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Alexander S Brand - One of the best experts on this subject based on the ideXlab platform.
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A Review of the Influence of Steel Furnace Slag Type on the Properties of Cementitious Composites
Applied Sciences, 2020Co-Authors: Alexander S Brand, Ebenezer O FanijoAbstract:The type of steel furnace slag (SFS), including electric arc furnace (EAF) slag, basic oxygen furnace (BOF) slag, Ladle Metallurgy furnace (LMF) slag, and argon oxygen decarburization (AOD) slag, can significantly affect the composite properties when used as an aggregate or as a supplementary cementitious material in bound applications, such as concretes, mortars, alkali-activated materials, and stabilized soils. This review seeks to collate the findings from the literature to express the variability in material properties and to attempt to explain the source(s) of the variability. It was found that SFS composition and properties can be highly variable, including different compositions on the exterior and interior of a given SFS particle, which can affect bonding conditions and be one source of variability on composite properties. A suite of tests is proposed to better assess a given SFS stock for potential use in bound applications; at a minimum, the SFS should be evaluated for free CaO content, expansion potential, mineralogical composition, cementitious composite mechanical properties, and chemical composition with secondary tests, including cementitious composite durability properties, microstructural characterization, and free MgO content.
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stabilization of a clayey soil with Ladle Metallurgy furnace slag fines
Materials, 2020Co-Authors: Alexander S Brand, Punit Singhvi, Ebenezer O Fanijo, Erol TutumluerAbstract:The research study described in this paper investigated the potential to use steel furnace slag (SFS) as a stabilizing additive for clayey soils. Even though SFS has limited applications in civil engineering infrastructure due to the formation of deleterious expansion in the presence of water, the free CaO and free MgO contents allow for the SFS to be a potentially suitable candidate for clayey soil stabilization and improvement. In this investigation, a kaolinite clay was stabilized with 10% and 15% Ladle Metallurgy furnace (LMF) slag fines by weight. This experimental study also included testing of the SFS mixtures with the activator calcium chloride (CaCl2), which was hypothesized to accelerate the hydration of the dicalcium silicate phase in the SFS, but the results show that the addition of CaCl2 was not found to be effective. Relative to the unmodified clay, the unconfined compressive strength increased by 67% and 91% when 10% and 15% LMF slag were utilized, respectively. Likewise, the dynamic modulus increased by 212% and 221% by adding 10% and 15% LMF slag, respectively. Specifically, the LMF slag fines are posited to primarily contribute to a mechanical rather than chemical stabilization mechanism. Overall, these findings suggest the effective utilization of SFS as a soil stabilization admixture to overcome problems associated with dispersive soils, but further research is required.
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Interfacial transition zone of cement composites with steel furnace slag aggregates
Cement and Concrete Composites, 2018Co-Authors: Alexander S Brand, Jeffery R. RoeslerAbstract:Abstract As previous studies of mortar and concrete with steel furnace slag (SFS) aggregates have shown increases or decreases in the bulk mechanical properties, this study investigated the microstructural cause of these opposing trends through characterization of the interfacial transition zone (ITZ) with quantitative image analysis of backscatter electron micrographs. Three SFS types – basic oxygen furnace (BOF), electric arc furnace (EAF), EAF/Ladle Metallurgy furnace (EAF/LMF) – were examined as aggregates in a portland cement mortar. The ITZ size for all SFS mortar mixtures was similar, with the ITZ of BOF and EAF/LMF being slightly more porous than mortar mixtures with EAF or dolomite. Microstructural examinations of the SFS particle revealed that BOF and EAF/LMF aggregates have different outer and interior compositions, with the outer composition consisting of a porous layer, which likely contributes to the reduced strength relative to EAF. The imaging results demonstrated that the type of SFS and its spatial composition greatly influences the bulk properties of mortar and concrete, mainly as a function of porosity content in the ITZ and the outer layer and interior porosity of the SFS aggregate.
Bart Blanpain - One of the best experts on this subject based on the ideXlab platform.
