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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

Energy Conservation for Granular Coal Injection into a Blast Furnace  

Science.gov (United States)

Due to the lack of knowledge regarding the combustion of granular coal injected into a blast furnace, injection characteristics of granular coal were first studied through proximate analysis, element analysis, and research of explosivity, ignition point, meltability of ash, grindability, calorific value, etc. Using a sampling device in the raceway combined with petrographic analysis, during the combustion process of granular coal with high crystal water and volatile in raceway, cracks and bursts were found, leading to a reduction of particle size. Based on a model of mass control and dynamic theory of particle combustion, the transition dynamic model for cracking in combustion of granular coal was found, and the critical value of cracking ratio (?P) for granular coal combustion in the raceway was calculated. Finally, the utilization ratio and energy efficiency of granular coal used in the blast furnace were discussed, offering theoretical foundation and technical support for intensifying granular coal combustion and promoting granular coal injection.

Guo, Hongwei; Su, Buxin; Zhang, Jianliang; Shao, Jiugang; Zuo, Haibin; Ren, Shan

2012-08-01

3

An update on blast furnace granular coal injection  

Energy Technology Data Exchange (ETDEWEB)

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.

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

4

Blast furnace granular coal injection project. Annual report, January--December 1993  

Energy Technology Data Exchange (ETDEWEB)

This initial annual report describes the Blast Furnace Granular Coal Injection project being implemented at Bethlehem Steel Corporation`s (BSC) Burns Harbor, Indiana, plant. This installation will be the first in the United States to employ British Steel technology that uses granular coal to provide part of the fuel requirement of blast furnaces. The project will demonstrate/assess a broad range of technical/economic issues associated with the use of coal for this purpose. These include: coal grind size, coal injection rate, coal source (type) and blast furnace conversion method. Preliminary Design (Phase 1) began in 1991 with detailed design commencing in 1993. Construction at Burns Harbor (Phase 2) began in August 1993. Construction is expected to complete in the first quarter of 1995 which will be followed by the demonstration test program (Phase 3). Progress is described.

1994-06-01

5

Blast furnace granular coal injection project. Annual report, January--December 1994  

Energy Technology Data Exchange (ETDEWEB)

This annual report describes the Blast Furnace Granular Coal Injection project being implemented at Bethlehem Steel Corporation`s (BSC) Burns Harbor Plant. The project is receiving cost-sharing from the US Department of Energy (DOE), and is being administrated by the Morgantown Energy Technology Center in accordance with the DOE Cooperative Agreement No. DE-FC21-91MC27362. This installation is the first in the United States to employ British Steel technology that uses granular coal to provide part of the fuel requirement of blast furnaces. The project will demonstrate/assess a broad range of technical/economic issues associated with the use of coal for this purpose. These include: coal grind size, coal injection rate, coal source (type) and blast furnace conversion method. To achieve the program objectives, the demonstration project is divided into the following three Phases: Phase I -- design; Phase II -- construction; and Phase III -- operation. Preliminary design (Phase I) began in 1991 with detailed design commencing in 1993. Construction at Burns Harbor (Phase II) began in August 1993 and was completed at the end of 1994. A 100% construction review meeting was held in December and attended by representatives of DOE, Fluor Daniel and Bethlehem Steel. The coal preparation mills were started up in December, 1994, and the first coal was injected into ``D`` blast furnace on December 19, 1994. Near the end of the year, the grinding mills and injection facility were being prepared for performance testing during the first quarter of 1995. The demonstration test program (phase III) will start in the fourth quarter of 1995.

NONE

1995-07-01

6

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

7

Alkaline carbonates in blast furnace process  

Directory of Open Access Journals (Sweden)

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.

P. Besta

2014-10-01

8

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

9

The use of blast furnace slag  

Directory of Open Access Journals (Sweden)

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.

V. Václavík

2012-10-01

10

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

11

Quality of coal for blast furnace injection  

Energy Technology Data Exchange (ETDEWEB)

CANMET Energy Technology Centre (CETC) has been involved in a research program to evaluate the suitability of various coals for blast furnace injection. The primary objectives of this program are to provide essential information on coal combustion in the blast furnace and to establish proper criteria for evaluating and selecting coals for blast furnace injection. The program comprises three parts. Parts one and two have been completed. To date, the program has encompassed both a theoretical assessment of cooling and coke replacement characteristics of coals using CETC`s computer model and an experimental determination of the combustibility of coals of different ranks and particle sizes as well as the influence of oxygen enrichment on burnout. The experimental part was conducted in CETC`s pilot-scale injection unit that simulates blast furnace blowpipe-tuyere conditions. Part three now being developed will incorporate results of experimental trials into a blast furnace raceway model in order to predict total combustibility of coals at different blast furnace operating conditions. This paper describes CETC`s facility and methodology of work, and presents and discusses results.

Hutny, W.P.; Giroux, L.; MacPhee, J.A.; Price, J.T. [CANMET Energy Technology Centre/Natural Resources Canada, Ottawa, Ontario (Canada)

1996-12-31

12

Coal combustion under blast furnace raceway conditions  

Energy Technology Data Exchange (ETDEWEB)

Over the past fifteen years there has been a substantial increase in both the number of blast furnaces using the direct injection of coal and the levels of injection employed. This paper summarises the results obtained from pilot plant and plant studies used by British Steel in order to study coal combustion under blast furnace conditions and support the plant activities. The paper also describes the new laboratory scale apparatus now being constructed by British Steel Technical which will be used to supply information and samples for a joint project supported by the UK Department of Trade and Industry. The technical programme for the project is described. 14 figs., 8 figs., 2 tabs.

Atkinson, C.J.; Bennington, C.R.; Hitchinson, C.; Willmers, R.R. [British Steel Technical, Middlesbrough (United Kingdom). Energy Refractories and Coke Dept.

1995-08-01

13

Blast Furnace Granulated Coal Injection  

Energy Technology Data Exchange (ETDEWEB)

Production levels on each furnace exceeded 7000 NTHM/day during July. The combined production of 14,326 was a result of lower coke rates and below average delay rates on both furnaces, The combined production was at its highest level since September 1997. In August, the combined productivity declined to less than 13,500 NTHM/day. Although D furnace maintained a production rate in excess of 7000 NTHM/day, C furnace was lower because of a castfloor breakout and subsequent five day repair from August 26-30. Despite the lower productivity in August, injected coal and furnace coke rates were very good during the month. During September, the operation was difficult as a result of higher delays on both furnaces. The combined average monthly delay rate was considerably above the twenty-month average of 113 minutes per day and the combined average monthly production was less than 14,000 NTHM/day. Higher furnace coke rates at lower coal injection levels also contributed to the decrease. Additionally, the coke rate on both furnaces was increased substantially and the injected coal rate was decreased in preparation for the high volatile Colorado coal trial that started on September 28. The furnace process results for this quarter are shown in Tables 1A and 1B. In addition, the last twelve months of injected coal and coke rates for each furnace are shown in Figures 1 and 2.

NONE

1998-09-30

14

Blast furnace on-line simulation model  

Science.gov (United States)

A mathematical model of the ironmaking blast furnace (BF) is presented. The model describes the steady-state operation of the furnace in one spatial dimension using real process data sampled at the steelworks. The measurement data are reconciled by an interface routine which yields boundary conditions obeying the conservation laws of atoms and energy. The simulation model, which provides a picture of the internal conditions of the BF, can be used to evaluate the current state of the process and to predict the effect of operating actions on the performance of the furnace.

Saxén, Henrik

1990-10-01

15

Blast-furnace crucibles made of coal  

Energy Technology Data Exchange (ETDEWEB)

Discusses conditions that allow a heat insulating quasi-refractory layer of slag or frozen metal to form between the coal lining of the hearth of a blast furnace and the molten iron. Such layers form relatively easily owing to the coal lining being cooled from outwards. Currents of molten metal are also considered to be a factor that contributes to crucible destruction. Research work into that factor is reviewed and its results are outlined. It was found that increased distance between blast-furnace bottom and the dead charge contributes to reduction in the velocity of pig iron streams. Hearths of new blast furnaces are built at Thyssen with a depth increased by about 1 m. Improved linings of crucibles made of coal are also considered. A design applied at the blast-furnace no 6 at the Hamborn Steelworks of Thyssen is shown where the crucible made of graphite and coal is protected by a ceramic cup made of mullite. 3 refs.

Sabela, W. (Politechnika Czestochowska (Poland))

1992-01-01

16

Dependence of coke consumption and blast furnace output on intensity of blast furnace operation  

Energy Technology Data Exchange (ETDEWEB)

Factors are discussed which influence coke consumption by a blast furnace: furnace capacity, permeability of the charge to gases, and coke quality. Effects of grain size distribution of coke, in particular, content of coke fines with a diameter below 5 mm, coke mechanical properties (the M40 compression strength index, coke abrasion wear), coke reactivity and ash content on coke consumption rates and blast furnace output are analyzed. Ash content increase in coke increases coke consumption rates (on the average a 1% increase in ash causes a consumption rate increase of 2 to 2.5%). Evaluations carried out in Poland by Janik and Pawlik show that ash content increase in coke from 8 to 12% improves coke combustion intensity which partly compensates the negative effects of a high ash content. Factors which influence coke consumption rates are analyzed using a blast furnace with a capacity of 862 m/sup 3/. Intensity of blast furnace operation is determined as the coke consumption rate per 1 m/sup 3/ furnace volume in 24 h. Evaluations show that coke consumption is minimum when 0.7 t coke is used. Blast furnace output is maximum when 0.78 t coke is used. The results of evaluations are given in a table and diagram. 5 references.

Stec, R.; Malarski, T.; Binkowski, W.

1985-05-01

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

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

19

Current situation and predictions further development of blast furnace technology  

Directory of Open Access Journals (Sweden)

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.

J. Mróz

2012-12-01

20

Thermomechanical modelling of a blast furnace hearth  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The goal of this work is to develop a thermo-mechanical model of a blast furnace hearth able to estimate the stress state in service. To identify the behaviour of bricks, mortars and ramming mix, characterization tests have been developed for temperatures up to 1500°C. A modified Cam-clay model is identified for the ramming mix. The masonry modelling is based on a macroscopic approach where bricks and mortars are replaced by a set of equivalent homogeneous materials accounting for the differ...

Brulin, Je?ro?me; Rekik, Amna; Blond, Eric; Josserand, Laurent; Gasser, Alain; Roulet, Fre?de?ric

2011-01-01

 
 
 
 
21

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

22

Blast furnace lining and cooling technology: experiences at Corus IJmuiden  

Energy Technology Data Exchange (ETDEWEB)

This article describes the blast furnace lining and cooling concept as originally developed and applied by Hoogovens (Corus IJmuiden). The technology has also been applied by Danieli Corus in all its blast furnace projects executed in the last 25 years. The technology has helped Corus increase its PCI rate to over 200 kg/thm. 4 refs., 13 figs., 1 tab.

Stokman, R.; van Stein Cellenfels, E.; van Laar, R.

2004-11-01

23

Modelling ironmaking blast furnace: Solid flow and thermochemical behaviours  

Science.gov (United States)

Ironmaking blast furnace is a counter-, co-, cross-current moving bed reactor, where solid particles are charged at the furnace top forming a downward moving bed while gas are introduced at the lower part of furnace and travels upward through the solid bed of varying porosity, reducing solid ore to liquid iron at the cohesive zone. These three phases interact intensely. In this paper, a three-dimensional mathematical model is developed. The model describes the motion of solid and gas, based on continuum approach, and implements the so-called force balance model for the liquid flow. The model is applied to a blast furnace, where raceway cavity is considered explicitly. The results demonstrate and characterize the key multiphase flow patterns of solid-gas-liquid at different regions inside the blast furnace, in particular solid flow and associated thermochemical behaviours of solid particles. This model offers a costeffective tool to understand and optimize blast furnace operation.

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

2013-06-01

24

Blast Furnace Granulated Coal Injection System Demonstration Project public design report. Topical report  

Energy Technology Data Exchange (ETDEWEB)

The public design report describes the Blast Furnace Granulated Coal Injection (BFGCI) project under construction at Bethlehem Steel Corporation`s (BSC) Burns Harbor, Indiana, plant. The project is receiving cost-sharing from the U.S. Department of Energy (DOE), and is being administrated by the Morgantown Energy Technology Center in accordance with the DOE Cooperative Agreement No. DE-FC21-91MC27362. The project is the first installation in the United States for the British Steel technology using granular coal in blast furnaces. The objective is to demonstrate that granular coal is an economic and reliable fuel which can successfully be applied to large North American blast furnaces. These include: coal grind size, coal injection rate, coal source (type) and blast furnace conversion method. To achieve the program objectives, the demonstration project is divided into the following three Phases: Phase I-Design; Phase II-Procurement & Construction; and Phase III-Operation. Preliminary design (Phase I) began in 1991 with detailed design commencing in April 1993. Construction at Burns Harbor (Phase II) began August 1993. Construction is expected to be complete in the first quarter of 1995 which will be followed by a demonstration test program (Phase III).

NONE

1995-03-01

25

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

26

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

27

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)

28

Use of pea coke in a blast furnace with a volume of 3,200 m[sup 3] as a partial replacement for blast furnace coke  

Energy Technology Data Exchange (ETDEWEB)

Evaluates effects of partial replacement of standard blast furnace coke with pea coke with a grain size from 10 to 245 mm on operation of a blast furnace and on coke consumption rates. Coke abrasion was investigated under laboratory conditions at 1,000 C. Reactivity of pea coke and that of standard blast furnace coke was comparatively evaluated at 900 C, 1,000 C and 1,100 C. Effects of partial replacement of standard blast furnace coke with pea coke were investigated under operating condition in a blast furnace with a volume of 3,200 m[sup 3]. Investigations showed that replacing 8-9% blast furnace coke with pea coke did not negatively influence the permeability of a blast-furnace charge. Pea coke should be characterized by reactivity higher than that of standard blast furnace coke. 3 refs.

Misiun, T.; Wozniacki, W.; Wyroslak, J. (Instytut Metalurgii Zelaza, Gliwice (Poland))

1993-03-01

29

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

30

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

31

Silicon behaviour at the blast furnace process  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: Views on the reduction of SiO2 at the blast furnace process began to change in the mid 70s. Nowadays it is claimed that the silicon appears in the metal not only from the slag SiO2 reduction at the liquid phase, but also from a gaseous SiO. Presented in this paper, laboratory tests were aimed on finding the effect of temperature and MgO containing in the slag on the dynamics of the Si transition to the pig iron at the liquid phase at time when slag lies on metal.Design/methodology/approach: Laboratory tests carried out in laboratory on devices AGH described in detail in other studies such as [8-11]. Metal used in the study obtained by carbonizing the carbon-iron saturation assuming the values given by J. Chipman [7].Findings: Observations of industrial units in combination with laboratory tests allowed us to approximately determine the contribution of silicon from the gaseous SiO in hot metal.Research limitations/implications: Si content in the metal after the test at a constant temperature is less than taping pig iron of about 0.15 to 0.35%. This means that in addition to the reduction reaction of the silica source of silicon in the slag is reduced gaseous SiO , which is in line with those of the authors [2-5, 8-10]. This will also be the subject of the next stage of research.Practical implications: As a result, developed guidelines and proposals for the conduct of blast-furnace technology to minimize Si in pig iron.Originality/value: The AGH research team has approached to issue of SiO2 reduction complexly. The work is divided into stages. Laboratory studies combined with industry specific observations. As a result of this approach to work is possible to develop a practical technology to minimize silicon in the pig iron. Articles published in reputable journals on similar or related topics do not include all issues.

A. Klimczyk

2012-12-01

32

Use of PCI in blast furnaces  

Energy Technology Data Exchange (ETDEWEB)

Increasing steel demand and growing competition from scrap-based mini-mills is forcing blast furnace (BF) based plants to improve their performance in order to reduce operating costs and, at the same time, increase productivity. One way to achieve this is by injecting pulverised coal directly into the BF. Injection of coal causes a number of changes within the BF, some of which can be detrimental. This report begins by outlining some of the technical issues associated with high pulverised coal injection (PCI) rates. It then discusses the effect of coal quality on the performance of BFs with the emphasis on the properties of coal that influence its selection. The requirements relating to coke quality have become more stringent at high PCI rates, and this is discussed, along with the quality of iron ore. The pulverisation and injection of coal is examined. Coal combustion is an important parameter as it affects the amount of coal that can be injected. It produces, along with coke combustion, both heat and reducing gases for the ironmaking process. Coal combustion within the raceway and the consumption of unburnt char outside the raceway are discussed. Finally, the transfer of silicon and sulphur from coal to the hot metal (pig iron), which adversely affects its quality, is described. The report concludes that blending offers advantages in improving the performance of coals. Its importance is likely to increase as injection rates approach the theoretical maximum and will provide furnace operators with the flexibility in coal selection to meet their particular needs. With better predication and improved understanding of the effect of coal properties and how operating conditions can be optimised, there is the potential to identify suitable, as well as cheaper, coals. This could provide significant cost savings whilst maintaining a high productivity. 184 refs., 23 figs., 10 tabs.

Carpenter, A.M. [IEA Clean Coal Centre, London (United Kingdom)

2006-09-15

33

Modelling of multiphase flow in ironmaking blast furnace  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model for the four-phase (gas, powder, liquid, and solids) flow in a two-dimensional ironmaking blast furnace is presented by extending the existing two-fluid flow models. The model describes the motion of gas, solid, and powder phases, based on the continuum approach, and implements the so-called force balance model for the flow of liquids, such as metal and slag in a blast furnace. The model results demonstrate a solid stagnant zone and dense powder hold-up region, as well as a dense liquid flow region that exists in the lower part of a blast furnace, which are consistent with the experimental observations reported in the literature. The simulation is extended to investigate the effects of packing properties and operational conditions on the flow and the volume fraction distribution of each phase in a blast furnace. It is found that solid movement has a significant effect on powder holdup distribution. Small solid particles and low porosity distribution are predicted to affect the fluid flow considerably, and this can cause deterioration in bed permeability. The dynamic powder holdup in a furnace increases significantly with the increase of powder diameter. The findings should be useful to better understand and control blast furnace operations.

Dong, X.F.; Yu, A.B.; Burgess, J.M.; Pinson, D.; Chew, S.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia). School for Material Science and Engineering

2009-01-15

34

Modelling of turbulent combustion blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

Metallurgical coke is a traditional fuel in blast furnaces. However, coking is an expensive and air polluting process. There are significant environmental and economical reasons to minimise coke consumption in iron making. It is possible to inject some auxiliary fuel through a blowpipe into a raceway and reduce the mount of coke needed in the process. Various kinds of fuels have been used as an auxiliary fuel: oil, coal, natural gas, tar and different kinds of emulsions. The aim of this research was to model flow and combustion phenomena in the raceway area, when auxiliary fuel is heavy residual oil. The research started June 1994 in the SULA 2 -programme. After that Rautaruukki has been responsible for funding the research, which is also included in the Osiris project of the European Union since December 1996. The project was to develop a laser measurement system for the raceway combustion phenomena, and also a numerical model for the raceway simulations. The other members of the project were some manufacturing companies, and also Cham Ltd. from U.K. Cham Ltd. has developed the CFD code Phoenics, which has also been used by the authors in the research.

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

1998-07-01

35

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...

36

Desirable blast velocity from the view point of fine coke deposit around blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

The blast velocity at a tuyere was investigated through the cold experiment utilizing a two-dimensional model of the lower part of the blast furnace, and the coke combustion experiment in a raceway furnace. When the raceway penetration (Dr), a converted value for the practical blast furnace, is increased above 1.3 m by enhancing the blast velocity at the tuyere or the pig-iron delivery ratio, the powdering amount of the coke in the raceway and the amount of the fine coke deposit on the core surface are increased. As the result, the extension of the furnace core causes a reduction in the fine-coke descending region, and also an increase in the descending rate of the charges near the furnace wall, resulting in a reduction in the temperature of the furnace core and the furnace wall. From the derived equation of Dr, it is estimated that the Dr in most of the large scale blast furnaces is about 1.4 m. However, it is needed that Dr is reduced by 10 cm and over for the above-mentioned reasons. From the calculation formula of the blast velocity at the tuyere (Ut), the 10 cm reduction in the Dr requires about 30 m/sec. in the Ut. Reduction in the Ut. can inhibit the powdering of the coke. (8 figs, 2 tabs, 2 refs)

Tamura, Kenji; Ichida, Morimasa; Wakimoto, Hirofumi; Ono, Katsuya; Hayashi, Yoichi

1987-11-01

37

Process control of mini blast furnaces; Controle de processo de mini altos-fornos  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model for charcoal blast furnaces is described. This mathematical model requires low investment in sensors and is an essential tool for a stable operation of charcoal blast furnaces. (author)

Castro, Luiz Fernando Andrade de; Tavares, Roberto Parreiras [Minas Gerais Univ., Belo Horizonte, MG (Brazil)]. E-mail: lfac@demet.ufmg.br; rtavares@demet.ufmg.br

2002-11-01

38

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

39

Development trends of fuel demand in blast furnace processes  

Energy Technology Data Exchange (ETDEWEB)

Analyzes consumption of coke in blast furnaces in Czechoslovakia in the 1980s. From 1975 to 1982 the consumption rate of coke in relation to iron was increasing; from 1982 to 1989 it declined due to improved technologies. The difference between minimum coke consumption rates and actual rates is defined as a blast furnace reserve. This difference, reflecting the excessive coke consumption in Czechoslovakia, was high and exceeded the level characteristic of developed countries. Use of mathematical modeling of processes that occur in a blast furnace to reduce coke consumption rates is discussed. Types of conventional mathematical models and models developed recently in Czechoslovakia are comparatively evaluated. Reactivity of coke from Czechoslovakia is considered. Advantages of the advanced mathematical models are analyzed.

Kret, J.; Bilik, J. (Wyzsza Szkola Gornicza, Ostrava (Czech Republic))

1992-11-01

40

Blast-furnace coke: a coal-blending model  

Energy Technology Data Exchange (ETDEWEB)

The relationships between coal properties, the strength of coke, and the performance of a blast furnace were investigated by means of correlation studies, and a linear programming model was developed for the prediction of a coal blend based on these relationships. The unique feature of this approach is that it utilizes a knowledge of the minimum blast-furnace coke requirements, rather than the maximum attainable coke quality. The model predicts the least expensive coal blend that would still comply with the minimum coke-quality requirements of a blast furnace. The study also confirms the existence of a relationship between the rank and caking parameters of coal, and the hot strength of coke. The effect of coke-oven operating parameters on coke quality is also discussed. 14 refs., 10 figs., 1 tab., 3 apps.

Niekerk, W.H. van; Dippenaar, R.J. (Iscor Ltd., Pretoria (South Africa))

1991-02-01

 
 
 
 
41

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

42

Optimization of an Automatic Blast Furnace through Integrated Simulation Modeling  

Directory of Open Access Journals (Sweden)

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.

Ali Azadeh

2006-01-01

43

An overview of blast furnace A performance at ArcelorMittal Monlevade, Brazil  

Energy Technology Data Exchange (ETDEWEB)

The first blast furnace at Monlevade Works, based on charcoal, started up in 1937. Since then the route blast furnace-oxygen steelmaking has been used. In the course of the time, Monlevade Works ironmaking area went past some changes until reaching the present situation: one sinter plant and one blast furnace based on coke. This blast furnace started up in December 1999 and its nominal capacity is 1,040,000 thm/year. This paper aims at showing the evolution of blast furnace operational performance, within a seven year operation which allowed a production of 1,103,935 thm in 2006.

W.O. Borges; R.J. Santos; F.C. Andrade; T.O. Iglesias; A.E. Almeida; H.L. Brito; A.A. Rodrigues

2008-01-15

44

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 ...

45

The Change in Surface Area Properties of Blast Furnace  

Directory of Open Access Journals (Sweden)

Full Text Available Blast furnace sludge-BFS is a by-product and waste material of the iron and steel industry. Recently, the adsorption capabilities of blast furnace sludge have been attracting great interest. It is known that materials with modified surface properties can be obtained by different chemical and thermal treatments.The aim of this work was to investigate the influence of chemical treatment by acetic acid and thermal treatment by heating at 700 °C, on the surface properties of blast furnace sludge. Chemical treatment was performed by acetic acid adsorption on BFS.Microscopic observation was conducted using scanning electron microscopy (SEM method. Changes in examined surface area properties were analyzed by Brunauer-Emmett-Teller (BET and Barrett-Joyner-Halenda (BJH methods.Increasing of specific surface area, decreasing of pore size and better pore size distribution in BFS samples were registered after the applied experimental procedure. The obtained results revealed that the performed chemical and heat treatment presented the activation of blast furnace sludge.

Ra?enovi?, A.

2009-04-01

46

Studying and improving blast furnace cast iron quality  

Directory of Open Access Journals (Sweden)

Full Text Available 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 %.

?. ?. Balgabekov

2014-10-01

47

A static approach towards coke collapse modelling in blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Burden distribution control in a blast furnace has a close relationship with wind acceptance and gas utilisation. Quantification of radial distribution of ore and coke is important for proper control of blast furnace operation. Charging of metallic burden over a layer of coke causes a portion of the coke layer to get dislodged from its original position, similar to the situation observed when a heavy material is dropped on a bed of lighter particles. This phenomenon, designated 'coke collapse', significantly changes the ore/coke distribution in the radial direction and thus affects the permeability of the furnace shaft. In the present work a mathematical model for quantifying the amount of coke collapse has been proposed on the basis of 'stability of slope theory'. The calculation from this model has been compared with the results from experiments in simplified physical models. Predictions of the mathematical model are in good agreement with experimental results.

Nag, S.; Basu, S. Yu, A.B.

2009-10-15

48

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)

49

Optimisation of blast furnace raceway at high injection rates  

Energy Technology Data Exchange (ETDEWEB)

The aim of this project was to clarify the raceway behaviour during high coal injection operations and to establish its influence on the whole blast furnace operation. A two-dimensional physical model (coke combustion with cold air) was built to simulate the raceway dynamics. Results show an unsteady raceway, expanding cyclically from a minimal to a maximal size, followed by the massive collapsing of the coke vault. Without coal injection, most relevant parameters on the raceway size are coke grain size and gas flow rate, with opposite effects. Coal injection produces a quick change of the raceway behaviour, which becomes larger. Optical methods were developed to investigate raceway depth (peephole method) and three-dimensional raceway space (lance method) during blast furnace operation. Results show raceway dimensions of 40-110 cm in depth and 40-60 cm in width, with possible change of 30 cm in depth during short periods. These measurements could not be clearly correlated with the blast parameters and with the results of coke core borings performed in parallel at the tuyere level. The influence of many parameters (raceway, bird nest and dead man characteristics, burden distribution) on blast furnace operation has been studied with an upgraded mathematical model. Results contribute to get a better picture of the situation inside the blast furnace, mainly in terms of cohesive zone position and shape. They provide a better understanding of the involved phenomena, of their interactions and of the furnace behaviour in response to an increase of the coal injection rate. 108 figs., 22 tabs.

Lectard, E.; Danloy, G.; Blacknik, W.; Muelheims, K. [Arcelor, Maizieres-les-Metz (France)

2005-07-01

50

Laser radar systems in the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Three systems using laser radar techniques are described: optical stockrod Opstock, burden profiler and raceway sensor. An outline of these systems is given in addition to results from their operation on a BHP Steel Group furnace. In particular, recent results using the raceway sensor on a pulverized coal injection (PCI) furnace are described together with a discussion on the potential use of the sensor to investigate combustion in the raceway region.

Paton, A.T.; Wall, P.C. (BHP Research, Shortland (Australia)); Hughes, M. (BHP Steel, Newcastle (Australia). Rod and Bar Products Division)

1993-01-01

51

Three-dimensional modelling of in-furnace coal/coke combustion in a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

A three-dimensional mathematical model of the combustion of pulverized coal and coke is developed. The model is applied to the region of lance-blowpipe-tuyere-raceway-coke bed to simulate in-furnace phenomena of pulverized coal injection in an ironmaking blast furnace. The model integrates not only pulverized coal combustion model in the blowpipe-tuyere-raceway-coke bed but also coke combustion model in the coke bed. The model is validated against the measurements under different conditions. The comprehensive in-furnace phenomena are investigated in the raceway and coke bed, in terms of flow, temperature, gas composition, and coal burning characteristics. The underlying mechanisms for the in-furnace phenomena are also analysed. The simulation results indicate that it is important to include recirculation region in the raceway and the coke bed reactions for better understanding in-furnace phenomena. The model provides a cost-effective tool for understanding and optimizing the in-furnace flow-thermo-chemical characteristics of the PCI operation in full-scale blast furnaces. 32 refs., 10 figs., 3 tabs.

