of the gotten results it was possible to observe that during the draining the compressibility of air can be ignored, the regimen of draining can be considered as to plate, demonstrating that the methodology proposal for Thenoz and used mathematical equations can result in coefficients of trustworthy air permeability, therefore phenomena and considerations that could influence in this type of flow can be neglected, in accordance with what it is considered by literature.

  3. SIMULATION ANALYSIS OF PREHEATER CHARGE TO THE ROTARY FURNACE

    Directory of Open Access Journals (Sweden)

    Jan Mikula

    2015-08-01

    Full Text Available Mathematical modeling of heat aggregates is one of the fundamental methods of the mathematical modelling research. A mathematical model based on the method of elementary balances was created for the thermal treatment of granular and lumpy materials. The adaptation of the selected aggregate model is based on prior knowledge and experiments. The paper presents an adaptation of the mathematical model for the magnesite processing rotary furnace using the mode of caustic and clinker production. A simulation of the charge preheater impact based on the thin layer principle is implemented into the model. The main advantages of using this type of preheater of rotary furnace are smaller dimensions for a large exchange surface and low pressure losses.

  4. Smelting Furnaces between XVI and XVIII century in New Spain

    Directory of Open Access Journals (Sweden)

    Andrea Monroy Braham

    2015-01-01

    Full Text Available The Sixteenth century brought new techniques of mining extraction and transformation that substitute the ancient form of mining, handle by prehispanic cultures -like surface mining and small blast furnaces- to the New World. Although in all cases they were replaced, the old methods served to face the new conditions resulting in new extractive and transformation metallurgist constructions and new methods for drifting mining on barely develop mineral deposits in Nueva España. The study of the particularities and typology in the new constructions, allow us to know the ability to change, and the operations of this constructions in the mines that still survive.

  5. Simulation of Induction Furnace and Comparison with Actual Induction Furnace

    OpenAIRE

    Viralkumar J Solanki; Dr S.R Joshi; Prof J.K Chavda; Prof K.L Mokariya

    2013-01-01

    In this paper, at first, a matlab simulation ofinduction furnace model optimized resonant capacitor isdesigned for a practical induction furnace with parallel resonantinverter. Then rectifier and inverter snubber circuit are designedand voltage, current, THD and power were measured. Thismeasured value is compared with actual working industryfurnace data and conclusion is made that when furnace is notoperate at full load that time its power factor is very low andTHD is high.

  6. Simulation of Induction Furnace and Comparison with Actual Induction Furnace

    Directory of Open Access Journals (Sweden)

    Viralkumar J Solanki

    2013-09-01

    Full Text Available In this paper, at first, a matlab simulation ofinduction furnace model optimized resonant capacitor isdesigned for a practical induction furnace with parallel resonantinverter. Then rectifier and inverter snubber circuit are designedand voltage, current, THD and power were measured. Thismeasured value is compared with actual working industryfurnace data and conclusion is made that when furnace is notoperate at full load that time its power factor is very low andTHD is high.

  7. Dry ice blasting

    Science.gov (United States)

    Lonergan, Jeffrey M.

    1992-04-01

    As legal and societal pressures against the use of hazardous waste generating materials has increased, so has the motivation to find safe, effective, and permanent replacements. Dry ice blasting is a technology which uses CO2 pellets as a blasting medium. The use of CO2 for cleaning and stripping operations offers potential for significant environmental, safety, and productivity improvements over grit blasting, plastic media blasting, and chemical solvent cleaning. Because CO2 pellets break up and sublime upon impact, there is no expended media to dispose of. Unlike grit or plastic media blasting which produce large quantities of expended media, the only waste produced by CO2 blasting is the material removed. The quantity of hazardous waste produced, and thus the cost of hazardous waste disposal is significantly reduced.

  8. New gunpowder blasting

    International Nuclear Information System (INIS)

    This book introduces gunpowder blasting, which consists of ten chapters. It deals with conception of gunpowder on the history of gunpowder, difference between gunpowder and general materials and classification of gunpowder, reaction of gunpowder, shock wave and detonation, on properties, material velocity and structure, test method on gunpowder and an article processed with heat, gunpowder such as igniter charge, carlit and slurry gunpowder, propellant and an article processed with heat, blasting on basics and Bench cut, blasting operations and security blasting construction and using of gunpowder.

  9. Carbon-free induction furnace

    Science.gov (United States)

    Holcombe, Cressie E. (Knoxville, TN); Masters, David R. (Knoxville, TN); Pfeiler, William A. (Norris, TN)

    1985-01-01

    An induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of carbon free materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloy. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an RF induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650.degree. C. for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

  10. Sintering furnace with hydrogen carbon dioxide atmosphere

    International Nuclear Information System (INIS)

    A heated furnace for sintering structures of uranium oxide containing composition being introduced to the furnace is described. The furnace receives an atmosphere comprising a mixture of hydrogen and carbon dioxide as initially introduced to the furnace, and this mixture reacts in the furnace to give the presence of water vapor and carbon monoxide

  11. Stresses in Granular Materials

    Science.gov (United States)

    Behringer, R.; Geng, J.; Longhi, E.; Howell, D.; Clement, E.; Reydellet, G.

    2000-11-01

    Forces are carried in a granular materials along tenuous complex structures--force/stress chains, whose properties depend on the sample preparation. Several models of force propagation have been proposed recently, a) the q-model of Coppersmith et al. and b) the three-leg model of Claudin et al. The first predicts a parabolic PDE for stresses in the continuum limit, and the second predicts a hyperbolic PDE. We present two experiments that probe force propagation in granular materials. Both use 2D particles (disks and pentagons) made from a photoelastic material. The first experiment determines the response function by applying local forces. We explore both ordered packings of disks and disordered packings of pentagons. For the disks, the response follows a `cone' that broadens with distance from the source. For the pentagons, this structure is present but less clear. The second set of experiments explores the effects of preparation on the stresses at the bottom of a 2D granular heap. We determine the force on a horizontal band of disks near the bottom of the heap. There is a clear force minimum if the disks are poured from a fixed-height funnel, but for other preparation techniques, the presence of a stress dip is more subtle. The most dramatic difference related to preparation occurs in the orientation of the grain contacts.

  12. Cupola Furnace Computer Process Model

    Energy Technology Data Exchange (ETDEWEB)

    Seymour Katz

    2004-12-31

    The cupola furnace generates more than 50% of the liquid iron used to produce the 9+ million tons of castings annually. The cupola converts iron and steel into cast iron. The main advantages of the cupola furnace are lower energy costs than those of competing furnaces (electric) and the ability to melt less expensive metallic scrap than the competing furnaces. However the chemical and physical processes that take place in the cupola furnace are highly complex making it difficult to operate the furnace in optimal fashion. The results are low energy efficiency and poor recovery of important and expensive alloy elements due to oxidation. Between 1990 and 2004 under the auspices of the Department of Energy, the American Foundry Society and General Motors Corp. a computer simulation of the cupola furnace was developed that accurately describes the complex behavior of the furnace. When provided with the furnace input conditions the model provides accurate values of the output conditions in a matter of seconds. It also provides key diagnostics. Using clues from the diagnostics a trained specialist can infer changes in the operation that will move the system toward higher efficiency. Repeating the process in an iterative fashion leads to near optimum operating conditions with just a few iterations. More advanced uses of the program have been examined. The program is currently being combined with an ''Expert System'' to permit optimization in real time. The program has been combined with ''neural network'' programs to affect very easy scanning of a wide range of furnace operation. Rudimentary efforts were successfully made to operate the furnace using a computer. References to these more advanced systems will be found in the ''Cupola Handbook''. Chapter 27, American Foundry Society, Des Plaines, IL (1999).

  13. Fiscal 1998 research report. Replacement of the open furnace with the electric furnace at Kuznetsk Steel Works, Russia; 1998 nendo chosa hokokusho. Russia Kuznetsk seitetsusho tenroka

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    For preventing global warming due to greenhouse effect gases, basic research was made on energy saving measures by replacement of the open furnace with the electric furnace at Kuznetsk Steel Works in Kemerovo State of Russia. KMK proposed 'replacement of the open furnace with the electric furnace' for reducing greenhouse effect gas emissions at Kuznetsk Steel Works from the following reasons. KMK's market share has been decreasing since dissolution of USSR, and KMK forecasts its future market share to be a maximum of 2 million tons/y. Consequently, it is difficult for KMK to adopt this replacement project which leads to over- production capacity, from the viewpoint of payability and fund raising. Since the main production process by electric furnace uses scrap as main material, the considerable improvement of the whole steel works including coke, sintering and blast furnace plants is possible. The replacement thus results in improvement of an international competitive power, solution of environmental pollution problems, and reduction of greenhouse effect gas emissions. KMK hopes to put this project into practice strongly. (NEDO)

  14. Granular cell ameloblastoma mimicking oncocytoma

    OpenAIRE

    Oza, Nirima; Agrawal, Karoon

    2012-01-01

    Granular cell ameloblastoma is a variant of ameloblastoma where cells located in the central portion of the follicles have granular eosinophilic cytoplasm and the peripheral cells resemble ameloblasts. A case of granular cell ameloblastoma of the mandible having very similar histopathological features of oncocytoma (oxyphilic adenoma) is reported where tumor cells were arranged in cords, sheets and follicles and their cytoplasm was full of eosinophilic granules.

  15. Granular cell ameloblastoma mimicking oncocytoma

    Directory of Open Access Journals (Sweden)

    Nirima Oza

    2012-01-01

    Full Text Available Granular cell ameloblastoma is a variant of ameloblastoma where cells located in the central portion of the follicles have granular eosinophilic cytoplasm and the peripheral cells resemble ameloblasts. A case of granular cell ameloblastoma of the mandible having very similar histopathological features of oncocytoma (oxyphilic adenoma is reported where tumor cells were arranged in cords, sheets and follicles and their cytoplasm was full of eosinophilic granules.

  16. Advanced Granular System Modeling Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Spaceports of the future will utilize new granular materials in unique applications including insulation for cryogenic tanks and Lunar regolith processing for...

  17. Mathematical models of granular matter

    CERN Document Server

    Mariano, Paolo; Giovine, Pasquale

    2008-01-01

    Granular matter displays a variety of peculiarities that distinguish it from other appearances studied in condensed matter physics and renders its overall mathematical modelling somewhat arduous. Prominent directions in the modelling granular flows are analyzed from various points of view. Foundational issues, numerical schemes and experimental results are discussed. The volume furnishes a rather complete overview of the current research trends in the mechanics of granular matter. Various chapters introduce the reader to different points of view and related techniques. New models describing granular bodies as complex bodies are presented. Results on the analysis of the inelastic Boltzmann equations are collected in different chapters. Gallavotti-Cohen symmetry is also discussed.