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Ladle Metallurgy stainless steel slag as a raw material in ordinary portland cement production a possibility for industrial symbiosis
Journal of Cleaner Production, 2016Co-Authors: Remus Ion Iacobescu, G N Angelopoulos, Peter Tom Jones, Bart Blanpain, Yiannis PontikesAbstract:Abstract Ladle Metallurgy (LM) slag is generated during the refining process step in stainless steel making. In view of its very fine particle size, due to the transformation of β- to γ-C 2 S, and the Cr content, the slag is challenging in terms of handling and disposal and is used in only few applications. The current work explores the utilisation of the LM's fine fraction in Ordinary Portland Cement (OPC) clinker production. Three sets of samples containing LM slag, in 0 wt% (OPC – reference), 6 wt% (OPC6) and 14 wt% (OPC14), were investigated. The sintering temperature was 1450 °C with 40 min soaking time. The clinkers containing LM slag, showed a slight increase in C 3 S and a decrease in C 3 A and C 4 AF. The formation of the C 3 S initiated at a lower temperature probably due to the presence of F and C 2 S. Longer setting times were found for OPC6 and OPC14. The compressive strength results were found to be comparable at 2 d (22–25 MPa), 7 d (36–38 MPa) and 28 d (44 MPa) of curing, falling into 42.5R CEM I category. The emission of kgCO 2 /t of clinker during production, is estimated to decrease at least 12% for OPC14. A processing step for the pre-treatment of the slag is also presented, aiming to reduce the initial Cr content.
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Effect of mechanical activation on the hydraulic properties of stainless steel slags
Cement and Concrete Research, 2012Co-Authors: Lubica Kriskova, Peter Tom Jones, Yiannis Pontikes, Özlem Cizer, Gilles Mertens, Wout Veulemans, Daneel Geysen, Lucie Vandewalle, Koen Van Balen, Bart BlanpainAbstract:article i nfo This work aims to assess the possibility of using Ladle Metallurgy and argon oxygen decarburization stainless steel slag as a hydraulic binder after mechanical activation. Prolonged milling in ethanol suspension resulted in 10-fold increase of the surface area and increase of the amorphous phase. Calorimetric analysis of slags mixed with water indicated the occurrence of exothermic reactions. XRD results revealed that periclase, merwinite, γ-C2S and bredigite, decreased with hydration time. Thermogravimetric analyses indicated that the main hydration products are most probably C-S-H, CH and MH. The hydrated products in both slags were similar to C-S-H gel. WDS analysis demonstrated Ca and Si to be widespread in the structure. Formation of M-S-H gel or incorporation of Mg in the C-S-H gel remains uncertain. The 90 days compressive strength of mortars prepared from slags reached approximately 20% for LM and 10% for AOD of the compressive strength of mortars prepared from OPC.
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A morphological comparison between inclusions in aluminium killed steels and deposits in submerged entry nozzle
steel research international, 2003Co-Authors: Rob Dekkers, Bart Blanpain, P. Wollants, F Haers, B Gommers, C VercruyssenAbstract:A study was carried out to compare the inclusions present in low carbon aluminium killed (LCAK) steel with oxide particles in a clogging deposit formed during casting of LCAK steel. Steel pin samples were taken in the Ladle and in the tundish. It was observed that oxide particles in the clogging deposit are mainly coral-shaped clusters, dendritic clusters and irregular plates. From the comparison with inclusions in LCAK steel, it is concluded that the particles in the clogging deposits are formed during reoxidation of the steel, at least after the Ladle Metallurgy process and most probably in the submerged entry nozzle. They are not the result of sintering of small pre-existing inclusions.
