An in-depth study of the consolidation behaviour of high-silica fluxed pellets will help promote the development of a high-proportion pellet smelting process suitable for China’s resource structure. Lime, slaked lime, and limestone were used as calcium-containing additives to prepare high-silica fluxed pellets, and the suitable calcium-containing additives were lime and limestone. Compared with acid pellets, the suitable preheating temperature of high-silica fluxed pellets is higher (1100°C). The phase transformation during preheating consists mainly of the thermal decomposition of CaCO3 and Ca (OH)2 and the reaction between the solid phases.The roasting temperature of high-silica fluxed pellets should be controlled within a small range (1250°C–1280°C). The phase transition during the roasting of mainly lies in the generation and migration of the liquid phase. The Fe2O3 consolidation, the pore distribution law, and the liquid phase formation jointly determine the consolidation properties of the pellet.
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References
1.
ZhaoJZuoHWangYet al.Review of green and low-carbon ironmaking technology. Ironmak Steelmak. 2020;47:296–306.
2.
UedaS.Preface to the special issue on ‘Development of Technologies for the Low Carbon Ironmaking’. ISIJ Int. 2015;55:1145.
3.
ChenTLiangLTangSet al.A case study on large-scale grate-kiln production of fluxed iron oxide pellets: Zhanjiang pelletizing plant of BaoSteel. Miner Process Extr Metall Rev. 2019;40:123–128.
4.
ZhangYChenXSuZet al.Improving properties of fluxed iron ore pellets with high-silica by regulating liquid phase. J Iron Steel Res Int. 2021;29:1381–1392.
5.
BaiKLiuLPanYet al.A review: research progress of flux pellets and their application in China. Ironmak Steelmak. 2021;48:1048–1063.
6.
FirthAR.Interactions among magnetite oxidation, calcination of carbonate minerals and melt formation in iron ore pellets. Miner Process Extr Metall Rev. 2013;116:93–100.
7.
FirthARGardenJF.Interactions between magnetite oxidation and flux calcination during iron ore pellet induration. Metall Mater Trans B. 2008;39:524–533.
8.
FirthARGardenJFDouglasJD.Phase equilibria and slag formation in the magnetite core of fluxed iron ore pellets. ISIJ Int. 2008;48:1485–1492.
9.
DwarapudiSGhoshTKShankarAet al.Effect of pyroxenite flux on the quality and microstructure of hematite pellets. Int J Miner Process. 2010;96:45–53.
10.
DwarapudiSSekharCPaulIet al.Effect of fluxing agents on reduction degradation behaviour of hematite pellets. Ironmak Steelmak. 2016;43:180–191.
11.
PrustiPBarikKDashNet al.Effect of limestone and dolomite flux on the quality of pellets using high LOI iron ore. Powder Technol. 2021;379:154–164.
12.
FanXGanMJiangTet al.Influence of flux additives on iron ore oxidized pellets. J Cent South Univ. 2010;17:732–737.
13.
ZhuDYangCPanJet al.Insight into the consolidation mechanism of oxidized pellets made from the mixture of magnetite and chromite concentrates. Metall Mater Trans B. 2015;47:1010–1023.
14.
QingGWuKDuXet al.Miner Process Extr Metall Rev. 2019;128:213–220.
15.
JiangTZhangYBHuangZCet al.Preheating and roasting characteristics of hematite–magnetite (H–M) concentrate pellets. Ironmak Steelmak. 2008;35:21–26.
16.
SembergPRutqvistAAnderssonCet al.Interactions between iron oxides and the additives quartzite, calcite and olivine in magnetite based pellets. ISIJ Int. 2011;51:173–180.
17.
WangYZhangJLiuZ.Mineralogical characteristics and isothermal oxidation kinetics of ironsand pellets. Metals. 2019;9:265.
18.
SlatteryJCBirdRB.Calculation of the diffusion coefficient of dilute gases and of the self-diffusion coefficient of dense gases. AIChE J. 1958;4:137–142.
19.
BartelsWJHornstraJLobeekDJW.X-ray diffraction of multilayers and superlattices. Acta Crystallogr A. 1986;42:539–545.
20.
YangCZhuDPanJet al.Oxidation and induration characteristics of pellets made from western Australian ultrafine magnetite concentrates and its utilization strategy. J Iron Steel Res Int. 2016;23:924–932.
21.
LiJAnHLiuWet al.Effect of basicity on metallurgical properties of magnesium fluxed pellets. J Iron Steel Res Int. 2020;27:239–247.
22.
LiuZChengQLiKet al.The interaction of nanoparticulate Fe2O3 in the sintering process: a molecular dynamics simulation. Powder Technol. 2020;367:97–104.
23.
GuoHShenFJiangHXet al.Effects of MgO additive on metallurgical properties of fluxed-pellet. J Cent South Univ. 2019;26:3238–3251.
24.
IljanaMKemppainenAPaananenTet al.Effect of adding limestone on the metallurgical properties of iron ore pellets. Int J Miner Process. 2015;141:34–43.
25.
UmadeviTKumarPLoboNFet al.Influence of pellet basicity (CaO/SiO2) on iron ore pellet properties and microstructure. ISIJ Int. 2011;51:14–20.
26.
LooCELeungW.Factors influencing the bonding phase structure of iron ore sinters. ISIJ Int. 2003;43:1393–1402.
27.
AbouzeidAZMKotbIMNegmAA.Iron ore fluxed pellets and their physical properties. Powder Technol. 1985;42:225–230.
28.
ZengRLiWWangNet al.Influence and mechanism of CaO on the oxidation induration of Hongge Vanadium Titanomagnetite Pellets. ISIJ Int. 2020;60:2199–2205.
29.
MarkCPhilippeB.Optimizing the operation of straight-grate iron-ore pellet induration systems using process models. Metall Mater Trans B. 1999;30:803–813.
30.
WangRZhangJLiuZet al.Effect of lime addition on the mineral structure and compressive strength of magnesium containing pellets. Powder Technol. 2020;376:222–228.
31.
FrielJJEricksonES.Chemistry, microstructure, and reduction characteristics of dolomite-fluxed magnetite pellets. Metall Mater Trans B. 1980;11:233.
