MgO addition plays a vital role in improving the quality of pellets. In this study, the effects of MgO addition on the compressive strength, reducibility, reduction swelling characteristics and softening-melting performance of V-Ti pellets were explored systematically with simulating BF conditions. From the results, it can be observed that the compressive strength decreased with increasing MgO due to the formation of magnesioferrite, the restriction of recrystallization-agglomeration of haematite and the decreasing of molten slag. The reducibility of V-Ti pellets improved substantially due to the increase of the porosity. The decreasing of RSI is mainly caused by the decreasing of lattice volume swelling during the transition from MgO·Fe2O3 to (Mg,Fe)O. In addition, the softening-melting behavior and permeability of V-Ti pellets packed bed was found to be improved with increasing MgO content. In sum, the V-Ti pellets with a MgO content higher than 2.4% exhibits optimum metallurgical properties.
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References
1.
Paunova:R.Thermodynamic study of the reduction of titanium magnetite concentrate with solid carbon. Metall Mater Trans B. 2002;33B:633–638. doi: 10.1007/s11663-002-0043-0
2.
TangJChuMSFengCet al.Melting separation process of high chromium vanadium-bearing titanomagnetite metallized pellet and its optimization by multi-index synthetic weighted scoring method. ISIJ Int. 2017;57:1156–1165. doi: 10.2355/isijinternational.ISIJINT-2016-714
3.
LiuZGChuMSWangHTet al.Effect of MgO content in sinter on the softening–melting behavior of mixed burden made from chromium-bearing vanadium–titanium magnetite. Int J Miner Metall Mater.2016;23:25–32. doi: 10.1007/s12613-016-1207-2
4.
ZhangGMFengKQYueHF.Theoretical analyses and experimental investigations of selective carbothermal reactions of vanadium-bearing titanomagnetite concentrates for preparation of iron-based wear-resistant material. JOM. 2016;68:2525–2532. doi: 10.1007/s11837-016-2035-6
5.
ManshadiADManuelJHapugodaSet al.Sintering characteristics of titanium containing iron ores. ISIJ Int.2014;54:2189–2195. doi: 10.2355/isijinternational.54.2189
6.
ZhaoWWangHTLiuZGet al.Preparation and optimization of vanadium titanomagnetite carbon composite hot briquette: A new type of blast furnace burden. JOM. 2017;69:1737–1744. doi: 10.1007/s11837-017-2359-x
YadavUSPandeyBDDasBKet al.Influence of magnesia on sintering characteristics of iron ore. Ironmak Steelmak. 2002;29:91–95. doi: 10.1179/030192302225002018
InazumiTShinadaKKawabeM.Influence of mineralogical characteristic of hematite in self-fluxed sinter on its degradation during the reduction. Tetsu-to-Hagané. 1982;68:2207–2214. doi: 10.2355/tetsutohagane1955.68.15_2207
11.
SakamotoNFukuyoHIwataYet al.Mineralogical study on degradation of sinter structure at low temperature reduction. Tetsu-to-Hagané. 1984;70:512–519. doi: 10.2355/tetsutohagane1955.70.6_512
12.
HsiehLHWhitemanJA.Effect of Raw material composition on the mineral phases in lime-fluxed iron ore sinter. ISIJ Int1993;33:462–473. doi: 10.2355/isijinternational.33.462
13.
LuLHolmesRJManuelJR.Effects of alumina on sintering performance of hematite iron ores. ISIJ Int2007;47:349–358. doi: 10.2355/isijinternational.47.349
14.
LiGHTangZKZhangYBet al.Reduction swelling behaviour of haematite/magnetite agglomerates with addition of MgO and CaO. Ironmak Steelmak. 2010;37:393–397. doi: 10.1179/030192310X12690127076352
15.
UmadeviTBrahmacharyuluASahRet al.Optimisation of MgO addition in low and high silica iron ore sinter to improve sinter reducibility at JSW steel limited. Ironmak Steelmak. 2014;41:270–278. doi: 10.1179/1743281213Y.0000000124
16.
DwarapudiSGhoshTKShankarAet al.Effect of pellet basicity and MgO content on the quality and microstructure of hematite pellets. Int J Miner Process2011;99:43–53. doi: 10.1016/j.minpro.2011.03.004
17.
DwarapudiSGhoshTKTathavadkarVet al.Effect of MgO in the form of magnesite on the quality and microstructure of hematite pellets. Int J Miner Process2012;112–113:55–62. doi: 10.1016/j.minpro.2012.06.006
18.
SembergPRutqvistAAnderssonCet al.Interaction between iron oxides and olivine in magnetite based pellets during reduction at temperatures below 1000°C. Ironmak Steelmak. 2011;38:321–328. doi: 10.1179/1743281210Y.0000000012
19.
SembergPAnderssonCBjörkmanB.Interaction between iron oxides and olivine in magnetite pellets during reduction to Wustite at temperatures of 1000–1300°C. ISIJ Int2013;53:391–398. doi: 10.2355/isijinternational.53.391
20.
MerajMPramanikSPalJ.Role of MgO and its different minerals on properties of iron Ore pellet. Trans Indian Inst Met. 2016;69:1141–1153. doi: 10.1007/s12666-015-0676-8
21.
ZhaoWWangHTChuMSet al.Investigation of reduction mechanism and kinetics of vanadium titanomagnetite carbon composite hot briquette at 1173 - 1373 K. Steel Res Int. 2017;88:1–9.
22.
DwarapudiSBanerjeePKChaudharyPet al.Effect of fluxing agents on the swelling behavior of hematite pellets. Int J Miner Process2014;126:76–89. doi: 10.1016/j.minpro.2013.11.012
23.
ChengGJXueXXJiangTet al.Effect of TiO2 on the crushing strength and smelting mechanism of high-chromium vanadium-titanium magnetite pellets. Mater Trans B. 2016;47B:1713–1726. doi: 10.1007/s11663-016-0628-7
24.
ChuMS.Raw fuels and auxiliary materials in ferrous metallurgy. 1st ed.Beijing: Metallurgical Industry Press; 2010; 158–162.
