Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other elements.If the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be ...Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other elements.If the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be used as a phosphate fertilizer.Phosphorus in converter slag is mainly enriched in 2CaO·SiO_(2)-3CaO·P_(2)O_(5)(C_(2)S-C_(3)P)solid solution and is easily dissolved in water.Therefore,acid leaching method was used to dissolve the solid solution to extract phosphorus in converter slag,so as to realize the recycling of phosphorus resources in converter slag.The leaching behavior of three actual converter slags from different steel mills in acid leaching solutions composed of citric acid,sodium hydroxide,hydrochloric acid and deionized water was studied by X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,Fourier transform infrared spectroscopy and Raman spectroscopy to reveal the change in object image structure as well as SiO_(4) and PO_(4) tetrahedron before and after acid leaching.The results show that only a small amount of phosphorus in converter slag with too low basicity is enriched in C_(2)S-C_(3)P solid solution,resulting in poor leaching effect.When the converter slag has a high basicity,the removal effect of phosphorus is 70.64%-81.88%.In addition,when the basicity of converter slag is roughly the same,the dephosphorization effect of slag with high FeO content is relatively poor.And acid leaching will cause depolymerization behavior of SiO_(4) and PO_(4) tetrahedron,so that the mole fraction of Q0(Si)(asymmetric stretching vibration of Si-O bond in SiO_(4) tetrahedron with bridge oxygen number of 0)and NBO/Si(non-bridging oxygen in silicate tetrahedra)will increase.Phosphate-containing solids can be obtained from the solution after acid leaching through static precipitation,and the solids have the potential to make phosphate fertilizers.展开更多
The rapid development of iron and steel metallurgy technology has promoted the continuous innovation and iteration of carbon-containing refractories for clean steel smelting.To meet the high-quality requirements for c...The rapid development of iron and steel metallurgy technology has promoted the continuous innovation and iteration of carbon-containing refractories for clean steel smelting.To meet the high-quality requirements for clean steel production and full exploit the performance advantages of carbon-containing refractories in dynamic smelting environment,it is necessary to explore the role of graphite and modified graphite in carbon-containing refractories.Based on this,graphite surface modification methods,including surfactants,surface oxidation,and surface coating,and their applications in carbon-containing refractories are reviewed.The advantages and disadvantages of each method are analyzed for practical use.Furthermore,combined with the existing problems,the application prospect of improved graphite in carbon-containing refractories is discussed.展开更多
This special issue is dedicated to the 3Oth anniversary of Journal of Iron and Steel Research International.In the past 30 years,Journal of Iron and Steel Research International has been focusing on the academic resea...This special issue is dedicated to the 3Oth anniversary of Journal of Iron and Steel Research International.In the past 30 years,Journal of Iron and Steel Research International has been focusing on the academic research and advancement in metallurgy and metallic materials.展开更多
The development of low-carbon refractories is of great significance,but it is limited by the deteriorated properties that resulted from the decreased graphite content.Incorporating composite powders has proved to be e...The development of low-carbon refractories is of great significance,but it is limited by the deteriorated properties that resulted from the decreased graphite content.Incorporating composite powders has proved to be effective in improving the properties of low-carbon refractories.The recent progress in the synthesis of composite powders including modified graphite,nanocarbon-containing composite powders,oxide/non-oxide and non-oxide composite powders and their applications in low-carbon refractories were reviewed,and the future development of composite powder technology was prospected.展开更多
The demand for low-carbon MgO–C refractories is ever growing to meet the development of advanced steelmaking technologies and efficient energy conservation.Meanwhile,to improve the oxidation resistance and inhibit th...The demand for low-carbon MgO–C refractories is ever growing to meet the development of advanced steelmaking technologies and efficient energy conservation.Meanwhile,to improve the oxidation resistance and inhibit the weakness of low-carbon MgO–C refractories,antioxidants are necessary.The application of ternary carbides that focused on improving the oxidation performance of MgO–C refractories has been explored,and the ternary carbides including Al_(4)O_(4)C,Al8B_(4)C_(7),Al_(4)SiC_(4),Ti_(2)AlC,Ti_(3)AlC_(2),and Ti_(3)SiC_(2)have been proved effective.The crystal structure,physical properties,oxidation behavior,and synthesis of these ternary carbides were summarized,and their oxidation mechanism in assisting antioxidation of MgO–C refractories was discussed.In addition,the potential aspects related to the usage and development of ternary carbides in low-carbon MgO–C refractories were proposed.展开更多
