scholarly journals Effect of oxygen potential and fluxing components on phase relations during sintering of iron ore

2010 ◽  
Vol 46 (2) ◽  
pp. 123-130 ◽  
Author(s):  
F. Kongoli ◽  
I. Mcbow ◽  
R. Budd ◽  
S. Llubani ◽  
A. Yazawa
Keyword(s):  
Blast Furnace ◽  
Oxygen Potential ◽  
Raw Materials ◽  
Optimal Operation ◽  
Phase Relations ◽  
Care Needs ◽  
State Reduction ◽  
Effect Of Oxygen ◽  
Solid State Reduction ◽  
Sintering Processes

The optimal operation of the blast furnace depends considerably on the properties of the sinter fed into the furnace. As a result, the optimization of the sintering processes has a direct effect on the overall effectiveness of the iron making processes. In order to produce a good sinter special care needs to be taken in order to assure it has a good permeability and reducibility and it is able to retain these properties for a certain time. If the sinter starts to melt down early in the upper part of the blast furnace, where its solid state reduction is essential, permeability decreases, the gas channels get blocked, reductibility diminishes and serious problems may also follow. Among the factors that influences the above mentioned sinter properties are the oxygen potential and fluxing components. Nevertheless, their effect on the phase relations during sintering and sinter reduction conditions has not yet entirely clarified and confusion exists in literature. This quantification becomes even more important today where many new minor components such as Al2O3 and MgO enter the sinter through raw materials. This work quantifies the effect of oxygen potential and fluxing components such as alumina and magnesia on the liquidus and phase relations of the sinter primary melts in the iron rich portion of CaO-FeO-Fe2O3-SiO2 system at sintering conditions. This is carried out by the means of new type of industrial diagrams in the form of Fe/CaO vs. SiO2 that can directly help the optimization of the sintering processes.

scholarly journals Measurement of Temperature Dependent Dielectric Constant of Coal Samples for Burden Surface Profiling at Blast Furnace

2021 ◽  
Vol 4 (2) ◽  
pp. 38-51
Author(s):  
Chitresh Kundu ◽  
Prabal Patra ◽  
Bipan Tudu ◽  
Dibyayan Patra
Keyword(s):  
Dielectric Constant ◽  
Blast Furnace ◽  
Electromagnetic Waves ◽  
Raw Materials ◽  
Steel Production ◽  
Cavity Resonator ◽  
Optimal Operation ◽  
Profile Measurement ◽  
Blast Furnaces ◽  
Iron And Steel

Blast furnaces (BFs) are the key receptacles of iron and steel smelting. Iron ore, coke and limestone are some of the raw materials that are used in the process of iron making and the charging operation needs to be accomplished by accurately estimating the current depth of the burden surface. To accomplish the goal of global class steel production, burden profile measurement and monitoring is vital. This measuring and monitoring help in augmenting the best usage of charge materials and energy consumptions. Radar based measurement is best for determine the level and profile of the burden inside the furnace. However, for the optimal operation of the radar, it is important know the dielectric constant of the material. There are many approaches to determine the dielectric constant like capacitive methods, transmission line methods, cavity resonator methods, open cavity methods and so on. For this study the cavity resonator method is has been used for measuring the permittivity of coal samples. The reflection capability of electromagnetic waves by coal is a function of its dielectric properties which is also has a dependency on temperature. The results presented in this paper will provide essential design input for radar-based measurements at blast furnace, especially for burden profiling at blast furnaces.

“In-Situ Raman Spectroscopy of Electronic Processes in Fullerene Thin Films

2002 ◽  
Vol 725 ◽  
Author(s):  
S.B. Phelan ◽  
B.S. O'Connell ◽  
G. Farrell ◽  
G. Chambers ◽  
H.J. Byrne
Keyword(s):  
Thin Film ◽  
Indium Tin Oxide ◽  
Low Temperatures ◽  
In Situ Raman Spectroscopy ◽  
State Reduction ◽  
In Situ Raman ◽  
Linear Behavior ◽  
Current Voltage ◽  
Solid State Reduction

AbstractThe current voltage characteristics of C60 thin film sandwich structures fabricated by vacuum deposition on indium tin oxide (ITO) with an aluminium top electrode are presented and discussed. A strongly non-linear behavior and a sharp increase in the device conductivity was observed at relatively low voltages (∼2V), at both room and low temperatures (20K). At room temperature the system is seen to collapse, and in situ Raman measurements indicate a solid state reduction of the fullerene thin film to form a polymeric state. The high conductivity state was seen to be stable at elevated voltages and low temperatures. This state is seen to be reversible with the application of high voltages. At these high voltages the C60 film was seen to sporadically emit white light at randomly localized points analogous to the much documented Electroluminescence in single crystals.