Y.S. Shen; B.Y. Guo; A.B. Yu; P.R. Austin; P. Zulli [University of New South Wales, Sydney, NSW (Australia). Lab for Simulation and Modelling of Particulate Systems

2011-02-15

52

A 3D CFD simulation of liquid flow in an ironmaking blast furnace  

Science.gov (United States)

A three-dimensional CFX-based mathematical model is developed to describe the flow-heat transfer-chemical reactions behaviours of gas-solid-liquid phases in an ironmaking blast furnace (BF), where the raceway cavity is considered explicitly. The typical in-furnace phenomena of an operating blast furnace, in particular, the liquid flow in the lower part of a blast furnace is simulated in aspects of velocity and volume fraction. This model offers a cost-effective tool to understand and optimize blast furnace operation.

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

2013-07-01

53

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

Science.gov (United States)

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.

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

2014-05-01

54

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

Science.gov (United States)

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

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

2012-05-01

55

Numerical simulation characteristics of unburned pulverised coal in blast furnace  

Energy Technology Data Exchange (ETDEWEB)

With increasing rates of pulverised coal injection into blast furnaces, it is important to understand the flow characteristics of unburned coal. Under some operating conditions, the coal powder can be stagnant in certain regions of the furnace and its permeability deteriorates. Thus a model studying the behaviour of unburned coal was produced. In the model, the coal burning in the raceway is affected by oxygen content and temperature of the gas. The simulation results demonstrate that the accumulation region of unburned coal is in the lower part of the inverse cohesive zone, above and under the tuyeres, and in the hearth centre.

Yu, Y.W.; Bai, C.G.; Liang, D.; Wang, F. [Chongqing University, Chongqing (China)

2009-05-15

56

Three-dimensional modelling of coal combustion in blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Pulverized coal injection technology is widely used in blast furnace ironmaking due to economic, operational and environmental benefits. High burnout within the tuyere and raceway is required for high coal injection rate operation. In order to analyze the flow and combustion in the tuyere and raceway more accurately and reliably, a three-dimensional model of coal combustion is developed. This model is validated against the measurements from two pilot scale test rigs in terms of gas species composition and coal burnout. The gas-solid flow and coal combustion are simulated and analysed. The results indicate that compared to our previous model, the present model is able to provide more detailed gas species distributions and better describe the evolutions of coal particles. It is more sensitive to various parameters and hence more robust in examining various blast furnace operations.

Shen, Y.S.; Guo, B.Y.; Yu, A.B.; Maldonado, D.; Austin, P.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia)

2008-07-01

57

Modelling the combustion of charcoal in a model blast furnace  

Science.gov (United States)

The pulverized charcoal (PCH) combustion in ironmaking blast furnaces is abstracting remarkable attention due to various benefits such as lowering CO2 emission. In this study, a three-dimensional CFD model is used to simulate the flow and thermo-chemical behaviours in this process. The model is validated against the experimental results from a pilot-scale combustion test rig for a range of conditions. The typical flow and thermo-chemical phenomena is simulated. The effect of charcoal type, i.e. VM content is examined, showing that the burnout increases with VM content in a linear relationship. This model provides an effective way for designing and optimizing PCH operation in blast furnace practice.

Shen, Yansong; Shiozawa, Tomo; Yu, Aibing; Austin, Peter

2013-07-01

58

Evaluation Of Concrete Properties Using Ground Granulated Blast Furnace Slag  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Traditionally, Ordinary Portland Cement concrete is used for making the civil structures. Portland cement can be replaced by Ground Granulated Blast Furnace Slag (GGBFS) which is a non-metallic and non-hazardous waste of the Iron industry. It is suitable for concrete mix and improves properties of concrete like compressive strength, workability etc. It has been seen that when cement is replaced with GGBFS compressive strength increases. However, this increase in compressive strength continues...

Pathan, Veena G.; Ghutke, Vishal S.; MR. GULFAM PATHAN

2013-01-01

59

Soil Stabilisation Using Ground Granulated Blast Furnace Slag  

Directory of Open Access Journals (Sweden)

Full Text Available Stabilisation is a broad sense for the various methods employed and modifying the properties of a soil to improve its engineering performance and used for a variety of engineering works. In today?s day soil stabilisation is the major problem for civil engineers, either for construction of road and also for increasing the strength or stability of soil and reduces the construction cost. In this thesis the soil are stabilised by ground granulated blast furnace slag (GGBS and this material is obtained from the blast furnace of cement plant, which is the byproduct of iron (from ACC plant, sindri. It is generally obtained in three shaped one is air cooled, foamed shaped and another is in granulated shaped. The use of by-product materials for stabilisation has environmental and economic benefits. Ground granulated blast furnace slag (GGBS material is used in the current work to stabilise soil (clay. The main objectives of this research were to investigate the effect of GGBS on the engineering property (optimum moisture content and maximum dry density, plastic limit, liquid limit, compaction, unconfined compressive strength, triaxial and California bearing ratio test of the soil and determine the engineering properties of the stabilised.

Ashish Kumar Pathak

2014-05-01

60

Raceway behaviors in blast furnace with pulverized coal injection  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace raceway shows different characteristics with PCR (pulverized coal injection rate). It was found in this study that with the increase of PCR the raceway depth decreases, and the size of birds nest and sometimes with liquid holdup, increases. Oxygen enrichment with co-axial lances was known to be very effective on the extension of raceway depth and size reduction of birds nest. It was also found that there are various factors which affect the coke properties at tuyere level of the blast furnace. Coke traveling time was calculated to be extended with PCR and it had a close relationship with the coke size in bosh. Coke mean size decreased with the increase of coke traveling time, that is, with the increase of PCR. Both DI (the strength of coke in cold) and CSR (the strength of coke after reaction) were also decreased with PCR. RAFT (Raceway Adiabatic Flame Temperature) had a tendency to be decreased with the increase of PCR, which is obtained by the estimation of coke temperature via XRD analysis. From the analysis of alkali contents in coke sampled along the radius of the blast furnace, it was understood that no difference in alkali contents between fine and lump coke represents that coke fines generated from upper burden might appear at tuyere level.

Chung, J.K.; Han, J.W.; Cho, B.R. [POSCO, Cheollanamdo (Korea, Republic of)

1995-12-01

 
 
 
 
61

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

Directory of Open Access Journals (Sweden)

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.

J. Terpák

2010-04-01

62

First international coking congress, Essen 1987 - section C: coke quality and coke behavior in blast furnaces  

Energy Technology Data Exchange (ETDEWEB)

Summarizes 7 papers presented at section C of the conference, dealing with: experiments conducted in Japan using samples taken from a blast furnace charge to investigate mechanism by which coke is formed in lower part of furnace; experiments conducted in France to establish granulometric, chemical and textural properties of coke in furnace; coke quality as evidenced by operational results using 3,000 m{sup 3} blast furnace at Port Kemble, Australia; effect of alkalis on coke quality indicators as revealed by laboratory experiments: chemical and physical effect of alkalis on blast furnaces; limiting effect of high sulfur content on blast furnace operation by adding lime to coal mixture; effect of titanium in charge on blast furnace coke. 7 refs.

Lukes, V.

1989-05-01

63

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

Directory of Open Access Journals (Sweden)

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.

A. Konstanciak

2013-04-01

64

Modelling of turbulent combustion in the blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-12-31

65

Combustibility of coal-water slurry in a blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

Investigations are reported of the combustibility of high-concentration coal-water slurry injected into a test furnace and into an actual blast furnace. The goal of this research is the application of such slurries to blast furnace fuel injection. Various slurry combustion characteristics have been clarified, including ignition lag due to evaporation of the moisture content, and combustion efficiency. In addition, the test furnace was used to evaluate the effect of a number of combustion-promoting measures. 1 reference.

Inagaki, N.; Otabe, T.; Kawaoka, K.; Asai, K.; Ishimatsu, H.; Wakimoto, H.

1985-01-01

66

Numerical predictions on the influences of the air blast velocity, initial bed porosity and bed height on the shape and size of raceway zone in a blast furnace  

International Nuclear Information System (INIS)

A numerical model has been developed to predict the shape and size of the raceway zone (a void space) created by the force of the blast air injected through the tuyeres in the packed coke bed of a blast furnace. The model is based on the solution of conservation equations of both gas and solid phases as interpenetrating continua on a Eulerian-Eulerian frame. A modified k-? model has been adopted for gas phase turbulence. The solid phase constitutive equation is characterized by the solid pressure, bulk viscosity and shear viscosity, which are evaluated from the kinetic theory of random motions of granular materials in a fluid flow. The influences of the air blast velocity, initial porosity of the coke bed and the bed height on the shape and size of the raceway zone have been predicted

67

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

Energy Technology Data Exchange (ETDEWEB)

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.

Dr. Chenn Zhou

2012-08-15

68

Recent blast furnace operation; Saikin no yokoro sogyo ni tsuite  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces efforts and works intended to increase production from a blast furnace which executes simultaneous smelting of zinc and lead. Because the raw zinc production amount is proportional to tuyere air volume, hearth renewal and hearth expansion were carried out aiming at increasing the air volume. Difference in operation before and after the expansion was compared and the following results were obtained: air blow resistance in the furnace decreased by about 2500 Pa according to actual measurement, resulting in suppressing increase of impure copper in the raw zinc in association with increase in the air volume; enhancement has been expected in ZnO reducing reaction efficiency as a result of reduction in gas rising velocity, but no improvement was recognized; and the expansion achieved a tuyere air volume of 36230 Nm {sup 3} per hour, which corresponds to monthly production increase of vaporized zinc at 400 tons. Discussions were given for conversion to two kinds of cokes including imported cokes for general blast furnace use. The conversion would be possible by using the cokes under severer conditions than those for conventional cokes, by increasing coke charging amount, and by improving coke powdering rate. As a result of discussing Pb treatment methods that can meet the new waste water criteria, it was found that repetitive co-precipitation reaction under the presence of a co-precipitation agent is advantageous technologically and economically. 8 refs., 15 figs., 3 tabs.

Kakutani, H.; Tachida, N.; Kudo, M. [Sumitomo Metal Mining Co. Ltd., Tokyo (Japan)

1997-06-25

69

Injection of heavy fuel oil into the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

1996-12-31

70

Acid slag injection into the blast furnace tuyere zone  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-12-31

71

New technologies in blast furnace burden distribution - physical modelling  

Energy Technology Data Exchange (ETDEWEB)

Experimental work carried out on a full scale physical model of Port Kembla's No. 5 blast furnace bell-less top is described. Measurements of surface profiles, particle size segregation, material trajectory and the coke collapse phenomenon were obtained. Experimental techniques developed for the trials included the use of photogrammetry for profile determination and novel methods of sampling material from burden layers. An analysis of the information has made it possible to determine appropriate practice specific data for the application of a burden distribution model. 8 refs., 9 figs.

Zulli, P.; Tanzil, W.B.U.; Monaghan, J.; McCarthy, M.J.; Hockings, K.L. (BHP Central Research Laboratories, Port Kembla, NSW (Australia). Slab and Plate Products Division)

1988-01-01

72

Thermal deactivation of chars under blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

Chars with low reactivities to oxygen can be prepared using high temperature wire mesh reactor (HTWM); the chars can have reactivities similar to metallurgical cokes (metcokes). High resolution transmission electron microscopy (HRTEM) studies have shown that very high levels of thermally-induced ordering can occur in residual coal chars. Structural changes are accompanied by significant reductions in reactivity for oxidation and gasification. As thermal deactivation varies between coals, char preparation under representative conditions will allow selection of coals which exhibit higher reactivity under actual blast furnace conditions. 9 refs., 3 figs.

Man, C.K.; Russell, N.V.; Gibbins, J.R.; Williamson, J. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Department of Mechanical Engineering

1999-07-01

73

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)

74

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...

75

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...

76

Alkali-activated blast furnace slag-zeolite cements and concretes  

International Nuclear Information System (INIS)

trength 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

77

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

78

Nodal wear model: corrosion in carbon blast furnace hearths  

Directory of Open Access Journals (Sweden)

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.

Verdeja, L. F.

2003-06-01

79

Preparation of Ceramic-Bonded Carbon Block for Blast Furnace  

Science.gov (United States)

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.

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

2014-01-01

80

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.)

 
 
 
 
81

Recycling of plastic waste in blast furnace; Koro ni okeru hai plastic riyo gijutsu  

Energy Technology Data Exchange (ETDEWEB)

Features particular to the technology of using a blast furnace for the recycling of plastic waste are reported, and the behavior of plastic waste injected into a blast furnace is described. The plastic waste is injected into the furnace borne on a 1200degC hot blast through the tuyere. The plastic is converted into a reducing gas in the furnace, and the gas on its way up in the furnace is utilized as a reducing agent in the iron ore reducing reaction. The process is described below. All kinds of plastic waste may be utilized in this fashion, with the exception of polyvinyl chloride. As for polyvinyl chloride, efforts are under way to develop a technology to recycle this plastic. The method using the blast furnace tolerates a wide range of impurities, and the plastic waste is only to be crushed and granulated before use in the furnace. Plastic waste coarsely granulated but not pulverized may be completely gasified when the blast furnace raceway function is utilized. Since plastic waste in a blast furnace may be used as an iron ore reducing agent, it enjoys a high recyclability rate. Plastic waste produces less CO2 than coal does. 7 refs., 15 figs.

Asanuma, M.; Ariyama, T.; Yamada, Y.; Fujii, M.; Okochi, I.; Sumigama, T. [NKK Corp., Tokyo (Japan); Tokuda, M. [Tohoku University, Sendai (Japan). Center for Interdisciplinary Research

1998-05-20

82

The development of technology for the injection of pulverized coal into a blast furnace (II): the effect of pulverized coal injection on blast furnace raceway phenomena  

Energy Technology Data Exchange (ETDEWEB)

A vertical combustion furnace was used to study the effects of pulverized coal injection on various raceway phenomena, the aim being to develop technology for the injection of pulverized coal into a blast furnace. The effects on gas and temperature distributions in the raceway, and on raceway depth and gas permeability, were clarified. A diagram is given of the combustion furnace used in the experiments and the experimental results are indicated (1 ref.) (In Japanese)

Kanayama, H.; Seki, Y.; Saito, T.; Maekawa, M.; Narita, K.; Tamura, S.

1982-01-01

83

Laser sensing in the iron-making blast furnace  

Science.gov (United States)

The measurement of parameters such as distance and temperature in the Ironmaking Blast Furnace is crucial to the performance of the furnace. A series of instruments has been designed, built and tested by BHP which perform these tasks optically requiring no physical intrusion into the harsh environment of the furnace. The problem of coupling high peak power Nd:YAG and ultra violet laser radiation into environments consisting of very high water vapour level, acidic, high aerosol loading, and high temperature environments is considered. The performance of two systems enabling distance measurement with sub-pulse length range resolution under the above conditions is discussed in detail. The use of optical fibres to deliver the pulsed energy to and from the environment together with specific window design parameters are also described. A major problem in making time of flight range measurements in very high density aerosol conditions is the signal processing required to extract the target return pulse position from the complex aerosol return signal. Incoherent detection techniques used to achieve this discrimination where target temperatures can exceed 2000°C are discussed. The selection of operating laser wavelength and repetition rate were based on an analysis of the optical characteristics of gases and aerosol forming the measurement environment together with the dynamic behaviour of the high temperature target. The extension of laser radar techniques to optical fibres is discussed and a distributed temperature sensing system is described which measures temperatures up to 250°C with a spatial resolution better than O.Sm.

Scott, J. Chris

1991-03-01

84

Modeling of Blast Furnace with Layered Cohesive Zone  

Science.gov (United States)

An ironmaking blast furnace (BF) is a moving bed reactor involving counter-, co-, and cross-current flows of gas, powder, liquids, and solids, coupled with heat exchange and chemical reactions. The behavior of multiple phases directly affects the stability and productivity of the furnace. In the present study, a mathematical model is proposed to describe the behavior of fluid flow, heat and mass transfer, as well as chemical reactions in a BF, in which gas, solid, and liquid phases affect each other through interaction forces, and their flows are competing for the space available. Process variables that characterize the internal furnace state, such as reduction degree, reducing gas and burden concentrations, as well as gas and condensed phase temperatures, have been described quantitatively. In particular, different treatments of the cohesive zone (CZ), i.e., layered, isotropic, and anisotropic nonlayered, are discussed, and their influence on simulation results is compared. The results show that predicted fluid flow and thermochemical phenomena within and around the CZ and in the lower part of the BF are different for different treatments. The layered CZ treatment corresponds to the layered charging of burden and naturally can predict the CZ as a gas distributor and liquid generator.

Dong, X. F.; Yu, A. B.; Chew, S. J.; Zulli, P.

2010-04-01

85

Iron ores, fluxes and tuyere injected coals used in the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Iron ores, fluxes and tuyere injected coals used as burden materials in the blast furnace have been characterised by chemical and granulometric analysis, moisture, density and porosity, softening and melting temperatures, reductibility, X-ray diffraction, electronic microscopy and thermoanalysis. Theoretical calculations on the influence of both the chemical composition and ash content of coals on some aspects of the blast furnace operation have been carried out. The combustion behaviour of pulverised coals in a pilot plant equipped with a combustion chamber has been studied to indicate what the behaviour of each type of coal will be, when injected in blast furnace tuyeres.

Cores, A.; Babich, A.; Muniz, M.; Isidro, A.; Ferreira, S.; Martin, R. [CSIC, Madrid (Spain)

2007-05-15

86

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

MAHSHAD YAZDANIPOUR; EBRAHIM NAJAFI KANI; ALI ALLAHVERDI

2011-01-01

87

Evaluation Of Concrete Properties Using Ground Granulated Blast Furnace Slag  

Directory of Open Access Journals (Sweden)

Full Text Available Traditionally, Ordinary Portland Cement concrete is used for making the civil structures. Portland cement can be replaced by Ground Granulated Blast Furnace Slag (GGBFS which is a non-metallic and non-hazardous waste of the Iron industry. It is suitable for concrete mix and improves properties of concrete like compressive strength, workability etc. It has been seen that when cement is replaced with GGBFS compressive strength increases. However, this increase in compressive strength continues up to a certain percentage of replacement, but higher ratios gives lower compressive strength. The main objective of this research work is to determine the optimum replacement percentage which can be suitably used under the Indian conditions. To fulfil the objective various properties of concrete using GGBFS have been evaluated.

MRS. VEENA G.PATHAN

2013-01-01

88

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

89

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)

90

Enriching blast furnace gas by removing carbon dioxide.  

Science.gov (United States)

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

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

2013-12-01

91

Waste Heat Recovery from Blast Furnace Slag by Chemical Reactions  

Science.gov (United States)

Blast furnace (BF) slag, which is the main byproduct in the ironmaking process, contains large amounts of sensible heat. To recover the heat, a new waste heat-recovery system—granulating molten BF slag by rotary multinozzles cup atomizer and pyrolyzing printed circuited board with obtained hot BF slag particle—was proposed in this study. The feasibility of the waste heat-recovery system was verified by dry granulation and pyrolyzation experiments. The energy of hot BF slag could be converted to chemical energy through the pyrolysis reaction, and a large amount of combustible gas like CO, H2, C m H n , and CH4 can be generated during the process.

Qin, Yuelin; Lv, Xuewei; Bai, Chenguang; Qiu, Guibao; Chen, Pan

2012-08-01

92

Blast furnace slag use reduces well completion cost  

Energy Technology Data Exchange (ETDEWEB)

In an effort to reduce South Texas Stratton-field remedial-squeeze operations, Union Pacific Resources Co. (UPRC), in conjunction with The Western Co. of North America and Zarsky Oilfield Services, applied unique and emerging technology to its mud systems and cementing practices. Quick Quenched Blast Furnace Slag (BFS) was added to the drilling fluid (producing universal fluid) and to cement slurries to improve annular isolation, thus reducing and/or eliminating need for remedial squeeze work. By improving primary cement jobs, UPRC reduced remedial operations by 100% and overall well cost y an average $80,000 per well. This article discusses the following topics involved in BFS mud-system and cementing applications: Stratton field background including completion practices and main operational field problems; drilling fluid field characteristics; field cementing procedures and problems; universal fluid/BFS cement applications including compressive strength and annular isolation; field application case histories, and discussion of results.

McCarthy, S.M.; Daulton, D.J. [Western Co. of North America, Dallas, TX (United States); Bosworth, S.J. [Union Pacific Resources Co., Fort Worth, TX (United States)

1995-04-01

93

Blast furnace slags as sorbents of phosphate from water solutions.  

Science.gov (United States)

The paper is focused on the sorption of phosphorus from aqueous solutions by crystalline and amorphous blast furnace slags. Slag sorption kinetics were measured, adsorption tests were carried out and the effect of acidification on the sorption properties of slags was studied. The kinetic measurements confirmed that the sorption of phosphorus on crystalline as well as amorphous slags can be described by a model involving pseudo-second-order reactions. For all slag types, phosphorus sorption follows the Langmuir adsorption isotherm. The acid neutralizing capacities of crystalline and amorphous slags were determined. In the case of the crystalline slags, buffering intervals were found to exist during which the slag minerals dissolve in the sequence bredigite-gehlenite-diaspor. There is a high correlation (R2=0.9989) between ANC3.8 and the saturation capacities of crystalline and amorphous slags. PMID:15899277

Kostura, Bruno; Kulveitová, Hana; Lesko, Juraj

2005-05-01

94

Hydrothermal solidification of blast furnace slag by formation of tobermorite  

Energy Technology Data Exchange (ETDEWEB)

Abstract: Blast furnace water-cooled slag (BFWS) has been solidified using a hydrothermal processing method, in which the BFWS could be solidified in an autoclave under saturated steam pressure (1.56 MPa) at 200 {sup o}C for 12 h by the additions of quartz or coal flyash. The tensile strength development was shown to depend on the formation of tobermorite and the packing state of the formed tobermorite in the solidified bodies. The additions of quartz or fly ash were proved to be favorable not only to the formation of tobermorite but also to the transformation of hibschite, the former improving the strength, and the latter deteriorating the strength. The excessive addition of quartz appeared to cause strength deterioration due to the fact that the residual quartz affected the formation of tobermorite in the solidified bodies.

Jing, Z.; Jin, F.; Hashida, T.; Yamasaki, N.; Ishida, H. [Tohoku University, Miyagi (Japan). Graduate School of Environmental Studies

2007-10-15

95

Determination of coal combustion under simulated blast furnace raceway conditions. Final report  

Energy Technology Data Exchange (ETDEWEB)

The aim of this project is to determine the coal injection rate at which, due to incomplete combustion, the amount of residual products is so high that they are likely to cause operational problems. The coal was burned inside the raceway or the surrounding coke bed. The permability of the blast furnace decreases due to residuals of incomplete combustion blown into the blast furnace and this sets a limit to coal injection. To investigate this, the raceway and part of the surrounding coke column were simulated at a laboratory scale. The parameters investigated were the coal rate, oxygen content of the blast, coal type, particle size and blast temperature.

Steeghs, A.G.S. [Hoogovens, Ijmuiden (Netherlands)

1995-11-01

96

Comparison of possibilities the blast furnace and cupola slag utilization by concrete production  

Directory of Open Access Journals (Sweden)

Full Text Available In process of pig iron and cast iron production secondary raw materials and industrial wastes are formed The most abundant secondaryproduct originating in these processes are furnace slag. Blast furnace slag and cupola furnace slag originates from melting of gangue parts of metal bearing materials, slag forming additions and coke ash. In general, slag are compounds of oxides of metallic and non-metallic elements, which form chemical compounds and solutions with each other and also contain small volume of metals, sulfides of metals and gases. Chemical, mineralogical and physical properties of slag determinate their utilisation in different fields of industry.The paper presents results from the research of the blast furnace and cupola furnace slag utilization in the concrete production. Pilotexperiments of the concrete production were performed, by that the blast furnace and cupola furnace slag with a fractions of 0–4mm;4–8mm; 8–16mm were used as a natural substitute. A cupola furnace slag and combination of the blast furnace and cupola furnace slagwere used in the experiments. The analysis results show that such concretes are suitable for less demanding applications.

D. Baricová

2010-04-01

97

Quality criteria for blast-furnace injection coals  

Energy Technology Data Exchange (ETDEWEB)

This paper reviewed the history of coal injection at United States Steel Corporation. Currently, pulverized coal (PC) is injected on 10 blast furnaces at the company's facilities at 5 different plants in the United States, Canada and Slovakia. Although low-volatile bituminous coal was used extensively at several sites in the past, all the furnaces now inject high-volatile bituminous coal. The choice of coal injection depends on cost, physical and chemical properties an intended application. Any type of coal can be used for low injection levels. As injection rates increase however, the choice of coal or coal blends depend on more complex characteristics such as combustibility, char reactivity and flow characteristics. Although low-volatile, higher rank bituminous coals usually provide higher coke replacement ratios, they can be more difficult to convey and burn. In contrast, high-volatile, lower rank coals are typically more reactive and easier to convey, but offer lower coke replacement ratios and could even contribute to furnace instability. This paper presented lessons learned with various types of injection coal. It also reviewed existing and emerging standards for choosing injection coals. The parameters that must be considered when choosing from a set of coals include moisture and hardness; carbon and hydrogen content; oxygen content; impurities; coal value; coal rank; conveying properties; reactivity; and coal type and injection rate. Coals with less ash, sulphur and alkali are usually preferred. For ironmaking, coals ranging in rank from anthracite to high-volatile bituminous coal are suitable for low to moderate injection rates. 14 refs., 7 figs.

Lherbier, L.W.Jr.; Serrano, E.J. [United States Steel Corp., Munhall, PA (United States). Research and Technology Center

2008-07-01

98

Simulation study on radiative imaging of pulverised coal combustion in blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

Radiative imaging of pulverised coal combustion in the blast furnace raceway plays an increasingly important role in working state diagnosis and monitoring in real time. This paper presents a new method for calculating the radiation of three-dimensional (3D) combustion flames based on the Monte Carlo method and charge coupled device (CCD) imaging. The relationship between two-dimensional radiative image and 3D radiant energy in the blast furnace raceway was studied by numerical simulation of the combustion process in this study. The radiative images obtained from the blow pipe peephole of a blast furnace tuyere not only present the energy distribution on the CCD camera target plane but also examine 3D temperature distribution in the blast furnace. The numeral temperature field matching the actual combustion can be obtained by a proposed numeric image processing technique.

Ouyang, Q.; Zhao, L.M.; Wen, L.Y.; Bai, C.G. [Chongqing University, Chongqing (China)

2011-04-15

99

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...

100

The challenges of coal injection in today's blast furnaces  

Energy Technology Data Exchange (ETDEWEB)

The fourteen papers (including the keynote address) addressed various aspects of pulverised coal injection in blast furnaces, including coal quality criteria, ramping up PCI production and tuyere development. The discussion of the papers is also included.

Irons, G.A. (ed.) [McMaster University, Hamilton, ON (Canada). Steel Research Centre

2009-07-01

 
 
 
 
101

High-speed television system for blast furnace raceway coke measurements  

Energy Technology Data Exchange (ETDEWEB)

This article describes a system using a television camera fitted with a high-speed shutter for measuring coke behaviour and particle size in raceways associated with blast furnace tuyeres. (2 refs.) (In Japanese)

Watanabe, K.

1981-01-01

102

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1982-04-30

103

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

104

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

105

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

Directory of Open Access Journals (Sweden)

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.

Malind?ák Du?an

1996-12-01

106

Latest Evolution in Blast Furnace Hearth thermo-Mechanical Stress Modelling  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Saint-Gobain has a long experience in the design and supply of blast furnace hearth linings. The Blast Furnace Hearth is arguably the most critical part within the whole integrated steel plant when considering overall potential profit/loss. Typical wear lines found in the BF hearth match closely with the areas subject to highest Thermo-Mechanical stresses. There is clear interest in being able to estimate the thermo-mechanical stresses experienced between different designs. Thanks to FEM tool...

Brulin, J.; Roulet, F.; Rekik, A.; Blond, Eric; Gasser, Alain; Mc Nally, Rory; Micollier, M.

2011-01-01

107

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)

108

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Carrasco, M. F.; Bonavetti, V. L.; Irassar, E. F.