Al_(2)O_(3)-and MgO-based oxides are among the most common oxides in the steelmaking industry.They exist as the main components of refractories,inclusions,or slags.Al_(2)O_(3)-and MgO-based oxides interact with molten...Al_(2)O_(3)-and MgO-based oxides are among the most common oxides in the steelmaking industry.They exist as the main components of refractories,inclusions,or slags.Al_(2)O_(3)-and MgO-based oxides interact with molten slags continuously during the steel smelting process,which may lead to the dissolution and absorption of the oxides by molten slags,or reactions between oxides and molten slags to form intermediate products.Understanding the dissolution behavior of Al_(2)O_(3)-and MgO-based oxides in molten slags is important for prolonging the service life of refractories and removing inclusions in molten steel.Therefore,Al_(2)O_(3)-and MgO-based oxides are considered,and the test methods,dissolution mechanisms,and influencing factors are comprehensively introduced,which can provide a foundation for refractories wear and high-quality steel smelting.展开更多
BN–ZrO_(2)ceramics with different additives such as SiC,Al_(2)O_(3) and MgAl_(2)O_(4) were fabricated by hot pressing sintering process to study sintering properties and corrosion resistance by the rotary immersion m...BN–ZrO_(2)ceramics with different additives such as SiC,Al_(2)O_(3) and MgAl_(2)O_(4) were fabricated by hot pressing sintering process to study sintering properties and corrosion resistance by the rotary immersion molten steel test.The results showed that SiC,Al_(2)O_(3) and MgAl_(2)O_(4) can improve the sintering properties of BN–ZrO_(2)ceramics;especially,the introduction of SiC can significantly improve the hardness of the material;thus,the above compounds will help to improve the wear resistance of BN–ZrO_(2)ceramics.The exposed oxide layer is in contact with molten steel and forms liquid phase after BN oxidation and B_(2)O_(3) volatilization,additives can significantly affect the properties of liquid phase,and m-ZrO_(2)grains are sintered and grown by dissolution–precipitation mechanism by liquid phase.Consequently,Al_(2)O_(3) and MgAl_(2)O_(4) are more conducive to the formation of working layer with solid skeleton,which determines the corrosion resistance of BN–ZrO_(2)ceramics.展开更多
To improve the properties of low-carbonization of MgO–C refractories,the introduction of composite additives is an effective strategy.Al_(2)O_(3)–SiC composite powder was prepared from clay using electromagnetic ind...To improve the properties of low-carbonization of MgO–C refractories,the introduction of composite additives is an effective strategy.Al_(2)O_(3)–SiC composite powder was prepared from clay using electromagnetic induction heating and carbon embedded methods.Further,the Al_(2)O_(3)–SiC composite powder synthesized by electromagnetic induction heating at 600 A was added into low-carbon MgO–C refractories(4 wt.%)to improve their properties.The results showed that when the addition amount of Al_(2)O_(3)–SiC composite powder is within the range of 2.5–5.0 wt.%,the properties of low-carbon MgO–C samples were significantly improved,e.g.,the apparent porosity of 7.58%–8.04%,the bulk density of 2.98–2.99 g cm-3,the cold compressive strength of 55.72–57.93 MPa,the residual strength after three air quenching at 1100°C of 74.86%–78.04%,and the decarburized layer depth after oxidized at 1400°C for 2 h of 14.03–14.87 mm.Consequently,the idea for the rapid synthesis of Al_(2)O_(3)–SiC composite powder provides an alternative low-carbon MgO–C refractories performance optimization strategy.展开更多
Refractories are considered to be one of the most important materials for the production of iron and steel industry,and some kinds of refractories are often chosen and used;thus,their properties,stability,and longevit...Refractories are considered to be one of the most important materials for the production of iron and steel industry,and some kinds of refractories are often chosen and used;thus,their properties,stability,and longevity play an important role in the improvement in the quality of iron and steel as well as safe production.展开更多
基金supported by Hebei Provincial Natural Science Foundation of China (Grant No.H2022209089)Basic Scientific Research Business Expenses of Colleges and Universities in Hebei Province (Grant No.JYG2022001)+3 种基金Open Fund Project of the Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education (Grant No.FMRUlab23-03)the Basic Scientific Research Business Expenses Research Projects of Colleges and Universities in Hebei Province (Grant No.JQN2023008)the National Natural Science Foundation of China (Grant No.52074128)Hebei Province Innovation Ability Promotion Plan Project (Grant No.23561001D).
