钒在FeO-SiO_2-MnO渣系与铁液间的分配行为

在实验室条件下,系统研究了1380℃下,钒在FeO-SiO2-MnO渣系与铁液间的分配行为。结果表明:钒的提取率、钒在渣-金两相的分配比、渣的钒容量随渣中SiO2的质量分数升高而降低。在SiO2的质量分数较低时,以上参数随MnO质量分数的增加而升高。而在SiO2的质量分数较高(>20%)时,随MnO质量分数的增加呈现先升高后降低的趋势。FeO-SiO2-MnO三元渣系中,SiO2的质量分数为10%~20%、MnO的质量分数为13%~5%时,以上参数达到最大值,且该区域对应着FeO-SiO2-MnO渣系熔点最低的区域。V2O3在FeO-SiO2-MnO渣系中活度系数的数量级为10-6~10-7。     

CaO-SiO2-FeOx及CaO-SiO2-P2O5-FeOx渣系热力学性质的研究

CaO-SiO2-FeOx三元渣系和CaO-SiO2-P2O5-FeOx四元渣系是转炉脱磷用渣的主要子渣系,研究这两种渣系的热力学性质可为脱磷渣的高效利用提供理论依据。利于相图软件FactSage分别绘制了这两种渣系的相图,并分析了温度和氧分压对体系相平衡关系和液相线的影响规律。分析结果表明:升高温度会使这两种渣系的液相区扩大,初晶相稳定区域显著减小;降低氧分压会导致尖晶石固溶体相的初晶区消失,磷石英(SiO2)、伪硅灰石(CaSiO3)、α’-Ca2SiO4固溶体相减小。     

转炉渣与镁质耐火材料的润湿机制

 采用静滴法研究了2种情况下转炉渣与炉衬耐火材料的润湿性。当转炉渣与耐火材料直接接触时,转炉渣不熔化,当用刚玉坩埚将两者隔开时,界面处发生反应性润湿,动态接触角随温度升高而单调减小,铺展面积随时间成线性增加。渣中FeO含量由于镁碳砖基板表面的碳及中间产物CO的还原而降低,导致炉渣熔化性温度升高而未熔化。液态熔渣沿镁碳砖表面的气孔和裂纹向基体内扩散、渗透,渣中铁氧化物与镁碳砖机体内的MgO反应生成含高熔点相的黄色渗透层,起到保护炉衬的作用,从而解释了炉渣与耐火材料的粘附机制,为优化溅渣护炉工艺,合理调整炉渣成分和选择耐火材料等工艺操作提供理论依据。     

Phosphorus Capacity of CaO-SiO2-Al2O3-MgO-FexO Slag

The CaO-SiO2-Al2O3-MgO-FexO slag occurs in the production process of Corex ironmaking technology.Most of its metallurgical properties,especially the phosphorus property,are different from the slag produced from blast furnace or converter.In order to explore the dephosphorization ability of CaO-SiO2-Al2O3-MgO-FexO slag,its phosphorus capacity was measured at 1 673 Kby gas-slag-metal equilibrium technique.An iron crucible was used as the reaction vessel,Ag alloy with 0.2% P was used as the metal phase which equilibrated with CaO-SiO2-Al2O3-MgO-FexO slag,and a constant flow of CO-CO2-N2 gas was used to provide oxygen partial pressure in the experiment.The effects of MgO,FexO and basicity on slag phosphorus capacity were investigated by single factor test.The results show that the phosphorus capacity rises firstly and then decreases with increasing MgO content under the condition of basicity 1.3,FexO content of 2% and Al2O3 content of 12%.The phosphorus value reaches maximum as the MgO content is 8%.When the basicity of slag is 1.1,MgO content is 10%,and Al2O3 is 12%,the phosphorus capacity increases with the increase of FexO content.The phosphorus capacity rises linearly when the basicity is increased from 1.1to 1.5.     