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non metallic inclusions in aluminium killed steels
Ironmaking & Steelmaking, 2002Co-Authors: Rob Dekkers, Bart Blanpain, P. Wollants, F Haers, C Vercruyssen, B GommersAbstract:AbstractHeats of medium carbon aluminium killed, low carbon silicon-aluminium killed, and low carbon aluminium killed steels were sampled with short time intervals during Ladle Metallurgy. Non-metallic inclusions were extracted from the steel matrix and investigated using scanning electron microscopy and energy dispersive spectrometry. Six inclusion morphologies were recognised, i.e. spherical, faceted, platelike, and dendritic shapes, as well as clusters and aggregates. For each sample also the total oxygen content was measured. Spherical inclusions were most abundant, but clusters, aggregates, and large faceted inclusions made up most of the oxide volume fraction. The present research shows that clusters, which are formed during the deoxidation operation, are removed within ~15 min after aluminium addition. Aggregates and large polyhedra appear after 5-10 min and their sizes increase with holding time. Small, mainly spherical and polyhedral, and to some extent also platelike, inclusions do not show evol...
Yiannis Pontikes - One of the best experts on this subject based on the ideXlab platform.
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Ladle Metallurgy stainless steel slag as a raw material in ordinary portland cement production a possibility for industrial symbiosis
Journal of Cleaner Production, 2016Co-Authors: Remus Ion Iacobescu, G N Angelopoulos, Peter Tom Jones, Bart Blanpain, Yiannis PontikesAbstract:Abstract Ladle Metallurgy (LM) slag is generated during the refining process step in stainless steel making. In view of its very fine particle size, due to the transformation of β- to γ-C 2 S, and the Cr content, the slag is challenging in terms of handling and disposal and is used in only few applications. The current work explores the utilisation of the LM's fine fraction in Ordinary Portland Cement (OPC) clinker production. Three sets of samples containing LM slag, in 0 wt% (OPC – reference), 6 wt% (OPC6) and 14 wt% (OPC14), were investigated. The sintering temperature was 1450 °C with 40 min soaking time. The clinkers containing LM slag, showed a slight increase in C 3 S and a decrease in C 3 A and C 4 AF. The formation of the C 3 S initiated at a lower temperature probably due to the presence of F and C 2 S. Longer setting times were found for OPC6 and OPC14. The compressive strength results were found to be comparable at 2 d (22–25 MPa), 7 d (36–38 MPa) and 28 d (44 MPa) of curing, falling into 42.5R CEM I category. The emission of kgCO 2 /t of clinker during production, is estimated to decrease at least 12% for OPC14. A processing step for the pre-treatment of the slag is also presented, aiming to reduce the initial Cr content.
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Effect of mechanical activation on the hydraulic properties of stainless steel slags
Cement and Concrete Research, 2012Co-Authors: Lubica Kriskova, Peter Tom Jones, Yiannis Pontikes, Özlem Cizer, Gilles Mertens, Wout Veulemans, Daneel Geysen, Lucie Vandewalle, Koen Van Balen, Bart BlanpainAbstract:article i nfo This work aims to assess the possibility of using Ladle Metallurgy and argon oxygen decarburization stainless steel slag as a hydraulic binder after mechanical activation. Prolonged milling in ethanol suspension resulted in 10-fold increase of the surface area and increase of the amorphous phase. Calorimetric analysis of slags mixed with water indicated the occurrence of exothermic reactions. XRD results revealed that periclase, merwinite, γ-C2S and bredigite, decreased with hydration time. Thermogravimetric analyses indicated that the main hydration products are most probably C-S-H, CH and MH. The hydrated products in both slags were similar to C-S-H gel. WDS analysis demonstrated Ca and Si to be widespread in the structure. Formation of M-S-H gel or incorporation of Mg in the C-S-H gel remains uncertain. The 90 days compressive strength of mortars prepared from slags reached approximately 20% for LM and 10% for AOD of the compressive strength of mortars prepared from OPC.
Peter Tom Jones - One of the best experts on this subject based on the ideXlab platform.