2003-01-01

109

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Babich, A.; Senk, D.; Gudenau, H. W.; Mavrommatis, K.; Spaniol, O.; Babich, Y.; Formoso, A.

2005-01-01

110

Blast furnace operating conditions manipulation for reducing coke consumption and CO{sub 2} emission  

Energy Technology Data Exchange (ETDEWEB)

A comparative reduction behavior of wuestite samples prepared from iron ore sinter was investigated to find the optimum way for reducing coke consumption and CO{sub 2} emission in blast furnace technology. A series of wuestite reduction experiments was carried out using different gas mixtures. A correlation between the experimental results and real data of blast furnaces at Egyptian Iron and Steel Company (EISCO) was demonstrated in order to optimize the coke consumption inside blast furnaces. Different theoretical models were applied on real data of blast furnaces to calculate the effect of operation parameters on the coke consumption. It was found that the wuestite reducibility can be controlled and enhanced using certain ratio of H{sub 2} and CO gases. Such kind of enhancement decreases the remaining quantity of unreduced wuestite which descends to the high temperature region of blast furnace. The theoretical analysis of real data using certain values of H{sub 2} and CO shows that increasing the amount of natural gas injection in blast furnace of EISCO will decrease the degree of direct reduction of iron oxide and consequently will decrease the amount of coke consumption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Bahgat, Mohamed; Abdel Halim, Khaled S.; El-Kelesh, Heba Ali; Nasr, Mahmoud I. [Central Metallurgical Research and Development Institute (CMRDI), Cairo (Egypt)

2012-07-15

111

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

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

2004-01-01

112

Influence of blast-furnace process thermal parameters on energy and exergy characteristics and exergy losses  

Energy Technology Data Exchange (ETDEWEB)

The technology 'blast furnace-converter' currently dominates the production of steel all over the world. Therefore, the blast-furnace process is continuously being improved, among other ways, by raising the thermal parameters, such as temperature and oxygen-enrichment of the blast, as well as the addition of auxiliary fuels. The changes in the consumption of coke go together with changes in the consumption of blast, the production of top-gas and its consumption in Cowper stoves, as well as the production of electricity in the recovery turbogenerator utilizing the waste exergy of the top-gas due to raised pressure. Related to a unit of pig iron production, these values are called energy (exergy) characteristics of the blast-furnace plant. They serve as a quantity measure of the thermal improvement of the blast-furnace process. This paper presents an algorithm of the process exergy analysis of simulative investigations of the influence of increased thermal parameters on the thermodynamic perfection of the process and the blast-furnace plant. This algorithm is based on the theoretical empirical balance method of the input-output type. By means of this algorithm the influence of increased thermal parameters of the process not only on the saving of coke but also of the blast can be determined, as well as of the production and composition of top-gas, the consumption of top-gas in the Cowper stoves and the production of electric energy in the recovery turbine. The blast-furnace process displays a high exergy efficiency, whereas the process of compressing and preheating the blast is characterized by rather high exergy losses due to the application of the combustion process. It has been shown that the internal exergy losses in the blast furnace are comparable with the exergy losses in the processes of compressing and preheating of the blast. Calculations were carried out for a modern Polish blast furnace with a volume of 3200 m{sup 3}. 15 refs., 12 figs., 1 tab.

Andrzej Zibik; Wojciech Stanek [Silesian University of Technology, Gliwice (Poland). Institute of Thermal Technology

2006-03-25

113

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

114

Tuyere development as an effective measure for high PC rate operation of blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Kobe Steel has developed technologies to reduce coke consumption in its blast furnaces by injecting coal at a high rate. This paper described a newly developed tuyere and its contribution to improving permeability under high pulverized coal (PC) rate conditions at the blast furnaces at Kakogawa Works. Reducing the coke rate while increasing the coal injection rate results in higher ore/coke at the center region of the furnace, resulting in excessive peripheral gas and inducing gas channeling. Central coke charging (CCC) helps attain a stable gas flow inside the furnace by forming a vertical gas passage in the coke column. It enables furnace operators to directly control or enhance the central gas flow and improves gas and liquid permeability in the furnace bottom. In a conventional tuyere, the PC is introduced in or before the converged blast flow inside the tuyere where coal fines begin to decompose and interact with hot blasts. This newly developed convergent and divergent (CD) type tuyere was instrumental in safely reducing the pressure drop and its variation to a tolerable level even under ultra-high PCR conditions over 250 kg/thm. This paper described the effects of tuyere structure on raceway shapes using 3 types of tuyeres in a coke packed test furnace. It was concluded that the CD tuyere reduces pressure drop at the tuyere. An increase in PC rate offers benefits in terms of furnace stability. The CD tuyere also reduces coke deterioration in the raceway. 7 refs., 8 figs.

Tagawa, T.; Kasai, A.; Nozawa, K.; Shibata, K. [Kobe Steel Ltd., Kakogawa Works, Hyogo (Japan). Ironmaking Dept.

2008-07-01

115

Methods for monitoring heat flow intensity in the blast furnace wall  

Directory of Open Access Journals (Sweden)

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.

L'. Dor?ák

2010-04-01

116

[Study on quantificational analysis method for the non-crystalline content in blast furnace slag].  

Science.gov (United States)

Quantificational analysis method for the non-crystalline and crystalline contents in blast furnace slag was studied by means of X-ray diffraction. The process of quantificational analysis method includes standard samples preparation, samples preparation, X-ray diffraction measurement and data treatment. The data treatment includes integration areas of non-crystalline curve and crystalline peaks in certain diffraction angle range, linear fitting and quantificational coefficient determination. The preparation methods of standard samples for X-ray diffraction of blast furnace slag were proposed, including 100% crystalline sample and 100% non-crystalline sample. The 100% crystalline sample can be obtained by heating blast furnace slag for 12 h at 1 000-1 200 degrees C, and the 100% non-crystalline sample can be obtained by quenching the molten slag with enough water. The X-ray diffraction method of quantificational analysis of non-crystalline content in blast furnace slag was proposed with the 100% non-crystalline and 100% crystalline standard samples, and the quantificational coefficient can be obtained by linear regression on the integration areas of non-crystalline curve and crystalline peaks of X-ray diffraction in the 2-theta range 20 degrees-40 degrees. This method is suitable for the blast furnace slag with the non-crystalline content over 80%. The non-crystalline and crystalline contents of original blast furnace slag are obtained by combining the X-ray diffraction results and mathematical treatment, and this method is suitable for the blast furnace slag with the non-crystalline content over 90%, whose process includes preparing the 100% crystalline standard sample by heating blast furnace slag for 12 h at 1000-1200 degrees C, samples preparation with the 0.02 interval in the 0-0.1 mass ratio range of 100% crystalline to original slag, X-ray diffraction measurement of the samples prepared and data treatment using iterative linear regression. The quantificational analysis method for blast furnace slag can be applied to various kinds of blast furnace slag from different steel plants. PMID:18479048

Yan, Ding-Liu; Guo, Pei-Min; Qi, Yuan-Hong; Zhang, Chun-Xia; Wang, Hai-Feng; Dai, Xiao-Tian

2008-02-01

117

A Study of the Heat Flow in the Blast Furnace Hearth Lining  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of the present thesis was to study the heat flows in the blast furnace hearth lining by experimental measurements and numerical modeling. Thermocouple data from an operating furnace have been used throughout the work, to verify results and to develop methodologies to use the results in further studies. The hearth lining were divided into two zones based on the thermocouple readings: a region with regular temperature variations due to the tapping of the furnace, and another region with...

Swartling, Maria

2010-01-01

118

Results of measurement of blast furnace raceway coke by means of high-speed television  

Energy Technology Data Exchange (ETDEWEB)

As was previously reported a specially developed raceway coke measuring system has been used to make continuous measurements of the particle size of coke in front of the tuyeres of an operating blast furnace. Analysis of these measurements now confirms that raceway coke particle size and furnace gas permeability are related, and that changes in coke particle size in the furnace are dependent upon pre-charging properties and operating conditions. 1 reference.

Saitoh, H.; Sumigama, T.; Kamoshida, T.; Izumi, M.

1983-01-01

119

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)

120

Statistical methods for determining the influence of coke properties on performance of a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

The effects of coke mechanical properties on operation of blast furnaces are evaluated. The evaluations are based on statistical data on operation of blast furnaces in Poland from 1979 to 1980. Analyses show that coke compression strength and wear decisively influence yield of pig iron and coke consumption rates. This influence is more intensive in the case of blast furnaces with a capacity below 2000 m/sup 3/ than in the case of larger furnaces. Decrease in coke compression strength of 1% causes an increase in coke consumption rate ranging from 16 to 20 kg/t pig iron in blast furnaces with a capacity to 2000 m/sup 3/ iron, while in blast furnaces with a capacity larger than 2000 m/sup 3/, coke consumption rate increases 10%. There is a correlation between fluctuations of coke compression strength, coke wear and yield of pig iron. Increase in yield of pig iron is achieved by coke compression strength increase or by reducing coke wear. Increasing coke compression strength (the M40 index) by 1.0 causes the identical iron yield increase as by reducing coke wear by 0.1. Reducing coke consumption rates is achieved by increasing coke compression strength or reducing its wear. Increasing coke compression strength by 0.1 causes identical coke consumption rate decrease as by reducing its wear by 0.2. Investigation results are given in 14 diagrams. 8 references.

Kolano, A.; Mazanek, K.; Brachucy, A.

1984-04-01

 
 
 
 
121

Effect of coke reactivity and nut coke on blast furnace operation  

Energy Technology Data Exchange (ETDEWEB)

Two measures for coke saving and increase in blast furnace efficiency related to coke characteristics - reactivity and size - are discussed in this paper. Modern blast furnace operation with low coke rate and high injection rate causes a change in coke quality requirements. A discussion has arisen recently about highly reactive coke. Here, a theoretical analysis of influence of coke reactivity on the thermal reserve zone, direct reduction and carbon consumption in the blast furnace has been undertaken. Experiments have been performed using non-standard test scenarios that simulate coke behaviour under real blast furnace operating conditions. Coke reactivity and microstructure have also been investigated under the impact of alkali and pulverised coal ash and char. Operation of many blast furnaces has proved the possibility of coke saving and increase in productivity when using small-sized coke (so-called nut coke) mixed with the burden, but the reasons for this phenomenon, and consequently the limit for nut coke consumption, are still not very clear. An analytical method and cold model simulations have been used to quantify the change in shaft permeability and furnace productivity when using nut coke.

Babich, A.; Senk, D.; Gudenau, H.W. [RWTH Aachen, Aachen (Germany)

2009-04-15

122

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

123

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

124

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.

125

Fuel combustion in the blast furnace raceway zone  

Energy Technology Data Exchange (ETDEWEB)

When air is introduced horizontally into the packed bed of carbonaceous particles, a heterogeneous combustion zone forms within the packed bed. Depending on the relative gas velocity at the point of introduction of the gas and the size of the packed-bed particles, these combustion zones vary from relatively quiescent regions to zones in which turbulent, high-speed, rotational motion of the particles occurs. It is shown in this review that in the past studies in this field have mostly been carried out as a result of investigations into the iron-making blast furnace. In the conducting of this research, four approaches to the problem have been adopted, these being: (i) experiments on laboratory models at room temperature, (ii) experiments on hot models in which the combustion occurs at high temperature but where a small scale of operation applies; (iii) experiments on full-scale packed beds during or after commercial operation and (iv) theoretical studies which simulate the system. Taken as a whole, the work has shown that the shape, size and combustion characteristics of packed-bed turbulent combustion zones are complex and depend on the physical and chemical nature of the carbonaceous particles which comprise the packed bed and the properties of the injected oxidising gas and any supplementary fuels employed in the process. 64 references.

Burgess, J.M.

1982-01-01

126

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

127

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)

128

Coal combustion under conditions of blast furnace injection. Final technical report, September 1, 1992--August 31, 1993  

Energy Technology Data Exchange (ETDEWEB)

A potentially new use for Illinois coal is as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. During the first phase of this project a number of the objectives were realized, specifically: (1) a blast furnace sampling system was developed and used successfully to collect samples inside an active furnace; (2) two sets of blast furnace samples were collected and petrographic analysis showed that char derived from injected coal is entering the reduction zone of the furnace; (3) a coal/char sampling probe was designed and fabricated; (4) the completion of a program of reactivity experiments on the injected coal char, blast furnace coke and Herrin No. 6 char. The results of the reactivity experiments indicate that Herrin No. 6 coal is similar or even superior to coals now being used in blast furnace injection and that additional testing is warranted.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Case, E.R. [Armco, Inc., Middletown, OH (United States). Research and Technology Div.

1993-12-31

129

Evaluation of efficiency of working time of equipment in blast furnace department  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: The main aim of the paper is the evaluation of efficiency of working time of equipment in blast furnace department with the use of Overall Equipment Effectiveness (OEE and PAMCO method.Design/methodology/approach: The investigation was made for blast furnace department in Polish steel plant. Two methods: OEE and PAMCO was used. The analysis covers the period of 7 years. The analysis was made based on different data: different types of time connected whit work of blast furnaces, interruption in blast furnace work, level of pig iron production, unit production time and quantity of non-conformance production.Findings: Performed research made it possible to determine the level of efficiency of blast furnace department. It can be concluded that working time in this department is used efficient. Factors that reduce efficiency are usually not-dependent on the company: mainly are connected with the situation on the steel market.Research limitations/implications: It is necessary to continue the research in order to assess individual blast furnaces. That analysis may enable to show if these units has the same level of efficiency and if they are affected by the same factors in the same way.Practical implications: Optimal utilization of capacity and working time of machines and equipment are important for the reduction of production costs. Use of OEE and PAMCO methods helps to assess the level of efficiency of working time and allow to find factors that has great importance for level of efficiency.Originality/value: Results of this analysis can be taken into consideration by blast furnace department under study. Analysis can help to assess the level of efficiency and find factors that influence on it.

E. Kardas

2012-12-01

130

Extended use of helium tracing technique and assessment of blast furnace shaft permeability  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace is a countercurrent reactor in which a reducing gas is produced by coke gasification with the oxygen blown in via tuyeres. The reducing gas flows upwards, reducing the iron ores charged at the top of the furnace. It is a very complex process with many influencing and correlating factors. Its productivity is the quotient between possible gas throughput per unit of time and required specific gas generation for 1 tonne of hot metal obtained, and its permeability is a measure of the gas ability to pass through the bed of solid materials. The objective of 'high levels of injection of pulverised coal' is not only compatible with productivity, but also even necessary to increase blast furnace productivity. In this sense the helium tracing technique consists of injecting He at the tuyeres with its arrival at the blast furnace top being detected by a mass spectrometer. With this measurement it is possible to define the transfer time as the delay between the injection moment and the time when the helium concentration reaches 10% of the maximum detected level. Calculated variables from the measurements allow a concise characterisation of the blast furnace state. These gas transfer measurements can be considered as a new tool to evaluate the state of a furnace at a specific moment. The main advantage will be that by employing only one measurement it will be possible to evaluate the furnace state.

Carrascal, D.; Barea, R.; Martin, R.; Mochon, J.

2008-01-15

131

An Integrated Model of Coal/Coke Combustion in a Blast Furnace  

Science.gov (United States)

A three-dimensional integrated mathematical model of the combustion of pulverized coal and coke is developed. The model is applied to the region of lance-blowpipe-tuyere-raceway-coke bed to simulate the operation of pulverized coal injection in an ironmaking blast furnace. The model integrates two parts: pulverized coal combustion model in the blowpipe-tuyere-raceway-coke bed and the coke combustion model in the coke bed. The model is validated against the measurements in terms of coal burnout and gas composition, respectively. The comprehensive in-furnace phenomena are simulated in the raceway and coke bed, in terms of flow, temperature, gas composition, and coal burning characteristics. In addition, underlying mechanisms for the in-furnace phenomena are analyzed. The model provides a cost-effective tool for understanding and optimizing the in-furnace flow-thermo-chemical characteristics of the PCI process in full-scale blast furnaces.

Shen, Y. S.; Guo, B. Y.; Yu, A. B.; Austin, P.; Zulli, P.

2010-03-01

132

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

Science.gov (United States)

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

Chu, Yanxu; Gao, Chuanhou; Liu, Xiangguan

2010-09-01

133

Recovery Act: ArcelorMittal USA Blast Furnace Gas Flare Capture  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) awarded a financial assistance grant under the American Recovery and Reinvestment Act of 2009 (Recovery Act) to ArcelorMittal USA, Inc. (ArcelorMittal) for a project to construct and operate a blast furnace gas recovery boiler and supporting infrastructure at ArcelorMittal’s Indiana Harbor Steel Mill in East Chicago, Indiana. Blast furnace gas (BFG) is a by-product of blast furnaces that is generated when iron ore is reduced with coke to create metallic iron. BFG has a very low heating value, about 1/10th the heating value of natural gas. BFG is commonly used as a boiler fuel; however, before installation of the gas recovery boiler, ArcelorMittal flared 22 percent of the blast furnace gas produced at the No. 7 Blast Furnace at Indiana Harbor. The project uses the previously flared BFG to power a new high efficiency boiler which produces 350,000 pounds of steam per hour. The steam produced is used to drive existing turbines to generate electricity and for other requirements at the facility. The goals of the project included job creation and preservation, reduced energy consumption, reduced energy costs, environmental improvement, and sustainability.

Seaman, John

2013-01-14

134

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

Directory of Open Access Journals (Sweden)

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.

MAHSHAD YAZDANIPOUR

2011-03-01

135

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

Science.gov (United States)

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.

Chu, Yanxu; Gao, Chuanhou; Liu, Xiangguan

2010-09-01

136

Coke reactivity under blast furnace conditions and in the CSR/CRI test  

Energy Technology Data Exchange (ETDEWEB)

The present work aims to study the high-temperature strength of coke. Mechanisms of disintegration were evaluated using basket samples charged into LKAB's experimental blast furnace prior to quenching and dissection. Coke charged into basket samples was analysed with CSR/CRI tests and compared with treated coke from the blast furnace. Results from tumbling tests, chemical analyses of coarse and fine material, as well as light optical microscopy studies of original and treated coke have been combined and evaluated. The results indicate a correlation between the ash composition and the CSR values. Differences in the texture of the coke were noted with light optical microscopy, and a significant change in the coke texture during the CSR/CRI test conditions was found. The results suggest that the main reaction between coke and CO{sub 2} took place in isotropic areas, which was especially pronounced in coke with a low CSR. Signs of degradation were apparent throughout the coke pieces that have undergone CSR/CRI testing, but were less observable in coke reacted in the blast furnace. The results indicate that reaction with CO{sub 2} is generally limited by the chemical reaction rate in the CSR/CRI test, while in the blast furnace the reaction is limited by the diffusion rate. Coke degradation is therefore mostly restricted to the coke surface in the blast furnace. (orig.)

Lundgren, Maria; Bjoerkman, Bo [Lulea Univ. of Tech., Lulea (Sweden); Sundqvist Oekvist, Lena [Swerea MEFOS, Lulea (Sweden)

2009-06-15

137

Coal combustion under conditions of blast furnace injection; [Quarterly] technical report, September 1--November 30, 1993  

Energy Technology Data Exchange (ETDEWEB)

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This study is unique in that it will be the first North American effort to directly determine the nature of the combustion of coal injected into a blast furnace. This proposal is a follow-up to one funded for the 1992--1993 period. It is intended to complete the study already underway with the Armco Inc. steel company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals f or such use.

Crelling, J.C.

1993-12-31

138

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

139

Similarities between pinch analysis and classical blast furnace analysis methods : possible improvement by synthesis  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace process is a very important unit process in the metallurgical industry. The blast furnace reduces iron oxide to molten iron in a single process. However, it is also part of a bigger system consisting of peripheral equipment such as hot stoves, blowers, cooling equipment and raw materials handling. This paper described the different methods that have been developed to interpret the blast furnace process. In particular, it described and compared the Reichardt and Rist methods with pinch analysis which was developed in the 1970s as a method for energy analysis and optimization of industrial systems. It described various methods for analyzing energy and mass exchange with reference to Reichardt's blast furnace heat balances; pinch analysis for energy integration; pinch analysis for mass integration; and, Rist's diagram for carbon, oxygen and hydrogen balances in iron ore reduction. The challenges, opportunities and advantages of pinch analysis were also discussed. Pinch analysis uses temperature-enthalpy diagrams to graphically evaluate the heat exchange capability of a defined system. It has been described as an interesting method for establishing the blast furnace heat balance. 16 refs., 3 tabs., 14 figs.

Ryman, C. [Metallurgical Research Inst., Lulea (Sweden)]|[Lulea Univ. of Technology, Lulea (Sweden). Div. of Energy Engineering; Grip, C.E. [SSAB Tunnplat AB, Lulea (Sweden)]|[Lulea Univ. of Technology, Lulea (Sweden). Div. of Energy Engineering; Franck, P.A. [CIT Industriell Energianalys AB, Gothenburg (Sweden); Wikstrom, J.O. [Metallurgical Research Inst., Lulea (Sweden)

2005-07-01

140

Control upgrade of Inland No. 7 blast furnace using distributed open architecture  

Energy Technology Data Exchange (ETDEWEB)

Distributed open architecture systems provide significant potential benefits in the application of process control automation in the iron and steel industry. For these reasons, Inland Steel selected an open architecture system for controlling the No. 7 blast furnace. The new system replaces an existing control system commissioned in 1980. It offers four major advantages compared with a closed system: (1) Cost savings of 30 to 50% on hardware and software. (2) Improved operating efficiency -- The wide band-width and high memory capacity permits the production of hot metal with fewer interruptions to the process. (3) Reliability -- The system offers a tenfold overall improvement in MTBF compared with the current on-line system. Moreover, redundant, continually operating control computers, G 2[sup VME] nodes (with reflective memory), and high security multiplexor I/O on all critical areas insure non-stop operation of process-critical functions during occasional malfunctions, thereby avoiding costly blast furnace shutdown. (4) Protection of blast furnace components -- By enabling the cost-effective monitoring of a large number of temperature points throughout the furnace hearth, for example, the system could extend the 7 to 12-year life expectancy of the furnace lining by two to three years. Configuration of a new, open architecture blast furnace control system installed in place of a 10-year old single vendor system is described.

Hatfield, P.L. (Inland Steel Flat Products Co., East Chicago, IN (United States)); Higgins, M.J. (Computer Products, Inc., Mars, PA (United States))

1994-10-01

 
 
 
 
141

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)

142

On-line ultrasonic system for measuring thickness of the copper stave in the blast furnace  

Science.gov (United States)

The blast furnace is used make molten iron from sintered ore and the cokes in the steel industry. Recently, the copper stave cooling system placed on inner face of the blast furnace body to protect the steel shell from heat. In the high temperature environment, the wear between the stave and the material makes the cooling stave thinning by the downward movement of the materials in the blast furnace. It was impossible to access the copper stave with the ultrasonic sensor for measuring thickness because the copper stave is covered with the steel shell and there is backing refractory between the stave and the steel shell. The unique ultrasonic sensor which can approach the cooling stave through the cooling line was developed to measure thickness. The thickness can be measured with portable ultrasonic thickness sensor and can be monitored continuously with embedded sensors.

Choi, Sang-Woo; Kim, Dohoon

2012-05-01

143

Model for Fast Evaluation of Charging Programs in the Blast Furnace  

Science.gov (United States)

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.

Mitra, Tamoghna; Saxén, Henrik

2014-08-01

144

The cycle and effect of zinc in the blast-furnace process  

Directory of Open Access Journals (Sweden)

Full Text Available This article analyzes the effect of zinc in the blast furnace process and it also analysis its contents in the input and output raw materials. The results obtained in the long-term research project will be used as data here. The removal of zinc from the input raw materials is very difficult already in the sinter production stage. This is due to its uniform distribution in the raw materials, but also due to the fact that it does not transfer into gas phase during the sintering process. The content of Zinc compounds was experimentally measured in the lining. The quantity of penetrated Zinc is different in different parts of the blast furnace. As demonstrated by the research, zinc repeatedly enters the blast furnace process, which leads to its circulation.

M. Hendrych

2013-04-01

145

Coal combustion under conditions of blast furnace injection. Technical report, March 1, 1994--May 31, 1994  

Energy Technology Data Exchange (ETDEWEB)

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This investigation is significant to the use of Illinois coal in that the limited research to date suggests that coals of low fluidity and moderate to high sulfur and chlorine contents are suitable feedstocks for blast furnace injection. This proposal is a follow-up to one funded for the 1992-93 period. It is intended to complete the study already underway with the Armco Inc. Steel Company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals for such use. During this quarter samples of two feed coals and the IBCSP 112 (Herrin No. 6) were prepared for reactivity testing and compared to blast furnace coke, and char fines taken from an active blast furnace. As the initial part of a broad reactivity analysis program, these same samples were also analyzed on a thermogravimetric analyzer (TGA) to determine their combustion and reactivity properties.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States)

1994-09-01

146

Approach for Minimizing Operating Blast Furnace Carbon Rate Using Carbon-Direct Reduction (C-DRR) Diagram  

Science.gov (United States)

An approach for reducing input carbon rate of a blast furnace using carbon-direct reduction (C-DRR) diagram has been developed. The role of shaft efficiency, blast input conditions, and heat loss rate in reducing the carbon rate has been brought out. A two-zone thermochemical model has been used to develop C-DRR diagrams for analyzing operating data of a furnace as well as predicting conditions for reducing its carbon rate. The model can be integrated with the control system of a blast furnace for driving an operating furnace to reduce carbon rates.

Paul, Soumavo; Roy, S. K.; Sen, P. K.

2013-02-01

147

Possibility of blast furnace coke substitution by coal dust under conditions of Czechoslovakia  

Energy Technology Data Exchange (ETDEWEB)

Discusses partial coke substitution by pulverized coal in a blast furnace. The coke quality profile in a blast furnace is explained. An analysis of coke lumps and free space available along the furnace is made. Performance of the coke bed is evaluated by blowing up to 200 kg of pulverized fuel per t of coke into the furnace and withdrawing a comparable amount of coke from it. The general coke quality in Czechoslovakia is described as lower than in Western Europe or Japan (unit slag production is 600 kg compared to 300 kg for Western European coke). Tests of utilizing pulverized coal were carried out for 3 coke qualities: good domestic, poor domestic, and very good. Three comparative charts are shown for coke substitution of 111 to 130 kg/t and theoretical combustion temperatures ranging from 2,130 to 2,227 C. Various thermal parameters are calculated, such as oxygen content in combustion air. 7 refs.

Bilik, J.; Kret, J. (Wyzsza Szkola Gornicza, Ostrava (Czechoslovakia))

1992-06-01

148

Detection and Quantification of the Dead Man Floating State in the Blast Furnace  

Science.gov (United States)

The lower part, the hearth, is a crucial region of the ironmaking blast furnace. The life length of it often determines the campaign length of the furnace and the thermal state and permeability of the hearth exert strong influence on liquids drainage and hot metal chemistry. In order to operate the furnace efficiently, the hearth state should be controlled, but the conditions in the hearth are extremely hostile with little possibility to carry out direct measurements. This article presents a set of methods and models through which the floating of the hearth coke bed, the dead man, can be assessed. Data from three industrial blast furnaces illustrate how a systematic analysis of available measurements, in combination with results of mathematical models of the phenomena in the hearth, can successfully detect and quantify the dead man floating state.

Brännbacka, Johnny; Saxén, Henrik; Pomeroy, Dave

2007-06-01

149

Cold model of coal gas component concentration distribution in blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

Primary distribution of coal gas in blast furnace raceway has an important effect on blast furnace ironmaking process. The coal gas component concentration distribution was studied experimentally using a three-dimensional cold model. The results showed that CH{sub 4} concentration diminishes along with the height increasing on vertical section of raceway, and the concentration is the highest in the bottom of raceway. CH{sub 4} concentration increases gradually along the raceway depth with the lowest concentration value in front of the tuyere. The distribution of CH{sub 4} concentration has different characteristics in different raceway zones.

Sheng-fu Zhang; Liang-ying Wen; Chen-guang Bai; Gui-bao Qiu; Mei-long Hu; Xue-wei Lu [Chongqing University, Chongqing (China). College of Materials Science and Engineering

2009-11-15

150

Comparison of local stress values obtained by two measuring methods on blast furnace shell  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes measuring of time behaviour specified for local stress increments on the blast furnace shell that were performed using strain gauge sensors. These results are compared with values obtained by means of the second specific measuring method. There is also presented in this paper a commentary and discussion concerning the measured time behaviour obtained from the both measuring methods. This article presents results from another of experimental analysis series concerning the blast furnace shell in one concrete metallurgical plant.

