调质剂对 LATS 精炼渣熔点与脱硫能力的影响

为减少LATS-OB精炼浸渍罩粘渣及提高浸渍罩寿命,分别用CaO-CaF₂、CaO-B₂O₃及Li₂O作为钢包渣的调质剂进行调质实验。熔渣半球点法的熔点测试结果表明,采用CaO／CaF₂=1或2,CaO／B₂O₃=1或2和Li₂O作调质剂能显著降低钢包渣的熔点;渣-金平衡试验表明,调质后的钢包渣可使钢中的硫含量进一步降低。     

CaO B2O3对钢包精炼渣的调质处理

 为减少钢包合金化精炼浸渍罩粘渣,以质量比1∶1配制的CaO B2O3作调质剂对钢包顶渣调质,研究调质剂对渣熔化温度、粘度及脱硫能力的影响。半球法熔化温度测定结果表明,调质剂的助熔效果明显,当其加入量为10%时,渣熔化温度从调质前的1 439 ℃降至1 320 ℃。旋转柱体法粘度测试结果表明,调质剂能有效降低精炼处理后钢包顶渣的粘度。在1 500 ℃时,未调质的钢包顶渣粘度约为65 Pa·s,调质后渣的粘度低于20 Pa·s。调质处理后的钢包渣不会引起钢液的回硫,并可使钢中硫含量进一步降低。     

Li_2O对钢包精炼渣的调质处理

为减少钢包合金化精炼浸渍罩粘渣,以Li2O作调质剂对钢包顶渣调质处理,研究Li2O对钢包顶渣的熔化温度、黏度及脱硫能力的影响。半球法熔化温度测定结果表明:Li2O的助熔效果明显,当其加入量为5%时,渣熔化温度从调质前的1439℃降至1300℃;旋转柱体法黏度测试结果表明:钢包顶渣的黏度高以及合金化精炼处理后顶渣黏度进一步升高,是造成浸渍罩粘渣的主要原因,Li2O能有效降低精炼处理后钢包顶渣的黏度,在1500℃时,未调质的钢包顶渣黏度约为6.5 Pa.s,调质后渣的黏度低于2 Pa.s。调质处理后的钢包渣不会引起钢液的回硫,并可使钢中硫的含量进一步降低。     

钢包铸余渣作为转炉脱磷助熔剂理论及实践

针对铝酸钙系精炼钢包铸余渣代替萤石作为转炉助熔剂对脱磷效率的影响,首先利用Factsage热力学软件对比计算分析了Al2O3、CaF2作为转炉炉渣助熔剂,对脱磷产物活度及磷容量的影响规律,并在实验室硅钼炉上对脱磷效率影响规律进行了对比研究。在此基础上,研究了精炼钢包铸余渣代替萤石的替代比例及应用效果。结果表明,分别以Al2O3、CaF2作为转炉脱磷助熔剂时,二者对炉渣碱度的控制要求相当;CaF2的助熔能力明显强于Al2O3,而Al2O3能降低脱磷产物的活度,增加炉渣磷容量,相比CaF2对脱磷反应具有热力学优势;w((Al2O3))为5.0%～9.0%的炉渣达到的脱磷效率,与w((CaF2))为3.0%～6.0%时相当;用武钢铝酸钙系钢包精炼铸余渣代替萤石作为转炉炼钢脱磷助熔剂,其与萤石的替换比例为2.5∶1,冶炼过程炉渣熔化良好,转炉终点钢水脱磷率提高3.0%左右。     

环保型高磷铁水预脱磷渣的脱磷性能研究

实验室条件下采用间接测量法,测定了CaF2系和B2O3系脱磷渣的磷分配.即首先测量磷在液态渣和固态铁间的分配比,再通过计算得到磷在液态渣和铁水之间分配比,同时根据渣系成分和光学碱度计算了磷容量.同时采用了扫描电镜、能谱分析与X射线衍射分析技术对脱磷渣进行了研究.实验结果表明,B2O3系预脱磷渣的磷容量远大于CaF2系预脱磷渣的磷容量,因此可以用B2O3全部替代CaF2作为助熔剂进行高磷铁水的预脱磷处理,2种渣系的磷分配均随渣中有效CaO含量的升高而升高.用B2O3作为助熔剂时,B2O3能与渣中高熔点物质2CaO·SiO2和3CaO·P2O5反应生成低熔点物质,从而起到助熔的作用.且w(B2O3)/w(CaO)比值为0.16时,磷分配比为最高值,即该渣脱磷能力最强.     