  18. Vertical boiler furnace

    Energy Technology Data Exchange (ETDEWEB)

    Serant, F.A.; Bulgakov, V.V.; Parshin, A.A.; Pugach, L.I.; Tochilkin, V.N.

    1982-01-01

    It is proposed that in the annular furnace (F) of an energy boiler formed of coaxially arranged internal and outer tubular screen having the shape of a regular polyhedron, that two-light screens be installed radially in the cavity of the F, adjoining with the internal and outer edge of the angles of the corresponding side screens. The number of two-light screens can be equal to or less than the number of edges of the F. The burners are installed on each outer edge of the F and are directed radially. Motion of gases in the F is vertically upwards. As compared to the annular F according to cert. of author. of the USSR number658358, the heat absorbing surface of the F has been significantly enlarged, which made it possible to reduce its overall dimensions, and consequently, the capital outlays for its construction.

  19. BLAST+: architecture and applications

    Directory of Open Access Journals (Sweden)

    Bealer Kevin

    2009-12-01

    Full Text Available Abstract Background Sequence similarity searching is a very important bioinformatics task. While Basic Local Alignment Search Tool (BLAST outperforms exact methods through its use of heuristics, the speed of the current BLAST software is suboptimal for very long queries or database sequences. There are also some shortcomings in the user-interface of the current command-line applications. Results We describe features and improvements of rewritten BLAST software and introduce new command-line applications. Long query sequences are broken into chunks for processing, in some cases leading to dramatically shorter run times. For long database sequences, it is possible to retrieve only the relevant parts of the sequence, reducing CPU time and memory usage for searches of short queries against databases of contigs or chromosomes. The program can now retrieve masking information for database sequences from the BLAST databases. A new modular software library can now access subject sequence data from arbitrary data sources. We introduce several new features, including strategy files that allow a user to save and reuse their favorite set of options. The strategy files can be uploaded to and downloaded from the NCBI BLAST web site. Conclusion The new BLAST command-line applications, compared to the current BLAST tools, demonstrate substantial speed improvements for long queries as well as chromosome length database sequences. We have also improved the user interface of the command-line applications.

  20. Passive blast pressure sensor

    Science.gov (United States)

    King, Michael J.; Sanchez, Roberto J.; Moss, William C.

    2013-03-19

    A passive blast pressure sensor for detecting blast overpressures of at least a predetermined minimum threshold pressure. The blast pressure sensor includes a piston-cylinder arrangement with one end of the piston having a detection surface exposed to a blast event monitored medium through one end of the cylinder and the other end of the piston having a striker surface positioned to impact a contact stress sensitive film that is positioned against a strike surface of a rigid body, such as a backing plate. The contact stress sensitive film is of a type which changes color in response to at least a predetermined minimum contact stress which is defined as a product of the predetermined minimum threshold pressure and an amplification factor of the piston. In this manner, a color change in the film arising from impact of the piston accelerated by a blast event provides visual indication that a blast overpressure encountered from the blast event was not less than the predetermined minimum threshold pressure.

  1. Granular mechanics and rifting

    Science.gov (United States)

    Reber, Jacqueline E.; Hayman, Nicholas W.; Lavier, Luc L.

    2013-04-01

    Numerical models have proved useful in the interpretation of seismic-scale images of rifted margins. In an effort to both test and further illuminate predictions of numerical models, workers have made some strides using map-scale field relations, microstructures, and strain analyses. Yet, fundamental predictions of modeling and tectonic restorations are not able to capture critical observations. For example, many models and interpretations call on continuous faults with restorable kinematic histories. In contrast, s-reflectors and other interpreted shear fabrics in the middle crust tend to be discontinuous and non-planar across a margin. Additionally, most rift-evolution models and interpretations call on end-member ductile flow laws over a range of mechanical and thermal conditions. In contrast, field observations have found that a range of "brittle" fault rocks (e.g., cataclasites and breccias) form in the deeper crust. Similarly, upper crustal materials in deep basins and fault zones can deform through both distributed and localized deformation. Altogether, there appears to be reason to bring a new perspective to aspects of the structural evolution of rifted margins. A granular mechanics approach to crustal deformation studies has several important strengths. Granular materials efficiently localize shear and exhibit a range of stick-slip behaviors, including quasi-viscous rheological responses. These behaviors emerge in discrete element models, analog-materials experiments, and natural and engineered systems regardless of the specific micromechanical flow law. Yet, strictly speaking, granular deformation occurs via failure of frictional contacts between elastic grains. Here, we explore how to relate granular-mechanics models to mesoscale (outcrop) structural evolution, in turn providing insight into basin- and margin- scale evolution. At this stage we are focusing on analog-materials experiments and micro-to-mesoscale observations linking theoretical predictions to structural geological observations. With this combined approach we seek to establish characteristic length scales such as grain sizes and shear zone thicknesses, and time-scales such as stick-slip event dynamics. This would allow us to define a flow law at the mesoscale from comparing the experimental results and the field observations. This rheology could eventually be used to model the strain localization history of rifted margins

  2. Granular Avalanches in Fluids

    OpenAIRE

    Pont, S. Courrech du; Gondret, P.; Perrin, B.; Rabaud, M.

    2002-01-01

    Three regimes of granular avalanches in fluids are put in light depending on the Stokes number St which prescribes the relative importance of grain inertia and fluid viscous effects, and on the grain/fluid density ratio r. In gas (r >> 1 and St > 1, e.g., the dry case), the amplitude and time duration of avalanches do not depend on any fluid effect. In liquids (r ~ 1), for decreasing St, the amplitude decreases and the time duration increases, exploring an inertial regime an...

  3. Instabilities in Granular Flow

    CERN Document Server

    Hendy, S

    2000-01-01

    We consider the stability of a system of equations which are a singular perturbation of the incompressible rigid-plastic flow equations used to model granular flow. A linear stability analysis shows that solutions of these equations are unstable, in general, and that these instabilities may lead to ill-posedness. However, the analysis suggests that these equations are more regular, in a certain sense, than the unperturbed incompressible rigid-plastic flow equations. Numerical solutions are presented which illustrate the growth of instabilities and the development of shear-bands in the flows.

  4. Axillary granular parakeratosis.

    Science.gov (United States)

    Mehregan, D A; Vandersteen, P; Sikorski, L; Mehregan, D R

    1995-08-01

    We report two cases of axillary granular parakeratosis, which is a unique eruption involving the axilla that has distinctive histopathologic features. Both of our patients had slightly pruritic, hyperpigmented patches in the axilla. The biopsy specimens revealed severe compact parakeratosis with maintenance of the stratum granulosum and retention of keratohyalin granules throughout the stratum corneum, which was markedly thickened and measured between 90 to 185 microns. The exact etiology is not known, but this conditions is believed to represent a contact reaction to an antiperspirant or deodorant. PMID:7615889

  5. Bulldozing of granular material

    CERN Document Server

    Sauret, A; Caulfield, C P; McElwaine, J N

    2014-01-01

    We investigate the bulldozing motion of a granular sandpile driven forwards by a vertical plate. The problem is set up in the laboratory by emplacing the pile on a table rotating underneath a stationary plate; the continual circulation of the bulldozed material allows the dynamics to be explored over relatively long times, and the variation of the velocity with radius permits one to explore the dependence on bulldozing speed within a single experiment. We measure the time-dependent surface shape of the dune for a range of rotation rates, initial volumes and radial positions, for four granular materials, ranging from glass spheres to irregularly shaped sand. The evolution of the dune can be separated into two phases: a rapid initial adjustment to a state of quasi-steady avalanching perpendicular to the blade, followed by a much slower phase of lateral spreading and radial migration. The quasi-steady avalanching sets up a well-defined perpendicular profile with a nearly constant slope. This profile can be scale...

  6. [Axillary granular parakeratosis].

    Science.gov (United States)

    Rodríguez, Gerzaín

    2002-12-01

    Axillary granular parakeratosis is an alteration of keratin characterized by a thick parakeratotic horny layer with abundant intracellular keratohyalin granules. It was first described in 1991 and since then 32 cases have been reported from USA, Europe and Australia. Lesions may affect intertriginous areas other than the axilla. The disease has apparently not been previously described in Latin America. Three overweight Colombian women were diagnosed with axillary granular parakeratosis. They presented encrusted, hyperkeratotic, hyperpigmented and pruriginous papules and plaques which affected both axillae in two women and only one in the other. Lesions had persisted for two and four months in two patients and for one year in the third. Clinical diagnoses were benign familiar pemphigus and tinea nigra. Skin biopsies showed a thick parakeratotic basophilic horny layer. Electron microscopy demonstrated a high content of keratohyalin granules. No Langerhans cells were demonstrated in the lesions using IHC for S-100 protein. No fungi were seen with the PAS stain. Infundibula showed thick horny plugs with changes similar to those seen in the epidermis. Dermal tissue showed few perivascular lymphocytes. These findings suggest that the disease has an irritative pathogenesis. Clinical histories indicated that the three women were overweight and used several types of antiperspirants. These factors plus local irritation and humidity apparently triggered the keratinization response. PMID:12596449

  7. Computer cast blast modelling

    Energy Technology Data Exchange (ETDEWEB)

    Chung, S. [ICI Explosives Canada, North York, ON (Canada); McGill, M. [ICI Explosives USA, Dallas, TX (United States); Preece, D.S. [Sandia National Labs., Albuquerque, NM (United States)

    1994-07-01

    Cast blasting can be designed to utilize explosive energy effectively and economically for coal mining operations to remove overburden material. The more overburden removed by explosives, the less blasted material there is left to be transported with mechanical equipment, such as draglines and trucks. In order to optimize the percentage of rock that is cast, a higher powder factor than normal is required plus an initiation technique designed to produce a much greater degree of horizontal muck movement. This paper compares two blast models known as DMC (Distinct Motion Code) and SABREX (Scientific Approach to Breaking Rock with Explosives). DMC, applies discrete spherical elements interacted with the flow of explosive gases and the explicit time integration to track particle motion resulting from a blast. The input to this model includes multi-layer rock properties, and both loading geometry and explosives equation-of-state parameters. It enables the user to have a wide range of control over drill pattern and explosive loading design parameters. SABREX assumes that heave process is controlled by the explosive gases which determines the velocity and time of initial movement of blocks within the burden, and then tracks the motion of the blocks until they come to a rest. In order to reduce computing time, the in-flight collisions of blocks are not considered and the motion of the first row is made to limit the motion of subsequent rows. Although modelling a blast is a complex task, the DMC can perform a blast simulation in 0.5 hours on the SUN SPARCstation 10--41 while the new SABREX 3.5 produces results of a cast blast in ten seconds on a 486-PC computer. Predicted percentage of cast and face velocities from both computer codes compare well with the measured results from a full scale cast blast.