文摘Converter slag is a by-product of the steelmaking process and contains a large amount of Ca,Fe,P and other elements.If the phosphorus in the converter slag can be effectively extracted,the resulting phosphorus can be used as a phosphate fertilizer.Phosphorus in converter slag is mainly enriched in 2CaO·SiO_(2)-3CaO·P_(2)O_(5)(C_(2)S-C_(3)P)solid solution and is easily dissolved in water.Therefore,acid leaching method was used to dissolve the solid solution to extract phosphorus in converter slag,so as to realize the recycling of phosphorus resources in converter slag.The leaching behavior of three actual converter slags from different steel mills in acid leaching solutions composed of citric acid,sodium hydroxide,hydrochloric acid and deionized water was studied by X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,Fourier transform infrared spectroscopy and Raman spectroscopy to reveal the change in object image structure as well as SiO_(4) and PO_(4) tetrahedron before and after acid leaching.The results show that only a small amount of phosphorus in converter slag with too low basicity is enriched in C_(2)S-C_(3)P solid solution,resulting in poor leaching effect.When the converter slag has a high basicity,the removal effect of phosphorus is 70.64%-81.88%.In addition,when the basicity of converter slag is roughly the same,the dephosphorization effect of slag with high FeO content is relatively poor.And acid leaching will cause depolymerization behavior of SiO_(4) and PO_(4) tetrahedron,so that the mole fraction of Q0(Si)(asymmetric stretching vibration of Si-O bond in SiO_(4) tetrahedron with bridge oxygen number of 0)and NBO/Si(non-bridging oxygen in silicate tetrahedra)will increase.Phosphate-containing solids can be obtained from the solution after acid leaching through static precipitation,and the solids have the potential to make phosphate fertilizers.
基金the project supported by the Natural Science Foundation of Hubei Province(Grant No.2023BAB106)the National Natural Science Foundation of China(Grant No.U20A20239).
文摘The rapid development of iron and steel metallurgy technology has promoted the continuous innovation and iteration of carbon-containing refractories for clean steel smelting.To meet the high-quality requirements for clean steel production and full exploit the performance advantages of carbon-containing refractories in dynamic smelting environment,it is necessary to explore the role of graphite and modified graphite in carbon-containing refractories.Based on this,graphite surface modification methods,including surfactants,surface oxidation,and surface coating,and their applications in carbon-containing refractories are reviewed.The advantages and disadvantages of each method are analyzed for practical use.Furthermore,combined with the existing problems,the application prospect of improved graphite in carbon-containing refractories is discussed.
文摘This special issue is dedicated to the 3Oth anniversary of Journal of Iron and Steel Research International.In the past 30 years,Journal of Iron and Steel Research International has been focusing on the academic research and advancement in metallurgy and metallic materials.
基金The authors thankfully acknowledge the financial support of the National Natural Science Foundation of China(Nos.U20A20239,U1908227,and 51772236)for sponsoring this work.
文摘The development of low-carbon refractories is of great significance,but it is limited by the deteriorated properties that resulted from the decreased graphite content.Incorporating composite powders has proved to be effective in improving the properties of low-carbon refractories.The recent progress in the synthesis of composite powders including modified graphite,nanocarbon-containing composite powders,oxide/non-oxide and non-oxide composite powders and their applications in low-carbon refractories were reviewed,and the future development of composite powder technology was prospected.
基金The authors acknowledge the financial support from the National Natural Science Foundation of China(U20A20239)Natural Science Foundation of Hubei Province(2020CFB692).