B2O3在CaO-BaO-SiO2-Al2O3-CaF2精炼渣中的作用

选择w（CaO）=46％，w（BaO）=10％，w（SiO2）=11．2％，w（Al2O3）=11．6％的渣作基础渣系，将B2q作助熔剂替代CaF2，发现B2q和CaF2的助熔效果相当，B2q可用作环保型助熔剂。将CaO-SiO2-BaO-Al2O3-CaF2作基础渣系，B2O3作酸性氧化物，在碱度（m（CaO＋BaO）／m（SiO2＋B2O3））为2．5和2．8时，研究B2O3替代SiO2后精炼渣的熔化性能。结果表明，B2O3替代25％的SiO2后就可大幅度降低粘度，并且发现富硼精炼渣的高温熔化性能稳定，粘度值稳定在0．3～0．5Pa·s。在碱度为2．8wt进行脱硫工艺实验，当w（SiO2）=20．6％时渣剂脱硫率为80％，当w（SiO2）=10．3％，w（B2O3）=10．3％时渣剂脱硫率为91．3％，主要原因是熔化性能良好的熔渣有助于提高传质速率。     

LF脱硫精炼渣的发展

在对传统精炼渣的局限性进行探讨的基础上,论述了BaO、B2O3代替精炼渣中的CaO、CaF2对熔化特性和脱硫性能的影响,展望了这些替代剂的发展前景。结果表明：BaO不仅具有较好的脱硫能力,还可以降低精炼渣的熔点,提高熔渣流动性,BaO的最佳质量分数为5%~25%。B2O3在渣中的质量分数在10%以内时,可以代替CaF2,起到降低侵蚀炉衬和污染环境的作用。     

Effect of B_2O_3 on Melting Temperature of CaO-Based Ladle Refining Slag

B2O3 is selected as fluxing agent of CaO-based ladle refining slag to decrease the melting temperature as well as to improve the speed of slag forming and the refining efficiency.The effects of B2O3 on the melting temperature of two series of refining slags including the low basicity slags(the mass ratio of CaO/SiO2 is 3-4)and the high basicity slags(the mass ratio of CaO/SiO2 is 5-8.75)were investigated.The slag melting temperature was measured using the hemisphere method.The results indicate that the fluxing action of B2O3 is better than that of CaF2 and Al2O3.For the CaO-based refining slag with low basicity,the melting temperature is decreased effectively when B2O3 is used to substitute for equal mass of CaF2,Al2O3 and SiO2,respectively.For the CaO-based refining slag with high basicity,when CaF2 is substituted by B2O3,the melting temperature can be decreased remarkably.Especially,when the mass ratios of CaO/Al2O3 and CaO/SiO2 are in the range of 1.1-4.0 and 5.25-8.0,respectively,the slag melting temperature is lower than 1300 ℃.Therefore,the B2O3-containing refining slags with high ratios of CaO/Al2O3 and CaO/SiO2 have ultra low melting temperature.     

Li2O、Na2O、K2O、BaO对CaO基钢包渣系性能影响的实验研究

为改善钢包渣性能以控制钢包中钢液回磷,以Li2O、Na2O、K2O、BaO作添加剂替代模拟的CaO基钢包渣系中等质量的CaO，研究添加剂对渣系的熔点、粘度和脱磷能力的影响，并推荐Li2O作为CaO基钢包 渣系的添加剂。     