  8. Fossil fuel furnace reactor

    Science.gov (United States)

    Parkinson, William J. (Los Alamos, NM)

    1987-01-01

    A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

  9. Valorization of electric arc furnace primary steelmaking slags for cement applications.

    Science.gov (United States)

    Kim, Hyung-Seok; Kim, Kee-Seok; Jung, Sung Suk; Hwang, Jin Ill; Choi, Jae-Seok; Sohn, Il

    2015-07-01

    To produce supplementary cementitious materials from electric arc furnace (EAF) slags, FeO was reduced using a two-stage reduction process that included an Al-dross reduction reaction followed by direct carbon reduction. A decrease in FeO was observed on tapping after the first-stage reduction, and further reduction with a stirred carbon rod in the second-stage reduction resulted in final FeO content below 5wt%, which is compatible with cement clinker applications. The reduced electric arc furnace slags (REAFS) mixed with cement at a unit ratio exhibited physical properties comparable to those of commercialized ground granulated blast furnace slags (GGBFS). Confocal laser scanning microscopy (CLSM) was used to obtain fundamental information on the cooling characteristics and conditions required to obtain amorphous REAFS. REAFS can be applied in cement mixtures to achieve the hydraulic properties needed for commercial use. PMID:25863765

  10. Locally Resonant Granular Chain

    CERN Document Server

    Bonanomi, Luca; Daraio, Chiara

    2014-01-01

    We report the design and testing of a tunable and nonlinear mechanical metamaterial, called locally resonant granular chain. It consists of a one-dimensional array of hollow spherical particles in contact, containing local resonators. The resonant particles are made of an aluminium outer spherical shell and a steel inner mass connected by a polymeric plastic structure acting as a spring. We characterize the linear spectra of the individual particles and of one-dimensional arrays of particles using theory, numerical analysis, and experiments. A wide band gap is observed as well as tunability of the dispersive spectrum by changing the applied static load. Finally, we experimentally explore the nonlinear dynamics of the resonant particles. By using nonlinear acoustical techniques, we reveal a complex, nonclassical nonlinear dynamics.

  11. Granularity-Adaptive Proof Presentation

    CERN Document Server

    Schiller, Marvin

    2009-01-01

    When mathematicians present proofs they usually adapt their explanations to their didactic goals and to the (assumed) knowledge of their addressees. Modern automated theorem provers, in contrast, present proofs usually at a fixed level of detail (also called granularity). Often these presentations are neither intended nor suitable for human use. A challenge therefore is to develop user- and goal-adaptive proof presentation techniques that obey common mathematical practice. We present a flexible and adaptive approach to proof presentation that exploits machine learning techniques to extract a model of the specific granularity of proof examples and employs this model for the automated generation of further proofs at an adapted level of granularity.

  12. Graphite furnace analysis

    International Nuclear Information System (INIS)

    The impact of microwave digestion, hot injection of solutions and chemical modification on the analysis of biological samples by electro-thermal atomic absorption spectrometry (AAS) has been assessed. The stabilizing effects of palladium and ruthenium modifiers were compared. Although ruthenium has a higher atom appearance temperature, palladium was a more useful modifier when samples other than water were analysed. When 2 ?g of palladium (as PdCl2) was preconditioned in hydrogen at 500 degC, volatile elements were retained at char temperatures up to 1000-1100 degC. This allowed similar atomizer programmes to be used for Cd, Cu, Fe, Mn and Pb and accurate determination of the analytes in solutions of reference materials was achieved against aqueous standards Rapid drying of the solutions by hot injection at 120 degC reduced programme time to just over 1 min. A combination of microwave digestion ,hot injection of 40% (w/v) HNO3 solutions and Pd modification produced a rapid and sensitive method for determination of Cd and Pb at sub-?g g-1 levels in vegetable and protein foodstuffs. Palladium modification also proved useful in simultaneous multielement determination by continuum source AAS. The picogram detection limits obtained for Cr, Mn and Pb were similar to line source AAS values recorded with the same compromise programme. Accurate determination of Cd, Cr, Cu, Mn, Mo and Pb in NIST SRM 1566 Oyster Tissue indicated the potential of continuum source AAS for multielement determinations. The advantages of palladium modifications were also illustrated for furnace atomic non-thermal excitation spectrometry (FANES) with hollow-cathode discharge. Maximum char temperatures of Ag, Ga, Hg, Pb, Sb and Se were increased by 300-600degC in the presence of 1 ?g of Pd, although detection limits were a factor of 2 poorer. (author). 58 refs.; 2 figs.; 17 tabs

  13. Modelamento da utilização de aglomerado autorredutor em minialto-forno com recirculação de gás de topo Modeling of self-reducing agglomerates charging in the mini blast furnace with top gas recycling

    OpenAIRE

    Ulysses Forastieri de Matos; José Adilson de Castro

    2012-01-01

    Os minialtos-fornos são reatores que, tradicionalmente, produzem gusa a partir de carvão vegetal, utilizando minério granular com alguma substituição de minério por carga elaborada. Nesse trabalho, propõe-se a substituição de carga metálica por aglomerado autoredutor com reaproveitamento de gás de topo reformado em minialtos-fornos com cenários onde o agente redutor seria o CV e retorno de coque de grandes altos fornos (small coque). Essa tecnologia foi avaliada, utilizando-se um código compu...

  14. Magnetoresistance of mesoscopic granular ferromagnets

    OpenAIRE

    Vilchik, A. Y. Dokow H.; Frydman, A.

    2005-01-01

    We have performed magnetoresistance (MR) measurements of granular ferromagnets having lateral dimensions smaller than 0.5 $\\mu$m and containing a small number of grains (down to about 100). Compared to macroscopic samples, these granular samples exhibit unusually large saturation fields and MR amplitudes. In addition, the evolution of the magnetoresistance curve as the intergrain distance decreases is qualitatively different than that of large samples. We discuss these resul...

  15. Lyapunov spectrum of granular gases.

    Science.gov (United States)

    McNamara, S; Mareschal, M

    2001-06-01

    We calculate and study the Lyapunov spectrum of a granular gas maintained in a steady state by an isokinetic thermostat. Considering restitution coefficients greater than unity allows us to show that the spectra change smoothly and continuously at equilibrium. The shearing instability of the granular gas, however, provokes an abrupt change in the structure of the spectrum. The relationship between various physically relevant quantities and the energy dissipation rate differs from previously studied nonequilibrium steady states. PMID:11415091

  16. Localizing energy in granular materials

    CERN Document Server

    Przedborski, Michelle A; Sen, Surajit

    2016-01-01

    A device for absorbing and storing short duration impulses in an initially uncompressed one-dimensional granular chain is presented. Simply stated, short regions of sufficiently soft grains are embedded in a hard granular chain. These grains exhibit long-lived standing waves of predictable frequencies regardless of the timing of the arrival of solitary waves from the larger matrix. We explore the origins, symmetry, and energy content of the soft region and its intrinsic modes.

  17. Memory Effects in Granular Material

    OpenAIRE

    Josserand, Christophe; Tkachenko, Alexei; Mueth, Daniel M.; Jaeger, Heinrich M.

    2000-01-01

    We present a combined experimental and theoretical study of memory effects in vibration-induced compaction of granular materials. In particular, the response of the system to an abrupt change in shaking intensity is measured. At short times after the perturbation a granular analog of aging in glasses is observed. Using a simple two-state model, we are able to explain this short-time response. We also discuss the possibility for the system to obey an approximate pseudo-fluctuation-dissipation ...

  18. Optimized Simulation of Granular Materials

    Science.gov (United States)

    Holladay, Seth

    Visual effects for film and animation often require simulated granular materials, such as sand, wheat, or dirt, to meet a director's needs. Simulating granular materials can be time consuming, in both computation and labor, as these particulate materials have complex behavior and an enormous amount of small-scale detail. Furthermore, a single cubic meter of granular material, where each grain is a cubic millimeter, would contain a billion granules, and simulating all such interacting granules would take an impractical amount of time for productions. This calls for a simplified model for granular materials that retains high surface detail and granular behavior yet requires significantly less computational time. Our proposed method simulates a minimal number of individual granules while retaining particulate detail on the surface by supporting surface particles with simplified interior granular models. We introduce a multi-state model where, depending on the material state of the interior granules, we replace interior granules with a simplified simulation model for the state they are in and automate the transitions between those states. The majority of simulation time can thus be focused on visible portions of the material, reducing the time spent on non-visible portions, while maintaining the appearance and behavior of the mass as a whole.

  19. Dynamics of Granular Stratification

    CERN Document Server

    Makse, H A; Stanley, H E; Warr, S; Makse, Hernan A.; Ball, Robin C.; Warr, Stephen

    1998-01-01

    Spontaneous stratification in granular mixtures has been recently reported by H. A. Makse et al. [Nature 386, 379 (1997)]. Here we study experimentally the dynamical processes leading to spontaneous stratification. Using a high-speed video camera, we study a rapid flow regime where the rolling grains size segregate during the avalanche. We characterize the dynamical process of stratification by measuring all relevant quantities: the velocity of the rolling grains, the velocity of the kink, the wavelength of the layers, the rate of collision between rolling and static grains, and all the angles of repose characterizing the mixture. The wavelength of the layers behaves linearly with the thickness of the layer of rolling grains (i.e., with the flow rate), in agreement with theoretical predictions. The velocity profile of the grains in the rolling phase is a linear function of the position of the grains along the moving layer. We also find that the speed of the upward-moving kink has the same value as the mean sp...

  20. Granular Superconductors and Gravity

    Science.gov (United States)

    Noever, David; Koczor, Ron

    1999-01-01

    As a Bose condensate, superconductors provide novel conditions for revisiting previously proposed couplings between electromagnetism and gravity. Strong variations in Cooper pair density, large conductivity and low magnetic permeability define superconductive and degenerate condensates without the traditional density limits imposed by the Fermi energy (approx. 10(exp -6) g cu cm). Recent experiments have reported anomalous weight loss for a test mass suspended above a rotating Type II, YBCO superconductor, with a relatively high percentage change (0.05-2.1%) independent of the test mass' chemical composition and diamagnetic properties. A variation of 5 parts per 104 was reported above a stationary (non-rotating) superconductor. In experiments using a sensitive gravimeter, bulk YBCO superconductors were stably levitated in a DC magnetic field and exposed without levitation to low-field strength AC magnetic fields. Changes in observed gravity signals were measured to be less than 2 parts in 108 of the normal gravitational acceleration. Given the high sensitivity of the test, future work will examine variants on the basic magnetic behavior of granular superconductors, with particular focus on quantifying their proposed importance to gravity.