P. Bigoš

2015-01-01

151

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2008-07-01

152

Composite cements containing natural pozzolan and granulated blast furnace slag  

Directory of Open Access Journals (Sweden)

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.

Irassar, E. F.

2006-09-01

153

Optimization of a Steel Plant with Multiple Blast Furnaces Under Biomass Injection  

Science.gov (United States)

The allocation of resources between several blast furnaces in an integrated steelmaking plant is studied with the aim of finding the lowest specific operation cost for steel production. In order to reduce the use of fossil fuels, biomass was considered as an auxiliary reductant in the furnace after partial pyrolysis in an external unit, as a complement to heavy fuel oil. The optimization considers raw material, energy, and emission costs and a possible credit for sold power and heat. To decrease computational requirements and to guarantee that the global optimum is found, a piecewise linearized model of the blast furnace was used in combination with linear models of the sinter-, coke-, and power plants, hot stoves, and basic oxygen furnace. The optimization was carried out under different constraints on the availability of some raw materials as well as for different efficiencies of the hot stoves of the blast furnaces. The results indicate that a non-uniform distribution of the production between the furnaces can be advantageous, and some surprising findings concerning the optimal resource allocation under constrained operation are reported.

Wiklund, Carl-Mikael; Pettersson, Frank; Saxén, Henrik

2013-04-01

154

Energy analysis of a blast-furnace system operating with the Corex process and CO{sub 2} removal  

Energy Technology Data Exchange (ETDEWEB)

The integration of the COREX process with the blast-furnace process, the installation of CO{sub 2} removal and gas-and-steam CHP plant displays many energy and ecological advantages. The application of COREX gas after the removal of CO{sub 2} as hot reducing gas leads first of all to a saving of coke. Besides the reduction of the consumption of coke, also the consumption of blast, high-purity oxygen, the amount and lower heating value (LHV) of blast-furnace gas are changed, as well as the production of electricity in the recovery turbine, the consumption of blast-furnace gas in the Cowper stoves and the amount of blast-furnace gas supplied to the gas-energy subsystem of the ironworks. Related to a unit amount of pig iron, these quantities are called energy characteristics of the blast-furnace assembly. They may be used to assess the energy process effects of applying COREX gas in the blast-furnace process. In order to assess the influence of injecting COREX gas into the thermal reserve zone, the zone balance method of the blast-furnace process has been used. (author)

Ziebik, Andrzej; Lampert, Krzysztof; Szega, Marcin [Institute of Thermal Technology, Silesian University of Technology, Konarskiego 22, 44-101 Gliwice (Poland)

2008-02-15

155

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

Science.gov (United States)

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

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

2011-12-01

156

Calculation and Analysis of Liquid Holdup in Lower Blast Furnace by Model Experiments  

Science.gov (United States)

A hydromechanics experiment on the countercurrent flow of gas and liquid simulating the flow conditions in the lower blast furnace was carried out. A cold model of a packed bed with various packing materials and liquids was used to study the holdup of liquid. Correlations for static holdup, dynamic holdup, and total holdup were obtained. A good agreement was found between the calculated and experimental data. A mathematical model simulating the flow fields was applied to study the effect of liquid holdup in blast furnace. The results of the model calculation show that static holdup is the determinant of the total holdup of molten materials when the blast furnace works in stable condition. The slag phase generally reaches flooding holdup ahead of the hot metal. The radial distribution of gas flow is almost not influenced by the holdup of molten materials, but it has a greater influence on the pressure drop. The size of coke has far greater influence on static holdup than liquid properties does. The study is useful for acquiring a deeper understanding of the complex phenomena in the blast furnace and for determining appropriate operational actions under different production conditions.

Xiong, Wei; Bi, Xue-Gong; Wang, Guo-Qiang; Yang, Fu

2012-06-01

157

A model for estimating the viscosity of blast furnace slags with optical basicity  

Science.gov (United States)

Viscosity is an important physical property of blast furnace slags and has a great influence on blast furnace operations. Because of time consumption and difficulties encountered during high temperature experimental measurement, viscosity data are also limited, so a reasonable and accurate estimation model is required to provide the data for controlling and optimizing the blast furnace process. In the present study a viscosity model was proposed for blast furnace slags. In the model the activation energy was calculated by the optical basicity corrected for cations required for the charge compensation of AlO{4/5-}, and the temperature dependence was described by the Weymann-Frenkel equation. The estimated viscosity values of the CaO-Al2O3-SiO2, CaO-Al2O3-SiO2-MgO, and CaO-Al2O3-SiO2-MgO-TiO2 systems fit well with experiment data, with the mean deviation less than 25%.

Hu, Xiao-jun; Ren, Zhong-shan; Zhang, Guo-hua; Wang, Li-jun; Chou, Kuo-chih

2012-12-01

158

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

Directory of Open Access Journals (Sweden)

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.

A. Konstanciak

2012-12-01

159

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

Science.gov (United States)

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.

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

2014-07-01

160

Utilisation of national resources in the manufacture of pig iron in coke blast furnaces. [Argentina  

Energy Technology Data Exchange (ETDEWEB)

Part of the paper deals with the possibility of using Argentinian coals in the charge at Somisa's coke ovens, as well as petroleum residues. Historical data are given on coke oven blend composition and coke quality, blast furnace coke quality specifications are quoted, characteristics of Rio Turbio coal are tabulated and methods of testing coal for coking are described.

Bianconi, N.

1985-01-01

 
 
 
 
161

Slag optimization in charcoal blast furnaces; Otimizacao de escorias de altos-fornos a carvao vegetal  

Energy Technology Data Exchange (ETDEWEB)

In this work, it is shown the optimum composition of charcoal blast furnace slag using phase diagrams. The results are compared with industrial data and some possible changes in slag composition and mass are also suggested. (author) 3 refs., 5 figs., 3 tabs.

Castro, Luiz Fernando Andrade de; Tavares, Roberto Parreiras; Figueira, Renato Minelli; Lopes, Leonardo Braga Polido; Goncalves, Alexandre Ferreira [Associacao Brasileira de Metais (ABM), Sao Paulo, SP (Brazil)

1987-12-31

162

Studies of charging stream trajectories and burden distribution in the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

This work discusses the sensitivity of key blast furnace performance parameters to different gas flow distributions achieved by altering the burden distribution. The changes in burden distribution are brought about by different charging stream trajectories, and methods developed and evaluated for measuring the trajectories both on and off line are described.

McCarthy, M.J.; Mayfield, P.L.; Zulli, P.; Rex, A.J.; Tanzil, W.B.U.

1993-01-01

163

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

Science.gov (United States)

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.

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

2014-08-01

164

Determination of thermal histories of coke in blast furnace through X-ray analysis  

Energy Technology Data Exchange (ETDEWEB)

A study has been undertaken to identify the source of coke fines sampled from the deadman area of the blast furnace. Using measurements of the coke crystallite dimension L{sub C}, it was established that some of the fines found in the deadman area of a blast furnace were not simply the degradation products of the lump coke in this area. The L{sub C} was measured using standard X-ray analysis techniques. The coke fines had a higher L{sub C} than the coke lump and therefore have experienced a higher maximum temperature than the associated coke lump. This finding has been interpreted as at least some of the coke fines found in the deadman area (lower temperature region) have been blown there from the raceway by the high velocity hot blast.

Monaghan, B.J.; Nightingale, R.; Daly, V.; Fitzpatrick, E.

2008-01-15

165

Pulverized coal injection in blast furnaces at ArcelorMittal Tubarao (AMT)  

Energy Technology Data Exchange (ETDEWEB)

The main factors that influence the performance of coal injected into blast furnaces include coal properties, combustion conditions and the equipment used in the plants for grinding, transportation and injection of coal. This paper focused on coal properties and the main operational control changes in the no.1 blast furnace at ArcelorMittal Tubarao. The furnace was modified from an all coke operation to a pulverized coal injection (pci) operation in order to ensure high productivity, low fuel consumption and longer service life. ArcelorMittal Tubarao has developed a coal buying model based on energy balance and the chemical analysis of ash. In the energy balance, the ratio between the heat supplied by carbon combustion and the heat consumed by the cracking of water and volatiles results in the potential rate of coke replacement by coal. 5 refs., 1 tab., 10 figs.

Klein, C.A.; Fujihara, F.K.; Defendi, G.A.; Tauffer Barros, R.J. [ArcelorMittal Tubarao, Serra (Brazil). Ironmaking Dept.

2008-07-01

166

Mathematical model of blast furnace raceway zone with pulverized coal and fine ore injection  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model of blast furnace raceway zone with pulverized coal (PC) and fine ore injection was developed to describe the reaction behaviour of injected PC and fine ore. The model is based on differential balances of mass and heat, taking account of the reaction kinetics and heat transfer of PC, coke, fine ore and gases. The kinetic parameters of thermal decomposition and reduction of fine ore were determined by laboratory testing. The kinetic parameters of PC and coke combustion were determined by applying the model to an experimental combustion furnace and to an actual blast furnace with coke and PCI operations. Furthermore, the raceway phenomena with simultaneous injection of PC and fine ore were predicted and the effects of operating conditions on reaction in a raceway were studied using the model.

Xiao, X.; Nozawa, K.; Sasahara, S.; Shimizu, M.; Inaba, S.

1995-06-01

167

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2002-01-21

168

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 land to the removal of this resource from landfills

169

Data-driven analysis of blast furnace tuyere-level and hearth conditions  

Energy Technology Data Exchange (ETDEWEB)

This thesis is focused on the high temperature region of the ironmaking blast furnace, developing models and methods for throwing light on phenomena inside the tuyere and raceway region and the furnace hearth. The work studies and applies the existing process information consisting of measurements from the process and laboratory analyzes of different samples taken regularly from the furnace. A model for monitoring the blast distribution is created. The model considers the partial combustion of the injected auxiliary reductant, heavy oil, in the tuyeres, and it can also be used in what-if-analysis to examine the influence of different parameters on the blast distribution and other related variables. Data from tuyere core drillings is analyzed and a correlation with thermal cycles observed in the heart is found. The thermal cycles are further studied by an analysis of balance studying accumulation/depletion of sulfur in the furnaces. A method for analyzing data from complex processes, based on the differences observed in the data rather than the absolute values, is presented and used to study the complex interactions between reductant parameters and hot metal properties. (orig.)

Helle, M.

2009-07-01

170

Application of optical basicity to viscosity of high alumina blast furnace slags  

Directory of Open Access Journals (Sweden)

Full Text Available The composition and properties of blast furnace slags greatly affect the furnace productivity and the quality of hot metal produced. Viscosity is an important physical property of slags, strongly influenced by the chemical composition, structure and the temperature. Experimental measurement of slag viscosity requires high temperature equipment and is time consuming. Therefore, chemical parameters are used to identify trends in viscosity as function of chemical composition. Limited information is available for High Alumina Blast Furnace Slags, since much of the open literature deals with Low Alumina Slags, with alumina content less than 15 weight percentage. High Alumina slags (alumina content in the range of 15% to 30% are predominantly encountered in Indian Blast Furnaces. It appears that these slags have higher viscosity and lower sulphide capacity than the low alumina slags. The effect of chemical composition / ionic structure on viscosity has been interpreted in this work, using the chemical parameter of optical basicity. Data reported in the literature have been used, along with the values of liquidus temperature, for high alumina slags. Three slag systems, i.e., CaO-Al2O3-SiO2, CaO-Al2O3-SiO2-MgO and CaO-Al2O3-SiO2-MgO-TiO2 have been considered in this work. The trends observed are discussed in the paper.

Ghosh D.

2010-01-01

171

Soaking bar technology on a single-taphole blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Soaking bar technology is not new and has been practiced for many years in Europe and Asia. Based on two years experience at the Gary works, the following conclusions can be reached: The technology is viable, especially on high productivity facilities; Training is important to insure a smooth transition of operation; Taphole clay is the single most important part of the technology; Soaking bar practice allows a shift in single-taphole furnace casting philosophy to a longer, slower casting mode to more closely match furnace smelting rate and, thus, enhance stability of furnace operations. Existence, or addition, of facilities such as tilting spouts and/or slag pits will further enhance the stabilizing effects of soaking bar practice. Economics are site specific and can be attractive under the appropriate circumstances. Quality parameters may be enhanced by the use of this technology.

O' Donnell, E.M. (USX Corp., Monroeville, PA (United States). South Blast Furnaces); Mikaloff, G.G. (USX Corp., Monroeville, PA (United States). Gary Works); Yount, J.G. Jr. (USX Corp., Monroeville, PA (United States). U.S. Steel Group)

1993-10-01

172

Modelling and prediction of pig iron variables in the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-12-31

173

Fundamental study on carbon composite iron ore hot briquette used as blast furnace burden  

Energy Technology Data Exchange (ETDEWEB)

Carbon composite iron ore hot briquette (CCB) is the product of fine iron ore and fine coal by hot briquetting process, which attracts more and more attention as a new type of ironmaking raw materials aiming to improve the operation efficiency and reduce the coke consumption of blast furnace. This paper is devoted to experimental study on metallurgical properties of CCB and numerical simulation of the BF operation with CCB charging. At first, the metallurgical properties of CCB, including cold crushing strength, RDI, RSI, reducibility, high temperature strength, and softening and dripping are experimentally tested and compared with the common burdens, which revealed that the CCB possesses the required metallurgical properties and is suitable to use as the blast furnace burden. Then, the effects of charging CCB on the dripping properties of comprehensive burdens are elucidated based on the experiments under simulated blast furnace conditions. The results showed that the maximum charging ratio of CCB in the iron burdens is 40%-50% for achieving appropriate dripping properties of the mixed burdens. Finally, a multi-fluid blast furnace model is used to simulate BF operation with CCB charging. According to model simulations, charging CCB will cause the temperature level to decreases in the furnace and the location of the cohesive zone shifts downward. On the other hand, the productivity tends to increase while coke rate and total reducing agent rate decrease, the heat efficiency improves remarkably and the operation performance of BF is effectively enhanced. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Chu, Man-sheng; Liu, Zheng-gen; Wang, Zhao-cai [Institute of Ferrous Metallurgy, Northeastern University, Shenyang (China); Yagi, Jun-ichiro [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University (Japan)

2011-05-15

174

Research on carbonaceous substance of blast furnace dust under different PCI rates at Shouqin's No.1 blast furnace  

Energy Technology Data Exchange (ETDEWEB)

The microstructure of blast furnace (BF) dust (gravitational dust and bag dust of hop pocket) under increased pulverized coal injection (PCI) rate at Shouqin's No. 1 BF was investigated by means of microscopic analysis. The percentage of surface area of unconsumed coal and coke particles was determined under different PCI rates. The effect of increased PCI rate on the carbon mass fraction in BF dust and consequently on the unburnt coal and coke particles as well as the utilisation factor of pulverised coal are given for different PCI rates at Shouqin's No. 1 BF. 5 refs., 2 figs., 4 tabs.

Ding, R.; Wu, K.; Wu, W.; Fei, S.; Zhang, J.; Ni, B. [Shouqin Metal Company Ltd., Qinhuangdao (China). Ironmaking Dept.

2008-11-15

175

Hot metal temperature prediction in blast furnace using advanced model based on fuzzy logic tools  

Energy Technology Data Exchange (ETDEWEB)

The present work presents a model based on fuzzy logic tools to predict and simulate the hot metal temperature in a blast furnace (BF). As input variables this model uses the control variables of a current BF such as moisture, pulverised coal injection, oxygen addition, mineral/coke ratio and blast volume, and it yields as a result of the hot metal temperature. The variables employed to develop the model have been obtained from data supplied by current sensors of a Spanish BF In the model training stage the adaptive neurofuzzy inference system and the subtractive clustering algorithms have been used.

Martin, R.D.; Obeso, F.; Mochon, J.; Barea, R.; Jimenez, J.

2007-05-15

176

The Iron Blast Furnace: A Study in Chemical Thermodynamics.  

Science.gov (United States)

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.…

Treptow, Richard S.; Jean, Luckner

1998-01-01

177

Investigation of the effect of blast furnace raceway temperatures on coke properties  

Energy Technology Data Exchange (ETDEWEB)

Details of the design and operation of the induction furnace constructed in the first stage of the project are reported. The results of a series of trials carried out in order to investigate the effects of blast furnace raceway temperatures on coke properties and the mechanisms involved are presented and discussed. The results of the work showed that thermal effects alone had little effect on coke size and that thermal disintegration of coke particles was not a factor. All of the cokes suffered a reduction in strength, in terms of abrasion resistance, which increased with increasing temperature. The level of strength reduction was also related to catalytic graphitisation by iron present in the coke ash, the level of alkalis in the coke and the loss of the ash components by reaction and volatilisation at high temperatures. The ash contents of the cokes were drastically reduced by heating to raceway temperatures. The loss of ash was reflected by the loss of sulphur and the volatile alkali and alkaline earth elements below 2000{degree}C and silicon and aluminium at higher temperatures. In general the thermophysical changes in the induction furnace were less than those observed in the blast furnace while the thermochemical changes were more marked. These effects were considered to be the result of the lower heating rates, more uniform heating conditions and longer soaking times experienced by the induction furnace cokes. 19 refs., 40 figs., 37 tabs.

Willners, R.R.; Atkinson, J.C. (British Steel plc, London (UK))

1991-01-01

178

The analysis of quality of ferrous burden materials and its effect on the parameters of blast furnace process  

Directory of Open Access Journals (Sweden)

Full Text Available The analysis of the effect of the quality of ferrous burden materials on the parameters of blast furnace process is presented in this paper. First, the quantitative and qualitative analysis of ferrous burden materials used in blast furnace process was made. The chemical composition, mainly iron content, is the basic quality parameter taken into consideration. Then, the dependence of parameters of process on the quality parameters of burden materials will be calculated.

E. Kardas

2013-04-01

179

Application of encapsulated lightweight aggregate impregnated with sodium monofluorophosphate as a self-healing agent in blast furnace slag mortar:  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper studies the potential of using expanded clay lightweight aggregate impregnated with sodium monofluorophosphate (Na2FPO3) solution which is eventually encapsulated by a cement paste layer to produce a self-healing system in blast furnace slag cement mortars. It was found that the technique significantly improved the quality of the interfacial transition zone in mortars subjected to carbonation shrinkage. Consequently the frost salt scaling durability of blast furnace slag mortars wa...

Sisomphon, K.; Copuroglu, O.; Fraaij, A.

2011-01-01

180

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

 
 
 
 
181

Mathematical Model of the Solid Flow Behavior in a Real Dimension Blast Furnace  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A mathematical model based on the continuum mechanic concept has been developed to describe the profile of solid particles in an industrial scale blast furnace. The focus is the in-furnace conditions and its characteristics such as the shape and size of the deadman. The Navier-Stokes differential equation for multi-phase multi-dimensional space has been used to describe the behavior of existing phases. The equation has been modified to make it possible to describe the dual nature of the solid...

Safavi Nick, Reza

2012-01-01

182

Extracting the core indicators of pulverized coal for blast furnace injection based on principal component analysis  

Science.gov (United States)

An updated approach to refining the core indicators of pulverized coal used for blast furnace injection based on principal component analysis is proposed in view of the disadvantages of the existing performance indicator system of pulverized coal used in blast furnaces. This presented method takes into account all the performance indicators of pulverized coal injection, including calorific value, igniting point, combustibility, reactivity, flowability, grindability, etc. Four core indicators of pulverized coal injection are selected and studied by using principal component analysis, namely, comprehensive combustibility, comprehensive reactivity, comprehensive flowability, and comprehensive grindability. The newly established core index system is not only beneficial to narrowing down current evaluation indices but also effective to avoid previous overlapping problems among indicators by mutually independent index design. Furthermore, a comprehensive property indicator is introduced on the basis of the four core indicators, and the injection properties of pulverized coal can be overall evaluated.

Guo, Hong-wei; Su, Bu-xin; Zhang, Jian-liang; Zhu, Meng-yi; Chang, Jian

2013-03-01

183

A Differential Scanning Calorimetry Method for Construction of Continuous Cooling Transformation Diagram of Blast Furnace Slag  

Science.gov (United States)

The continuous cooling crystallization of a blast furnace slag was studied by the application of the differential scanning calorimetry (DSC) method. A kinetic model describing the correlation between the evolution of the degree of crystallization with time was obtained. Bulk cooling experiments of the molten slag coupled with numerical simulation of heat transfer were conducted to validate the results of the DSC methods. The degrees of crystallization of the samples from the bulk cooling experiments were estimated by means of the X-ray diffraction (XRD) and the DSC method. It was found that the results from the DSC cooling and bulk cooling experiments are in good agreement. The continuous cooling transformation (CCT) diagram of the blast furnace slag was constructed according to crystallization kinetic model and experimental data. The obtained CCT diagram characterizes with two crystallization noses at different temperature ranges.

Gan, Lei; Zhang, Chunxia; Shangguan, Fangqin; Li, Xiuping

2012-06-01

184

Comparison of CO2 emission between COREX and blast furnace iron-making system.  

Science.gov (United States)

Steel works faced increasing demand to minimize the emission of GHGs. The CO2 emissions of COREX and blast furnace iron-making system were compared. It is point out that COREX contribute little to CO2 emission reduction. Comparing to conventional blast furnace iron-making system, direct CO2 emissions of COREX is higher. Considering the credits of export gases for power generation, the total CO2 emission of COREX have advantages only when the COREX is joined with high-efficiency generating units which efficiency is greater than 45% and CO2 emission factor of the grid is higher than 0.9 kgCO2/kWh. PMID:25084406

Hu, Changqing; Han, Xiaowei; Li, Zhihong; Zhang, Chunxia

2009-01-01

185

HBI production through coal-based direct reduction and its application in blast furnace  

Energy Technology Data Exchange (ETDEWEB)

In order to reduce CO{sub 2} emission and cope with the shortage of agglomerated ore due to the use of low-grade iron ore for a sintering process, which are key issues in the ironmaking field, it was proved that direct reduced iron can be manufactured using comparatively cheap fine iron ore and coal, or steel mill waste as the raw material. By using coal-based direct reduced iron, hot briquetted iron (HBI) which has sufficient strength for blast furnace use was manufactured in the demonstration plant. The use of this HBI in the blast furnace could contribute to reduce CO{sub 2} emission and dealing with the shortage of agglomerated ore.

Tanaka, H.; Harada, T. [Kobe Steel Ltd., Tokyo (Japan). Iron Unit Division

2006-12-15

186

Numerical simulation of flow in the raceway of blast furnace with heavy oil combustion  

Energy Technology Data Exchange (ETDEWEB)

The present study is to simulate the flow and combustion in the raceway of an industrial blast furnace with heavy oil as an injection fuel. The raceway shape is estimated from the force balance. Different geometry models have been used in order to find a suitable model which allows appropriate solution for the flow. The velocity vector plot, pressure, turbulent kinetic energy, and temperature distributions have been given. Predictions provide some insight into the flow mechanisms in the blast furnace and some useful information of engineering interests. Results show that there appear a recirculation zone located in the up-left region outside the raceway and a vortex below the raceway, and that the main flow moves upwards to the outlet. The flame penetrates into the raceway about two-fifth of its depth. (orig.) 15 refs.

Xia, Jiliang; Ahokainen, T.; Jokilaakso, A.; Mannila, P.; Haerkki, J.

1998-12-31

187

The influence of the blast furnace slag replacement on chloride penetration in concrete  

Directory of Open Access Journals (Sweden)

Full Text Available  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 investigating 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. 

Juan Lizarazo Marriaga

2011-05-01

188

Analyses on blast furnace raceway formation by micro wave reflection gunned through tuyere  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace raceway formation under the intensive coal injection by measurement of microwave reflection gunned through a tuyere is discussed. As the flow rate of coke as the momentum of coke into raceway decreases by combustion of coal injected into tuyeres, the depth of raceway defined as the maximum position of microwave reflection is easy to contract. It is expected that this new technology could detect the raceway collapse phenomena in short time and that the stability of raceway in coal injection is different from that in all coke operation. Finally the paper ends by summarizing the effect of raceway formation on unsteady phenomena forcing functional disorder on blast furnace performance of burden distribution for high productivity performance.

Matsui, Y.; Yamaguchi, Y.; Sawayama, M.; Kitano, S.; Nagai, N.; Imai, T. [Kobe Steel Ltd., Kakogawa (Japan). R& amp; D Lab.

2006-12-15

189

Analyses on blast furnace raceway formation by micro wave reflection gunned through tuyere  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace raceway formation under the intensive coal injection by measurement of micro wave reflection gunned through a tuyere is discussed. As the flow rate of coke as the momentum of coke into raceway decreases by combustion of coal injected into tuyeres, the depth of raceway defined as the maximum position of micro wave reflection is easy to contract. It is expected that this new technology could detect the raceway collapse phenomena in short time and that the stability of raceway in coal injection is different from that in all coke operation. Finally the paper ends by summarizing the effect of raceway formation on unsteady phenomena forcing functional disorder on blast furnace performance of burden distribution for high productivity performance.

Matsui, Y.; Yamaguchi, Y.; Sawayama, M.; Kitano, S.; Nagai, N.; Imai, T. [Kobe Steel Ltd., Hyogo (Japan). R& amp; D Labs.

2005-07-01

190

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.

191

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

Directory of Open Access Journals (Sweden)

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.

Babich, A. I.

2002-08-01

192

Effect of coke strength after reaction (CSR) on blast furnace performance  

Energy Technology Data Exchange (ETDEWEB)

This paper is divided into two parts: a) review of factors affecting CSR and the influence of CSR on blast furnace performance and b) relationship of CSR to cold strength properties and incorporation of coke properties for development of a new CSR prediction model that takes into account hardness (abrasion index), carbon form (gasification reactivity), and coke ash chemistry (catalysts for gasification). 95 refs., 5 figs., 3 tabs.

Best, M.H.; Burgo, J.A.; Valia, H. [United States Steel Corporation, Monroeville, PA (United States)

2002-07-01

193

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.)

194

Chloride-binding effect of blast furnace slag in cement pastes containing added chlorides  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Corrosion of rebar in concrete is commonly associated with, and to a large degree influenced by, the free chloride concentration in the pore water. It is standard industry practice to add various mineral admixtures such as pulverised fuel ash (PFA), or fly ash, ground granulated blast furnace slag (GGBS) and silica fume (SF), to concrete mixtures to increase the corrosion resistance of the reinforcement in the matrix and its subsequent design life span. Various investigations have re...

Potgieter, J. H.; Delport, D. J.; Verryn, Sabine Marie Charlotte; Potgieter-vermaak, S. S.

2011-01-01

195

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

196

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...

197

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 coa 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

198

A Mechanism Model for Raceway Formation and Variation in a Blast Furnace  

Science.gov (United States)

In this article, a previous mechanical model is extended to predict raceway penetration in a blast furnace (BF) and to dynamically illustrate how raceway penetration varies over time after the blast velocity varies based on Newton's second law. The model is validated by industrial measurements, and more precise predictions have been obtained using the present model. Moreover, the effects of combustion reactions on the raceway shape and size are taken into account in the present model. The mechanism for raceway formation and variation revealed by the present model is as follows: Fast movements of packed bed above a raceway roof due to blast blowing rate variation make raceway size vary rapidly and form its prototype; combustion reactions modify raceway size and shape, and they maintain its stability.

Guo, Jing; Cheng, Shusen; Zhao, Hongbo; Pan, Hongwei; Du, Pengyu; Teng, Zhaojie

2013-06-01

199

Strategic implications of and results from high rates of natural gas injection into the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

This review of high-rate fuel injection practices shows that some elements of practice and furnace performance depend on the type and amount of fuel injected while others do not. Natural gas injection provides the highest replacement ratios and requires the highest amount of oxygen enrichment because of its high hydrogen content. Large-size furnaces injecting coal achieve higher replacement ratios and productivities than do medium-sized furnaces, to a large extent, because they are better equipped and operate at higher blast temperatures and pressures. Furnaces injecting coal at high rates suffer permeability losses, and could require coinjected fuels or burden metallics in addition to achieving high productivities. These findings suggest that high-rate coal injection may be better suited for large furnaces that can be baseloaded and operated at low or medium productivities, and that natural gas injection is the preferred technology for furnaces that must respond to changing demand and must operate at medium to high productivities. With respect to the strategy of which fuel and how much to inject, the answer will depend upon the individual company and the value and the need for higher productivity when the market demand is higher. Natural gas provides a more assured way of coping with the inherent cyclicality of the steel industry.

