WU Sheng-li
,
FU Chang-liang
,
LIU Cheng-song
,
XU Jian
,
KOU Ming-yin
钢铁研究学报(英文版)
The mathematical model of minimum safety factor that investigated the collapse trends of coke layer under different charging parameters was established firstly on the basis of the slope stabilization theory in soil mechanics, and then the model of burden profile after coke collapse was improved by adopting the predetermination of quadratic curve and energy correction methods. The research will provide theoretical evidences for describing the coke profile more accurately and technical direction for choosing suitable charging parameters of blast furnace. The results show that: it is helpful to improve the stability of coke layer with increasing chute inclining angle and length of the coke flat; when the main falling point of ore moves toward furnace wall or the coke flat is wider, the curve radian of burden profile after coke collapse becomes smaller; the ore to coke ratio distribution agrees with the gas top temperature measurement well under considering coke collapse comparing with the result of ignoring coke collapse.
关键词:
blast furnace
,
coke layer stability
,
safety factor
,
coke collapse
,
burden profile
WU Sheng-li
,
LIU Cheng-song
,
FU Chang-liang
,
XU Jian
,
KOU Ming-yin
钢铁研究学报(英文版)
On the basis of the existing originally modified calculation models of theoretical combustion temperature (TCT), some factors, such as the combustion ratio of pulverized coal injection (PCI), the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment, were amended and improved to put forward a more comprehensive model for calculating TCT. The influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model, which showed that the present model could reflect the thermal state of a hearth more effectively.
关键词:
blast furnace
,
theoretical combustion temperature
,
improved calculation model
Dauter Oliveira
,
WU Sheng-li
,
DAI Yu-ming
,
XU Jian
,
CHEN Hong
钢铁研究学报(英文版)
In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores from China, Brazil and Australia. Furthermore, several indices were defined to evaluate sintering properties of iron ores. The results show that: for chemical composition, Brazilian ores present high TFe, low SiO2, and low Al2O3 content. For granulation, particle diameter ratio of Brazilian ores are high; particle intermediate fraction of Chinese concentrates are low; and average particle size and clay type index of Australian ores are high. For high-temperature properties, ores from China, Brazil and Australia present different characteristics. Ores from different origins should be mixed together to obtain good high-temperature properties. According to the analysis of each ore′s sintering properties, an ore blending scheme (Chinese concentrates 20%+Brazilian ores 40%+Australian ores 40%) was suggested. Moreover, sinter pot test using blending mix was performed, and the results indicated that the ore blending scheme led to good sintering performance and sinter quality.
关键词:
sintering
,
iron ore
,
sintering property indices
,
ore blending scheme
CAO Yong-guo
,
WU Sheng-li
,
HAN Hong-liang
,
WANG Hong-wei
,
XUE Fang
,
LIU Xiao-qin
钢铁研究学报(英文版)
Pilbara blending iron ore powder (PB powder) is blending ores with good and poor quality iron ores, so how to use PB power effectively is a problem. The self-characteristics of PB powder and its single-components were studied respectively, such as the macroscopic properties, microscopic properties, and high-temperature properties; the behavior and effect in the sintering were mastered. Then based on the new ore-proportioning idea of iron ores sintering characteristics complementary, the principles on the effective use of PB powder were discussed, and was further validated through the sintering pot test and industrial production. The results show that: PB powder is composed of three kinds of iron ore, and the sintering characteristics of different iron ores are obviously discrepant. With the ore-proportioning optimization based on the iron ores sintering characteristics complementary, the proportion of PB iron ore powder can be increased to more than 45%.
关键词:
Pilbara blending ore
,
sintering
,
mixed state
,
high effective utilization
WU Sheng-li
,
LIU Xiao-qin
,
ZHOU Qi
,
XU Jian
,
LIU Cheng-song
钢铁研究学报(英文版)
The reduction degradation characteristics of typical sinter, pellet and lump ore were tested with the reducing gas conditions simulating two kinds of iron-making processes. The results show that, in the same condition of gas composition and temperature, the reduction degradation degree (RDI＜3.15 mm) of sinter is high, RDI＜3.15 mm of lump ore is low and RDI＜3.15 mm of pellet is in the middle level. With two kinds of gas composition simulating different iron-making processes, the reduction degradation indices (RDI) of three kinds of iron ores all present the tendency of “inverted V-shape” in the temperature range from 450 to 650 ℃, and the RDI reach the maximum value at 550 ℃. The reduction degradation degrees of iron ores are extended when mixing the gas with hydrogen to increase the reduction potential, and the influence extent is discrepant for different iron ores. Colligating the increase amplitude of grains in small size fraction, the influence of reducing gas on lump ore is the greatest, the influence on sinter is the second, and the sensitivity of pellet on the reducing gas properties change is relatively small. As for the degradation form, lump ore and sinter both present the degradation of cracking, and the distribution of small grains generated from the cracking is in the range from 0.5 to 6.3 mm uniformly. The lump ore presents surface cracking, while sinter presents integral cracking. The pellet presents the degradation of surface stripping, and the proportion of grains smaller than 0.5 mm is the highest, which is up to 90% in the grains smaller than 3.15 mm.
关键词:
sinter
,
pellet
,
lump ore
,
low temperature reduction degradation characteristic
,
gas property