  1. New furnace lining technology saves

    Energy Technology Data Exchange (ETDEWEB)

    Chari, S.R.

    2005-07-01

    Prices of coal and hydrocarbons are ever increasing to unaffordable levels due to ever growing demand, the threat of exhaustion of fossils, very slow rate of discovering new sources and price manipulation by the Organization of Petroleum Exporting Countries (OPEC). Hence energy conservation and minimization of energy loss are the crying needs and goal of the day; new generation furnace lining and insulation materials play a major role to achieve the goal. This paper discusses the new generation furnace lining technology and insulation materials for energy conservation. 4 figs., 2 tabs.

  2. Rock blasting effects and operations

    Energy Technology Data Exchange (ETDEWEB)

    Pijush Pal Roy [Central Mining Research Institute, Dhanbad (India)

    2005-07-01

    This book encapsulates theoretical and practical aspects of drilling and blasting techniques used in both surface and subterranean excavations connected with civil as well as mining activities. Case studies are presented to illustrate correlations between theoretical calculations and empirical findings. It also summarizes the results of research carried out by the Blasting Department of the Central Mining Research Institute since its inception in the year 1970. It contains fifteen extensive chapters covering statistical methods, design parameters, rock breakage mechanism, structural damage, fragmentation, emerging techniques, surface and sub-surface blasting methodologies, safety and environmental aspects, explosive characteristics and modern initiating devices. Selected contents: 1. Statistical Approaches and Useful Mathematical Formulae; 2. Terms and Parameters; 3. Detonation Principle and Rock Breakage Mechanism; 4. Strength of Explosives: Theoretical Derivation and Laboratory Determinations; 5. Prediction, Control and Damage Threshold of Ground Vibration from Opencast Blasting; 6. Structural Response and Damage Criteria for Safety of Surface Structures; 7. Influence of Blasting on Surface Structures and Underground Workings; 8. Blast Monitoring and Characterization; 9. Ringhole Blasting in Coal in Blasting Gallery Panels; 10. Rock Fragmentation and Assessment; 11. Socio-Economic and Environmental Impacts of Blasting; 12. Emerging Blasting Techniques; 13. Rock Excavation by Non-explosive Methods; 14. Blasting in Surface and Subsurface Hard Rocks; 15. Performance Evaluation of Explosives and Accessories.

  3. State-of-the-art electric steelmaking arc furnace in Japan through the year 2000

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, T.; Sugiyama, N.; Morikawa, T.; Miyashita, T.; Uesugi, H.; Hamamoto, S.; Ichihara, T.; Okazaki, K; Sobata, K.; Obama, M.; Iwasaki, Y.; Hashizume, A.; Takada, I. [Japanese Electroheat Association (Japan)

    1992-12-31

    A study was conducted in Japan to determine the progress of electric steelmaking arc furnaces toward the 21st century. The study covered demands for steel, working environment, new steel making methods and scrap used as a raw material. The aim of the new steelmaking process lies in the development of a manufacturing process that would satisfy the needs of higher levels of products which would harmonize with environmental problems. It was concluded that the anticipated share of crude steel production by electric steelmaking arc furnaces would reach the level of 35-40% in the early part of the 21st century. This would mean an effective use of resources since only scrap metal can be used in electric arc furnaces. Energy consumption would drop to 1/3 of that of blast furnace - converter process, and CO{sub 2} generation rate would also drop accordingly. Crude steel production with electric steelmaking arc furnaces will play an important role in the future. 4 refs., 5 tabs., 5 figs.

  4. High Efficiency Solar Furnace Core Project

    Data.gov (United States)

    National Aeronautics and Space Administration — It is proposed to develop a high efficiency solar furnace core that greatly lessens the heat losses from the furnace core, either greatly reducing the amount of...

  5. Dynamic granularity of imaging systems

    Science.gov (United States)

    Geissel, Matthias; Smith, Ian C.; Shores, Jonathon E.; Porter, John L.

    2015-11-01

    Imaging systems that include a specific source, imaging concept, geometry, and detector have unique properties such as signal-to-noise ratio, dynamic range, spatial resolution, distortions, and contrast. Some of these properties are inherently connected, particularly dynamic range and spatial resolution. It must be emphasized that spatial resolution is not a single number but must be seen in the context of dynamic range and consequently is better described by a function or distribution. We introduce the "dynamic granularity" G dyn as a standardized, objective relation between a detector's spatial resolution (granularity) and dynamic range for complex imaging systems in a given environment rather than the widely found characterization of detectors such as cameras or films by themselves. This relation can partly be explained through consideration of the signal's photon statistics, background noise, and detector sensitivity, but a comprehensive description including some unpredictable data such as dust, damages, or an unknown spectral distribution will ultimately have to be based on measurements. Measured dynamic granularities can be objectively used to assess the limits of an imaging system's performance including all contributing noise sources and to qualify the influence of alternative components within an imaging system. This article explains the construction criteria to formulate a dynamic granularity and compares measured dynamic granularities for different detectors used in the X-ray backlighting scheme employed at Sandia's Z-Backlighter facility.

  6. Training Guidelines: Glass Furnace Operators.

    Science.gov (United States)

    Ceramics, Glass, and Mineral Products Industry Training Board, Harrow (England).

    Technological development in the glass industry is constantly directed towards producing high quality glass at low operating costs. Particularly, changes have taken place in melting methods which mean that the modern furnace operator has greater responsibilities than any of his predecessors. The complexity of control systems, melting rates, tank…

  7. Model investigations 3D of gas-powder two phase flow in descending packed bed in metallurgical shaft furnaces

    OpenAIRE

    B. Panic; K. Janiszewski

    2014-01-01

    This paper presents the second phase of model investigations of static pressure radial distribution conducted on 4 levels of bed height. During the phase the diameter of glass bed particles was increased, blast-furnace pellets were introduced as bed and iron powder was used as powder. Experiments were carried out with regard to gas velocity, bed and powder type and size of bed particles. The radial distribution of 3 fractions of powder accumulated in the bed – static powder, dynamic powder an...

  8. Channel Formation in Granular Heaps

    Science.gov (United States)

    Lucy, Kwan; Nhat-Hang, Duong; Shinbrot, Troy

    2003-11-01

    While the exact mechanisms that govern granular flows remain poorly understood, detailed knowledge of the complex behavior of granular materials has become increasingly recognized to be important in understanding such phenomena as landslides, sand dunes, and ice floes as well as to be relevant to industrial processes which require the transport of small solid particles. In this study, we report newly discovered liquid-like channels that can form on the surface of granular heaps under conditions that reduce particle-settling speed relative to debris flow speed. In particular, we have determined that such channels indicating continuous flow patterns can be established using several types of dry grains. Furthermore, we have evaluated the effect of particle size, particle geometry, and flow rate on the development of channels.

  9. Simulations of granular gravitational collapse.

    Science.gov (United States)

    Kachuck, Samuel B; Voth, Greg A

    2013-12-01

    A freely cooling granular gas in a gravitational field undergoes a collapse to a multicontact state in a finite time. Previous theoretical [D. Volfson et al., Phys. Rev. E 73, 061305 (2006)] and experimental work [R. Son et al., Phys. Rev. E 78, 041302 (2008)] have obtained contradictory results about the rate of energy loss before the gravitational collapse. Here we use a molecular dynamics simulation in an attempt to recreate the experimental and theoretical results to resolve the discrepancy. We are able to nearly match the experimental results, and find that to reproduce the power law predicted in the theory we need a nearly elastic system with a constant coefficient of restitution greater than 0.993. For the more realistic velocity-dependent coefficient of restitution, there does not appear to be a power-law decay and the transition from granular gas to granular solid is smooth, making it difficult to define a time of collapse. PMID:24483431

  10. Hierarchical Structures in Granular Matter

    International Nuclear Information System (INIS)

    Granular matter, under the proper conditions of vibration, exhibits a behavior that closely resembles that of gases, liquids or solids. In a vibrated mix of glass particles and magnetic steel particles, it is also possible to observe aggregation phenomena, as well as, processes of reconstruction of the generated clusters. In this work we discuss the effects of the so called granular temperature on the evolution of the agglomerates generated by the magnetic interactions. On the basis of a fractal analysis and the measured mass distribution, we analyze experimental results on the static structural aspects of the aggregates originated by two methods we call: granular diffusion limited aggregation (GDLA) and growth limited by concentration (GLC)

  11. Mathematical modeling in mechanics of granular materials

    CERN Document Server

    Sadovskaya, Oxana

    2012-01-01

    This book covers numerical modeling of behavior of granular materials, building mixed-type models, describing the flow of granular materials in the presence of quasi-static deformation zones, with a numerical realization of models on multiprocessor computers.