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Ladle Metallurgy stainless steel slag as a raw material in ordinary portland cement production a possibility for industrial symbiosis
Journal of Cleaner Production, 2016Co-Authors: Remus Ion Iacobescu, G N Angelopoulos, Peter Tom Jones, Bart Blanpain, Yiannis PontikesAbstract:Abstract Ladle Metallurgy (LM) slag is generated during the refining process step in stainless steel making. In view of its very fine particle size, due to the transformation of β- to γ-C 2 S, and the Cr content, the slag is challenging in terms of handling and disposal and is used in only few applications. The current work explores the utilisation of the LM's fine fraction in Ordinary Portland Cement (OPC) clinker production. Three sets of samples containing LM slag, in 0 wt% (OPC – reference), 6 wt% (OPC6) and 14 wt% (OPC14), were investigated. The sintering temperature was 1450 °C with 40 min soaking time. The clinkers containing LM slag, showed a slight increase in C 3 S and a decrease in C 3 A and C 4 AF. The formation of the C 3 S initiated at a lower temperature probably due to the presence of F and C 2 S. Longer setting times were found for OPC6 and OPC14. The compressive strength results were found to be comparable at 2 d (22–25 MPa), 7 d (36–38 MPa) and 28 d (44 MPa) of curing, falling into 42.5R CEM I category. The emission of kgCO 2 /t of clinker during production, is estimated to decrease at least 12% for OPC14. A processing step for the pre-treatment of the slag is also presented, aiming to reduce the initial Cr content.
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Effect of mechanical activation on the hydraulic properties of stainless steel slags
Cement and Concrete Research, 2012Co-Authors: Lubica Kriskova, Peter Tom Jones, Yiannis Pontikes, Özlem Cizer, Gilles Mertens, Wout Veulemans, Daneel Geysen, Lucie Vandewalle, Koen Van Balen, Bart BlanpainAbstract:article i nfo This work aims to assess the possibility of using Ladle Metallurgy and argon oxygen decarburization stainless steel slag as a hydraulic binder after mechanical activation. Prolonged milling in ethanol suspension resulted in 10-fold increase of the surface area and increase of the amorphous phase. Calorimetric analysis of slags mixed with water indicated the occurrence of exothermic reactions. XRD results revealed that periclase, merwinite, γ-C2S and bredigite, decreased with hydration time. Thermogravimetric analyses indicated that the main hydration products are most probably C-S-H, CH and MH. The hydrated products in both slags were similar to C-S-H gel. WDS analysis demonstrated Ca and Si to be widespread in the structure. Formation of M-S-H gel or incorporation of Mg in the C-S-H gel remains uncertain. The 90 days compressive strength of mortars prepared from slags reached approximately 20% for LM and 10% for AOD of the compressive strength of mortars prepared from OPC.
Erol Tutumluer - One of the best experts on this subject based on the ideXlab platform.
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stabilization of a clayey soil with Ladle Metallurgy furnace slag fines
Materials, 2020Co-Authors: Alexander S Brand, Punit Singhvi, Ebenezer O Fanijo, Erol TutumluerAbstract:The research study described in this paper investigated the potential to use steel furnace slag (SFS) as a stabilizing additive for clayey soils. Even though SFS has limited applications in civil engineering infrastructure due to the formation of deleterious expansion in the presence of water, the free CaO and free MgO contents allow for the SFS to be a potentially suitable candidate for clayey soil stabilization and improvement. In this investigation, a kaolinite clay was stabilized with 10% and 15% Ladle Metallurgy furnace (LMF) slag fines by weight. This experimental study also included testing of the SFS mixtures with the activator calcium chloride (CaCl2), which was hypothesized to accelerate the hydration of the dicalcium silicate phase in the SFS, but the results show that the addition of CaCl2 was not found to be effective. Relative to the unmodified clay, the unconfined compressive strength increased by 67% and 91% when 10% and 15% LMF slag were utilized, respectively. Likewise, the dynamic modulus increased by 212% and 221% by adding 10% and 15% LMF slag, respectively. Specifically, the LMF slag fines are posited to primarily contribute to a mechanical rather than chemical stabilization mechanism. Overall, these findings suggest the effective utilization of SFS as a soil stabilization admixture to overcome problems associated with dispersive soils, but further research is required.