Agarwal, J.C.; Brown, F.C.; Chin, D.L.; Stevens, G.S. [Charles River Associates, Inc., Boston, MA (United States); Smith, D.M. [Gas Research Inst., Chicago, IL (United States)

1996-12-31

200

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

 
 
 
 
201

Sideways tuyere probe for measuring the raceway region in a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

in the recent low-Si operation in a blast furnace, it is important to control, for reducing the content of Si in the molten iron, the flow, components and temperature distribution of the gas and the melt in the dropping zone at the raceway and its vicinity. In most of the conventional zondes which measure the raceway region, the area of measurement is limited within the raceway, and the items of measurement are only the sampling of the gas and the dust. Kawasaki Steel Corp. developed a zonde which can measure the raceway region, furnace core region and the region between the raceways, and named the unit ''Sideway tuyere probe zonde''. This report compares the features of the zonde with the conventional ones; the results of measurement is described on the distribution of Si in the molten iron in the vicinity of the blast furnace raceway, and the behavior of the pulverized coal in the actual furnace. 6 refs., 4 figs., 1 tab.

Takeda, Kanji; Taguchi, Seiji; Nakai, Toshikazu; kato, Haruo (Kawasaki Steel Corp., Tokyo (Japan))

1989-04-20

202

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

203

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

Energy Technology Data Exchange (ETDEWEB)

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 characteristics, 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 CO{sub 2} was conducted under isothermal conditions at 1050{sup o}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.

Maria de Lourdes Ilha Gomes; Eduardo Osorio; Antonio Cezar Faria Vilela [Federal University of Rio Grande do Sul - UFRGS, Porto Alegre (Brazil). Iron and Steelmaking Research Group/LASID

2006-07-01

204

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

Directory of Open Access Journals (Sweden)

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 degreesC 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.

Gomes Maria de Lourdes Ilha

2006-01-01

205

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2006-03-01

206

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

207

Numerical study of gas-solid flow in the raceway of a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a numerical study of gas-solid flow in a blast furnace raceway using a 2D slot cold model. Numerical experiments are conducted by combining the discrete element method for the solid phase with computational fluid dynamics for the gas phase. The motion of particles caused by lateral gas blasting under conditions similar to that in the blast furnace process is examined at a particle scale. Combustion and associated solids movement around the raceway are simulated by extraction of particles from the bottom of the bed. The effect of bed height or solid pressure is considered by imposing a downward force on the top layers of particles in the bed. It is shown that depending on the gas velocity, the bed can transit from a fixed bed to a fluidized bed or vice versa. Two zones can be identified in such a bed: a stagnant zone in which the particles remain at their initial positions, and a moving zone in which particles can move in various flow patterns. In particular, if the gas velocity is in a certain range, the moving zone is formed just in front of the gas inlet, giving the so-called raceway in which the particles can circulate. The effects of gas velocity, solid pressure and solid extraction are quantified. The fundamentals governing the gas-solid flow and the formation mechanisms of a raceway are discussed in terms of particle-particle and particle-fluid interaction forces. (orig.)

Feng, Y.Q.; Pinson, D.; Yu, A.B. [School of Materials Science and Engineering, Univ. of New South Wales, Sydney (Australia); Chew, S.J.; Zulli, P. [Steel Research Labs., BHP Steel, Port Kembla (Australia)

2003-09-01

208

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)

209

Effect of hot reducing gas (HRG) injection on blast furnace operational parameters: theoretical investigation  

Energy Technology Data Exchange (ETDEWEB)

The injection rate of fossil fuels in the blast furnace is limited because of a drop in the flame temperature in the raceway as well as problems in deadman region and the cohesive zone owing to the unburnt char. An alternative option for coke saving, a clean deadman as well as increase in blast furnace productivity is injection of hot reducing gases (HRG) which are produced by low grade coal gasification or top gas recycling after CO{sub 2} and N{sub 2} removal. Calculations using a mathematical model show that HRG injection at higher temperature is desirable. Hot reducing gas injection is possible up to 300 Nm{sup 3} thm{sup -1}, above which the top gas temperature shoots up beyond practical limits. Furthermore, it also shows that if the flame temperature is maintained constant by varying steam and oxygen injection, the productivity is increased by 16% and coke rate is reduced by 84 kg thm{sup -1} with the replacement ratio of 1.4 kg coke/kg gasified coal at 300 Nm{sup 3}/thm of HRG injection. It was also observed that the complete replacement of pulverised coal (PC) injection with HRG injection is more effective over the coinjection of PC and HRG in terms of coke rate saving. However, oxygen enrichment is possible up to 75% with the coinjection of HRG and PC, with a resultant of rise in productivity. Injection of HRG in the form of top gas (blast furnace gas) is more effective over the injection of HRG generated from coal gasification. The productivity is increased by 25% and coke rate is reduced by 83 kg thm{sup -1} with the replacement ratio of 1.7 kg coke/kg HRG at 250 Nm{sup 3} thm{sup -1} of HRG injected from top gas.

Desai, B.; Ramna, R.V.; Sathaye, J.M. [Tata Steel, Burmamines (India)

2008-01-15

210

Bosh slag chemistry control for high PCR and low slag volume blast furnace operation  

Energy Technology Data Exchange (ETDEWEB)

For the high pulverized-coal ratio (PCR) operation in the blast furnace, the slag volume should be minimized to secure good gas/liquid permeability in the low part of the blast furnace. As a measure of slag volume reduction, the MgO content in the sinter has been reduced to the level of 5%. As the slag volume is reduced, the chemistry of slags formed is expected to be changed. Using the tuyere probing technique in the field trials, the effects of slag volume reduction on the slag chemistry was studied. Based upon the analysis of the field trial data as well as laboratory experiment results, it is elucidated that the enhanced gas/liquid permeability is attributed not only to the slag volume reduction but also to the decrease of bosh slag viscosity. By lowering MgO content in the sinter, the bosh slag viscosity can be effectively decreased leading to a stable high PCR/low slag volume operation of the blast furnace. (orig.) [German] Bei hohen Kohlenstaub-Einblasraten sollte die Schlackenmenge minimiert werden, um eine gute Durchgasung im unteren Teil des Hochofens zu gewaehrleisten. Bei Verringerung der Schlackenmenge wird eine Aenderung der Schlackenzusammensetzung erwartet. In Betriebsversuchen wurde der Einfluss der Schlackenmengenreduktion auf die Schlackenzusammensetzung durch Probenahmen durch die Blasformen untersucht. Gleichzeitig mit der Verringerung der Schlackenmenge wurde der Gehalt an MgO im Sinter auf rund 5% gesenkt. Auf Basis dieser Versuchsergebnisse und weiterer Labormessungen wird deutlich, dass die verbesserte Gas-/Schmelzdurchlaessigkeit nicht nur auf die Verminderung der Schlackenmenge, sondern auch auf eine geringere Viskositaet der Rastschlacke zurueckzufuehren ist. Durch Absenken des MgO-Gehaltes im Sinter kann die Viskositaet der Rastschlacke deutlich vermindert werden, was zu einer stabilen Betriebsweise bei hohen Kohlenstaub-Einblasraten und geringen Schlackenmengen fuehrt. (orig.)

Yi, S.H. [Technical Research Labs., POSCO, Pohang (Korea); Yi, S. [Dept. of Materials Science and Metallurgy, Kyungpook National Univ., Daegu (Korea)

2003-07-01

211

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

212

Operating experiences with Corex and blast furnace at JSW Steel Ltd  

Energy Technology Data Exchange (ETDEWEB)

JSW Steel Ltd is an integrated steel plant of 3.8 mtpa capacity, with two Corex and two blast furnace (BF) units for producing hot metal. It has started its integrated steel plant operation with Corex ironmaking technology and then synergised with the conventional BF ironmaking during plant expansion. Both these ironmaking furnaces are unique in nature, and have different operation philosophies. The performances of these units depend on the raw material charged, operational philosophies, maintenance, etc., and have their own advantages and disadvantages. This paper brings out the comparison between these ironmaking processes through the usage of raw material inputs, plant operation, maintenance, quality of hot metal and byproducts. This paper also highlights the benefits due to synergistic combination of Corex and BF in an integrated steel plant.

Kumar, P. Prachethan; Gupta, P.K.; Ranjan, M.K.

2008-05-15

213

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

Energy Technology Data Exchange (ETDEWEB)

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.

Dr. Chenn Zhou

2008-10-15

214

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-12-31

215

Study on the early warning mechanism for the security of blast furnace hearths  

Science.gov (United States)

The campaign life of blast furnace (BF) hearths has become the limiting factor for safety and high efficiency production of modern BFs. However, the early warning mechanism of hearth security has not been clear. In this article, based on heat transfer calculations, heat flux and erosion monitoring, the features of heat flux and erosion were analyzed and compared among different types of hearths. The primary detecting elements, mathematical models, evaluating standards, and warning methods were discussed. A novel early warning mechanism with the three-level quantificational standards was proposed for BF hearth security.

Zhao, Hong-bo; Huo, Shou-feng; Cheng, Shu-sen

2013-04-01

216

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

Science.gov (United States)

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.

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

2013-07-01

217

Evolution of the specific fuel consumption rate in a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Analyzes factors that influence operation of a blast furnace and its productivity. Effects of coke quality are analyzed: moisture content, ash content, chemical composition of ash from coke (silica content and its effects on silicon content in iron, content of potassium oxide, sodium oxide and iron oxide and their effects on coke compression strength after reaction with carbon dioxide), coke compression strength, coke wear, coke permeability to gases, coke grain size distribution. Fuels used for partial replacement of standard coke are evaluated. Use of coal dust and fuel oils is also discussed. 17 refs.

Sabela, W.; Konstanciak, A.; Stanicki, S. (Politechnika Czestochowska (Poland))

1993-03-01

218

Thermodynamic modelling of the injection of waste products into a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to investigate the possibility to use blast furnaces for recycling of household and industrial wastes. In this respect, recycling conditions and requirements to utilize waste products are considered. The structure of waste products allowable for recycling in the blast furnace has been studied. Their behaviour is simulated at higher temperatures both in the presence (gasification, combustion) and in the absence (pyrolysis) of reactive gases. The possibility of formation of different components and their maximal concentrations, including dioxins and furans, are predicted. The results obtained prove not only the possibility, but highly recommend to use blast furnaces for the recycling of waste products, particularly plastics and other materials with high contents of carbon and hydrogen. This method guarantees not only the destruction but also the maximal effective use of the above-mentioned chemical components leading to the formation of ecologically safe products. One of the main problems in the recycling of waste products by thermal decomposition is the formation of dioxins and furans. However, the investigations conducted show that concentrations of dioxins and furans in the blast-furnace gas do not exceed the allowed concentration limits. (orig.) [German] Das Ziel dieser Arbeit ist die Untersuchung der Nutzung von Hochoefen zur Verwertung von Haushalts- und Produktionsabfaellen. Es wurden die Recyclingbedingungen und die Anforderungen an die zu verwertenden Abfaelle betrachtet. Insbesondere wurde die Zusammensetzung der fuer das Recycling im Hochofen geeigneten Abfaelle angegeben. Ihr Verhalten im Verlauf der thermischen Zersetzung sowohl bei der Anwesenheit (Vergasung, Verbrennung), als auch bei der Abwesenheit (Pyrolyse) von reaktiven Gasen wurde modelliert und die Wahrscheinlichkeit der Entstehung und die maximalen Konzentrationen der erhaltenen Recyclingprodukte, u.a. Dioxine und Furane, wurde prognostiziert. Die vorliegenden Ergebnisse beweisen nicht nur die Moeglichkeit, sondern auch die besondere Eignung von Hochoefen zur Verwertung der Abfaelle, vor allem von Kunststoffen und anderen Stoffen mit erhoehten Kohlenstoff- und Wasserstoffgehalten. Diese Methode garantiert nicht nur die Zersetzung, sondern auch die maximale Ausnutzung der Komponenten bei der Gewinnung umweltfreundlicher Produkte. Eines der wichtigsten Probleme beim Recycling von Abfaellen auf thermischem Weg ist die Bildung von Dioxinen und Furanen. Die durchgefuehrten Versuche sprechen jedoch dafuer, dass die Konzentrationen von Dioxinen und Furanen im Gichtgas maximal zulaessige Werte nicht ueberschreiten. (orig.)

Korobov, D. [Inst. fuer Energieverfahrenstechnik und Chemieingenieurwesen, TU Bergakademie Freiberg (Germany); Yusfin, Y.S. [Moscow State Inst. of Steel and Alloys, Technological Univ., Dept. of Thermal Ore Processing, Moscow (Russian Federation); Janke, D. [TU Bergakademie Freiberg, Inst. fuer Eisen- und Stahltechnologie, Freiberg (Germany)

2003-07-01

219

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)

220

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2010-01-01

 
 
 
 
221

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

Directory of Open Access Journals (Sweden)

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.

Carrasco, M. F.

2003-12-01

222

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

Science.gov (United States)

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.

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

2014-09-01

223

A critical appraisal of the present status of smelting reduction - Part 1. From blast furnace to Corex  

Energy Technology Data Exchange (ETDEWEB)

Developments in blast furnace technology have ensured its unchallenged superiority for bulk production of hot metal. However, alternative methods of making molten iron have come into the fray under the generic name of 'smelting reduction' to produce smaller quantities of hot metal, predominantly for use in EAF steelmaking in mini-mills by reducing iron ore - preferably fine, low-grade material using non-coking coal. Part 1 of this two part series highlights the success of the blast furnace in fighting off competition and examines the first commercial alternative to the blast furnace, the Corex process. In Part 2 in the Jul/August issue, other SR processes close to commercialisation are scrutinised. 3 figs., 4 tabs.

Chatterjee, Amit [Tata Steel, Jamshedpur (India)

2005-05-15

224

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

Science.gov (United States)

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.

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

2014-11-01

225

A study of the behaviour of coal injected into the blast furnace  

Energy Technology Data Exchange (ETDEWEB)

A two part experimental study of coal injection into the iron blast furnace is reported. In the first part, a high-pressure, electrically-heated wire-mesh reactor is used to simulate conditions experienced by coal particles in the tuyere and raceway regions of a commercial furnace. Measurements at 3 bar and 1600{sup o}C, in 25% O{sub 2}, indicate that the extent of coal conversion is modest in the short times available (order of 20 ms) and that complete coal burn-out is dependent on exposure to CO{sub 2} rich gases in the raceway of the furnace for 10 or more seconds. In the second part, both Size Exclusion Chromatography and Fourier-Transform Raman Spectroscopy are being applied to the study of dusts recovered from the gas cleaning plants of commercial furnaces. Preliminary results suggest that both techniques show promise for differentiating between the various types of carbon present in the dusts, thereby providing a degree of early warning of poor injectant coal combustion in the raceway. 8 refs., 15 figs.

S. Dong; L. Wu; N.P.M. Paterson; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering

2006-07-01

226

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

Science.gov (United States)

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.

Harvey, Jean-Philippe; Gheribi, Aïmen E.

2013-12-01

227

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)

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.

D. Noskievi?ová

2009-10-01

228

Continual Measuring of Local Stress Values on Shell of the Blast Furnace Hearth and of Total Shell Expansion  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with installation of strain gauges on the external surface of the blast furnace shell in two rows, whereas there will be defi ned 8 measuring points in every row. The fi nal result is evaluation of data obtained during up to 45 days of the operation. In this papers are commentary and discussions to measured time behaviours. The main purpose of this measuring was investigation of impact of salamander on blast furnace shell expansion after its lay off , cooling and next starting of operation.

P. Bigoš

2012-01-01

229

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

230

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

231

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)

232

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

233

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

234

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

Science.gov (United States)

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.

Saxén, Henrik

2014-08-01

235

A three-dimensional numerical study of the combustion of coal blends in blast furnace  

Energy Technology Data Exchange (ETDEWEB)

The practice of blending coals for pulverized coal combustion is widely used in ironmaking blast furnace. It is desirable to characterize the combustion behaviour of coal blends and their component coals. A three-dimensional numerical model is described to simulate the flow and combustion of binary coal blends under simplified blast furnace conditions. The model is validated against the experimental results from a pilot-scale combustion test rig for a range of conditions, which features an inclined co-axial lance. The overall performance of coal blend and the individual behaviours of their component coals are analysed, with special reference to the influences of particle size and coal type. The synergistic effect of coal blending on overall burnout is examined. The results show that the interactions between component coals, in terms of particle temperature and volatile content, are responsible for the synergistic effect. Such synergistic effect can be optimized by adjusting the blending fraction. The model provides an effective tool for the design of coal blends. 21 refs., 9 figs., 3 tabs.

Y.S. Shen; B.Y. Guo; A.B. Yu; P. Zulli [University of New South Wales, Sydney, NSW (Australia). Lab. for Simulation and Modelling of Particulate Systems

2009-02-15

236

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

Directory of Open Access Journals (Sweden)

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.

El-Hussiny N.A.

2010-01-01

237

Computational fluid dynamics study of pulverized coal combustion in blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

In this work, a numerical model is used to study the flow and coal combustion along the coal plume in a large-scale setting simulating the lance-blowpipe-tuyere-raceway region of a blast furnace. The model formulation is validated against the measurements in terms of burnout for both low and high volatile coals. The typical phenomena related to coal combustion along the coal plume are simulated and analyzed. The effects of some operational parameters on combustion behavior are also investigated. The results indicate that oxygen as a cooling gas gives a higher coal burnout than methane and air. The underlying mechanism of coal combustion is explored. It is shown that under the conditions examined, coal burnout strongly depends on the availability of oxygen and residence time. Moreover, the influences of two related issues, i.e. the treatment of volatile matter (VM) and geometric setting in modeling, are investigated. The results show that the predictions of final burnouts using three different VM treatments are just slightly different, but all comparable to the measurements. However, the influence of the geometric setting is not negligible when numerically examining the combustion of pulverized coal under blast furnace conditions.

Shen, Y.S.; Maldonado, D.; Guo, B.Y.; Yu, A.B.; Austin, P.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia). School of Materials Science & Engineering

2009-12-15

238

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

Science.gov (United States)

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.

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

2014-10-01

239

A thermodynamic study of silicon containing gas around a blast furnace raceway  

Energy Technology Data Exchange (ETDEWEB)

The equilibrium conditions for silicon transfer from ash to the liquid metal phase via SiO gas have been discussed by several authors. However, no published calculations have been found using the most modern thermodynamic models available. Since there are major differences in the results of calculations using different thermodynamic models and the models are continuously being improved, new equilibrium calculations on SiO and SiS gas formation have been performed using the recently developed models. Different ingoing compositions of coke ash, coal powder ash and blast air were used in the calculations. The compositions chosen represent blast furnace no. 3 at SSAB in Lulea, Sweden. Temperature was found to be the major factor influencing the equilibrium silicon level in the gas phase. At low temperatures (below 1600{sup o}C the total gas pressure was also seen to influence the silicon content in the gas phase. The main reason for this is that below 1600{sup o}C, the amount of liquid slag at equilibrium increases with the total gas pressure. Liquid slag contains large amounts of silica that then can not be found in the gas phase. Higher carbon activity is usually expected to result in higher SiO gas levels in the blast furnace. The equilibrium calculations show that increased carbon activity increases the amount of silicon in the gas phase at temperatures up to about 1600{sup o}C, but that at higher temperatures SiC is formed that decreases the equilibrium silicon level in the gas phase.

Gustavsson, J.; Andersson, A.M.T.; Jonsson, P.G. [Royal Institute of Technology, Stockholm (Sweden)

2005-07-01

240

Modeling coal combustion behavior in an ironmaking blast furnace raceway: model development and applications  

Energy Technology Data Exchange (ETDEWEB)

A numerical model has been developed and validated for the investigation of coal combustion phenomena under blast furnace operating conditions. The model is fully three-dimensional, with a broad capacity to analyze significant operational and equipment design changes. The model was used in a number of studies, including: Effect of cooling gas type in coaxial lance arrangements. It was found that oxygen cooling improves coal burnout by 7% compared with natural gas cooling under conditions that have the same amount of oxygen enrichment in the hot blast. Effect of coal particle size distribution. It was found that during two similar periods of operation at Port Kembla's BF6, a difference in PCI capability could be attributed to the difference in coal size distribution. Effect of longer tuyeres. Longer tuyeres were installed at Port Kembla's BF5, leading to its reline scheduled for March 2009. The model predicted an increase in blast velocity at the tuyere nose due to the combustion of volatiles within the tuyere, with implications for tuyere pressure drop and PCI capability. Effect of lance tip geometry. A number of alternate designs were studied, with the best-performing designs promoting the dispersion of the coal particles. It was also found that the base case design promoted size segregation of the coal particles, forcing smaller coal particles to one side of the plume, leaving larger coal particles on the other side. 11 refs., 15 figs., 4 tabs.

Maldonado, D.; Austin, P.R.; Zulli, P.; Guo B. [BlueScope Steel Research Laboratories, Port Kembla, NSW (Australia)

2009-03-15

 
 
 
 
241

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

Science.gov (United States)

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.

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

2014-10-01

242

Distribution of the blast furnace gas in V and M of Brazil during the reduction of production; Distribuicao de GAF na V e M do Brasil durante a reducao de producao  

Energy Technology Data Exchange (ETDEWEB)

V e M do Brasil is an integrated steel mill with the production of seamless steel pipe. The manufacture process comprises two charcoal blast furnaces that have blast furnace gas as a by-product. The use of natural gas is complementary to the blast furnace gas in the mills. The appropriate planning of these intakes during the crisis had as premise the best use of blast furnace gas and minimizing the use of natural gas. With this planning, it was possible to optimize the use of blast furnace gas reducing 8% of natural gas cost. (author)

Lana, Camila Soares; Silva, Ricardo Junqueira; Soares, Lis Nunes; Valentim, Rodrigo Freitas [V e M do Brasil S.A., Belo Horizonte, MG (Brazil)

2010-07-01

243

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...

244

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

Directory of Open Access Journals (Sweden)

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 granulated 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(OH2 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(OH2 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.

Ali Nazari

2011-09-01

245

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

Ali, Nazari; Shadi, Riahi.

246

Coal combustion under conditions of blast furnace injection. [Quarterly] technical report, 1 December 1993--28 February 1994  

Energy Technology Data Exchange (ETDEWEB)

A potentially new use for Illinois coal is its use as a fuel injected into a blast furnace to produce molten iron as the first step in steel production. Because of its increasing cost and decreasing availability, metallurgical coke is now being replaced by coal injected at the tuyere area of the furnace where the blast air enters. The purpose of this study is to evaluate the combustion of coal during the blast furnace injection process and to delineate the optimum properties of the feed coal. This proposal is a follow-up to one funded for the 1992--1993 period. It is intended to complete the study already underway with the Armco Inc. Steel Company and to initiate a new cooperative study along somewhat similar lines with the Inland Steel Company. The results of this study will lead to the development of a testing and evaluation protocol that will give a unique and much needed understanding of the behavior of coal in the injection process and prove the potential of Illinois coals for such use. During this quarter a sample of the feed coal that is being used for injection into the No. 7 Blast Furnace of Inland Steel has been analyzed petrographically and compared to both the Herrin No. 6 coal and Armco feed coal. Additional characterization is underway and an advanced program of pyrolysis and reactivity testing has been initiated.

Crelling, J.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology

1994-06-01

247

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

Ali, Nazari; Shadi, Riahi.

2011-09-01

248

Microstructure and Properties of Zircon-Added Carbon Refractories for Blast Furnace  

Science.gov (United States)

Microstructure and properties of zircon-added carbon refractory specimens for blast furnace (BF) were investigated with the aid of X-ray diffraction (XRD), a scanning electron microscope (SEM), energy-dispersive X-ray, mercury porosimetry, and a laser thermal conductivity (TC) meter. Additives could influence the matrix structures and improve the properties of specimens. With the increase of zircon powder content, the amount of SiC whiskers formed increased and their aspect ratio became larger, and the SiC whiskers tended to be distributed homogeneously. Zircon powder additions decreased the mean pore diameter and increased <1- ?m pore volume by filling in pores via SiC, improved the TC and the cold crushing strength (CCS) due to the in-situ formation of the more well-developed SiC whiskers with high TC, and significantly reduced the molten iron attack to carbon specimens.

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

2012-11-01

249

Fe-Si droplets associated with graphite on blast furnace coke  

Science.gov (United States)

Fe-Si droplets on the surface of blast furnace (BF) coke from 25 to 50 cm at the tuyere level are mostly composed of Fe3Si, which has various shapes (round, elongated, and irregular) and penetration degrees into the BF coke matrix. The shapes and penetration degrees may depend on the saturation of molten iron by silicon during interaction with the coke matrix. The droplets are covered by a tiny shell of carbon. Graphite observed inside the droplets can be divided into two categories: well-formed tabular crystals with relatively large size and flakes with structures similar as those in cast iron. The textures of the droplets reflect composition, interaction with the coke matrix, and cooling conditions.

Gornostayev, Stanislav S.; Fabritius, Timo M. J.; Kerkkonen, Olavi; Härkki, Jouko J.

2012-06-01

250

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

Science.gov (United States)

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

Guerrero, A; Goñi, S

2002-01-01

251

Cooperation between Czechoslovakia and the USSR in the field of intensification of blast furnace coke production  

Energy Technology Data Exchange (ETDEWEB)

Briefly describes a 1986-87 contract that involved Czechoslovak signatories in developing technical parameters for coking Soviet coal. Coal samples were first analyzed in laboratory, then 20 t of coal were coked in a 400 kg pilot plant. Next, larger scale trials were carried out using 3000 t of coal imported from the USSR. Results confirmed feasibility of the process. The Soviet UCHIN research institute looked at the possibility of pre-heating Czechoslovak coal charges. Joint trials using 3 charges taken from 2500 t of Czechoslovak coal were carried out. Results showed that pre-heating to 180-200 C gave good quality blast furnace coke, while increasing coke battery output by about 50%. This technique will be used in future Czechoslovak coking plants.

Kana, J.

1988-08-01

252

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2010-07-15

253

Observation and analysis of fluidisation and flooding phenomena in lower blast furnace by model experiments  

Energy Technology Data Exchange (ETDEWEB)

A study has been carried out on abnormal flow phenomenon in the lower blast furnace (BF) for the purpose of the determination of appropriate measures to realise higher productivity and higher pulverised coal injection rate. An experimental apparatus was erected and tests were conducted under simulated BF conditions. Observations of the flow behaviour of gas, liquid and solid particles at varied gas and liquid flowrates revealed that typically, flooding occurred only in the systems with large, heavy particles, whereas typically fluidisation took place only in the systems with very light particles. A diagram of gas flowrate at flooding point against that at fluidisation point was created based on the test results. A conclusion that it is flooding which could possibly occur in the lower BF could be reached by using this diagram.

Fu, L.C.; Bi, X.G.; Xiong, W.; Zhou, G.F. [Wuhan University of Science & Technology, Wuhan (China)

2008-08-15

254

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

Science.gov (United States)

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.

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

2014-10-01

255

Influence of additions of coal fly ash and quartz on hydrothermal solidification of blast furnace slag  

Energy Technology Data Exchange (ETDEWEB)

Blast furnace water-cooled slag (BFWS) has been solidified hydrothermally with tobermorite formation. The experimental results showed that the addition of fly ash and quartz was favorable to the formation of tobermorite, and the strength development of solidified body depended on both of the tobermorite formation and filling degree of formed tobermorite in the spaces between BFWS particles. The fly ash added appeared to have a higher reactivity than the quartz used during the initial hydrothermal processing due to the higher solubility of glassy phase in fly ash. The tobermorite formation seemed to be very sensitive to the fly ash content, e.g., the addition of fly ash 10-20 mass% was favorable to tobermorite formation, while the excessive addition of fly ash (> 20 mass%) appeared to impede the tobermorite formation. The excessive addition of quartz was also shown to exert a negative effect on the tobermorite formation, which causes strength deduction.