  12. Teknologi Pembuatan Material Shot Blast untuk Mendukung Industri Pengecoran Logam Nasional

    Directory of Open Access Journals (Sweden)

    Fajar Nurjaman

    2009-01-01

    Full Text Available Shot blast material is a supporting material in foundry which is used at surface finishing process of metal casting. Recently, there is no one of national industry that produce shot blast material, in consequence, the purpose of this research is to lessen the dependence of using shot blast material import by making a shot blast material which improve its hardness exceed the shot blast material import. This research use the raw material from scrap iron with the following composition: C (3.2%, Si (1.18%, Mn (6.1%, Cu (0.35%, Fe (88.7%. The scrap is melted in induction furnace untill melt (hot metal, then the hot metal (1200 oC is tilted into a runner which is connected with pan crucible, which is consisted of 107 holes with diameter of each holes is 10 mm. Hot metal that is leave from the holes, is injected by pressurized water 1.1 atm with the velocity 0.8 m/s, untill obtained grains of shot blast material, then these grains goes into the water tank which it has temperature 40oC. From thermodynamic study, to avoid the happening of the explosion that is arising out because the effect of high temperature difference at injection process beetween water and hot metal, hence the comparison value beetween the mass of water and hot metal equal to 1:4.6. From this research is obtained shot blast material Ø0.8-3.2 mm with the metallography structure with martensite domination and dispersion of cementite and a little austenit. The hardness value of this material is 54.8 HRC, where this value is larger than shot blast material import (45-50 HRC. Abstract in Bahasa Indonesia: Material shot blast merupakan material pendukung pengecoran logam yang digunakan pada proses surface finishing benda cor logam. Saat ini belum ada satupun industri nasional yang memproduksi material shot blast, karena itu tujuan penelitian ini untuk mengurangi ketergantungan penggunaan material shot blast impor dengan membuat material shot blast yang nilai kekerasannya melebihi material shot blast impor. Penelitian ini menggunakan bahan baku scrap besi dengan komposisi: C (3,2%, Si (1,18%, Mn (6,1%, Cu (0,35% Fe (88,7%. Scrap dilebur dalam tungku induksi hingga mencair (hot metal, lalu hot metal (1200oC di tuang ke dalam runner yang terhubung dengan pan crucible yang terdiri dari 107 buah lubang berukuran Ø10 mm. Hot metal yang keluar dari lubang tersebut diinjeksi oleh air bertekanan 1,1 atm dengan kecepatan 0,8 m/s, hingga diperoleh butiran material shot blast, lalu butiran itu masuk ke dalam bak air bertemperatur 40oC. Dari kajian termodinamika, untuk menghindari terjadinya resiko ledakan yang timbul akibat diferensiasi temperatur yang tinggi saat proses injeksi, maka besarnya nilai perbandingan massa air dan hot metal sebesar 1:4,6. Dari penelitian ini diperoleh material shot blast berukuran Ø0,8-3.2 mm dengan struktur metalografi yang didominasi oleh struktur martensit dengan sebaran sementit dan sedikit austenit. Nilai kekerasan material ini adalah 54,8 HRC, dimana nilai ini melebihi nilai kekerasan material shot blast impor (45-50 HRC. Kata kunci: Shot blast, induction furnace, nozzle, hot metal, pengecoran logam.

  13. Initiation of immersed granular avalanches.

    Science.gov (United States)

    Mutabaruka, Patrick; Delenne, Jean-Yves; Soga, Kenichi; Radjai, Farhang

    2014-05-01

    By means of coupled molecular dynamics-computational fluid dynamics simulations, we analyze the initiation of avalanches in a granular bed of spherical particles immersed in a viscous fluid and inclined above its angle of repose. In quantitative agreement with experiments, we find that the bed is unstable for a packing fraction below 0.59 but is stabilized above this packing fraction by negative excess pore pressure induced by the effect of dilatancy. From detailed numerical data, we explore the time evolution of shear strain, packing fraction, excess pore pressures, and granular microstructure in this creeplike pressure redistribution regime, and we show that they scale excellently with a characteristic time extracted from a model based on the balance of granular stresses in the presence of a negative excess pressure and its interplay with dilatancy. The cumulative shear strain at failure is found to be ? 0.2, in close agreement with the experiments, irrespective of the initial packing fraction and inclination angle. Remarkably, the avalanche is triggered when dilatancy vanishes instantly as a result of fluctuations while the average dilatancy is still positive (expanding bed) with a packing fraction that declines with the initial packing fraction. Another nontrivial feature of this creeplike regime is that, in contrast to dry granular materials, the internal friction angle of the bed at failure is independent of dilatancy but depends on the inclination angle, leading therefore to a nonlinear dependence of the excess pore pressure on the inclination angle. We show that this behavior may be described in terms of the contact network anisotropy, which increases with a nearly constant connectivity and levels off at a value (critical state) that increases with the inclination angle. These features suggest that the behavior of immersed granular materials is controlled not only directly by hydrodynamic forces acting on the particles but also by the influence of the fluid on the granular microstructure. PMID:25353783

  14. HYPERELASTIC MODELS FOR GRANULAR MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Humrickhouse, Paul W; Corradini, Michael L

    2009-01-29

    A continuum framework for modeling of dust mobilization and transport, and the behavior of granular systems in general, has been reviewed, developed and evaluated for reactor design applications. The large quantities of micron-sized particles expected in the international fusion reactor design, ITER, will accumulate into piles and layers on surfaces, which are large relative to the individual particle size; thus, particle-particle, rather than particle-surface, interactions will determine the behavior of the material in bulk, and a continuum approach is necessary and justified in treating the phenomena of interest; e.g., particle resuspension and transport. The various constitutive relations that characterize these solid particle interactions in dense granular flows have been discussed previously, but prior to mobilization their behavior is not even fluid. Even in the absence of adhesive forces between particles, dust or sand piles can exist in static equilibrium under gravity and other forces, e.g., fluid shear. Their behavior is understood to be elastic, though not linear. The recent “granular elasticity” theory proposes a non-linear elastic model based on “Hertz contacts” between particles; the theory identifies the Coulomb yield condition as a requirement for thermodynamic stability, and has successfully reproduced experimental results for stress distributions in sand piles. The granular elasticity theory is developed and implemented in a stand- alone model and then implemented as part of a finite element model, ABAQUS, to determine the stress distributions in dust piles subjected to shear by a fluid flow. We identify yield with the onset of mobilization, and establish, for a given dust pile and flow geometry, the threshold pressure (force) conditions on the surface due to flow required to initiate it. While the granular elasticity theory applies strictly to cohesionless granular materials, attractive forces are clearly important in the interaction of micron-sized particles; extension of the theory to account for these effects is also considered. A set of continuum models are proposed for use in the future dust transport modeling.

  15. Initiation of immersed granular avalanches

    Science.gov (United States)

    Mutabaruka, Patrick; Delenne, Jean-Yves; Soga, Kenichi; Radjai, Farhang

    2014-05-01

    By means of coupled molecular dynamics-computational fluid dynamics simulations, we analyze the initiation of avalanches in a granular bed of spherical particles immersed in a viscous fluid and inclined above its angle of repose. In quantitative agreement with experiments, we find that the bed is unstable for a packing fraction below 0.59 but is stabilized above this packing fraction by negative excess pore pressure induced by the effect of dilatancy. From detailed numerical data, we explore the time evolution of shear strain, packing fraction, excess pore pressures, and granular microstructure in this creeplike pressure redistribution regime, and we show that they scale excellently with a characteristic time extracted from a model based on the balance of granular stresses in the presence of a negative excess pressure and its interplay with dilatancy. The cumulative shear strain at failure is found to be ?0.2, in close agreement with the experiments, irrespective of the initial packing fraction and inclination angle. Remarkably, the avalanche is triggered when dilatancy vanishes instantly as a result of fluctuations while the average dilatancy is still positive (expanding bed) with a packing fraction that declines with the initial packing fraction. Another nontrivial feature of this creeplike regime is that, in contrast to dry granular materials, the internal friction angle of the bed at failure is independent of dilatancy but depends on the inclination angle, leading therefore to a nonlinear dependence of the excess pore pressure on the inclination angle. We show that this behavior may be described in terms of the contact network anisotropy, which increases with a nearly constant connectivity and levels off at a value (critical state) that increases with the inclination angle. These features suggest that the behavior of immersed granular materials is controlled not only directly by hydrodynamic forces acting on the particles but also by the influence of the fluid on the granular microstructure.

  16. Traffic and Granular Flow '11

    CERN Document Server

    Buslaev, Alexander; Bugaev, Alexander; Yashina, Marina; Schadschneider, Andreas; Schreckenberg, Michael; TGF11

    2013-01-01

    This book continues the biannual series of conference proceedings, which has become a classical reference resource in traffic and granular research alike. It addresses new developments at the interface between physics, engineering and computational science. Complex systems, where many simple agents, be they vehicles or particles, give rise to surprising and fascinating phenomena.   The contributions collected in these proceedings cover several research fields, all of which deal with transport. Topics include highway, pedestrian and internet traffic, granular matter, biological transport, transport networks, data acquisition, data analysis and technological applications. Different perspectives, i.e. modeling, simulations, experiments and phenomenological observations, are considered.

  17. Gas cleaning with Granular Filters

    OpenAIRE

    Natvig, Ingunn Roald

    2007-01-01

    The panel bed filter (PBF) is a granular filter patented by A. M. Squires in the late sixties. PBFs consist of louvers with stationary, granular beds. Dust is deposited in the top layers and on the bed surface when gas flows through. PBFs are resistant to high temperatures, variations in the gas flow and hot particles. The filter is cleaned by releasing a pressure pulse in the opposite direction of the bulk flow (a puff back pulse). A new louver geometry patented by A. M. Squires is the...

  18. Peripheral granular cell odontogenic fibroma.

    Science.gov (United States)

    Rinaggio, Joseph; Cleveland, Deborah; Koshy, Ranie; Gallante, Albert; Mirani, Neena

    2007-11-01

    Peripheral odontogenic fibroma is a rare lesion that arises on the gingiva and can clinically mimic a variety of reactive lesions, benign neoplasms, and metastases. We describe a symptomatic lesion arising on the mandibular gingiva of a 58-year-old female with no history of trauma or dental disease in the area. An excisional biopsy showed the lesional stroma to contain numerous polyhedral granular cells with occasional interspersed islands of inactive odontogenic epithelium. We believe this to represent the fourth case of peripheral granular cell odontogenic fibroma to be reported in detail in the literature. PMID:17223586

  19. Continuum theory of partially fluidized granular flows

    CERN Document Server

    Aranson, I S; Aranson, Igor S.; Tsimring, Lev S.

    2002-01-01

    A continuum theory of partially fluidized granular flows is developed. The theory is based on a combination of the equations for the flow velocity and shear stresses coupled with the order parameter equation which describes the transition between flowing and static components of the granular system. We apply this theory to several important granular problems: avalanche flow in deep and shallow inclined layers, rotating drums and shear granular flows between two plates. We carry out quantitative comparisons between the theory and experiment.

  20. Continuum theory of partially fluidized granular flows

    OpenAIRE

    Aranson, Igor S.; Tsimring, Lev S

    2001-01-01

    A continuum theory of partially fluidized granular flows is developed. The theory is based on a combination of the equations for the flow velocity and shear stresses coupled with the order parameter equation which describes the transition between flowing and static components of the granular system. We apply this theory to several important granular problems: avalanche flow in deep and shallow inclined layers, rotating drums and shear granular flows between two plates. We carry out quantitati...

  1. Development of gas-fired vacuum furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Sikirica, S.J. (Gas Research Inst. (United States)); Hemsath, K.H. (Indugas Inc. (United States)); Panahi, S.K. (Southern California Gas Co. (United States))

    1994-01-01

    Vacuum processing in metallurgical heat treating processes is finding widespread acceptance. Gas-fired vacuum furnaces have several features that make them perform differently from electrically heated vacuum furnaces. This paper describes the development and preliminary performance results of a gas-fired vacuum-capable furnace system. A gas-fired vacuum furnace, with a novel high convection heating system, is show to result in lower energy operating cost and improved temperature uniformity in processes such as ion nitriding. Industrial gas-fired furnace designs, capable of operation to 1850 F, are described for horizontal and vertical configurations. (orig.)

