Mechanism of growth of metallic phase in direct reduction of iron bearing oolites

1986 ◽  
Vol 17 (3) ◽  
pp. 433-442 ◽  
Author(s):  
S. Weissberger ◽  
Y. Zimmels ◽  
I. J. Lin
2018 ◽  
Vol 42 (3) ◽  
pp. 453-466
Author(s):  
Wei WANG ◽  
Pengfei YE ◽  
Xiaoli ZHOU ◽  
C WANG ◽  
Zekun HUO ◽  
...  

2010 ◽  
Vol 107 (5) ◽  
pp. 195-204 ◽  
Author(s):  
M. Vannucci ◽  
V. Colla ◽  
G. Corbo ◽  
S. Fera

2003 ◽  
Vol 67 (23) ◽  
pp. 4489-4503 ◽  
Author(s):  
Andrew L. Neal ◽  
Kevin M. Rosso ◽  
Gill G. Geesey ◽  
Yuri A. Gorby ◽  
Brenda J. Little

2020 ◽  
Vol 2,2020 (2,2020 (125)) ◽  
pp. 5-9
Author(s):  
Vaniukov A ◽  
Kovalyov D ◽  
Vaniukova N ◽  
Khodyko I ◽  
Bezshkurenko O

The objective of the present work is to research a quantitate ratio of degree direct reduction inside of SRP and degree of indirect reduction outside of SRP on the top of the blast furnace.The reactions of direct and indirect reduction occurring during the heat treatment of self reducing pellets (SRP) have been studied. In this investigation Blast furnace (BF) sludge which contains particles of coke, has been included in the SRP blend as a source of solid reductant and iron bearing oxides. In the SRP as a part ot the blast furnace burden occur the reactions simultaneously: inside of SRP-direct reduction by Csolid; gasification of carbon and indirect reduction by CO; and outside of SRP-indirect reduction of iron bearing oxides by reducing gas coming from the hearth of blast furnace through the column of charged materials. The experimental setup is shown in Fig. 1. It con-sists of a electrical heating furnace, which can be moved up and down. The quartz tube passes through the furnace. The reaction zone is in the middle of the furnace. Neutral argon atmosphere is created and for indirect reduction argon changed - on hydrogen. Gases of argon, hydrogen are introduced into the furnace separately. Wire of nickel alloy chromosome joins the scales test. A thermocouple is located in the tube.The crucible of wire chrome-nickel was permeable.Metohd. The experiments was performed continuously from the start temperature (~200 ˚C) to the experimental temperature (500 ˚C; 700 ˚C; 900 ˚C; 1100 ˚C) in argon free environment. Upon reaching the desired temperature argon was replaced by hydrogen during 30 minutes. After that the reduced probe of SRP was cooled in argon. Results. The integrated degree of reduction is equal 100%, which includes 98,6 % direct reduction by solid carbon under temperatures 1100°C. The chemical analysis of the reduced SRP showed the degree of integrated reduction change from 85,79 % (900 °C) to 92,50 % (1000 °C) and 84,6% (1100°C) and metallization 83,30 % (900 °C), 89,90 % (1000 °C), 80,75 % (1100 °C).These data correspond to results of degree of reduction SRP depends on temperature


2013 ◽  
Vol 40 (1) ◽  
pp. 61-68 ◽  
Author(s):  
P Rajput ◽  
B Bhoi ◽  
S Sahoo ◽  
R K Paramguru ◽  
B K Mishra

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 751 ◽  
Author(s):  
Zhiyuan Chen ◽  
Jie Dang ◽  
Xiaojun Hu ◽  
Hongyan Yan

Hydrogen has received much attention in the development of direct reduction of iron ores because hydrogen metallurgy is one of the effective methods to reduce CO2 emission in the iron and steel industry. In this study, the kinetic mechanism of reduction of hematite particles was studied in a hydrogen atmosphere. The phases and morphological transformation of hematite during the reduction were characterized using X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy. It was found that porous magnetite was formed, and the particles were degraded during the reduction. Finally, sintering of the reduced iron and wüstite retarded the reductive progress. The average activation energy was extracted to be 86.1 kJ/mol and 79.1 kJ/mol according to Flynn-Wall-Ozawa (FWO) and Starink methods, respectively. The reaction fraction dependent values of activation energy were suggested to be the result of multi-stage reactions during the reduction process. Furthermore, the variation of activation energy value was smoothed after heat treatment of hematite particles.


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