CaF2-SiO2-Al2O3-CaO-MgO五元渣系的电导率

 为了系统研究五元含氟渣系各组元对熔渣电导率的影响,根据5因素2次正交旋转回归法设计渣系,使用RTW-10熔渣物性测定仪,采用交流4探针法,测定了1600℃下各渣系的电导率;研究了各组元对含氟渣系电导率的影响。结果表明：当CaF2的含量(质量分数,下同)在10%~75%时,随着Al2O3和SiO2含量的增加电导率逐渐减小,而随着CaF2、MgO和CaO含量的增加电导率逐渐增大;在w(Al2O3)=20%、w(MgO)=10%和w(CaF2)=50%时,当w(CaO)小于7%,随着w(SiO2)的递增电导率逐渐减小,而当w(CaO)大于7%时,随着w(SiO2)的递增电导率逐渐增大;在w(SiO2)=10%、w(MgO)=10%和w(CaF2)=50%时,当w(Al2O3)小于11%时,随着w(CaO)的递增电导率逐渐减小,当w(Al2O3)大于11%,随着w(CaO)的递增电导率逐渐增大。     

LF脱硫精炼渣的发展

在对传统精炼渣的局限性进行探讨的基础上,论述了BaO、B2O3代替精炼渣中的CaO、CaF2对熔化特性和脱硫性能的影响,展望了这些替代剂的发展前景。结果表明：BaO不仅可以降低精炼渣的熔点,提高熔渣流动性,还具有较好的脱硫能力,BaO的最佳质量分数为5%~25%;B2O3在渣中的质量分数在10%以内时,可以代替CaF2,起到降低对炉衬侵蚀和对环境污染的作用。     

CaF2对铝酸钙预熔精炼渣系预熔特性和脱硫的影响

在实验室条件下，配制了以CaO Al2O3系为基添加少量氧化镁、二氧化硅构成的四元渣系。研究该渣系中添加不同比例氟化钙预熔后所得渣系的性质。结果表明，添加氟化钙后得到的预熔渣脱硫效果较同组不加氟化钙的差，故采用不添加氟化钙预熔后得到以12CaO·7Al2O3为主的铝酸钙预熔渣系。该渣系具有熔点低、光学碱度高、脱硫能力较强的特点，脱硫率达到80%。     

Mechanism of Slag Composition Change During Electroslag Remelting Process

 The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for the design and analysis of the experiment. The experimental results indicated that mass loss rate of slag can be increased by 6% with CaF2 changing from 50% to 65%. Mass loss increases with SiO2, Al2O3 and MgO adding and decreases with CaO content increasing. Because of the reaction between oxide and fluoride in the slag pool, apparent mass loss of CaF2-Al2O3-CaO-SiO2-MgO slag system appears at melting point. This will cause obvious composition change of electroslag. In addition, the segregation occurs in the slag skin forming process. This is another reason causing the composition change of electroslag.     

Effects of B2O3 and CaF2 on Melting Temperatures of CaO-SiO2-Fe2O3 System Fluxes

 Fluorite is widely employed as fluxing agent in metallurgy flux, which inevitably leads to serious fluorine pollution. B2O3 is employed as fluxing agent of CaO-SiO2-Fe2O3 steelmaking fluxes to substitute for CaF2. The effects of B2O3 and CaF2 on the melting properties of this system were investigated. The melting temperatures of fluxes including softening temperature (Ts), hemispherical temperature (Th), and flow temperature (Tf) were measured using the hemisphere method. The results indicate that the fluxing effect of B2O3 is more significant than that of CaF2. When the addition amount of B2O3 (mass percent) exceeds 6%, the melting temperatures of fluxes including Ts, Th and Tf are decreased lower than 1300 ℃. The basicity of fluxes has a significant effect on the melting temperature, and the melting temperatures of the fluxes increase with the increase of fluxes basicity. However, when B2O3 is used as fluxing agent, the melting temperature changes little with the basicity increasing from 2. 5 to 5. 0. These characteristics are suitable for steelmaking process. Moreover, Fe2O3 has an important fluxing effect on this CaO-based steelmaking fluxes. This indicates that the fluxes system is suitable for steelmaking process.     