  2. CONTROL OF FRAGMENTATION BY BLASTING

    Directory of Open Access Journals (Sweden)

    Branko Božić

    1998-12-01

    Full Text Available The degree of fragmentation influences the economy of the excavation operations. Characteristics of blasted rock such as fragment size, volume and mass are fundamental variables effecting the economics of a mining operation and are in effect the basis for evaluating the quality of a blast. The properties of fragmentation, such as size and shape, are very important information for the optimization of production. Three factors control the fragment size distribution: the rock structure, the quantity of explosive and its distribution within the rock mass. Over the last decade there have been considerable advances in our ability to measure and analyze blasting performance. These can now be combined with the continuing growth in computing power to develop a more effective description of rock fragmentation for use by future blasting practitioners. The paper describes a view of the fragmentation problem by blasting and the need for a new generation of engineering tools to guide the design and implementation of blasting operations.

  3. Influence of Addition of Briquettes with Dust Content into the Charge of Electric Induction Furnace on Cast Iron Quality

    Directory of Open Access Journals (Sweden)

    A. Pribulová

    2012-09-01

    Full Text Available Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process.Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting+5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5%bentonite and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.

  4. Segregación inherente en medios granulares / Inherent Segregation in Granular Media

    Scientific Electronic Library Online (English)

    J, Sánchez-Guzmán; G, Auvinet-Guichard.

    2011-12-01

    Full Text Available Se presenta un estudio de la segregación inherente existente en medios granulares por el efecto de la dimensión relativa de los distintos granos. Se utiliza un modelo numérico para la simulación geométrica de estructuras granulares. Tanto para la simulación como para el estudio de las estructuras gr [...] anulares se hace un amplio uso de la teoría de probabilidad. Las partículas se idealizan con círculos (modelo 2D) y esferas (modelo 3D). Se simulan materiales de granulometría estrictamente uniforme, bimodal (dos tamaños) y continua. Se proponen dos variables para medir la segregación que permiten apreciar los efectos de las variables granulométricas. En estructuras uniformes se observa la presencia de una estructuración espontánea. En las bimodales y continuas, la segregación depende principalmente de la relación entre los diámetros máximo y mínimo de las partículas. Se señalan algunas implicaciones prácticas que la segregación puede tener en los problemas de la geotecnia y otras disciplinas. Abstract in english A study of the inherent segregation within granular media due to the relative size of the different particles is presented. A numerical model is used to simulate granular structures. For both simulation and granular structures evaluations, probability theory is widely used. Particles are idealized b [...] y disks (2D model) and spheres (3D model). Strictly uniform grain size materials, bimodal (two particle sizes) and continuous are simulated. Two variables representing segregation and allowing appreciating the grain-size parameters effects are considered. In uniform materials, the presence of spontaneous structuring is observed. In bimodal and continuous materials, inherent segregation mainly depends on the ratio between maximum and minimum diameters of particle. Some practical implications of inherent segregation in geotechnical problems and other disciplines are remarked.

  5. Neurological Effects of Blast Injury

    OpenAIRE

    Hicks, Ramona R.; Fertig, Stephanie J.; Desrocher, Rebecca E.; Koroshetz, Walter J.; Pancrazio, Joseph J.

    2010-01-01

    Over the last few years, thousands of soldiers and an even greater number of civilians have suffered traumatic injuries due to blast exposure, largely attributed to improvised explosive devices in terrorist and insurgent activities. The use of body armor is allowing soldiers to survive blasts that would otherwise be fatal due to systemic damage. Emerging evidence suggests that exposure to a blast can produce neurological consequences in the brain, but much remains unknown. To elucidate the cu...

  6. Multikilowatt variable frequency microwave furnace

    International Nuclear Information System (INIS)

    In this paper, the authors describe a new type of microwave processing furnace in which the frequency can be varied continuously from 4 to 8 GHz and the power level varied from zero up to 2.5 kW. The extraordinary bandwidth of this furnace is achieved by using a traveling wave tube (TWT) amplifier originally developed for electronic warfare applications. The TWT is a linear beam device characterized by a traveling electromagnetic wave that continuously extracts energy longitudinally along the path of an electron beam. The TWT, unlike other microwave tubes such as the magnetron, klystron, gyrotron, and others, does not depend upon resonant RF fields and is therefore capable of wide bandwidth operation.operation

  7. Fluctuations in granular media

    Science.gov (United States)

    Howell, Daniel W.; Behringer, R. P.; Veje, C. T.

    1999-09-01

    Dense slowly evolving or static granular materials exhibit strong force fluctuations even though the spatial disorder of the grains is relatively weak. Typically, forces are carried preferentially along a network of "force chains." These consist of linearly aligned grains with larger-than-average force. A growing body of work has explored the nature of these fluctuations. We first briefly review recent work concerning stress fluctuations. We then focus on a series of experiments in both two- and three-dimension [(2D) and (3D)] to characterize force fluctuations in slowly sheared systems. Both sets of experiments show strong temporal fluctuations in the local stress/force; the length scales of these fluctuations extend up to 102 grains. In 2D, we use photoelastic disks that permit visualization of the internal force structure. From this we can make comparisons to recent models and calculations that predict the distributions of forces. Typically, these models indicate that the distributions should fall off exponentially at large force. We find in the experiments that the force distributions change systematically as we change the mean packing fraction, ?. For ?'s typical of dense packings of nondeformable grains, we see distributions that are consistent with an exponential decrease at large forces. For both lower and higher ?, the observed force distributions appear to differ from this prediction, with a more Gaussian distribution at larger ? and perhaps a power law at lower ?. For high ?, the distributions differ from this prediction because the grains begin to deform, allowing more grains to carry the applied force, and causing the distributions to have a local maximum at nonzero force. It is less clear why the distributions differ from the models at lower ?. An exploration in ? has led to the discovery of an interesting continuous or "critical" transition (the strengthening/softening transition) in which the mean stress is the order parameter, and the mean packing fraction, ?, must be adjusted to a value ?c to reach the "critical point." We also follow the motion of individual disks and obtain detailed statistical information on the kinematics, including velocities and particle rotations or spin. Distributions for the azimuthal velocity, V?, and spin, S, of the particles are nearly rate invariant, which is consistent with conventional wisdom. Near ?c, the grain motion becomes intermittent causing the mean velocity of grains to slow down. Also, the length of stress chains grows as ???c. The 3D experiments show statistical rate invariance for the stress in the sense that when the power spectra and spectral frequencies of the stress time series are appropriately scaled by the shear rate, ?, all spectra collapse onto a single curve for given particle and sample sizes. The frequency dependence of the spectra can be characterized by two different power laws, P??-?, in the high and low frequency regimes: ?˜2 at high ?; ?stress time series are at least qualitatively consistent with exponential fall-off at large stresses.

  8. Mechanics of Granular Materials (MGM)

    Science.gov (United States)

    Alshibli, Khalid A.; Costes, Nicholas C.; Porter, Ronald F.

    1996-01-01

    The constitutive behavior of uncemented granular materials such as strength, stiffness, and localization of deformations are to a large extend derived from interparticle friction transmitted between solid particles and particle groups. Interparticle forces are highly dependent on gravitational body forces. At very low effective confining pressures, the true nature of the Mohr envelope, which defines the Mohr-Coulomb failure criterion for soils, as well as the relative contribution of each of non-frictional components to soil's shear strength cannot be evaluated in terrestrial laboratories. Because of the impossibility of eliminating gravitational body forces on earth, the weight of soil grains develops interparticle compressive stresses which mask true soil constitutive behavior even in the smallest samples of models. Therefore the microgravity environment induced by near-earth orbits of spacecraft provides unique experimental opportunities for testing theories related to the mechanical behavior of terrestrial granular materials. Such materials may include cohesionless soils, industrial powders, crushed coal, etc. This paper will describe the microgravity experiment, 'Mechanics of Granular Materials (MGM)', scheduled to be flown on Space Shuttle-MIR missions. The paper will describe the experiment's hardware, instrumentation, specimen preparation procedures, testing procedures in flight, as well as a brief summary of the post-mission analysis. It is expected that the experimental results will significantly improve the understanding of the behavior of granular materials under very low effective stress levels.

  9. BLAST: the Redshift Survey

    CERN Document Server

    Eales, Stephen; Devlin, Mark J; Dye, Simon; Halpern, Mark; Hughes, David H; Marsden, Gaelen; Mauskopf, Philip; Moncelsi, Lorenzo; Netterfield, Calvin B; Pascale, Enzo; Patanchon, Guillaume; Raymond, Gwenifer; Rex, Marie; Scott, Douglas; Semisch, Christopher; Siana, Brian; Truch, Matthew D P; Viero, Marco P

    2009-01-01

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has recently surveyed ~=8.7 deg^2 centered on GOODS-South at 250, 350 and 500 microns. In Dye et al. (2009) we presented the catalogue of sources detected at $\\rm 5\\sigma$ in at least one band in this field and the probable counterparts to these sources in other wavebands. In this paper, we present the results of a redshift survey in which we succeeded in measuring redshifts for 83 of these counterparts. We have used the spectroscopic redshifts to carry out a test of the ability of photometric redshift methods to estimate the redshifts of dusty galaxies. We have also investigated the cases where there are two possible counterparts to the BLAST source, finding that in at least half of these there is evidence that the two galaxies are physically associated, either because they are interacting or because they are in the same large-scale structure. Finally, we have made the first direct measurements of the luminosity function in the three BLAST band...

  10. From Numeric Models to Granular System Modeling

    Directory of Open Access Journals (Sweden)

    Witold Pedrycz

    2015-03-01

    To make this study self-contained, we briefly recall the key concepts of granular computing and demonstrate how this conceptual framework and its algorithmic fundamentals give rise to granular models. We discuss several representative formal setups used in describing and processing information granules including fuzzy sets, rough sets, and interval calculus. Key architectures of models dwell upon relationships among information granules. We demonstrate how information granularity and its optimization can be regarded as an important design asset to be exploited in system modeling and giving rise to granular models. With this regard, an important category of rule-based models along with their granular enrichments is studied in detail.