Experimental Research on the Qualitative Characteristics of Iron Ores and Ferrous Waste That Can Be Used in Blast Furnace Mixt Injection Technology

2019 ◽  
Vol 70 (11) ◽  
pp. 3835-3842
Author(s):  
Mihai Dumitru Tudor ◽  
Mircea Hritac ◽  
Nicolae Constantin ◽  
Mihai Butu ◽  
Valeriu Rucai ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Experimental Research ◽  
Raw Materials ◽  
Coal Dust ◽  
Production Costs ◽  
Iron Ores ◽  
Fine Grained ◽  
Experimental Laboratory ◽  
Injection Technology ◽  
Direct Use

Direct use of iron ores in blast furnaces, without prior sintering leads to a reduction in production costs and energy consumption [1,2]. Fine-grained iron ores and iron oxides from ferrous wastes can be used together with coal dust and limestone in mixed injection technology through the furnace tuyeres. In this paper are presented the results of experimental laboratory investigations for establishing the physic-chemical characteristics of fine materials (iron ore, limestone, pulverized coal) susceptible to be used for mixed injection in blast furnace. [1,4]. The results of the experimental research have shown that all the raw materials analyzed can be used for mixt injection in blast furnace.

Phase relations associated with the aluminum blast furnace: Aluminum oxycarbide melts and Al-C-X (X=Fe, Si) liquid alloys

1987 ◽  
Vol 18 (2) ◽  
pp. 433-444 ◽  
Author(s):  
Harumi Yokokawa ◽  
Masao Fujishige ◽  
Seiichi Ujiie ◽  
Masayuki Dokiya
Keyword(s):  
Blast Furnace ◽  
Phase Relations ◽  
Liquid Alloys

Adjustment of a technology of cast iron smelting in the blast furnace of jsc "ural steel" w ith a volume of 1232 см3 with charge h a v in g 95% share of Mikhailovskii GOK pellets

2021 ◽  
Vol 77 (7) ◽  
pp. 768-775
Author(s):  
I. F. Iskakov ◽  
G. A. Kunitsyn ◽  
D. V. Lazarev ◽  
А. А. Red`kin ◽  
S. A. Trubitsyn ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Iron Ore ◽  
Raw Materials ◽  
Raw Material ◽  
Material Base ◽  
Hot Metal ◽  
Charging System ◽  
Iron Smelting ◽  
Gas Consumption ◽  
A Charge

To use effectively internal raw material base, JSC “Ural Steel” accomplished I category major overhaul of the blast furnace No. 2. The main purpose of the overhaul was to design a rational profile which could ensure an ability to operate with a charge containing 95 % of Mikhailovskii GOK (mining and concentrating plant) pellets having basicity of 0.5 by CaO/SiO2. The blast furnace No. 2 having useful volume of 1232 m3, was constructed by design of Danieli Corus, the Netherlands, and was blown in on December 30, 2020. In the process of guarantee tests, step-by-step increase of Mikhailovskii GOK pellets (Fetotal = 60.5 %, CaO/SiO2 = 0.5) content in the charge iron ore part was being accomplished from 55 to 95.1%. Charging of the blend containing pellets in the amount of 55% of iron ore part, was done by charging system 4OOCC + 1COOCC (Ore - Coke) with filling level 1.5 m. Under conditions of pellets part increase in the blend, the charging system was changed to decrease their content at the periphery, to increase it in the ore ridge zone and make it intermediate between periphery and the ore ridge. At the pellets share in the iron ore raw materials 0.75 the charging system was used as the following: 3OOCC + 1COOC + 1COOCC, while at the content 95.1% the following charging system was used: 2COOC + 2COOC + 1COOCC. It was noted that in the period of guarantee tests the furnace running was smooth. The average silicon content in the hot metal was 0.70% at the standard deviation 0.666. Sulfur content in the hot metal did not exceed 0.024%, the blowing and natural gas consumption figures were 2100 m3/min and 11000 m3/min correspondently, oxygen content in the blowing 26.5%, hot blowing and top smoke pressure figures were 226.5 and 109.8 KPa correspondently. The productivity of the furnace was reached as high as 2358 t/day at the specific coke rate 433 kg/t of hot metal. After guarantee tests completion, the pellets content in the iron ore part was decreased gradually from 95 down to 50%. The decreasing was made by 5% in every 6 hours of operation. Application of the mastered technology of the blast furnace No. 2 with the increased share of pellets will enable to stably supply the blast furnaces No. 1, 3 and 4 by iron ore raw materials in the proportion of 30-35% of pellets and 65-70% of sinter.