高铝炉渣熔化性温度的研究

由于矿石资源的变化,武钢高炉炉渣中Al2O3含量从原来的14%左右上升到16%左右,渣型结构发生了很大的变化。通过对高炉高Al2O3炉渣熔化性温度的试验研究,分析了炉渣中MgO含量、Al2O3含量及二元碱度RO对炉渣熔化性温度的影响以及配加CaF2后熔化性温度的变化。结果表明:Al2O3含量每增加1%时,炉渣熔化性温度平均提高4.4℃;MgO含量对熔化性温度的影响不大;二元碱度RO每增加0.05时,炉渣熔化性温度平均提高8℃;在炉渣中配加了CaF2后,Al2O3含量的变化对炉渣的熔化性温度影响较小。     

LF精炼渣发泡性能的预测模型

对CaO-Al2-SiO2-MgO-CaF2系钢包炉精炼渣泡沫化的影响因素进行了因次分析，根据理论分析的结果和实验数据得到了无氟化钙和低氟化钙炉渣泡沫化指数与炉渣成分之间的关系式。     

电渣重熔用五元高氟渣高温挥发机制

 为探究高温过程电渣组元挥发机理，以电渣重熔用高氟渣CaF2 CaO SiO2 Al2O3 MgO五元渣系为基础研究炉渣高温挥发机制，通过FactSage理论计算、热重及高温质谱检测，结合1 000～1 500 ℃高温焙烧试验以及XRF检测与SEM物相观察，对炉渣加热过程成分及物相变化进行了研究。结果表明,温度为550～800 ℃时，CaF2与SiO2反应生成SiF4气体；温度为800～1 200 ℃时，CaF2与MgO反应生成MgF2气体，同时与少量Al2O3反应生成AlF3气体；温度为1 200～1 500 ℃时，挥发分主要为CaF2及少量AlF3。在高温区(1 000～1 400 ℃)，晶体主要为二铝酸钙和和少量枪晶石；当温度达到1 500 ℃，晶体主要为枪晶石结构，为探究高温过程电渣组元挥发机理以及电渣制备工艺的优化提供参考。     

高钛型高炉渣中B2O3替代CaF2的作用机理

 为了提高含钛炉渣的流动性能以及促进渣铁更有效地分离，并替代对环境污染较大的CaF2资源，运用扫描电镜、黏度仪等设备在1 340～1 475 ℃温度范围内研究了B2O3及CaF2对含钛炉渣表观黏度的影响规律。结果表明，B2O3具有和CaF2相似的作用效果，均能够降低含钛炉渣的表观黏度。当B2O3及CaF2的添加量为1%时，B2O3与CaF2的替代比为1[∶]1；随着渣中B2O3添加量从0增加到3%，钙钛矿质量分数逐渐降低，富钛深绿辉石随之增加，而Ti（C，N）质量分数几乎不变。     

赤泥预还原球团的熔分

为了实现赤泥资源高附加值化综合利用,通过高温模拟试验对赤泥含碳球团还原焙烧-熔分过程进行研究。将赤泥含碳球团在1 200℃下进行还原焙烧,并结合相图分析,向粉碎后的焙烧球团中添加一定比例的CaO、Al_2O_3进行调质和熔分。结果表明,赤泥含碳球团在1 200℃下还原12min后金属化率可达91.3%,还原效果良好;在1 450℃下进行还原熔分,可实现渣铁的有效分离,金属铁收得率可达到90%以上,所得铁水质量符合炼钢要求;熔分渣中w(TFe)可降至0.5%以下,渣中主要物相为12CaO·7Al_2O_3、CaTiO_3和2CaO·Al_2O_3·SiO_2,通过熔点性能测试试验,熔化性能符合钢液脱硫条件。     

Performance of Low Fluoride Dephosphorization Slag of Hot Metal

 The purpose of this study is decreasing content of CaF2 in dephosphorization slag. The dephosphorization effects with CaF2 replaced by B2O3 were investigated. The dephosphorization experiments were carried at 1450℃ in air atmosphere. The results show that the melting points and dephosphorization ratios change little when B2O3 replaced CaF2. The dephosphorization ratios which are all greater than 80% and melting points can meet the requirement of hot metal pretreatment. Because of the change of alkalinity caused by B2O3, the oxidation of slag increases with increasing of B2O3 contents. It is beneficial to pre-dephosphorization. As a result, for decreasing its pollution, CaF2 can be replaced by B2O3 to dispose fluoride-free pre-dephosphorization slag.