文摘The demand for low-carbon MgO–C refractories is ever growing to meet the development of advanced steelmaking technologies and efficient energy conservation.Meanwhile,to improve the oxidation resistance and inhibit the weakness of low-carbon MgO–C refractories,antioxidants are necessary.The application of ternary carbides that focused on improving the oxidation performance of MgO–C refractories has been explored,and the ternary carbides including Al_(4)O_(4)C,Al8B_(4)C_(7),Al_(4)SiC_(4),Ti_(2)AlC,Ti_(3)AlC_(2),and Ti_(3)SiC_(2)have been proved effective.The crystal structure,physical properties,oxidation behavior,and synthesis of these ternary carbides were summarized,and their oxidation mechanism in assisting antioxidation of MgO–C refractories was discussed.In addition,the potential aspects related to the usage and development of ternary carbides in low-carbon MgO–C refractories were proposed.
基金financially supported by the National Natural Science Foundation of China(U1908227,U1860205,and U21A2057)Key Program of Natural Science Foundation of Hubei Province(2021CFA071)the Special Project of Central Government for Local Science and Technology Development of Hubei Province(20I9ZYYD076).
文摘Al_(2)O_(3)-and MgO-based oxides are among the most common oxides in the steelmaking industry.They exist as the main components of refractories,inclusions,or slags.Al_(2)O_(3)-and MgO-based oxides interact with molten slags continuously during the steel smelting process,which may lead to the dissolution and absorption of the oxides by molten slags,or reactions between oxides and molten slags to form intermediate products.Understanding the dissolution behavior of Al_(2)O_(3)-and MgO-based oxides in molten slags is important for prolonging the service life of refractories and removing inclusions in molten steel.Therefore,Al_(2)O_(3)-and MgO-based oxides are considered,and the test methods,dissolution mechanisms,and influencing factors are comprehensively introduced,which can provide a foundation for refractories wear and high-quality steel smelting.
基金The authors gratefully acknowledge the support of National Natural Science Foundation of China(51932008 and 51772277)Central China Thousand Talents Project(204200510011).
文摘BN–ZrO_(2)ceramics with different additives such as SiC,Al_(2)O_(3) and MgAl_(2)O_(4) were fabricated by hot pressing sintering process to study sintering properties and corrosion resistance by the rotary immersion molten steel test.The results showed that SiC,Al_(2)O_(3) and MgAl_(2)O_(4) can improve the sintering properties of BN–ZrO_(2)ceramics;especially,the introduction of SiC can significantly improve the hardness of the material;thus,the above compounds will help to improve the wear resistance of BN–ZrO_(2)ceramics.The exposed oxide layer is in contact with molten steel and forms liquid phase after BN oxidation and B_(2)O_(3) volatilization,additives can significantly affect the properties of liquid phase,and m-ZrO_(2)grains are sintered and grown by dissolution–precipitation mechanism by liquid phase.Consequently,Al_(2)O_(3) and MgAl_(2)O_(4) are more conducive to the formation of working layer with solid skeleton,which determines the corrosion resistance of BN–ZrO_(2)ceramics.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.U20A20239 and U1908227)the Fundamental Research Funds for the Central Universities(Grant No.N2125002)the open research fund for State Key Laboratory of Advance Refractories(Grant No.SKLAR202001).
文摘To improve the properties of low-carbonization of MgO–C refractories,the introduction of composite additives is an effective strategy.Al_(2)O_(3)–SiC composite powder was prepared from clay using electromagnetic induction heating and carbon embedded methods.Further,the Al_(2)O_(3)–SiC composite powder synthesized by electromagnetic induction heating at 600 A was added into low-carbon MgO–C refractories(4 wt.%)to improve their properties.The results showed that when the addition amount of Al_(2)O_(3)–SiC composite powder is within the range of 2.5–5.0 wt.%,the properties of low-carbon MgO–C samples were significantly improved,e.g.,the apparent porosity of 7.58%–8.04%,the bulk density of 2.98–2.99 g cm-3,the cold compressive strength of 55.72–57.93 MPa,the residual strength after three air quenching at 1100°C of 74.86%–78.04%,and the decarburized layer depth after oxidized at 1400°C for 2 h of 14.03–14.87 mm.Consequently,the idea for the rapid synthesis of Al_(2)O_(3)–SiC composite powder provides an alternative low-carbon MgO–C refractories performance optimization strategy.
文摘Refractories are considered to be one of the most important materials for the production of iron and steel industry,and some kinds of refractories are often chosen and used;thus,their properties,stability,and longevity play an important role in the improvement in the quality of iron and steel as well as safe production.