Carbon Solubility in the CaO-SiO2-3MgO-CaF2 Slag System

The carbon solubility in the CaO-SiO₂-3MgO-CaF₂ slag system at 1773 K (1500 °C) was investigated under CO/Ar and CO/N₂ gases. Higher extended basicity [(CaO + MgO)/SiO₂) increased the carbon solubility in the slag as the activity of free oxygen ions ( $ \varvec{a}_{{{\mathbf{O}}^{2 - } }} $ ] promoted the reaction of the free carbide mechanism. Higher CaF₂ also resulted in higher carbon dissolution into the slag as fluorine ions interact with the bridged oxygen (O⁰) in the melt structure to increase the activity of the free oxygen ions in the melt. Structural information obtained from the Fourier transformed infra-red (FT-IR) and Raman revealed a depolymerization of the network structure as the simpler structural units of NBO/Si = 4 increased and the Si-O-Si bending vibrations decreased with higher basicity and CaF₂ content. This correlated well with higher free oxygen ions (O^2?) in the slag system and subsequently higher carbon dissolution. A correlation of the theoretical optical basicity (Λ_th) with the logarithm of the carbon content in slag showed a relatively similar trend and an increase of carbon was observed with higher optical basicity.     

Reactions Between Liquid CaO-SiO2 Slags and Graphite Substrates

Metallurgical and Materials Transactions B - In this study, the spreading and infiltration behavior of liquid slag in contact with different grades of graphite was investigated. The wetting and...     

CaO-SiO_2-B_2O_3熔渣的热力学计算模型

根据CaO-SiO2、CaO-B2O3和SiO2-B2O3二元相图确定了熔渣的结构单元,利用熔渣的分子离子共存理论建立了CaO-SiO2-B2O3三元熔渣活度模型。通过对模型求解,可以计算出熔渣中CaO、SiO2、B2O3、CS、C2S、C3B、C2B、CB和CB2的组分活度。分析了熔渣碱度、B2O3含量及温度对熔渣组分活度的影响,其中熔渣碱度的影响最大,B2O3含量的影响次之,温度的影响最小。     

Desulfurization Characteristics of CaO-SiO2-BaO-CaF2-Al2O3-MgO Refining Slag

The desulfurizationcapability,as one of the mosti m-portant indexes of refining slag,has great influence onquality of steel.Desulfurization of molten steel with refi-ning slags has become a focal problemconcerned all overthe world[1-4].However,there weref…     

Molecular Dynamics Simulation of the Structure and Properties of CaO-SiO2-CaF2 Slag Systems

Metallurgical and Materials Transactions B - As a fundamental slag system in metallurgical processes, the CaO-SiO2-CaF2 system, its properties, and related microstructures are of critical...     

Dynamic Wetting of High-Al Steel by CaO-SiO2- and CaO-Al2O3-Based Mold Fluxes

Metallurgical and Materials Transactions B - Wetting of steel by mold fluxes affects the surface quality of steel products. Reaction between [Al] and mold fluxes in the continuous casting of...     

Study on Electronic Conductivity of CaO-SiO2-Al2O3-FeOx Slag System

Inthepast,becauseoflittleknowledgeoftheinfluenceofelectronictransportintheslag,researchworksaboutconductivityoftheslagweremainlyconcentratedonionicconductivity[1—15],so,thedataofelectronicconductivityarefew.Buttheworks[16—19]completedinrecentyearsshowedthatreactionofmetalmeltwithslagiscontrolledbytheconductionofelectronsintheslagundersomeconditions.Theprocessesthatarebeneficialtoelectronimmigratingthroughtheslagbulkandtheslag/metalfilminterfacewilldrasticallyincreasethereactionrateandtheexte…     