Jing, Z.; Jin, F.; Hashida, T.; Yamasaki, N.; Ishida, E.H. [Tohoku University, Miyagi (Japan). Graduate School for Environmental Studies

2008-07-15

256

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

Science.gov (United States)

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

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

2014-02-15

257

Heavy metals adsorption on blast furnace sludges; Adsorcion de metales pesados sobre lodos de horno alto  

Energy Technology Data Exchange (ETDEWEB)

Most of industrial liquid effluents have high contents of heavy metals. The recovery of these metals is environmental and economically interesting. In this work we study the use of sludge, a by-product of the steel industry, as an adsorbent for the removal of heavy metals from liquid effluents. The adsorption of Pb``2+, Zn``2+, Cd``2+, Cu``2+ and Cr``3+ on the sludge was investigated by determination of adsorption isotherms. The effect of time, equilibrium temperature and concentration of metal solution on sludge adsorption efficiency was evaluated. The adsorption process was analysed using the theories of Freundlich and Langumuir and the thermodynamic values {Delta}G, {Delta}H and {Delta}S corresponding to each adsorption process were calculated. Blast furnace sludge was found to be an effective sorbent for Pb, Zn, Cd, Cu and Cr-ions within the range of ion concentrations employed. (Author) 5 refs.

Lopez-Delgado, A.; Perez, C.; Lopez, F.A. [Centro Nacional de Investigaciones Metalurgicas. CENIM. Madrid (Spain)

1998-10-01

258

Reactivity of brazilian coal, charcoal, imported coal and blends aiming to their injection into blast furnaces  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english For about 10 years the steel industry in Brazil has used pulverized coal injection (PCI) technology in the blast furnaces based on imported coals. In order to decrease the dependence on imported coals, Brazilian coal, which has limited use due to high ash content, was suggested to be mixed with impo [...] rted coal and charcoal. The aim was to examine the reactivity of the samples. The charcoal use in the steel industry contributes to the CO2 emission reduction, since it represents a renewable source of energy. The reactivity of the coals, charcoal and mixtures was evaluated through simultaneous thermal analyses. Results of this study are presented and discussed.

Janaína Gonçalves Maria da Silva, Machado; Eduardo, Osório; Antônio Cezar Faria, Vilela.

2010-09-01

259

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

Science.gov (United States)

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

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

2014-12-01

260

Experimental Studies on Concrete Replacing Fine Aggregate with Blast Furnace Slags  

Directory of Open Access Journals (Sweden)

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.

J. Selwyn Babu

2014-04-01

 
 
 
 
261

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 disscusion 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.

Recientemente se ha incorporado un valor del coeficiente de eficacia K para la escoria de horno alto en la norma europea EN 206-1:2000. Los valores propuestos en los grupos de trabajo eran muy diversos ya que en algunos casos sólo consideraban la resistencia mecánica para su determinación mientras que en otros se remarcaba la importancia de tener en cuenta, además, aspectos relativos a la durabilidad del hormigón con dicha adición. En el presente artículo se discuten las ventajas y desventajas de proponer unos valores del coeficiente de eficacia K más o menos conservadores. La conclusión final se resume con la propuesta de una recomendación lógica que consiste en trasladar a cada país la elección del coeficiente K para que pueda aplicarse a los hormigones empleados en su territorio; tales valores de K deberán ser seleccionados de acuerdo con la experiencia de cada uno de los países.

Sanjuán, M. A.

2011-06-01

262

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

Science.gov (United States)

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

Kim, Jung-Wook; Jung, Myung Chae

2011-01-01

263

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

Directory of Open Access Journals (Sweden)

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".

Babich, A.

2005-12-01

264

Introduction of low calorific value blast furnace gas firing system in  

Energy Technology Data Exchange (ETDEWEB)

Boiler no 6 of Power & Blowing Station (PBS) in Bhilai Steel Plant (BSP), India, commissioned in 1994, was designed for using pulverised coal for production of superheated steam at 40 ata. pressure and 450{sup o}C temperature with a maximum continuous rating of 150TPH. CO gas firing system was provided for flame support. A retrofit project was taken up to introduce high capacity Blast Furnace Gas (BFG) firing system in this boiler to replace pulverised coal firing. BF Gas which is generated as a by-product gas in the Blast Furnaces of Steel Plants does not burn easily because of its low calorific value (CV {approx}780 Kcal/Nm{sup 3}). To meet the technological requirements, a special burner design was developed for firing BF gas in large quantity in Boiler no.6. Six burners of identical design, each with a capacity to fire BF Gas at a rate of 10000 Nm{sup 3}/hr (total capacity: 60000 Nm{sup 3}/hr), were installed along with other accessories and equipment on Left and Right side walls of the boiler, retaining the original 12 nos. of composite burners on the boiler Front wall. The new BF gas firing system was commissioned successfully in March 2005 and the new BF gas combustion system is working well since then. Due to this development, pulverised coal (purchased fuel) firing in boiler no.6 is completely eliminated with (by-product) BF gas. This has resulted in significant economical and environmental benefits to the Bhilai Steel Plant, India. This paper describes the design features of the high capacity BF gas burner and the modifications incorporated in the boiler under the above retrofit project. 6 figs., 2 tabs.

M. Sen; P.K. Dubey; P.K. Tripathi; S.S.S. Murthy; R.C. Kulkarni [Steel Authority of India Limited, Ranchi (India). Thermal Engineering Group, Research & Development Centre for Iron and Steel (RDCIS)

2006-07-01

265

Pulverizing, drying and transporting system for injecting a pulverized fuel into a blast furnace  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a pulverizing, drying and transporting system for a puvlerized fuel of a blast furnace of the type having at least one hot stove for supplying hot blast air, said hot stove also providing hot stove exhaust gas. The system includes a pulverizing and drying unit for pulverizing lump raw fuel and drying the pulverized fuel. The hot stove gas is supplied to the pulverizing and drying unit. The hot stove exhaust gas dries the pulverized fuel and conveys it to a pulverized fuel collecting and separating device which separates the gas from the pulverized fuel. The line supplying the hot stove gas to the pulverizing and drying unit includes a heating device for selectively supplying additional heat to the hot stove exhaust gas. Moreover, the line for supplying the hot stove gas to the pulverizing and drying unit can include at least one of a temperature stabilizing device and a cooling device. The heating and cooling devices are controlled by a controller sensitive to the gas temperature at the outlet of the pulverizing and drying unit for maintaining the gas temperature at the outlet of the pulverizing and drying unit at a constant level. The temperature stabilizing device maintains the gas temperature at the outlet of the temperature stabilizing device at a designated level.

Tamura, S.; Motonaga, K.; Mizokawa, T.; Tanaka, K.; Kawashima, K.; Hiwatashi, T.; Sugahara, T.

1987-09-29

266

Influence of nut coke on iron ore sinter reducibility under simulated blast furnace conditions  

Energy Technology Data Exchange (ETDEWEB)

One of the most important factors to increase the economic efficiency of the blast furnace process is to reduced coke losses (undersieve product known as nut coke). In recent years there has been increased interest in mixing nut coke in the sinter layers. In order to clarify the influence of nut coke on sinter reducibility, sinter and sinter-nut coke mixtures were isothermally reduced with 30%CO-70%N{sub 2} at 1173-1523 K using a muffle furnace supported by an on-line gas analyser. Reflected light microscopy, scanning electron microscopy and X-ray technique were used to characterise the microstructure and the different phases developed in the original and reduced sinter. Sinter reduced without nut coke participation exhibited reduction retardation at elevated temperatures (>1373 K) while the presence of nut coke prevented such phenomena. The rate controlling mechanism of sinter and sinter-nut coke mixture was predicted from the correlation between apparent activation energy calculations, mathematical modelling derived from gas-solid reaction model and microstructure examination.

Mousa, E.A.; Senk, D.; Babich, A.; Gudenau, H.W.

2010-04-15

267

CFD modelling and analysis of pulverized coal injection in blast furnace: an overview  

Energy Technology Data Exchange (ETDEWEB)

In order to understand the complicated phenomena of pulverized coal injection (PCI) process in blast furnace (BF), several mathematical models have been developed by the UNSW and BSR cooperation. These models are featuring from coal combustion in a pilot-scale test rig, to coal combustion in a real BF, and then to coal/coke combustion in a real BF, respectively. This paper reviews these PCI models in aspects of model developments and model applicability. The model development is firstly discussed in terms of model formulation, their new features and geometry/regions considered. The model applicability is then discussed in terms of main findings followed by the model evaluation on their advantages and limitations. It is indicated that the three PCI models are all able to describe PCI operation qualitatively. The model of coal/coke combustion in a real BF is more reliable for simulating in-furnace phenomena of PCI operation qualitatively and quantitatively. Such model gives a more reliable burnout prediction over the raceway surface, which could better represent the amount of unburnt char entering the coke bed. These models are useful for understanding the flow-thermo-chemical behaviours and then optimising the PCI operation in practice. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Shen, Yansong; Yu, Aibing [Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales (UNSW), Sydney, NSW 2052 (Australia); Zulli, Paul [BlueScope Steel Research (BSR), P.O. Box 202, Port Kembla, NSW 2505 (Australia)

2011-05-15

268

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

269

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 t [...] opo 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. Abstract in english 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 furnac [...] e 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.

Ulysses Forastieri de, Matos; José Adilson de, Castro.

270

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)

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.

Ulysses Forastieri de Matos

2012-03-01

271

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 t [...] opo 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. Abstract in english 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 furnac [...] e 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.

Ulysses Forastieri de, Matos; José Adilson de, Castro.

2012-03-01

272

Compare pilot-scale and industry-scale models of pulverized coal combustion in an ironmaking blast furnace  

Science.gov (United States)

In order to understand the complex phenomena of pulverized coal injection (PCI) process in blast furnace (BF), mathematical models have been developed at different scales: pilot-scale model of coal combustion and industry-scale model (in-furnace model) of coal/coke combustion in a real BF respectively. This paper compares these PCI models in aspects of model developments and model capability. The model development is discussed in terms of model formulation, their new features and geometry/regions considered. The model capability is then discussed in terms of main findings followed by the model evaluation on their advantages and limitations. It is indicated that these PCI models are all able to describe PCI operation qualitatively. The in-furnace model is more reliable for simulating in-furnace phenomena of PCI operation qualitatively and quantitatively. These models are useful for understanding the flow-thermo-chemical behaviors and then optimizing the PCI operation in practice.

Shen, Yansong; Yu, Aibing; Zulli, Paul

2013-07-01

273

Silicon addition in charcoal blast furnaces. Part 1: pig iron/slag equilibrium; Incorporacao de silicio em altos-fornos a carvao vegetal. Parte 1: equilibrio gusa-escoria no cadinho  

Energy Technology Data Exchange (ETDEWEB)

Considering that the silicon content in the iron is sometime the unique thermal control used in blast furnaces, it has been decided to investigate such silicon transfer in charcoal blast furnaces. The results from five industrial furnaces have shown that also in charcoal operated furnaces have shown that also in charcoal operated furnaces such phenomena occurs, and the level of silicon oxidation depends on operational practices 7 refs., 7 figs.

Figueira, Renato Minelli; Castro, Luiz Fernando Andrade; Tavares, Roberto Parreiras; Fernandes, Antonio Alberto Grossi [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Metalurgica

1987-12-31

274

Mass and chemical composition optimization of blast furnaces slags; Otimizacao de peso e composicao quimica de escorias de altos-fornos  

Energy Technology Data Exchange (ETDEWEB)

The chemical composition of slags of charcoal and coke blast furnaces is optimized considering the quality constraints for the maximum efficiency of the process, specified by means of pseudo-ternary diagrams. Aiming the best chemical composition, mass balances were also developed to determine the minimum weight of slag that can be produced. The results were compared to the industrial data from Brazilian charcoal and coke blast furnaces and possible changes are suggested. (author). 5 refs., 8 figs., 2 tabs.

Tavares, Roberto P.; Castro, Luiz F.A. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenheria Metalurgica

1992-12-31

275

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'

276

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

277

Metal retention on pine bark and blast furnace slag--on-site experiment for treatment of low strength landfill leachate.  

Science.gov (United States)

Treatment of landfill leachate using blast furnace slag and pine bark as reactive sorbents was studied in an in situ column experiment at the Lilla Nyby landfill site in Eskilstuna, Sweden. The columns were filled with approximately 101 of each sorbent and leachate was supplied at three different flow rates during a period of 4 months. Samples of inflow and outflow were collected three times a week and were analyzed for physical and chemical parameters, including concentrations of some metals, and toxicity. It was found that pine bark removed metals more efficiently than did the blast furnace slags; that Zn was most efficiently retained in the filters and that both retention time and initial concentration played an important role in the sorption process. It was also observed that the pine bark column did not release COD. No toxicity of the untreated or the treated leachate was found with the test organisms and test responses used. PMID:17462882

Nehrenheim, Emma; Waara, Sylvia; Johansson Westholm, Lena

2008-03-01

278

Numerical investigation of gas flow through blast furnace shaft with designed layered structure of ore and coke burdens  

Energy Technology Data Exchange (ETDEWEB)

Detailed comments on governing equations and boundary conditions on which numerical results of gas flow in porous media should rely are presented. Numerical results are shown for the gas flow through a large blast furnace with designed layered structure of burdens. Not only the effects of radial and vertical distributions of resistance to flow but also the effects of different top profiles of burden, such as V-, M-shapes and V-shape with a side terrace, on the resultant gas flow are discussed in relation to the properties of burden, such as repose angle, particle size, voidage and different charging sequence. For the gas flow in a coaxial annulus bed, which is expected to appear in the lower part of blast furnace during a start-up or a blow-out operation, numerical predictions are compared with analytical ones based on a simple yet convenient gas flow model.

Qing, G.L.; Ma, L.; Zhang, X.S.; Zhou, J.L.; Kuwabara, M.

2010-10-15

279

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)

280

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

Energy Technology Data Exchange (ETDEWEB)

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)

Ryman, C. [MEFOS-Metallurgical Research Inst. AB, Lulea (Sweden); Lulea Univ. of Technology, Div. of Energy Engineering, Lulea (Sweden)]. E-mail: christer.ryman@mefos.se; Grip, C.-E. [SSAB Tunnplat AB, Lulea (Sweden); Lulea Univ. of Technology, Div. of Energy Engineering, Lulea (Sweden); Franck, P.-A. [CIT Industriell Energianalys AB, Chalmers teknikpark, Gothenburg (Sweden); Wikstrom, J.-O. [MEFOS-Metallurgical Research Inst. AB, Lulea (Sweden)

2005-07-01

 
 
 
 
281

Reactivity and conversion behaviour of Brazilian and imported coals, charcoal and blends in view of their injection into blast furnaces  

Energy Technology Data Exchange (ETDEWEB)

For about 10 years the steel industry in Brazil has been using pulverized coal injection (PCI) technology in blast furnaces based on imported coals. In order to decrease the dependence on imported coals, Brazilian coal which has limited use due to high ash content is suggested to be mixed with imported coal and charcoal. The aim of this study is to examine the reactivity and combustion behaviour of the mentioned materials. The use of charcoal in the Brazilian steel industry reduces the CO{sub 2} emissions, since it represents a renewable source of carbon. The reactivity of the coal, charcoal and mixtures is evaluated through TGA. To provide a useful insight into the practice of PCI in blast furnaces, experiments are carried out with a laboratory rig at RWTH Aachen University that simulates the behaviour of fines injected into the raceway. The results of this study are presented and discussed. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

Machado, J.G.M.S.; Osorio, E.; Vilela, A.C.F. [Iron and Steelmaking Research Group/LASID - Federal University of Rio Grande do Sul - UFRGS - Technology Center, Porto Alegre, RS (Brazil); Babich, A.; Senk, D.; Gudenau, H.W. [Institut fuer Eisenhuettenkunde/IEHK - RWTH Aachen (Germany)

2010-01-15

282

Influence of crucible drainage on the performance of a blast furnace; Influencia da drenagem do cadinho no desempenho do alto forno  

Energy Technology Data Exchange (ETDEWEB)

This paper shows the behaviour of the performance of a charcoal blast furnace, when the crucible volume was reduced and the drainage times was increased. Thus, the performance of the system became satisfactory, optimizing the permeability of the crucible and increasing the profit of the charcoal in the furnace. 6 refs., 9 figs., 1 tab.

Pereira, Felipe J.N. [Companhia de Acos Especiais Itabira (ACESITA), Itabira, MG (Brazil); Figueira, Renato M.; Tavares, Roberto P.; Castro, Luiz F.A. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenheria Metalurgica

1991-12-31

283

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

Directory of Open Access Journals (Sweden)

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.

Awang H.

2014-01-01

284

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

Science.gov (United States)

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

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

2010-05-15

285

Evaluation of blast furnace slag as basal media for eelgrass bed.  

Science.gov (United States)

Two types of blast furnace slag (BFS), granulated (GS) and air-cooled slag (ACS), were evaluated as basal media for eelgrass bed. Evaluation was done by comparing BFS samples with natural eelgrass sediment (NES) in terms of some physico-chemical characteristics and then, investigating growth of eelgrass both in BFS and NES. In terms of particle size, both BFS samples were within the range acceptable for growing eelgrass. However, compared with NES, low silt-clay content for ACS and lack of organic matter content for both BFS samples were found. Growth experiment showed that eelgrass can grow in both types of BFS, although growth rates in BFS samples shown by leaf elongation were slower than that in NES. The possible reasons for stunted growth in BFS were assumed to be lack of organic matter and release of some possible toxins from BFS. Reduction of sulfide content of BFS samples did not result to enhanced growth; though sulfide release was eliminated, release of Zn was greater than before treatment and concentration of that reached to alarming amounts. PMID:19150584

Hizon-Fradejas, Amelia B; Nakano, Yoichi; Nakai, Satoshi; Nishijima, Wataru; Okada, Mitsumasa

2009-07-30

286

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

Science.gov (United States)

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.

Zemskov, Serguey V.; Ahmad, Bilal; Copuroglu, Oguzhan; Vermolen, Fred J.

2013-02-01

287

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

Science.gov (United States)

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

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

2013-01-01

288

Chloride leaching from air pollution control residues solidified using ground granulated blast furnace slag.  

Science.gov (United States)

Ground granulated blast furnace slag (ggbs) has been used to solidify air pollution control (APC) residues obtained from a major UK energy-from-waste plant. Samples were prepared with ggbs additions between 10 and 50 wt% of total dry mass and water/solids ratios between 0.35 and 0.80. Consistence, setting time, compressive strength and leaching characteristics have been investigated. Results indicated that the highly alkaline nature of APC residues due to the presence of free lime can be used to activate ggbs hydration reactions. Increasing ggbs additions and reducing the water content resulted in increased compressive strengths, with 50 wt% ggbs samples having average 28 d strengths of 20.6 MPa. Leaching tests indicate low physical encapsulation and minimal chemical fixation of chloride in ggbs solidified APC residues. The results suggest that more than 50 wt% ggbs additions would be required to treat APC residues to meet the current waste acceptance criteria limits for chloride. PMID:18805564

Lampris, Christos; Stegemann, Julia A; Cheeseman, Christopher R

2008-11-01

289

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

Science.gov (United States)

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

Asaoka, Satoshi; Yamamoto, Tamiji

2010-04-01

290

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

291

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)atic test. (author)

292

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

293

Ultrasonic-Assisted Acid Leaching of Indium from Blast Furnace Sludge  

Science.gov (United States)

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.

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

2013-12-01

294

Effect of blast furnace slag addition to Portland cement for cationic exchange resins encapsulation  

International Nuclear Information System (INIS)

In the nuclear industry, cement-based materials are extensively used to encapsulate spent ion exchange resins (IERs) before their final disposal in a repository. It is well known that the cement has to be carefully selected to prevent any deleterious expansion of the solidified waste form, but the reasons for this possible expansion are not clearly established. This work aims at filling the gap. The swelling pressure of IERs is first investigated as a function of ions exchange and ionic strength. It is shown that pressures of a few tenths of MPa can be produced by decreases in the ionic strength of the bulk solution, or by ion exchanges (2Na+ instead of Ca2+, Na+ instead of K+). Then, the chemical evolution of cationic resins initially in the Na+ form is characterized in CEM I (Portland cement) and CEM III (Portland cement + blast furnace slag) cements at early age and an explanation is proposed for the better stability of CEM III material. (authors)

295

Quantitative description of void distributions i blast furnace raceway; Koro raceway no kukan kozo  

Energy Technology Data Exchange (ETDEWEB)

A void distribution in a blast furnace raceway significantly affects the results of numerical simulations for the raceway combustion zone. Despite its importance, technical difficulty in measuring this physical property had left a quantitative description out of reach. In the present paper, the direct ,measurement of raceway void distributions was attained in a three-dimensional cold model with the aid of laser sensors. Measured void fractions clarified the typical distribution pattern in a raceway, showing the inlet region with relatively high and constant void fractions (the gas core region) from the buyers tip to the middle part of the raceway, followed by the linear decrease of voidage toward the raceway boundary. The extent of the gas core region was used to achieve the non-dimensional representation for the axial void distribution, and was successfully estimated by the newly established correlation between a gas core length (DM), a tuyere diameter (DT) and a raceway factor (Rf), expressed by DM/DT = 0.963Rf{sup 0.546}. 20 refs., 12 figs., 1 tab.

Nozawa, K.; Kamijo, T.; Shimizu, M. [Kobe Steel, Ltd., Kobe (Japan)

1995-09-01

296

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

Science.gov (United States)

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.

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

2014-10-01

297

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

Science.gov (United States)

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.

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

2014-08-01

298

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.

299

Stabilization of chloro-organics using organophilic bentonite in a cement-blast furnace slag matrix.  

Science.gov (United States)

The application of cement-based stabilisation/solidification treatment to organic-containing wastes is made difficult by the adverse effect of organics on cement hydration. The use of organophilic clays as pre-solidification adsorbents of the organic compounds can reduce this problem because of the high adsorption power of these clays and their compatibility with the cementitious matrix. This work presents an investigation of the effect on hydration kinetics, physico-mechanical properties and leaching behaviour of cement-based solidified waste forms containing 2-chlorophenol and 1-chloronapthalene adsorbed on organophilic bentonites. These were prepared by cation exchange with benzyldimethyloctadecylammonium chloride and trimethyloctadecylammonium chloride. The binder was a 30% pozzolanic cement, 70% granulated blast furnace slag mixture. Several binder-to-bentonite ratios and different concentrations of the organics on the bentonite were used. Kinetics of hydration were studied by measurement of chemically bound water and by means of thermal and calorimetric analyses. Microstructure and other physico-mechanical properties of the solidified forms were studied by means of mercury intrusion porosimetry, scanning electron microscopy and unconfined compressive strength measurement. Leaching was checked by two different leaching tests: one dynamic, on monolithic samples, and the other static, on powdered samples. This study indicates that the incorporation of the organic-loaded bentonite in the binder matrix causes modifications in the hardened samples by altering cement hydration. The effects of the two organic contaminants are differentiated. PMID:11530921

Cioffi, R; Maffucci, L; Santoro, L; Glasser, F P

2001-01-01

300

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)

 
 
 
 
301

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.

302

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.

303

Cement with silica fume and granulated blast-furnace slag: strength behavior and hydration  

Directory of Open Access Journals (Sweden)

Full Text Available This paper analyses the influence of portland cement replacement by silica fume (up to 10% and/or granulated blast furnace slag (up to 70% on the hydration cement (XRD, heat of hydration, non evaporable water content and calcium hydroxide content curing under sealed conditions and their effect on the mechanical strength. The obtained results indicate that binary cements containing silica fume and ternary cements there was a significant increase of hydration rate at early age. At later ages, most of studied cements have an equivalent or greater strength that those obtained in the plain portland cement.En este trabajo se analiza la influencia de la incorporación al cemento portland de humo de sílice (hasta 10% y/o escoria granulada de alto horno (hasta 70% sobre la hidratación (DRX, calor de hidratación, contenido de agua no evaporable y de hidróxido de calcio, bajo condiciones de curado sellado y su incidencia sobre la resistencia mecánica. Los resultados obtenidos indican que en los cementos binarios con humo de sílice y en los cementos ternarios se produce un importante aumento de la velocidad de hidratación en las primeras edades, mientras que a edades más avanzadas la mayor parte del dominio estudiado alcanza o supera la resistencia obtenida por el cemento portland sin adición.

Bonavetti, V. L.

2014-09-01

304

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.

305

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

Energy Technology Data Exchange (ETDEWEB)

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 CO{sub 2} 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.

Gudenau, H.W.; Senk, D.; Fukada, K.; Babich, A.; Froehling, C.; Garcia, L.L.; Formoso, A.; Alguacil, F.J.; Cores, A. [University of Aachen, Aachen (Germany)

2003-10-01

306

Production of carbon included sinter and evaluation of its reactivity in a blast furnace environment  

Energy Technology Data Exchange (ETDEWEB)

Recently, the reduction in the amount of the CO{sub 2} emission has become an important issue. It is important to increase the reactivity of iron sources used in a blast furnace to decrease of CO{sub 2} emission. Therefore, the carbon composite iron ore agglomerates are significant. The production experiments of a new agglomerate named CIS (Carbon Included Sinter), where green balls were granulated by a model pan pelletizer were carried out using pot tests. The reduction of produced CIS with CO-CO{sub 2} gas mixture were examined, and were compared with that of ordinary sinter ore. Also, the softening and melting property tests of 50% CIS-50% sinter mixed layer were carried out and compared with the results using 100% sinter layer. The results are summarized as follows: (1) A new agglomerate, which an anthracite particle was surrounded by a shell with the same components as ordinary sinter ore, was produced by sintering pot test. (2) When CIS was reduced by CO-CO{sub 2} gas mixture at 1, 273 K, the degree of reduction achieved 80% in 120 min, even though ordinary sinter ore achieved less degree of reduction. (3) 250 g CIS-250 g ordinary sinter ore packed bed achieved 1/3 maximum pressure drop of 500 g ordinary sinter ore packed bed in the softening-melting property test.

Kamijo, C.; Matsumura, M.; Kawaguchi, T. [Sumitomo Metal Industry Ltd., Ibaraki (Japan)

2009-07-01

307

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

Science.gov (United States)

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.

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

2011-01-01

308

Strength properties of concrete incorporating coal bottom ash and granulated blast furnace slag.  

Science.gov (United States)

Coal bottom ash (CBA) and fly ash (FA) are by-products of thermal power plants. Granulated blast-furnace slag (GBFS) is developed during iron production in iron and steel plants. This research was conducted to evaluate the compressive strength property and some durability characteristics of concrete incorporating FA, CBA, and GBFS. FA is used as an effective partial cement replacement; CBA and GBFS are used as partial replacement for fine aggregate without grinding. Water absorption capacity, unit weight and compressive strengths in 7, 28, and 90-day ages were assessed experimentally. For these experiments, concrete specimens were produced in the laboratory in appropriate shapes. The samples are divided into two main categories: M1, which incorporated CBA and GBFS; and M2, which incorporated FA, CBA, and GBFS. Remarkable decreases are observed in compressive strength and water absorption capacity of the concrete; bulk density of the concrete is also decreased. It can be concluded that if the content of CBA and GBFS is limited to a reasonable amount, the small decreases in strength can be accepted for low strength concrete works. PMID:16580833

Ozkan, Omer; Yüksel, Isa; Murato?lu, Ozgür

2007-01-01

309

Iron ore chemical composition influence on the permeability of the blast furnace 1 of Special Steels Company of Itabira, ACESITA, Brazil; Influencia da composicao quimica do minerio de ferro na permeabilidade do alto forno I da ACESITA  

Energy Technology Data Exchange (ETDEWEB)

According to literature, Si O{sub 2}/Al{sub 2} O{sub 3} relations in the gangue of the iron ores affect the formation of the softening and the melting zone and, consequently, the permeability in the blast furnace. Using operating indexes of the ACESITA blast furnace 1, this work analyzes the influence of Si O{sub 2}/Al{sub 2} O{sub 3} relations in the iron ore on blast furnace permeability. It was concluded that an increase in the Al{sub 2} O{sub 3} content of the burden decreases the permeability of the blast furnace. (author). 2 refs., 4 figs., 2 tabs.

