Recycling ladle furnace (LF) slag helps in sustainable steel making and reduces steel production costs. This paper focuses on recycling Si/Mn/Al-killed LF slag as a replacement for CaO–Al2O3-based synthetic slag for treating high carbon Si/Mn-killed steels. Characterization of different types of LF slag was carried out to identify chemical composition and mineralogical phases. Industrial trials were carried out by recycling LF slag along with lime and calcined bauxite as additives. The effect of recycled LF slag on the kinetics of desulphurization and other process parameters was studied and compared with regular practice. It was observed that LF slag can be recycled successfully as a replacement for CaO–Al2O3-based synthetic slag at an industrial scale.
Get full access to this article
View all access options for this article.
References
1.
VaranasiSSMoreVMRRaoMBVet al.Recycling ladle furnace slag as flux in steelmaking: a review. J Sustain Metall. 2019;5:449–462. DOI:10.1007/s40831-019-00243-9.
2.
HaratianM. The effect of calcium aluminates usage on Ladle refractory life. Proceedings ofAISTech – Iron and steel technology conference, Nashville (TN); USA; 2004
3.
VaranasiSSPathakRKSahooKKet al.Effect of CaO-Al2O3 based synthetic slag additions on desulphurisation kinetics of ladle furnace refining. Trans Indian Inst Met. 2019. DOI:10.1007/s12666-019-01616-0.
4.
VlcekJet al.Slags from steel production: properties and their utilization. Metalurgija. 2013;52(3):329–333. Available at: https://hrcak.srce.hr/95769.
5.
AminorroayaSEdrisHTohidiAet al. Recycling of ladle furnace slags. 2nd International Conference on Process Development in Iron and Steel making (SCANMET II). Sweden, MEFOS, 379–384; 2004
6.
SetiénJHernándezDGonzález JJ.Characterization of ladle furnace basic slag for use as a construction material. Constr Build Mater. 2009;23:1788–1794. DOI:10.1016/j.conbuildmat.2008.10.003.
7.
YangQTossavainenMEngstromFet al.Characteristics of steel slag under different cooling conditions. Waste Manage. 2015;27:1335–1344. DOI:10.1016/j.wasman.2006.08.002.
8.
NicolaeMVîlciuIManFZĂ. X-ray diffraction analysis of steel slag and blast furnace slag viewing their use for road construction. Sci Bull B Chem Mater Sci. 2007;69:100–108.
9.
BharatiSBasavarajaVMJagadeeshaRJet al.From waste to wealth: recycling the secondary resource from steel ladle as a flux in Si-killed steelmaking process. Ironmak Steelmak. 2018. DOI:10.1080/03019233.2018.1432251
10.
DahlinATillianderAErikssonJet al.Influence of ladle slag additions on BOF process performance. Ironmak Steelmak. 2012;39:378–385. DOI:10.1179/1743281211Y.0000000021.
11.
BeheraNRaddadiAAhmadSet al. Use of Al-killed ladle furnace slag in Si-killed steel process to reduce lime consumption improve slag fluidity. In Advances in molten slags fluxes and salts: Proceedings of the 10th International Conference on Molten Slags Fluxes and Salts; 2016. 1031–1039. DOI:10.1007/978-3-319-48769-4_110
12.
WangYYangSLiJet al.Cyclic use of ladle furnace refining slag for desulfurization. J Sus Metall. 2017;3:274–279. DOI:10.1007/s40831-016-0078-0.
13.
NzottaMMDuSSeetharamanS.Sulphide capacities in some multi component slag systems,1998. ISIJ Int; vol. 38:1170–1179. DOI:10.2355/isijinternational.38.1170
14.
YoshinoriTNobuoSSeshadriS.Sulphide capacities of CaO–Al2O3–SiO2–MgO–MnO slags in the temperature range 1673-1773. ISIJ Int. 2009;Vol. 49:156–163.
15.
DuffyJAIngramMD.Establishment of an optical scale for lewis basicity in inorganic oxyacids, molten salts, and glasses, 1971. J Am Chem Soc. 1971;93:6448–6454. DOI:10.1021/ja00753a019.
16.
MillsK. The estimation of slag properties, 2011. Short Course Presented as a Part of South African Pyrometallurgy. 2011.
17.
KondratievAJakE.Review of experimental data and modeling of the viscosities of fully liquid slags in the Al2O3-CaO-‘FeO’-SiO2 system. Metall Mater Trans B. 2001;32:1015–1025. DOI:10.1007/s11663-001-0090-y.
18.
PengchengYXiaolingGShuigenHet al.Desulphurisation of stainless steel by using CaO–Al2O3 based slags during secondary metallurgy. ISIJ Int. 2013;53:459–446.
19.
WagnerCMellgrenSWestbrookJH.Thermodynamics of alloys, Vol. 4. Cambridge: Addison-Wesley Press; 1952.
20.
OhtaHSuitoH.Activities of SiO2 and Al2O3 and activity coefficients of FeO and MnO in CaO-SiO2-Al2O3-MgO slags. Metallurgical and Materials Transactions B. 1998;Vol. 29:119–129.
21.
SighworthGKElliotJF.The thermodynamics of liquid dilute iron alloys. MetSci1974;8:298–310.