  11. Automated, High Temperature Furnace for Glovebox Operation

    International Nuclear Information System (INIS)

    The U.S. Department of Energy will immobilize excess plutonium in the proposed Plutonium Immobilization Plant (PIP) at the Savannah River Site (SRS) as part of a two track approach for the disposition of weapons usable plutonium. As such, the Department of Energy is funding a development and testing effort for the PIP. This effort is being performed jointly by Lawrence Livermore National Laboratory (LLNL), Westinghouse Savannah River Company (WSRC), Pacific Northwest National Laboratory (PNNL), and Argonne National Laboratory (ANL). The Plutonium Immobilization process involves the disposition of excess plutonium by incorporation into ceramic pucks. As part of the immobilization process, furnaces are needed for sintering the ceramic pucks. The furnace being developed for puck sintering is an automated, bottom loaded furnace with insulting package and resistance heating elements located within a nuclear glovebox. Other furnaces considered for the application include retort furnaces and pusher furnaces. This paper, in part, will discuss the furnace technologies considered and furnace technology selected to support reliable puck sintering in a glovebox environment. Due to the radiation levels and contamination associated with the plutonium material, the sintering process will be fully automated and contained within nuclear material gloveboxes. As such, the furnace currently under development incorporates water and air cooling to minimize heat load to the glovebox. This paper will describe the furnace equipment and systems needed to employ a fully automated puck sintering process within nuclear gloveboxes as part of the Plutonium Immobilization Plant

  12. Vibrated granular media as experimentally realizable Granular Gases

    CERN Document Server

    McNamara, S; Namara, Sean Mc; Falcon, Eric

    2003-01-01

    We report numerical simulations of strongly vibrated granular materials designed to mimic recent experiments performed both in presence [1] or absence [2] of gravity. We show that a model with impact velocity dependent restitution coefficient is necessary to bring the simulations into agreement with experiments. We measure the scaling exponents of the granular temperature, collision frequency, impulse and pressure with the vibrating piston velocity. As the system changes from a homogeneous gas state at low density to a clustered state at high density, these exponents are all found to decrease continuously with the particle number. In absence of gravity, a loose cluster appears near the upper wall, opposite the piston, and acts as a buffer for fastest particles leading to unexpected non-extensive scaling exponents ; whereas in presence of gravity, the cluster bounces as a single inelastic body. All these results differ significantly from classical inelastic hard sphere kinetic theory and previous simulations, ...

  13. Vibration and noise from blasting

    Energy Technology Data Exchange (ETDEWEB)

    Siskind, D.E.

    1982-01-01

    Adverse environmental effects from blasting continue to be a major problem for the mining industry, the public living near mining operations, and the governmental agencies responsible for setting environmental standards. The Bureau of Mines has established a comprehensive blasting research program dealing with the many technical aspects of generation and propagation of ground vibrations and airblast, structure response and damage, and proper instrumentation.

  14. Blast optimization at Kriel Colliery

    Scientific Electronic Library Online (English)

    A.M., Neale.

    2010-04-01

    Full Text Available Kriel Colliery has experienced some sub-standard blast results on the overburden. Blast results are considered poor when the fragmentation is too big, back break into the new highwall, capping is experienced and/or excess overburden material is thrown into the void. Poor blasting leads to lower prod [...] uctivity, equipment breakdowns, and poor drilling and blasting results on the adjacent blast, contamination of coal or loss of coal. A simulation was developed in Microsoft Excel to model blasting results while changing various parameters. From the simulation results, it could be seen that a change of blast design could be beneficial. As an example, smaller drilling patterns were simulated (10 m x 10 m to 8 m x 8 m, and 8 m x 8 m to 7 m x 7 m in Pit 5 and Pit 6 respectively) in combination with changes in explosives (P700 emulsion vs. ANFO) and drill bit diameter (311mm vs. 251mm). The results show that each of the options has a specific scenario that will be most beneficial to the mine. These results are quite specific and subject to variable inputs. The purpose of the example is to demonstrate how the simulation can be used as a tool to asses blast design variations

  15. Magnetohydrodynamic processes in arc and electroslag furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Volokhonsky, L. [Joint-Stock Company, Thermoecology at the VNIIETO (Russian Federation); Dementyev, S. [Institute of Physics, Latvian Academy of Sciences (Latvia); Scherbinin, E.

    1992-12-31

    Qualitative and quantitative investigations of the flow structures in melts of electrometallurgic furnaces were conducted. Convections caused by an electromagnetic field from current passing through a melting furnace bath were executed by physical simulation method. Measurements were carried out by means of a fibre optical converter in mercury baths. Movements were studied and velocities were defined at electroslag furnaces with one or two electrodes, DC arc furnaces, 3-phase arc furnaces and ore-smelting furnaces. A velocity profile in the boundary layer was observed. Measurements have lead to the regulation of processes of melt-down and refining the current in conducting and non-conducting melts. This contributed to improvement of the quality of the finished products, and resulted in lowering the consumption of electric power. 2 refs, 8 figs.

  16. Crystal growth furnace with trap doors

    Science.gov (United States)

    Sachs, Emanual M. (Watertown, MA); Mackintosh, Brian H. (Lexington, MA)

    1982-06-15

    An improved furnace is provided for growing crystalline bodies from a melt. The improved furnace is characterized by a door assembly which is remotely controlled and is arranged so as to selectively shut off or permit communication between an access port in the furnace enclosure and a hot zone within that enclosure. The invention is especially adapted to facilitate use of crystal growing cartridges of the type disclosed in U.S. Pat. No. 4,118,197.

  17. Thermal analysis in fire-resistance Furnace

    OpenAIRE

    Piloto, P. A. G.; Mesquita, L.M.R.; Pereira, Alexandre Augusto

    2009-01-01

    Fire resistance rating of building construction elements is defined under fire-resistance test furnace. The geometry and shape of fire-resistance furnaces is not defined by any prescriptive document, being necessary to comply thermally with specified nominal fire curves, such as ISO 834 or hydrocarbon [1,2]. This research work intends to measure temperatures inside furnace volume, using sixteen plate thermocouples to compare average temperature in four planes. Those planes are ...

  18. 30 CFR 75.1323 - Blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting circuits. 75.1323 Section 75.1323... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made...

  19. Bio furnace fuel test final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-12-15

    The use of biodiesel is expected to grow in North America as a result of federal, provincial, and state mandates. In addition to being used as fuel for diesel-powered vehicles, biodiesel is also suitable as a blending component in furnace fuel oil. Studies have shown that 5 percent biodiesel blends are compatible with standard flame-sensors. This paper provided details of a test program conducted to evaluate the long-term performance of late-model furnaces using bio-furnace fuel. The test facility was equipped with 3 Kerr furnaces. The tests consisted of three 40 day cycles conducted to simulate spring, fall, moderate severity and wind cold snap operations using a furnace fuel blended with canola methyl ester (CME), soybean methyl ester (SME) and tallow methyl ester (TME). All bio-furnace fuels met the CAN/CGSB-3.2 Standard. Furnace efficiency, excess air, flue gas composition and temperature, smoke number, breech draft and breech temperature, CAD cell resistance, and pump and nozzle temperature were monitored on a weekly basis. Results of the study showed that there is negligible impact on furnace operation and performance with bio-furnace fuels up to B10. Saturated monoglycerides were deposited on the drain lines of 2 fuel tanks. 8 refs., 13 tabs., 27 figs. 50 appendices.

  20. Measurement of airflow in residential furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Biermayer, Peter J.; Lutz, James; Lekov, Alex

    2004-01-24

    In order to have a standard for furnaces that includes electricity consumption or for the efficiency of furnace blowers to be determined, it is necessary to determine the airflow of a furnace or furnace blower. This study focused on airflow testing, in order to determine if an existing test method for measuring blower airflow could be used to measure the airflow of a furnace, under conditions seen in actual installations and to collect data and insights into the operating characteristics of various types of furnace blowers, to use in the analysis of the electricity consumption of furnaces. Results of the measured airflow on furnaces with three types of blower and motor combinations are presented in the report. These included: (1) a forward-curved blower wheel with a typical permanent split capacitor (PSC) motor, (2) a forward-curved blower wheel with an electronically-commutated motor (ECM), and (3) a prototype blower, consisting of a backward-inclined blower wheel matched to an ECM motor prototype, which is being developed as an energy-saving alternative to conventional furnace blowers. The testing provided data on power consumption, static and total pressure, and blower speed.

  1. Cast construction elements for heat treatment furnaces

    OpenAIRE

    B. Piekarski; A. Drotlew

    2011-01-01

    The study presents sketches and photos of the cast creep-resistant components used in various types of heat treatment furnaces. The shape of the elements results from the type of the operation carried out in the furnace, while dimensions are adjusted to the size of the furnace working chamber. The castings are mainly made from the high-alloyed, austenitic chromium-nickel or nickel-chromium steel, selecting the grade in accordance with the furnace operating conditions described by the rated te...

  2. Driven low density granular mixtures

    CERN Document Server

    Pagnani, R; Puglisi, A

    2002-01-01

    We study the steady state properties of a 2D granular mixture in the presence of energy driving by employing simple analytical estimates and Direct Simulation Monte Carlo. We adopt two different driving mechanisms: a) a homogeneous heat bath with friction and b) a vibrating boundary (thermal or harmonic) in the presence of gravity. The main findings are: the appearance of two different granular temperatures, one for each species; the existence of overpopulated tails in the velocity distribution functions and of non trivial spatial correlations indicating the spontaneous formation of cluster aggregates. In the case of a fluid subject to gravity and to a vibrating boundary, both densities and temperatures display non uniform profiles along the direction normal to the wall, in particular the temperature profiles are different for the two species while the temperature ratio is almost constant with the height. Finally, we obtained the velocity distributions at different heights and verified the non gaussianity of ...

  3. Dilatancy in slow granular flows.

    Science.gov (United States)

    Kabla, Alexandre J; Senden, Tim J

    2009-06-01

    When walking on wet sand, each footstep leaves behind a temporarily dry impression. This counterintuitive observation is the most common illustration of the Reynolds principle of dilatancy: that is, a granular packing tends to expand as it is deformed, therefore increasing the amount of porous space. Although widely called upon in areas such as soil mechanics and geotechnics, a deeper understanding of this principle is constrained by the lack of analytical tools to study this behavior. Using x-ray radiography, we track a broad variety of granular flow profiles and quantify their intrinsic dilatancy behavior. These measurements frame Reynolds dilatancy as a kinematic process. Closer inspection demonstrates, however, the practical importance of flow induced compaction which competes with dilatancy, leading more complex flow properties than expected. PMID:19658906

  4. Thermoelectric performance of granular semiconductors

    OpenAIRE

    Glatz, Andreas; Beloborodov, I. S.