Pereira, Felipe J.N. [Companhia de Acos Especiais Itabira (ACESITA), Itabira, MG (Brazil); Rezende, Hermano A.D. de; Figueira, Renato M.; Tavares, Roberto P.; Castro, Luiz F.A. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Engenharia

1991-12-31

310

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

311

Increased use of natural gas in blast furnaces in North America; Utilisation accrue du gaz naturel dans les hauts-fourneaux d'Amerique du Nord  

Energy Technology Data Exchange (ETDEWEB)

Steel makers routinely inject alternate fuels into their blast furnaces that remain the heart of the integrated steel mill. Throughout the 1990's, gas industry sponsored tests at integrated steel mills demonstrated that natural gas injection could successfully provide up to 50% of a blast furnace's total energy requirements, reduce coke usage by 34% per kg of iron produced, increase productivity up to 30% and reduce operating costs by $4.40 to $5.50 per 10{sup 3} kg of iron produced. The success of these tests was instrumental in increasing total natural gas blast furnace injection in North America from under 850 10{sup 6} m{sup 3} (30 billion cubic feet) per year in 1985 to over 3.3 10{sup 9} m{sup 3} (116.5 billion cubic feet) per year currently. Pulverized coal injection (PCI) has been clearly demonstrated to reduce coke consumption and therefore operating costs although the use of PCI provides little or no flexibility in production levels from a particular furnace. Worldwide steel demand/use is cyclical and to remain competitive, plants must adjust production to match market demands while controlling total production costs and maintaining the operation's profitability. Recent blast furnace operating practices demonstrate that co-injecting natural gas along with pulverized coal can provide the benefits of each individual fuel. This paper provides a historic perspective on North American blast furnaces, their operation and the use of natural gas in relation to other fuels routinely injected into the blast furnace. The perspective leads to a projection of the impact of natural gas co-injection in North American integrated steel plants over the next 5 years. (authors)

Rogers, B.E.; Smith, M.R. [Union Gas Limited (Canada)

2000-07-01

312

Upper limits to combustibility of pulverized coal in blast furnace raceway and desirable injection position. Koro raceway bu de no bifuntan no nensho ryo genkai to fukikomi ichi no tekisei ka  

Energy Technology Data Exchange (ETDEWEB)

Based on the combustion experiment on pulverized coal and analysis of a mathematical model, upper limits of pulverized coal injection and grain size with due regard to combustibility, and optimum injection method of pulverized coal to the blast furnace with regard to form of the raceway were investigated. An equation was derived for the estimation of the upper limits to the coal injection rate at which the pulverized coal can burn 100% in the tuyere combustion zone, and it was made clear that the upper limit in the particle size of granular coal is 0.70mm in terms of characteristic particle diameter. A relational expression was derived for optimum injection position of pulverized coal, injection rate of pulverized coal, and characteristic particle diameter to clarify that it is necessary to bring the injection position near the tuyere nose when the injection rate is increased. Since April, 1990, Kimitsu No.4 blast furnace continued stable operation at a high rate coal injection of 132kg/t, proving that the coke replacement ratio does not decrease at a low theoretical flame temperature of 2,050 {degree} C. 23 refs., 7 figs., 4 tabs.

Amano, S.; Yamaguchi, K.; Tamura, K.; Sugata, M.; Ueno, H.; Yamaguchi, K. (Nippon Steel Corp., Tokyo (Japan))

1991-06-01

313

Combustion of waste oils simulating their injection in blast furnace tuyeres  

Directory of Open Access Journals (Sweden)

Full Text Available A study has been made of the combustion of different waste oils produced in an iron and steel works. Combustion is achieved by injecting the waste oil at flows of 10-20 kg/h in a combustion chamber that simulates the conditions of the blast furnace tuyere zone. The waste oil is preheated to 65-90 °C in order to achieve conditions of fluidity and is injected by spraying into the combustion chamber. During combustion the temperatures and the CO2, O2, CO N2 and H2 contents of the gases in the combustion chamber are constantly recorded. The efficiency of the combustion of each waste oil is determined.

Se realiza un estudio de la combustión de diferentes aceites residuales que se producen en las plantas siderúrgicas. La combustión se consigue al inyectar el aceite residual, con caudales de 10-20 kg/h, en una cámara de combustión que simula las condiciones del horno alto en la zona de toberas. El aceite residual se precalienta a 65-90 °C para conseguir las condiciones de fluidez y se inyecta en la cámara de combustión. Durante la combustión, se registran de modo continuo las temperaturas y los contenidos de CO2, O2, CO, N2 y H2 en los gases de la cámara de combustión. Se calcula la eficiencia de la combustión de cada aceite residual.

Cores, A.

2009-04-01

314

Use of blast furnace granulated slag as a substrate in vertical flow reed beds: field application.  

Science.gov (United States)

Research was conducted at Middle East Technical University (METU), Ankara, Turkey in 2000 to determine whether a reed bed filled with an economical Turkish fill media that has high phosphorus (P) sorption capacity, could be implemented and operated successfully under field conditions. In batch-scale P-sorption experiments, the P-sorption capacity of the blast furnace granulated slag (BFGS) of KARDEMIR Iron and Steel Ltd., Co., Turkey, was found to be higher compared to other candidate filter materials due to its higher Ca content and porous structure. In this regard, a vertical subsurface flow constructed wetland (CW) (30 m(2)), planted with Phragmites australis was implemented at METU to treat primarily treated domestic wastewater, at a hydraulic rate of 100 mm d(-1), intermittently. The layers of the filtration media constituted of sand, BFGS, and gravel. According to the first year monitoring study, average influent and effluent total phosphorus (TP) concentrations were 6.61+/-1.78 mg L(-1) and 3.18+/-1.82 mg L(-1); respectively. After 12 months, slag samples were taken from the reed bed and P-extraction experiments were performed to elucidate the dominant P-retention mechanisms. Main pools for P-retention were the loosely-bounded and Ca-bounded P due to the material's basic conditions (average pH>7.7) and higher Ca content. This study indicated the potential use of the slag reed bed with higher P-removal capacity for secondary and tertiary treatment under the field conditions. However, the P-sorption isotherms obtained under the laboratory conditions could not be used favorably to determine the longevity of the reed bed in terms of P-retention. PMID:17070037

Asuman Korkusuz, E; Beklio?lu, Meryem; Demirer, Göksel N

2007-08-01

315

BIO-PCI, Charcoal injection in Blast Furnaces: State of the art and economic perspectives  

Directory of Open Access Journals (Sweden)

Full Text Available The injection of grinded particles of charcoal through the tuyeres in Blast Furnaces, here coined Bio-PCI, presents as an attractive and plausible alternative to significantly reduce the CO2 emissions generated during hot metal production. In this contribution a summary of the technological fundaments, benefits and limitations of the incorporation of Bio-PCI is presented. Additionally the principal economic challenges of renewables fuel in ironmaking are exposed, with especial interest in the main productions costs of charcoal making. In this sense, a strategic question arises: can the residual biomass drive the emergence of Bio-PCI?, our analysis leads to conclude that the use of residual biomass (e.g. agricultural and forestry residues may significantly reduce the production cost in 120-180 USD/t in comparison to primary woods sources, this naturally increment the economical attractiveness of Bio-PCI substitution.La inyección de carbón vegetal por toberas en Altos Hornos, aqui denominada Bio-PCI, se presenta como una forma atractiva y realista de reducir significativamente las emisiones de CO2 generadas durante la producción de arrabio. En esta contribución se presenta un resumen de los fundamentos tecnológicos, los beneficios y las limitaciones de la incorporación de la tecnología del Bio-PCI. Adicionalmente se exponen los retos económicos que enfrentan los combustibles renovables a los fósiles, con especial interés en los principales costos de producción del carbón vegetal. En este sentido se plantea una pregunta estratégica: ¿puede la biomasa residual impulsar el desarrollo de la Bio-PCI?. Nuestro análisis conlleva a concluir que la utilización de biomasa residual (residuos forestales y agrícolas puede reducir sensiblemente el costo del carbón vegetal entre 120-180 USD/t en comparación con biomasa primaria, incrementando su competitividad frente al carbón mineral.

Feliciano-Bruzual, C.

2013-12-01

316

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

Directory of Open Access Journals (Sweden)

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.

Higuera, I.

2012-06-01

317

Injection of coal fines and charcoal fines mixtures by blast furnace`s tuyere; Injecao de misturas de finos de carvoes mineral e vegetal atraves das ventaneiras do alto-forno  

Energy Technology Data Exchange (ETDEWEB)

In general, fines injection by tuyere contributes directly to iron pig production in terms of reducing costs. Talking about Brazilian case, this paper has studied coal fines and charcoal fines mixtures combustion under conditions similar to blast furnace`s. In conclusion, this simulation showed that the mixture has presented a better performance than the other presented by coal fines or charcoal fines separately. 5 refs., 4 figs., 1 tab

Weber, Stephan Heinz J.V. [Industria de Aco Korf S.A. (IKOSA), Rio de Janeiro, RJ (Brazil); Figueira, Renato Minelli; Castro, Luiz Fernando Andrade de; Tavares, Roberto Parreiras [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenheria Metalurgica; Birkhauser, Lothar [Mannesmann SA, Belo Horizonte, MG (Brazil); Gudenau, Heinrich W. [Technische Hochschule Aachen (Germany)

1991-12-31

318

Hidróxidos duplos lamelares à base de escória de alto forno Layered double hydroxides produced from blast furnace slag  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Hydrotalcite like compounds (HT) were prepared by co-precipitation (Mg/Al = 3.5), using an acid solution with blast furnace slag and MgCl2.6H2O and aqueous solutions of NaOH. The following synthesis variables were investigated: temperature (30 and 45 ºC) and pH (9 and 12). Depending of the temperature two systems were observed: Mg-Al-CO3 (T = 30 ºC); Mg-Al-Cl-CO3 (T = 45 ºC). An increase in the pH of synthesis and Mg2+ concentration produced HTs well-crystallized a...

Monaliza Maia Rebelo; Márcia Valéria Porto de Oliveira Cunha; José Augusto Martins Corrêa

2012-01-01

319

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

Science.gov (United States)

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.

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

2013-12-01

320

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)

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)

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

 
 
 
 
321

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

Science.gov (United States)

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

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

2012-01-01

322

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

Science.gov (United States)

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.

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

2014-04-01

323

Incorporação de lama de alto forno em cerâmica vermelha Incorporation of blast furnace sludge into red ceramic  

Directory of Open Access Journals (Sweden)

Full Text Available Este trabalho tem por objetivo caracterizar um resíduo siderúrgico, a lama de alto forno, e avaliar o efeito da sua incorporação até 20% em peso nas propriedades e na microestrutura de uma massa argilosa. O resíduo foi submetido a ensaios de caracterização mineralógica, química, física e morfológica. Foram preparados corpos de prova por prensagem uniaxial a 20 MPa para queima em forno de laboratório a 900 ºC. As propriedades físicas e mecânicas avaliadas foram: retração linear, absorção de água e tensão de ruptura à flexão. A microestrutura das cerâmicas queimadas foi avaliada por microscopia eletrônica de varredura. Os resultados mostraram que a lama de alto forno é constituída predominantemente de compostos de ferro e de material carbonoso. A granulometria deste resíduo é favorável à incorporação em cerâmica vermelha. Entretanto, o resíduo ocasionou um efeito deletério nas propriedades físicas e mecânicas da cerâmica queimada.This work has for objective to characterize a steel making plant waste, the blast furnace sludge, and to evaluate the effect of its incorporation, up to 20 wt.%, on the properties and microstructure of a clayey ceramic used for the fabrication of bricks and roofing tiles. The waste was submitted to mineralogical, chemical and physical tests. In order to determine the physical and mechanical properties such as linear shrinkage, water absorption and flexural rupture strength, specimens were prepared by uniaxial mold-press at 20 MPa and then fired in a laboratory furnace at 900 ºC. The microstructure of the fired ceramics was evaluated by scanning electron microscopy. The results showed that the blast furnace sludge is predominantly composed of iron compounds and carbonaceous material. The particle size of the waste is appropriated for its incorporation into red ceramics. However, the waste incorporation resulted in deleterious effect on the physical and mechanical properties on the fired ceramics.

C. M. F. Vieira

2007-12-01

324

Characterization of pulverized and granular coal injection chars  

Energy Technology Data Exchange (ETDEWEB)

Coal injection into the blast furnace at moderate injection rates (<150 kg/tHM) poses no significant technical problems and requires no special precautions. However, high injection rates (>150 kg/tHM) require detailed knowledge of the overall process as well as information dealing with the behaviour of various injected materials, both in the blowpipe-tuyere and in the blast furnace raceway. For these reasons, in 1992, CETC undertook an extensive program to study the fundamental aspects of coal injection. Several reports on various aspects of this work have appeared. In this paper, we consider the characterization of chars produced from both pulverized and granular coal injection.(orig.)

MacPhee, J.A.; Hutny, W.P.; Giroux, L. [Canada Centre for Mineral and Energy Technology (CANMET), Nepean, ON (Canada). Natural Resources

1997-12-31

325

Kinetic sorption modelling of Cu, Ni, Zn, Pb and Cr ions to pine bark and blast furnace slag by using batch experiments.  

Science.gov (United States)

Storm water and landfill leachate can both contain significant amounts of toxic metals such as Zn, Cu, Pb, Cr and Ni. Pine bark and blast furnace slag are both residual waste products that have shown a large potential for metal removal from contaminated water. There are however many variables that must be optimized in order to achieve efficient metal retention. One of these variables is the time of which the solution is in contact with each unit of filter material. Metal sorption was studied in two laboratory experiments to improve the knowledge of the effects of contact time. The results showed that pine bark was generally more efficient than blast furnace slag when the metal concentrations were relatively small, whereas blast furnace slag sorbed most metals to a larger extent at increased metal loads. In addition, sorption to blast furnace slag was found to be faster than metal binding to pine bark. A pseudo-second-order kinetic model was able to describe the data well within 1000 s of reaction time. PMID:17532623

Nehrenheim, E; Gustafsson, J P

2008-04-01

326

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

327

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)

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.

Veena Sahajwalla; Sushil Gupta

2005-04-15

328

Development of an Operation Support System for the Blast Furnace in the Ironmaking Process: Large-scale Database-based Online Modeling and Integrated Simulators  

Science.gov (United States)

In the pig-ironmaking process, factors that cause operation malfunctions have increased with both the enlargement of the blast furnace and the increasing use of low quality ore. Therefore, an operation support system that predicts blast furnace performance is demanded. This paper reports the development of a blast furnace operation support system with an integrated simulator and “Large-scale database-based Online Modeling (LOM).” To develop the integrated simulator, a sophisticated burden distribution model is integrated with a two-dimensional total internal phenomenon model for the stationary state by using Java technology. Moreover, an integrated simulator for the partial non-stationary state is developed by modifying the two-dimensional total internal phenomenon model for the stationary state. To incorporate the LOM system into the operation support system, a cross-platform LOM system with general versatility is rebuilt by an existing LOM system. The operation support system is realized by the simulator of the physical modeling method and the LOM of the local modeling method. As a result, the operation support system predicts a dynamic molten pig-iron temperature in the blast furnace. The operation support system is expected to provide staff with useful information.

Ogai, Harutoshi; Ogawa, Masatoshi; Uchida, Kenko; Matsuzaki, Shinroku; Ito, Masahiro

329

Integration of the blast furnace route and the FINEX {sup registered} -Process for low CO{sub 2} hot metal production  

Energy Technology Data Exchange (ETDEWEB)

The blast furnace is the most important process for the production of hot metal. An integral part of this process route is the coking of coal and sintering of fine ore. The FINEX {sup registered} -process is a new technology for hot metal production which uses untreated fine ores and coal instead of sinter and coke. This paper deals with the investigation of integration concepts of the blast furnace and FINEX {sup registered}. Low reduced iron (LRI) and/or reducing gas are/is produced in FINEX {sup registered} and are/is considered as substitute/s of burden and fuel in the blast furnace, respectively. In the article the overall fuel demand and CO{sub 2} emissions for the integration of the blast furnace and FINEX {sup registered} are shown. For that reason two case studies for the integration are carried out and compared with the base case, that is, the two-independent processes. The CO{sub 2} emissions are calculated considering the fuel and electric power consumption of the different cases. (Copyright copyright 2012 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Thaler, Christoph; Schenk, Johannes L. [Montanuniversitaet Leoben, Chair of Metallurgy, Leoben (Austria); Tappeiner, Tamara; Kepplinger, Werner L. [Montanuniversitaet Leoben, Institute of Process Engineering and Environmental Protection, Leoben (Austria); Plaul, Jan Friedemann [Siemens VAI Metals Technologies GmbH, Linz (Austria); Schuster, Stefan [Voestalpine Stahl GmbH, Linz (Austria)

2012-02-15

330

Calculation of optimum conditions for blast furnace pulverized coal injection (II): combustion of pulverized coal in the raceway, the optimization of injection  

Energy Technology Data Exchange (ETDEWEB)

Reports are given on 1) the use of a complete mixing model in a theoretical study of combustion in a blast furnace raceway, and 2) an attempt to optimize injection conditions using the resulting combustion analysis in combination with the theory of combustion in a blowpipe. 4 references, 2 figures.

Nomura, S.

1986-01-01

331

Natural gas utilization in blast furnace of non-integrated pig-iron plants; Utilizacao de gas natural em altos fornos de usinas siderurgicas nao-integradas  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the authors investigate the technical and economical aspects of the natural gas injection in non-integrated pig-iron plants using charcoal in the blast furnace. The effects of the natural gas injection concerning the blast furnace flame temperature, charcoal consumption, productively and permeability are analyzed. It was found that the injection is beneficial in many ways, such as in the improvement of the productivity and quality, if the flame temperature is kept within an appropriate range. In the financial-economic project`s evaluation, the cash flow for the natural gas injection was analysed considering two blast conditions: through the drying and oxygen enrichment of the air. A sensibility analysis is presented in which the internal rate of return of the investment varies according to the prices of charcoal and oxygen. 3 refs., 3 figs., 3 tabs

Abreu, D.G. de [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Castro, L.F.A. de; Figueira, R.M.; Tavares, R.P. [Minas Gerais Univ., Belo Horizonte, MG (Brazil)

1990-12-31

332

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

Directory of Open Access Journals (Sweden)

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.

Gudenau, H. W.

2003-10-01

333

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)

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)

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

334

IDENTIFICATION OF PHASE COMPOSITION OF BINDERS FROM ALKALI-ACTIVATED MIXTURES OF GRANULATED BLAST FURNACE SLAG AND FLY ASH  

Directory of Open Access Journals (Sweden)

Full Text Available The prepared alkali-activated binders (AAB and composites using suitable latent hydraulic raw materials represent an alternative to materials based on Portland cements. This paper deals with ways how to influence the functional parameters of AAB by setting up mixtures of granulated blast furnace slag (GBFS and fly ash with selected chemical compositions. In this way the course of hydration process is modified and the phase composition of products of alkali activation is changed as well as their final properties. The amorphous character of the hydration products makes evaluation of the phase composition of hardened AAB difficult and significantly limits the number of experimental techniques suitable to characterise their phase composition. It was observed that measuring the pH of water extracts obtained from the alkali-activated mixtures can give supplementary information about the process of hardening of alkali-activated mixtures of GBFS and fly ash.

JOZEF VL?EK

2014-03-01

335

Hidróxidos duplos lamelares à base de escória de alto forno Layered double hydroxides produced from blast furnace slag  

Directory of Open Access Journals (Sweden)

Full Text Available Hydrotalcite like compounds (HT were prepared by co-precipitation (Mg/Al = 3.5, using an acid solution with blast furnace slag and MgCl2.6H2O and aqueous solutions of NaOH. The following synthesis variables were investigated: temperature (30 and 45 ºC and pH (9 and 12. Depending of the temperature two systems were observed: Mg-Al-CO3 (T = 30 ºC; Mg-Al-Cl-CO3 (T = 45 ºC. An increase in the pH of synthesis and Mg2+ concentration produced HTs well-crystallized and with greater values of all cell parameters. The study showed the potentiality of BFS in the synthesis of well-crystallized LDHs without the presence of other crystalline phases.

Monaliza Maia Rebelo

2012-01-01

336

Hidróxidos duplos lamelares à base de escória de alto forno / Layered double hydroxides produced from blast furnace slag  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese [...] Abstract in english Hydrotalcite like compounds (HT) were prepared by co-precipitation (Mg/Al = 3.5), using an acid solution with blast furnace slag and MgCl2.6H2O and aqueous solutions of NaOH. The following synthesis variables were investigated: temperature (30 and 45 ºC) and pH (9 and 12). Depending of the temperatu [...] re two systems were observed: Mg-Al-CO3 (T = 30 ºC); Mg-Al-Cl-CO3 (T = 45 ºC). An increase in the pH of synthesis and Mg2+ concentration produced HTs well-crystallized and with greater values of all cell parameters. The study showed the potentiality of BFS in the synthesis of well-crystallized LDHs without the presence of other crystalline phases.

Monaliza Maia, Rebelo; Márcia Valéria Porto de Oliveira, Cunha; José Augusto Martins, Corrêa.

337

Experiences with the utilization of waste plastics in blast furnaces; Erfahrungen mit der Altkunststoff-Verwertung im Hochofenprozess  

Energy Technology Data Exchange (ETDEWEB)

With a worldwide production of 1,417 million tons in 2010 steel is the most important metallic construction material. At the end of the life cycle steel is recycled completely. Subsequently, plastics follow with a worldwide production of 265 million tones in 2010. In contrast to the production of steel the recycling of plastics at the end of the life cycle resulted in a plurality of process solutions. Voestalpine Stahl GmbH (Linz, Austria) has opened a new niche process by implementing recycling rates. Under this aspect, the contribution under consideration reports on the use of waste plastics as a substitute for primary raw materials and as a reducing agent in blast furnaces.

Buergler, Thomas [voestalpine Stahl GmbH, Linz (Austria). Unternehmensbereich Roheisen; Kieberger, Nina [voestalpine Stahl GmbH, Linz (Austria). Projekt Kunststoffeinblasanlage

2012-11-01

338

Utilization of fly ash and ground granulated blast furnace slag as an alternative silica source in reactive powder concrete  

Energy Technology Data Exchange (ETDEWEB)

Reactive powder concrete (RPC) is an ultra high strength cement-based material. Cement and silica fume (SF) content of RPC are generally rather high compared to the conventional concrete. The aim of this study is to decrease the cement and SF content of RPC using with fly ash (FA) and/or ground granulated blast furnace slag (GGBFS). The effect of these mineral admixtures on compressive strength of RPC has been investigated under autoclave curing. In the first stage, the effect of autoclave time and SF content on compressive strength was determined. In the second stage, SF was gradually decreased and cement was replaced with FA and/or GGBFS at different proportions. The microstructure was investigated by scanning electron microscope (SEM). Test results indicate that, the utilization of FA and/or GGBFS in RPC is possible without significant mechanical performance loss. SEM micrographs revealed the tobermorite having different morphology. 18 refs., 5 figs., 5 tabs.

Halit Yazici; Huseyin Yigiter; Anil S. Karabulut; Bulent Baradan [Dokuz Eylul University, Izmir (Turkey). Department of Civil Engineering, Engineering Faculty

2008-09-15

339

The radiation stability of ground granulated blast furnace slag/ordinary Portland cement grouts containing organic admixtures  

Energy Technology Data Exchange (ETDEWEB)

At the British Nuclear Fuels (BNFL) Sellafield reprocessing plant in the United Kingdom, cement grouts based on ground granulated blast-furnace slag (BFS) and ordinary Portland cement (OPC) are used extensively for immobilizing radioactive wastes. These grouts have excluded organic admixtures in order to reduce process complexity and uncertainties, regarding the performance of organic admixtures with BFS/OPC grouts, particularly under irradiation. This study has investigated the effects of sulfonated melamine formaldehyde and naphthalene condensates on grout properties. The results show grout settlement and strengths increase on addition of additives, with the additives remaining largely in the pore solution. Under irradiation the additives breakdown liberating hydrogen and carbon dioxide. Strength and product dimensions are unaffected by irradiation.

Palmer, J.D.; Fairhall, G.A. [British Nuclear Fuels, Sellafield (United Kingdom)

1993-12-31

340

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

 
 
 
 
341

Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag--An overview.  

Science.gov (United States)

The partial replacement of clinker, the main constituent of ordinary Portland cement by pozzolanic or latent hydraulic industrial by-products such as ground granulated blast furnace slag (GGBFS), effectively lowers the cost of cement by saving energy in the production process. It also reduces CO2 emissions from the cement plant and offers a low priced solution to the environmental problem of depositing industrial wastes. The utilization of GGBFS as partial replacement of Portland cement takes advantage of economic, technical and environmental benefits of this material. Recently offshore, coastal and marine concrete structures were constructed using GGBFS concrete because high volume of GGBFS can contribute to the reduction of chloride ingress. In this paper, the influence of using GGBFS in reinforced concrete structures from the durability aspects such as chloride ingress and corrosion resistance, long term durability, microstructure and porosity of GGBFS concrete has been reviewed and discussed. PMID:16930831

Song, Ha-Won; Saraswathy, Velu

2006-11-16

342

Instrumentation and operational data of small blast furnace for performance improvement; Instrumentacao e dados operacionais de altos fornos de pequeno porte visando melhoria de desempenho  

Energy Technology Data Exchange (ETDEWEB)

The most part of iron making operating with small blast furnace are lacking of a minimum instrumentation for a satisfactory process evaluation, and in some cases, nevertheless the existence of a good data gathering infra-structure, the equipment or the acquired data are not correctly used. In this work, the minimum instrumentation and operational data necessary for a good process control are presented, and their importance are discussed. Using these information it is demonstrated their use for taking correct operational actions, which must be standardized and executed by all the furnace operators. Various control models are discussed. (author) 2 tabs.

Castro, Luiz F.A. de; Tavares, Roberto P. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Metalurgica

1996-12-31

343

Mathematical model of blast furnace raceway zone with pulverized coal and fine ore injection. Bifuntanter dot funkoseki fukugo fukikomi ni kansuru koro raceway sugaku model  

Energy Technology Data Exchange (ETDEWEB)

One dimensional mathematical model with the consideration of gas flow in the raceway and heat transfer during pulverized coal ( coal )and fine ore injection was developed. Parameters of thermal decomposition and reduction experiment of fine ore at high temperature gas flow, combustion experiment of PC by using experimental combustion furnace and actual blast furnace were determined and the reaction phenomena in the raceway were analyzed. The reaction and distribution of temperature and gas composition inside the raceway has been greatly affected by temperature drop of the gas caused by the complex mass injection of PC and fine ore, however effect of amount of injection of PC and fine ore on the combustion degree of fine coal has been small. Reaction rate of PC has increased with the oxygen enrichment. In case of complex injection, it was estimated that the increase of blast temperature has been more effective than oxygen enrichment to promote reduction inside the raceway. 41 refs., 9 figs., 6 tabs.

Xingguo, X.; Nozawa, K.; Sasahara, S.; Shimizu, M.; Inaba, S. (Kobe Steel Ltd., Kobe (Japan))

1992-07-01

344

Effect of pulverized coal injection on the distribution of pressure, temperature and fine particle fraction around blast furnace raceway. Koro raceway shuhenbu no atsuryoku, ondo oyobi tanzai funritsu ni oyobosu bifuntan fukikomi no eikyo  

Energy Technology Data Exchange (ETDEWEB)

Pulverized coal injection (PCI) tests were carried out using a coke-filled test furnace under conditions equivalent to those around blast furnace raceway, to clarify the combustion behavior of pulverized coal in a blast furnace and its effect on furnace phenomena. As a result, an increase in blast pressure due to PCI was strongly dependent on an increase in blast velocity due to pulverized coal combustion in a blow pipe. Since unburnt pulverized coal accumulated in the furnace was gasified with CO {sub 2} much faster than fine coke, it had less harmful influence on pressure drop in the furnace. Since coke consumption decreased by PCI in the receway, the desceding velocity of solid coke decreased at the peripheral part in blast furnace bosh, resulting in a decrease in heat flow ratio, and temperature rise at the peripheral part. This phenomenon was conceivable to be one of mechanisms increasing heat load with PCI at the peripheral part. 18 refs., 12 figs., 2 tabs.

Deguchi, M.; Shibata, K.; Fukuoka, M. (Kobe Steel, Ltd., Kobe, (Japan))

1990-05-01

345

The Balance of Titanium and Vanadium in the Blast Furnace with the Use of Sinter Containing a Titanium-Vanadium-Magnetite Concentrate  

Directory of Open Access Journals (Sweden)

Full Text Available The investigation concerned the use of sinter containing a titanium-vanadium-magnetite concentrate for the production of pig iron. Sinter containing 0,46 to 0,51 % TiO2 and 0,056 to 0,060 % vanadium was used for pig iron production in the blast furnace. Introducing 200 kg of this concentrate to the1 Mg sinter mix did not cause any deterioration of sinter quality.

Budzik, R.

2007-01-01

346

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)

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.

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

347

Preparation of a new sorbent with hydrated lime and blast furnace slag for phosphorus removal from aqueous solution.  