scholarly journals Properties and application of carbon composite brick for blast furnace hearth

2015 ◽  
Vol 51 (2) ◽  
pp. 143-151 ◽  
Author(s):  
K.X. Jiao ◽  
J.L. Zhang ◽  
Z.J. Liu ◽  
Y.G. Zhao ◽  
X.M. Hou
Keyword(s):  
Blast Furnace ◽  
Chemical Composition ◽  
Raw Materials ◽  
Protective Layer ◽  
Silicon Powder ◽  
Slag Layer ◽  
Carbon Composite ◽  
Carbon Layer ◽  
Furnace Hearth ◽  
Blast Furnace Hearth

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

scholarly journals Fundamental Investigation for Processing of Pb-Cu-S-Bearing Materials

Metals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 74
Author(s):  
Christoph Zschiesche ◽  
Jürgen Antrekowitsch
Keyword(s):  
Oxygen Potential ◽  
Lead Concentration ◽  
Raw Materials ◽  
Research Work ◽  
Distribution Coefficients ◽  
Condensed Phases ◽  
Fundamental Investigation ◽  
Bearing Materials ◽  
The Right ◽  
The Impact

The processing of polymetallic materials provides some challenges to every flowsheet. Within Aurubis Cu-Pb-metallurgical flowsheet, a broad range of raw materials and intermediates are processed. Continuous improvements are required to adapt the flowsheet according to the changing material quantity and quality. Therefore, thermodynamic modeling is the desired and most efficient way to conduct scenario analysis. Hence, databases and software are becoming better and better as the acceptance of this method increased. Further understanding is promoted by conducting experimental test work to validate the calculated results. In this research work, the impact of various oxygen potential on the formation of the condensed phases’ slag, matte, speiss and crude lead were investigated. A frequent check of slag metallurgy, in particular, the iron and lead concentration, provide feedback if the metallurgical process is operating at the right oxygen potential. Following, the calculated distribution coefficients for Cu, Pb, As, Sb, Sn and Ni between matte/speiss and speiss/lead are discussed.

scholarly journals Feasibility of nickel extraction from Indian chromite overburden by solid state reduction and smelting route

2020 ◽  
Vol 56 (2) ◽  
pp. 229-235
Author(s):  
P. Ganesh ◽  
Dishwar Kumar ◽  
S. Agrawal ◽  
Mandal Kumar ◽  
N. Sahu ◽  
...  
Keyword(s):  
Solid State ◽  
Horizontal Tube ◽  
Low Grade ◽  
State Reduction ◽  
Nickel Extraction ◽  
Reducing Atmosphere ◽  
Chromite Overburden ◽  
Solid State Reduction ◽  
Horizontal Tube Furnace ◽  
Direct Smelting

The present work demonstrates the extraction of nickel from low-grade chromite overburden by using solid state reduction and direct smelting route. Goethite & Quartz are present as major phases whereas chromite, hematite were identified as minor phases in the mineral. Solid state reduction of pellets were carried out inside a horizontal tube furnace at 1000?C, 1200?C, 1400?C for 30, 60, 90 and 120 minutes respectively with creating reducing atmosphere. Pellets of varying basicity (i.e. 0.5, 0.6, 0.7, 0.8 and 0.9) were used directly in the EAF for smelting studies. Highest percent of nickel (2%) having ~ 91% recovery were obtained in solid state reduction route for pellets which was reduced at 1400?C for 120 minute. Similar recovery (~90%) of nickel was obtained inside the ingot (0.67% Ni ) by using pellets of 0.9 basicity through smelting route. From the present investigation, it could be concluded that the solid state reduction as well as smelting routes are feasible for the recovery of nickel from low grade chromite overburden. The production of nickel pig (low grade ferronickel) could also be feasible by smelting route.

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