    2009-01-01

    We study thermoelectric properties of granular semiconductors with weak tunneling conductance between the grains, g_t < 1. We calculate the thermopower and figure of merit taking into account the shift of the chemical potential and the asymmetry of the density of states in the vicinity of the Fermi surface due to n- or p-type doping in the Efros-Shklovskii regime for temperatures less than the charging energy. We show that for weakly coupled semiconducting grains the figure ...

  5. Paediatric laryngeal granular cell tumour

    Directory of Open Access Journals (Sweden)

    Dauda Ayuba

    2009-01-01

    Full Text Available Granular cell tumour (GCT affecting the larynx is not common, especially in children. Most cases are apt to be confused with respiratory papilloma and may even be mistaken for a malignant neoplasia. We present a case of laryngeal GCT in a 12-year-old child to emphasize that the tumour should be regarded in the differential of growths affecting the larynx in children.

  6. Granularity-Adaptive Proof Presentation

    OpenAIRE

    Schiller, Marvin; Benzmueller, Christoph

    2009-01-01

    When mathematicians present proofs they usually adapt their explanations to their didactic goals and to the (assumed) knowledge of their addressees. Modern automated theorem provers, in contrast, present proofs usually at a fixed level of detail (also called granularity). Often these presentations are neither intended nor suitable for human use. A challenge therefore is to develop user- and goal-adaptive proof presentation techniques that obey common mathematical practice. We present a flexib...

  7. Inverse grading in granular flow

    OpenAIRE

    Kern, Martin

    2000-01-01

    The current work concerns with the parametrical dependencies of inverse grading in granular flows from material properties of individual particles involved in the flow. The investigations were initiated and motivated by the search for an explanation of the function principle of the avalanche airbag, which prevents a skier from going under in a flowing avalanche. The functionality of the avalanche airbag cannot be understood in the frame of the classical hydrodynamical avalanche models: the hy...

  8. Instability in shocked granular gases

    Science.gov (United States)

    Sirmas, Nick; Radulescu, Matei

    2013-11-01

    Shocks in granular media, such as vertically oscillated beds, have been shown to develop instabilities. Similar jet formation has been observed in explosively dispersed granular media. In the current study, we investigate the origin of this instability. Our previous work addresses this instability by performing discrete-particle simulations of inelastic media undergoing shock compression. By allowing finite dissipation within the shock wave, instability manifests itself as distinctive high density non-uniformities and convective rolls within the shock structure. By analyzing the time evolution of the material undergoing the shock wave compression and further relaxation, we found that the clustering instability is the dominant mechanism controlling this instability. In the present study we extend this work to investigate the instability at the continuum level. We model the Euler equations for granular gases with a modified cooling rate to include an impact velocity threshold necessary for inelastic collisions. Our results demonstrate a fair agreement between the continuum and discrete-particle models. Slight discrepancies, such as higher frequency non-uniformities in our continuum results may be attributed to the absence of viscous effects.

  9. The use of computer blast simulations to improve blast quality

    International Nuclear Information System (INIS)

    Atomic Energy of Canada Limited is constructing an Underground Research Laboratory (URL) as part of a comprehensive program to evaluate the concept of nuclear fuel waste disposal deep in crystalline rock formations. Careful blasting methods have been used to minimize damage to the excavation surfaces. Good wall quality is desirable in any excavation. In excavations required for nuclear waste disposal, the objective will be to minimize blast-induced fractures which may complicate the sealing requirements necessary to control subsequent movement of groundwater around a sealed disposal vault. The construction of the URL has provided an opportunity for the development of controlled blasting methods, especially for drilling accuracy and optimization of explosive loads in the perimeter and cushion holes. The work has been assisted by the use of blast simulations with the mathematical model Blaspa. This paper reviews the results of a recent project to develop a controlled method of full-face blasting, and compares the observed field results with the results of a blast simulator called Blaspa. Good agreement is found between the two, and the Blaspa results indicate quantitatively how the blasting may induce damage in the final excavation surface. In particular, the rock in the final wall may be stressed more severely by the cushion holes than by the perimeter holes. Bootleg of the rock between the perimeter and cushion rows occurs when the burst-out velocity imparted to it by the explosive loads in the perimeter holes is inadequate. In practice, these findings indicate that quantitative rock stress and rock burst-out velocity criteria can be established to minimize wall damage and bootleg. Thus, blast simulations become an efficient way to design controlled blasting and to optimize quality of the excavation surface

  10. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    International Nuclear Information System (INIS)

    The objective of this project is to improve the productivity and lower the expense of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCBs, and lead-based paint and provides worker protection by continuously recycling the material and dust for the decontamination tasks. The proposed work would increase the cleaning rate and provide safe and cost-effective decontamination of the DOE sites. This work focuses on redesigning and improving existing vacuum blasting technology including blast head nozzles, ergonomic handling of the blast head by reducing its weight; brush-ring design, vacuum level regulator, efficiency of the dust separator, and operational control sensors. The redesign is expected to enhance the productivity and economy of the vacuum blasting system by at least 50% over current vacuum blasting systems. There are three phases in the project. Phase I consists of developing and testing mathematical models. Phase II consists of pre-prototype design and fabrication and pre-prototype unit testing. Phase III consists of prototype design and field verification testing. In phase I, mathematical models are developed and analyzed for the nozzle, blast head, wind curtain, and dust separator, first as individual devices and then combined as an integrated model. This allows study of respective airflow and design parameters. The Contractor shall, based on the results of the mathematical modeling studies, design experimental models of the components and test these models. In addition, the Contractor shall develop sensors to detect the relationship of the blast head to the blast surfaces and controls to minimize the dependency on an operator's skill and judgment to obtain optimum positioning, as well as real-time characterization sensors to determine as the blast head is moving the depth to which coatings must be removed, thereby improving production and minimizing waste. In phase II, the Contractor shall design and construct a pre-prototype of the nozzle, blast head with wind curtain, sensors, and dust separator and test this system to assess the performance of the new design under controlled conditions at the contractor's facility. In phase III, the Contractor shall design and construct a prototype of the High Productivity Vacuum Blasting System, based on the results of the pre-prototype design and testing performed. This unit will be a full-scale prototype and will be tested at a designated Department of Energy (DOE) facility. Based on the results, the system performance, the productivity, and the economy of the improved vacuum blasting system will be evaluated

  11. Centrifugal shot blast system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997.

  12. Centrifugal shot blast system

    International Nuclear Information System (INIS)

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997

  13. A stochastic flow rule for granular materials

    OpenAIRE

    Kamrin, Ken; Bazant, Martin Z.

    2006-01-01

    There have been many attempts to derive continuum models for dense granular flow, but a general theory is still lacking. Here, we start with Mohr-Coulomb plasticity for quasi-2D granular materials to calculate (average) stresses and slip planes, but we propose a "stochastic flow rule" (SFR) to replace the principle of coaxiality in classical plasticity. The SFR takes into account two crucial features of granular materials - discreteness and randomness - via diffusing "spots"...

  14. Continuum description of avalanches in granular media

    OpenAIRE

    Aranson, Igor S.; Tsimring, Lev S

    2000-01-01

    We develop a continuum description of partially fluidized granular flows. Our theory is based on the hydrodynamic equation for the flow coupled with the order parameter equation which describes the transition between flowing and static components of the granular system. This theory captures important phenomenology recently observed in experiments with granular flows on rough inclined planes (Daerr and Douady, Nature (London) v. 399, 241 (1999)): layer bistability, and transi...

  15. Viscosity evolution of anaerobic granular sludge

    OpenAIRE

    Pevere, A.; Guibaud, G.; Hullebusch, E.D., van; Lens, P. N. L.; Baudu, M.

    2006-01-01

    The evolution of the apparent viscosity at steady shear rate of sieved anaerobic granular sludge (20¿315 ¿m diameter) sampled from different full-scale anaerobic reactors was recorded using rotation tests. The ¿limit viscosity¿ of sieved anaerobic granular sludge was determined from the apparent viscosity. The limit viscosity values depended on the applied shear rate, indicating a non-Newtonian behaviour of anaerobic granular sludge. The tests to determine the apparent viscosity values were c...

  16. Granular flow modelled by Brownian particles

    OpenAIRE

    Riethmueller, T. L.; Rosenkranz, D.; Schimansky-Geier, L.

    2008-01-01

    Granular flows through pipes show interesting phenomena, e.g. clogging and density waves, 1/f-noise. These things are fairly good studied by computer-experiments, but there is a lack in theoretical and analytical consideration. We introduce a simple "minimal" model describing such a flow of granular particles and examine the stability of an initially homogeneous system against perturbations. In order to define the collisions between the granular particles we use two differen...

  17. Anisotropy of weakly vibrated granular flows

    Science.gov (United States)

    Wortel, Geert H.; van Hecke, Martin

    2015-10-01

    We experimentally probe the anisotropy of weakly vibrated flowing granular media. Depending on the driving parameters—flow rate and vibration strength—this anisotropy varies significantly. We show how the anisotropy collapses when plotted as a function of the driving stresses, uncovering a direct link between stresses and anisotropy. Moreover, our data suggest that for small anisotropies, the shear stresses vanish. Anisotropy of the fabric of granular media thus plays a crucial role in determining the rheology of granular flows.

  18. Size separation in vibrated granular matter

    OpenAIRE

    Kudrolli, A.

    2004-01-01

    We review recent developments in size separation in vibrated granular materials. Motivated by a need in industry to efficiently handle granular materials and a desire to make fundamental advances in non-equilibrium physics, experimental and theoretical investigations have shown size separation to be a complex phenomena. Large particles in a vibrated granular system invariably rise to the top. However, they may also sink to the bottom, or show other patterns depending on subt...

  19. On numerical simulation of granular flow

    OpenAIRE

    Schmidt , Sebastian

    2009-01-01

    The goal of this work is the development and investigation of an interdisciplinary and in itself closed hydrodynamic approach to the simulation of dilute and dense granular flow. The definition of “granular flow” is a nontrivial task in itself. We say that it is either the flow of grains in a vacuum or in a fluid. A grain is an observable piece of a certain material, for example stone when we mean the flow of sand. Choosing a hydrodynamic view on granular flow, we treat the granular material ...

  20. Multi-granular Perspectives on Covering

    CERN Document Server

    Chen, Wan-Li

    2011-01-01

    Covering model provides a general framework for granular computing in that overlapping among granules are almost indispensable. For any given covering, both intersection and union of covering blocks containing an element are exploited as granules to form granular worlds at different abstraction levels, respectively, and transformations among these different granular worlds are also discussed. As an application of the presented multi-granular perspective on covering, relational interpretation and axiomization of four types of covering based rough upper approximation operators are investigated, which can be dually applied to lower ones.