Science.gov (United States)

The removal of dissolvable inorganic phosphate (H(2)PO(4)(-)) by sorbents prepared from hydrated lime (HL) and blast furnace slag (BFS) was fundamentally studied by an orthogonal experiment design. Based on statistic analysis, it is revealed that the weight ratio of BFS/HL is the most significant variable, and an optimized preparation condition is figured out. With the increase of HL content, the adsorption capacity increases, suggesting that the HL plays the important role in the removal process in the gross. However, in the lower HL content, it is interesting that the adsorption capacity of as-prepared sorbents exceed the sum of the capacities of the same ratio of BFS and HL. The further analysis indicate the excess capacities linearly depend on the specific surface area of sorbents, suggesting that the removal of H(2)PO(4)(-) is closely related with the microstructure of sorbents in the lower HL content, according to the characterization with SEM, XRD and pore analysis. Additionally, an adsorption model and kinetic are discussed in this paper. PMID:19124194

Gong, Guozhuo; Ye, Shufeng; Tian, Yajun; Wang, Qi; Ni, Jiandi; Chen, Yunfa

2009-07-30

348

Investigative monitoring within the European Water Framework Directive: a coastal blast furnace slag disposal, as an example.  

Science.gov (United States)

The European Water Framework Directive (WFD) establishes a framework for the protection of estuarine and coastal waters, with the most important objective being to achieve 'good ecological status' for all waters, by 2015. Hence, Member States are establishing programmes for the monitoring of water quality status, through the assessment of ecological and chemical elements. These monitoring programmes can be of three types: surveillance monitoring; operational monitoring (both undertaken on a routine basis); and investigative monitoring (carried out where the reason of any exceedance for ecological and chemical status is unknown). Until now, nothing has been developed in relation to investigative monitoring and no clear guidance exists for this type of monitoring, as it must be tackled on a 'case-by-case' basis. Consequently, the present study uses slag disposal from a blast furnace, into a coastal area, as a case-study in the implementation of investigative monitoring, according to the WFD. In order to investigate the potential threat of such slags, this contribution includes: a geophysical study, to determine the extent of the disposal area; sediment analysis; a chemical metal analysis; and an ecotoxicological study (including a Microtox test and an amphipod bioassay). The results show that metal concentrations are several times above the background concentration. However, only one of the stations showed toxicity after acute toxicological tests, with the benthic communities being in a good status. The approaches used here show that contaminants are not bioavailable and that no management actions are required with the slags. PMID:18385866

Borja, Angel; Tueros, Itziar; Belzunce, Ma Jesús; Galparsoro, Ibon; Garmendia, Joxe Mikel; Revilla, Marta; Solaun, Oihana; Valencia, Victoriano

2008-04-01

349

Effect of B2O3 on the Structure and Viscous Behavior of Ti-Bearing Blast Furnace Slags  

Science.gov (United States)

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.

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

2014-08-01

350

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

Science.gov (United States)

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.

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

351

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

352

Degradation behaviour of a high CSR coke in an experimental blast furnace: Effect of carbon structure and alkali reactions  

Energy Technology Data Exchange (ETDEWEB)

A high CSR coke was tested in the LKAB's Experimental Blast Furnace (EBF) at Lulea. The evolution of physical and chemical properties of the centre-line coke samples were analysed by Light Optical Microscopy (LOM), BET N2 absorption and SEM/XRF/XRD. Alkali distribution in the EBF cokes was examined by XRF/SEM and EDS. Thermo Gravimetric Analysis (TGA) was used to measure isothermal and non-isothermal CO{sub 2} reactivity of the cokes. The crystalline order of carbon and the concentration of alkalis were found to increase as the coke descended through thermal reserve zone to the cohesive zone of the EBF. The crystallite height (L{sub c}) of EBF coke carbon displayed a linear correlation with the measured EBF temperatures demonstrating the strong effect of temperature on carbon structure of coke in the EBF. Alkali concentration of the coke was increased as it descended into the EBF, and was uniformly distributed throughout the coke matrix. The CO{sub 2} reactivity of lower zone cokes was found to increase when compared to the reactivity of the upper zones cokes, and was related to the catalytic effect of increased alkalis concentration. The deterioration of coke quality particularly coke strength and abrasion propensity were related to coke graphitisation, alkalization and reactivity. Coke graphitisation is shown to have a strong influence on the coke degradation behaviour in the EBF.

Hilding, T.; Gupta, S.; Sahajwalla, V.; Bjorkman, B.; Wikstrom, J.O. [University of Lulea, Lulea (Sweden)

2005-07-01

353

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

Science.gov (United States)

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

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

2012-10-15

354

Adoption of additional mechanical treatment of coke en route to blast furnaces in Ukrainian plants  

Energy Technology Data Exchange (ETDEWEB)

Methods are reviewed for improving coke quality which has declined due to: fall in coking properties of Donetsk coal and the need to bring coal with higher coking temperatures (1050-1100 C) from other coal areas; average age of refractory furnace liners which considerably exceeds the amortization period (20 years), resulting in reduction of heating temperatures by 15-30 C. The coke produced exhibits low mechanical strength and contains an excess of particles larger than 80 mm. Investigations are described carried out at the Bagleisk plant into mechanical treatment of coke and results obtained are given. The paper recommmends that supplementary breaking of large particles of coke be introduced into the feed line using deflecting steel plates 10-12 mm thick, lined with diabasic sheet and placed at the first transfer point of the coke feed. Results are given of trials of the system in several plants. The parameters given in the drawing should be set in accordance with local conditions. 3 references.

Aksenin, N.P.; Kryukov, A.N.; Velichko, S.A.; Kurbatova, M.Yu.; Doroshenko, L.N.

1985-11-01

355

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

356

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

Science.gov (United States)

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

Zhong, Shiyun; Ni, Kun; Li, Jinmei

2012-07-01

357

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)

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.

Mejía, J. M.

2013-09-01

358

Study of blast furnace raceway conditions with high rates of injection of coal and oxygen and typical blast pressures. Final report; Studio delle condizione della raceway dell`altoforno ad altissimi tassi di iniezione di carbone ed ossigeno e alle pressioni del vento. Rapporto finale  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to study the blast furnace raceway conditions typical blast pressures and very high rates of oxygen and coal. The study concentrated in particular on the role of the pressure, which is an important parameter affecting the process in the zone in front of tuyeres as far as the combustion behaviour, the raceway shape and its stability are concerned. For this study an experimental technique on a Centro Sviluppo Materiali (CSM) pilot apparatus named Raceway Plant has been set up. The research activity is apart of more general study which also involves British Steel and Hoogovens, having the aim of developing the know-how concerning the blast furnace raceway, which is considered critical for a smooth blast furnace operation. Moreover its importance will increase because of development of a current trend towards lower coke consumption that involves different conditions at the tuyeres due to the massive use of coal injected.

Malgarini, G.; Di Sante, L.; Gualco, N. [Centro Sviluppo Materiali SpA, Roma (Italy)

1997-12-31

359

Evolution of temperature during modifications in the hearth internal profile blast furnace; Evolucao de temperatura durante alteracoes do perfil interno do cadinho do alto-forno  

Energy Technology Data Exchange (ETDEWEB)

An electrical model of hearth of the blast furnace was constructed to evaluate the internal profile of refractories. The advantages of the model, in relation to mathematical ones, are the facility for construction and easy way of obtaining measurements. The results obtained from model indicate that the isotherms move in the same way as the internal profile and that evaluations based on temperature measurements, such as heat flux, may have large errors if the thermocouples are located in regions of high thermal conductivity with small displacements. (author). 3 refs., 6 figs.

Figueira, Renato M.; Castro, Luiz F.A. de; Tavares, Roberto P.; Rezende Manetta, Helio de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenheria Metalurgica

1990-12-31

360

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 withoutro 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.

 
 
 
 
361

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)

362

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)

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

Taha, Gharib Mahmoud; Mosaed, Taghreed Mahmoud

2010-04-01

363

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

Energy Technology Data Exchange (ETDEWEB)

Perovskite type titanium-bearing blast furnace slag (TBBFS) and sulphate-modified titanium-bearing blast furnace slag (SO{sub 4}{sup 2-}/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 SO{sub 4}{sup 2-}/TBBFS catalysts. At low calcination temperature, the photocatalytic activities of SO{sub 4}{sup 2-}/TBBFS catalysts were markedly higher than TBBFS prepared under high calcination temperature, suggesting that the presence of surface SO{sub 4}{sup 2-} favored the photocatalytic reduction of Cr(VI)

Lei, X.F. [School of Materials and Metallurgy, Northeastern University, P.O. Box 313, Shenyang 110004 (China)], E-mail: leixuefei69@163.com; Xue, X.X. [School of Materials and Metallurgy, Northeastern University, P.O. Box 313, Shenyang 110004 (China)

2008-12-20

364

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)

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

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

1993-12-31

365

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

366

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)

367

Adequate operation of a wood coal fed blast furnace aiming less pollutant generation; Operacao adequada de um alto-forno a carvao vegetal visando uma menor geracao de carga poluidora  

Energy Technology Data Exchange (ETDEWEB)

This paper approaches all the necessary actions for an adequate operation of the wood coal fed blast furnaces. The document considers as an ideal operation the one presenting a low carbon specific consumption (kg/T of cast iron) and a high productivity, associated to a low generation of particulates in the atmosphere and a solid waste (slag) suitable for re-utilization.

Castro, Luiz Fernando Andrade de; Tavares, Roberto Parreiras; Ribeiro, Eduardo Delano Leite [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Engenharia; Jacomino, Vanusa Maria Feliciano [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Batista, Arnaldo Abranches Mota [Fundacao Estadual do Meio Ambiente (FEAM), Belo Horizonte, MG (Brazil); Lopes, Luiz Eduardo Furiati [Sindicato da Industria do Ferro no Estado de Minas Gerais (SINDIFER), Belo Horizonte (Brazil)

2001-07-01

368

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)

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)

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

369

Impaction of particle streams on a granular bed  

Science.gov (United States)

Impaction of particle streams on granular beds can be observed in various processes. One typical example is the burden distribution in an ironmaking blast furnace. The stream of heavy iron-bearing pellets impacts the pre-formed coke surface at the blast furnace throat region. The coke layer then can move and collapse. The formed burden profile is important in controlling the radial distribution of gas flow, and hence productivity and stability. In this paper, the impaction of pellets on the coke surface is investigated using discrete element method. A 90 degree sector is modelled with a pre-formed coke surface impacted by pellets flowing from a rotating chute. Microscopic analysis on the flow and force structures is carried out to examine the impaction with different chute angles and discharge rates.

Liu, Sida; Zhou, Zongyan; Dong, Kejun; Yu, Aibing; Tsalapatis, John; Pinson, David

2013-06-01

370

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

Directory of Open Access Journals (Sweden)

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.

Fernández-Jiménez, A.

1997-06-01

371

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)

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.

Joeri Van Mierlo

2013-03-01

372

Strength, leachability and microstructure characterisation of Na2SiO3-activated ground granulated blast-furnace slag solidified MSWI fly ash.  

Science.gov (United States)

The chemical composition and the leachability of heavy metals in municipal solid waste incinerator (MSWI) fly ash were measured and analysed. For the leachability of unstabilized MSWI fly ash it was found that the concentrations of Pb and Cr exceeded the leaching toxicity standard. Cementitious solidification of the MSWI fly ash by Na2SiO3-activated ground granulated blast-furnace slag (NS) was investigated. Results show that all solidified MSWI fly ash can meet the landfill standards after 28 days of curing. The heavy metals were immobilized within the hydration products such as C-S-H gel and ettringite through physical encapsulation, substitution, precipitation or adsorption mechanisms. PMID:17985665

Zhang, Dajie; Liu, Wenshi; Hou, Haobo; He, Xinghua

2007-10-01

373

Use of Cement Kiln Dust, Blast Furnace Slag and Marble Sludge in the Manufacture of Sustainable Artificial Aggregates by Means of Cold Bonding Pelletization  

Directory of Open Access Journals (Sweden)

Full Text Available In this work, three different samples of solid industrial wastes cement kiln dust (CKD, granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of artificial aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded artificial aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural aggregate were substituted with the artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in artificial aggregate sustainable production.

Raffaele Cioffi

2013-07-01

374

Efeito de escória de alto forno no crescimento radicular e na produtividade de arroz / Effect of blast furnace slag on root growth and yield of rice  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A utilização agrícola de resíduos industriais como fertilizantes decorre da necessidade de diminuir o efeito nocivo do acúmulo de nutrientes nos centros de produção. O objetivo deste trabalho foi avaliar os efeitos de escória de alto forno no crescimento radicular e na produtividade do arroz de terr [...] as altas irrigado por aspersão. O experimento foi realizado no campo, adotando-se o delineamento experimental de blocos casualizados, com cinco doses de escória de alto forno (0, 2.550, 5.100, 10.200 e 15.300 kg ha-1) com quatro repetições. A utilização de escória melhorou a condição química do solo, aumentou o crescimento e a superfície radicular, diminuiu o diâmetro das raízes e elevou os teores de silício no solo e na planta, resultando em aumento da produtividade. Abstract in english Agricultural use of industrial residues as fertilizers is due to the need of reducing nutrient accumulation in centers of production. The objective of this study was to evaluate the effects of blast furnace slag on root growth and productivity of highland rice irrigated by sprinkler. The experiment [...] was carried out on field conditions. The experimental design was a randomized block, with five rates of blast furnace (0, 2,550, 5,100, 10,200, and 15,300 kg ha-1) and four replications. Use of the slag improved chemical attributes of the soil, increased root growth and surface and reduced root diameter. It increased the silicon content in the soil and in the plant, resulting in higher yield.

Juliana Garcia, Carvalho-Pupatto; Leonardo Theodoro, Büll; Carlos Alexandre Costa, Crusciol; Munir, Mauad; Rosemeire Helena da, Silva.

375

Investigation of coal conversion under conditions simulating the raceway of a blast furnace using a pulsed air injection, wire-mesh reactor  

Energy Technology Data Exchange (ETDEWEB)

Operating difficulties are encountered when high coal injection rates are used into the blast furnace raceway. An insight into the problems has been gained using a wire mesh reactor, which has been modified to inject short (5-500 ms) pulses of air or O{sub 2}-enriched air through the sample holder, once the particles have reached peak experimental temperature. By manipulating the test procedure, it has been possible to measure the extents of successive pyrolysis, char combustion, and CO{sub 2}-gasification that occur under simulated raceway conditions. In the wire-mesh reactor, the release of volatiles was completed within the heat-up period {approximately} 300 ms, at a heating rate of 5000 C s{sup -1}. For 20 ms air pulse times, complete consumption of the inlet O{sub 2} occurred (with concentrations in the range 21-75%) and the extent of combustion was limited by the amount of O{sub 2} supplied (i.e., it was diffusion-limited). Extents of CO{sub 2}-gasification were measured in the temperature range 800-1500{sup o}C, and the results suggest than many seconds are needed to achieve a reasonable extent of gasification. Overall, the results indicate that the extents of combustion and gasification of the char in the raceway (residence time {lt} 50 ms) are likely to be low. However, a significant proportion of the char will subsequently react by gasification within the blast-furnace bed. Unreacted char and soot may either be trapped in the coke bed or entrained in the gas stream, giving rise to the problems observed at high coal injection rates. 25 refs., 10 figs., 6 tabs.

S. Pipatmanomai; N. Paterson; D.R. Dugwell; R. Kandiyoti [Imperial College (University of London), London (United Kingdom). Department of Chemical Engineering and Chemical Technology

2003-04-01

376

Efeito de escória de alto forno no crescimento radicular e na produtividade de arroz Effect of blast furnace slag on root growth and yield of rice  

Directory of Open Access Journals (Sweden)

Full Text Available A utilização agrícola de resíduos industriais como fertilizantes decorre da necessidade de diminuir o efeito nocivo do acúmulo de nutrientes nos centros de produção. O objetivo deste trabalho foi avaliar os efeitos de escória de alto forno no crescimento radicular e na produtividade do arroz de terras altas irrigado por aspersão. O experimento foi realizado no campo, adotando-se o delineamento experimental de blocos casualizados, com cinco doses de escória de alto forno (0, 2.550, 5.100, 10.200 e 15.300 kg ha-1 com quatro repetições. A utilização de escória melhorou a condição química do solo, aumentou o crescimento e a superfície radicular, diminuiu o diâmetro das raízes e elevou os teores de silício no solo e na planta, resultando em aumento da produtividade.Agricultural use of industrial residues as fertilizers is due to the need of reducing nutrient accumulation in centers of production. The objective of this study was to evaluate the effects of blast furnace slag on root growth and productivity of highland rice irrigated by sprinkler. The experiment was carried out on field conditions. The experimental design was a randomized block, with five rates of blast furnace (0, 2,550, 5,100, 10,200, and 15,300 kg ha-1 and four replications. Use of the slag improved chemical attributes of the soil, increased root growth and surface and reduced root diameter. It increased the silicon content in the soil and in the plant, resulting in higher yield.

Juliana Garcia Carvalho-Pupatto

2003-11-01

377

Thermoeconomical analysis of CO{sub 2} removal from the Corex export gas and its integration with the blast-furnace assembly and metallurgical combined heat and power (CHP) plant  

Energy Technology Data Exchange (ETDEWEB)

The paper presents the possibility of integration of the Corex process, blast furnace, CO{sub 2} removal installation and metallurgical combined heat and power (CHP) plant. Such an integration has significant advantages from the technical and environmental points of view. As the Corex export gas (after CO{sub 2} removal) is a highly valuable reducing agent, it is proposed to use it as a reducing gas injected to the thermal reserve zone of the blast-furnace process. Such an application leads first of all to a saving of coke. Besides the reduction of the consumption of coke, also the consumption of blast, high-purity oxygen, the amount and lower heating value (LHV) of blast-furnace gas as well as many other parameters are changed. CO{sub 2} separation is realized by physical absorption, which has been chosen and analysed as the most appropriate technology in similar applications. Higher LHV of the Corex gas obtained by CO{sub 2} removal provides the possibility of its utilization in the gas-and-steam CHP plant. Such a possibility has been also tested by means of energy and economical analyses.

Krzysztof Lampert; Andrzej Ziebik; Wojciech Stanek [Silesian University of Technology, Gliwice (Poland). Institute of Thermal Technology

2010-02-15

378

Thermoeconomical analysis of CO{sub 2} removal from the Corex export gas and its integration with the blast-furnace assembly and metallurgical combined heat and power (CHP) plant  

Energy Technology Data Exchange (ETDEWEB)

The paper presents the possibility of integration of the Corex process, blast furnace, CO{sub 2} removal installation and metallurgical combined heat and power (CHP) plant. Such an integration has significant advantages from the technical and environmental points of view. As the Corex export gas (after CO{sub 2} removal) is a highly valuable reducing agent, it is proposed to use it as a reducing gas injected to the thermal reserve zone of the blast-furnace process. Such an application leads first of all to a saving of coke. Besides the reduction of the consumption of coke, also the consumption of blast, high-purity oxygen, the amount and lower heating value (LHV) of blast-furnace gas as well as many other parameters are changed. CO{sub 2} separation is realized by physical absorption, which has been chosen and analysed as the most appropriate technology in similar applications. Higher LHV of the Corex gas obtained by CO{sub 2} removal provides the possibility of its utilization in the gas-and-steam CHP plant. Such a possibility has been also tested by means of energy and economical analyses. (author)

Lampert, Krzysztof; Ziebik, Andrzej; Stanek, Wojciech [Institute of Thermal Technology, Silesian University of Technology, Konarskiego 22, 44-100 Gliwice (Poland)

2010-02-15

379

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)

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)

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

380

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)

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)

Janz, J. [Stahlwerke Bremen GmbH (Germany)

1996-12-31

 
 
 
 
381

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

2013-03-01

382

Simulation of blast-furnace raceway conditions in a wire-mesh reactor: interference by the reactions of molybdenum mesh and initial results  

Energy Technology Data Exchange (ETDEWEB)

A novel trapped air injection system has been built for a wire-mesh reactor to enable tests with short exposure times to air that are intended to simulate typical residence times in blast-furnace raceways. Initial tests have shown that the molybdenum wire-mesh sample-holder reacts with O{sub 2} under conditions intended for this work. By varying the proportions of solid MoO{sub 2} (weight gain), vapor phase oxides (weight loss) may form, depending on reaction conditions. Oxide formation pathways thus become relevant to coal weight loss determinations during experiments. If, in addition to solid MoO{sub 2} formation, significant formation of vapor phase oxides occurs, then the weight change is more complicated to understand and the impact on the O{sub 2} concentration cannot be unravelled. Furthermore, it turns out that O{sub 2}-scavenging by the mesh affects the amount of O{sub 2} that is available to react with the coal sample. It was concluded that it is only possible to conduct reliable tests under conditions which the favor the formation of solid MoO{sub 2} only, as this leads to a quantifiable weight gain. Its impact can then be accounted for in the evaluation of the experimental weight change. In the case of MoO{sub 2} formation, the impact of the mesh oxidation on the amount of O{sub 2} available to react with the sample can also be estimated. It has been found that the wire-mesh reactor, equipped with the trapped air injection system, can be used to obtain valid data at up to 1600{sup o} C and 0.5 MPa. This pressure is similar to that of the blast-furnace raceway, but the temperature is several hundred degrees lower. However, preliminary tests have shown that useful kinetic data on the extents of reaction can be obtained with the equipment, provided it is operated under conditions that minimize the formation of vapor phase Mo oxides. 18 refs., 13 figs., 3 tabs.

Long Wu; N. Paterson; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering

2006-12-15

383

Comportamento de tipos de escórias de siderurgia como corretivo da acidez do solo / Conduct of blast furnace slags on the correction of soil acidity  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Com a finalidade de verificar o comportamento de tipos de escórias da siderurgia nacional, na correção da acidez de solo argilo-arenoso do Terciário, foi instalado um ensaio comparando-as com o de um calcário dolomítico. Empregaram-se 6.000 quilogramas por hectare de todos os materiais estudados, em [...] canteiros mantidos com vegetação espontânea roçada, periòdicamente. Os resultados mostraram que o calcário dolomítico foi o mais eficiente, seguido pelas duas escórias. Estas mostraram-se, também, eficientes no contrôle à acidez, mas sem diferenças significativas entre si. Abstract in english With the purpose to examine the behavior of two types of blast furnace slags in the combat against soil acidity, a test was installed comparing them with a dolomitic limestone. This test was established in soil of the Pinda series, at the Experiment Station of the Departamento da Produção Animal, in [...] the Pindamonhangaba county, Paraiba River valley, during a 23-mouths period. Six thousand kilograms per hectare of all the materials studied were utilized and the ploots were kept without cultivation, being cleaned periodically of the natural vegetation. The results obtained showed that the limestone was the most efficient, followed by the two types of scoria with no difference between them revealing themselves also efficient in the control of acidity.

A. Gentil, Gomes; Hermano, Gargantini; H. Garcia, Blanco.

384

Resistencia a los cloruros en el concreto adicionado con escoria de alto horno / Resistance to chloride in the additioned concrete with blast furnace slag  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish Para evaluar la resistencia a los cloruros en diferentes mezclas de concreto se realizó el ensayo de permeabilidad rápida a cloruros, estipulado en la norma ASTM 1202 [1]. Para ello se utilizó un equipo hecho en el país que sigue los requerimientos dados por esta norma. Se ensayaro [...] n concretos con 6 diferentes relaciones agua/cementante (a/c) y tres porcentajes de adición de escoria en reemplazo de parte del cemento. Aunque la edad a la que se evaluaron las muestras de concreto fue la misma, también se varió el tiempo de saturación de las muestras en agua. Abstract in english For determining the chloride resistance of different concrete samples, the rapid chloride permeability test was used. This procedure has been established in the standard test method ASTM 1202 [1] For this purpose, national equipment was used. It follows the specifications of the me [...] thod. The tested concretes had 6 different water/binder ratios (w/b) and three percentages of blast-furnace slag as a replacement of part of cement. Although the age of the concrete was the same in all the cases, the time of saturation in water was different.

Naliett Karina, Santamaría Díaz; Luis Eduardo, Yamín Lacouture; Carlos Alberto, Arcila López.

385

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)

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.

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

386

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

387

Improvement of ground granulated blast furnace slag on stabilization/solidification of simulated mercury-doped wastes in chemically bonded phosphate ceramics.  

Science.gov (United States)

This paper investigated the effectiveness of (ground granulated blast furnace slag) GGBFS-added chemically bonded phosphate ceramic (CBPC) matrix on the stabilization/solidification (S/S) of mercury chloride and simulated mercury-bearing light bulbs (SMLB). The results showed that the maximal compressive strength was achieved when 15% and 10% ground GGBFS was added for HgCl(2)-doped and SMLB-doped CBPC matrices, respectively. The S/S performances of GGBFS-added matrices were significantly better than non-additive matrices. As pore size was reduced, the leaching concentration of Hg(2+) from GGBFS-added CBPC matrix could be reduced from 697 microg/L to about 3 microg/L when treating HgCl(2). Meanwhile, the main hydrating product of GGBFS-added matrices was still MgKPO(4).6H(2)O. The improvement of S/S effectiveness was mainly due to physical filling of fine GGBFS particles and microencapsulation of chemical cementing gel. PMID:18289781

Liu, Zhongzhe; Qian, Guangren; Zhou, Jizhi; Li, Chuanhua; Xu, Yunfeng; Qin, Zhe

2008-08-30

388

Proceedings of the 36. McMaster University symposium on iron and steel making : the challenges of coal injection in today's blast furnaces  

Energy Technology Data Exchange (ETDEWEB)

The Steel Research Centre (SRC) at McMaster University develops exploitable technologies that benefit the steel industry. There are 3 components to the SRC's mission, notably to conduct research leading to commercially relevant new approaches to ironmaking, steelmaking process control, waste processing, steel product design and metal forming technologies; provide training of highly qualified personnel as a the means of transferring new technology to the steel industry; and provide continuing education for steel industry engineers. This conference was attended by the world's major steel producers, as well as suppliers and engineering consultants to the industry. The conference was a discussion-oriented forum in which manufacturers and technical personnel discussed major aspects of blast furnace ironmaking, such as energy balance; current operations and optimization; opportunities to use excess energy; utilities management; purchased energy; and derivative gases. The symposium featured 14 presentations, of which 9 have been catalogued separately for inclusion in this database. The discussions following each presentation were also included in the proceedings. refs., tabs., figs.

Irons, G.A. (ed.) [McMaster Univ., Hamilton, ON (Canada). Dept. of Engineering, Steel Research Centre; Donaldson, B. (comp.) [ArcelorMittal Dofasco, Hamilton, ON (Canada); Ricketts, J. (comp.) [ArcelorMittal Steel USA, Chicago, IL (United States); Hutchinson, S.; Entwistle, J. (comps.) [US Steel Canada, Hamilton, ON (Canada)

2008-07-01

389

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)

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.

Dawei Zhao

2014-05-01

390

Hopewell Furnace National Historic Site. Teacher's Guide.  

Science.gov (United States)

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.…

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

391

A furnace  

Energy Technology Data Exchange (ETDEWEB)

A furnace is presented for burning solid lumpy fuel in a fluidized bed which can be used in boilers. The furnace contains a vertical chamber supplied with a gas-distributing network. In the upper part of the chamber, tangential secondary air-blast nozzles are placed at a downards angle. A flue is also placed there and is connected using openings for diverting the gases to a chamber. In order to lessen fuel loss with the carrying-out activity, the flue is placed in chamber 2, preferably in line with the chamber's axis, and the openings are made in its lateral walls. The secondary air-blast nozzles are placed below the openings which are supplied with lateral baffle plates directed towards the same side as the tangential nozzles. In other variations (there are 4 in all) the nozzles can be located on the lateral walls of the flue, on the lateral walls of the chamber, in the chamber space and on the upper wall of the chamber. In the first, second and third variations, the nozzles are located below the openings. Effective fuel combustion takes place on a grill. It is inadvisable to burn the soft particles of the fuel to be carried away upwards towards the top of the chamber where they are returned to the lateral walls of the chamber under the influence of the gas eddy formed by currents of air from the nozzles--and where they slide onto the grill and burn out on it. Placing the flue along the axis of the chamber ensures an effective twist in the gas eddy which facilitates increasing particle separation just as it facilitates the performance of the openings on the lateral walls of the flue, i.e., in the area in which the particles are least concentrated. It also ensures complete separation due to the pronounced deflection in the gas current.

Mariamchik, I.I.; Fursov, I.D.; Mariamchik, M.I.; Pavlov, N.V.

1980-05-25

392

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)

Full Text Available SciELO Brazil | Language: Spanish Abstract in spanish 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 res