CaO-SiO_2-FeO-P_2O_5渣系脱磷影响因素的研究

为了提高转炉渣中CaO的利用率,降低转炉渣的碱度,通过试验研究了CaO粒度、粒状CaO的加入比例、温度和保温时间对含磷富集相的影响。结果表明,适当增大CaO的粒度有利于2CaO·SiO2-3CaO·P2O5固溶体的形成;当渣中粒状CaO的含量较低时,增加粒状CaO的加入比例,可促进渣中大颗粒固溶体的形成并减少渣中磷的含量,但当粒状CaO的含量较高时,2CaO·SiO2-3CaO·P2O5固溶体生成量减少;适当提高温度有利于脱磷反应的进行;随反应时间的延长,2CaO·SiO2-3CaO·P2O5固溶体的粒径增大,而且固溶体中磷的含量也不断增加。     

硫容量模型和在五元渣系CaO SiO2 MgO Al2O3 FetO中的应用

 硫容量和硫平衡分配比是衡量炼钢过程中渣系脱硫能力的重要指标。通过光学碱度模型和KTH模型计算了五元渣系CaO SiO2 MgO Al2O3 FetO的硫容量,并与文献的实验测定值进行了比较。结果表明用KTH模型计算的硫容量比用光学碱度模型计算的硫容量更接近实验值,因此KTH模型可用来预测不同组元渣系的硫容量。还详细研究了硫容量和硫平衡分配比的影响因素,结果表明硫容量随炉渣碱度和温度的增加而增加,硫平衡分配比随着钢液中铝、碳、硅含量的增加而增加。     

Li2O对CaO-SiO2-MgO-Fe2O3-MnO2-P2O5精炼渣系脱磷的影响

在Li2 O替代CaO SiO2 MgO Fe2 O3 MnO2 P2 O5精炼渣系中部分CaO的条件下 ,研究了Li2 O含量、碱度及氧化性对钢液磷含量的影响。结果表明 ,在Li2 O =15 % ,碱度 (CaO +Li2 O) /SiO2 为 2 .0～ 2 .5 ,(Fe2 O3 +MnO2 )为 7%的条件下 ,该渣系对钢液的脱磷率在 70 %以上 ,控制钢液磷含量在 0 .0 0 9%以下。     

Wetting and Erosion of ZrO2-Graphite Refractory by CaO-SiO2 and CaO-Al2O3-Based Mold Slags for Submerged Entry Nozzle

Metallurgical and Materials Transactions B - To moderate the erosion in a slag-line zone and extend the service life of a submerged entry nozzle during continuous casting of high-Mn and high-Al...     

Crystallization Behavior of Liquid CaO-SiO2-FeO-MnO Slag in Relation to Its Reaction with Moisture

Metallurgical and Materials Transactions B - To help maintain the sustainability of the steel industry, we are developing a novel process to recover thermal energy (in the form of hydrogen) and...     

Reaction Mechanism and Kinetics of Boron Removal from Molten Silicon via CaO-SiO2-CaCl2 Slag Treatment and Ammonia Injection

Metallurgical and Materials Transactions B - To improve the boron-removal efficiency of metallurgical-grade silicon by increasing the reaction rate, a combined method with the...     

Effect of B2O3 Addition on Electrical Conductivity and Structural Roles of CaO-SiO2-B2O3 Slag

Metallurgical and Materials Transactions B - The effect of B2O3 addition on electrical conductivity of CaO-SiO2-B2O3 slag was investigated using the four-electrode method. The slag structure was...     

CaO-SiO2-Al2O3-MgO-V2O5渣系中钒还原动力学研究

在实验室条件下,以CaO—SiO2-Al2O3-MgO—V2O5为基渣,进行了碳饱和铁水还原V2O5反应的动力学研究。考察时间、温度、炉渣碱度、炉渣组分、初始V2O5浓度等因素对还原反应速度和还原程度的影响。实验结果表明：渣中V2O5含量随时间逐渐降低,而相应地铁液中V的含量逐渐升高;高温、合适的渣碱度、大的铁渣比以及高的初始V2O5含量,使得还原反应进行较快,效果较好。