90tLF／BD（EMS）真空脱氮工艺研究

介绍了在马钢90tLF／BD（EMS）上进行真空脱氮工艺试验研究的情况,并据此进行了有关真空脱氮的动力学分析,提出了真空脱氮的工艺模型。该模型与试验结果吻合较好。本文还讨论了吹氩搅拌和电磁搅拌对脱氮的影响作用。     

真空感应炉熔炼FN－2合金的脱氮工艺研究

本文就真空感应炉熔炼ＦＮ－２合金的三种工艺的脱氮结果加以比较，并从工艺上进行分析，找出一个可行的最佳工艺，认为在精练期充分点式和增加工频电磁搅拌能明显提高脱氮水平．     

钢液VD真空处理脱氮数学模型

根据钢液VD真空处理过程氮溶解热力学和脱氮动力学理论,建立了高碳钢VD真空处理过程脱氮的数学模型。采用该模型结合VD处理过程的工艺条件,可实现钢液VD真空处理过程脱氮预测。     

真空感应炉熔炼FN—2合金的脱氮工艺研究

本文就真空感应炉熔炼ＦＮ－２合金的三种工艺的脱氮结果加以比较，并从工艺上进行分析，找出一个可行的最佳工艺，认类精炼期充分脱氧和增加工频电磁搅拌能明显提高脱氮水平。     

真空感应炉熔炼FN—2合金的脱氮工艺研究

本文就真空感应炉熔炼ＦＮ－２合金的三种工区怕脱氮结果加以比较，并从工艺上进行分析，找出一个可行的最佳工艺，认为在精炼期充分脱氧和增加工频电磁搅拌能明显提高脱氮水平。     

金属液的脱氮

本文综述了金属液熔渣脱氮、真空脱氮和气泡携带法脱氮方法。熔渣脱氮热力学研究主要涉及脱氮反应和熔渣的氮容量。真空度、氩气搅拌和金属液中氧、硫浓度是影响真空脱氮和气泡携地脱氮的主要因素。     

真空感应炉提纯铁的脱氮问题

本文就Ａ、Ｂ两种方案的真空感应炉提纯铁的不同脱氮效果进行了讨论，认为过多的氧化剂极大地影响脱氮，增加工频电磁搅拌和延长精炼期时间对脱氮有利。     

RH精炼工艺脱氮的影响因素

通过对马钢120t RH精炼炉进行脱氮工艺试验,分析了钢水脱氮率与初始氮含量、真空度、循环次数以及渣层厚度之间的关系。试验结果表明,RH真空下的脱氮率受诸多工艺因素的相互共同制约,初始氮含量对脱氮率的影响呈现阶梯性的特点,低真空度是获得较高脱氮率的必要条件,循环次数保持在10~12次范围内,脱氮效果最佳。渣层厚度对脱氮有双重影响,应合理控制渣量,使RH渣层厚度避开130~150mm区间。     

真空下钢液脱氮工艺研究

在４０ｋｇ真空感应炉上进行了真空下钢液脱氮工艺的实验研究。实验考察了真空下碳氧反应工艺、表面活性元素控制和脱氮渣系等因素对钢液脱氮动力学的影响。研究结果表明：（１）真空下强烈的碳氧反应能有效地脱除钢中的氮;（２）当钢中硫含量较低时,脱氮速率很快,随着硫含量的逐步增加,脱氮速率相应降低;（３）５０％ＳｉＯ２－４０％Ｂ２Ｏ３－１０％ＴｉＯ２渣系有明显的脱氮效果。     

100 t真空罐式精炼炉脱氮工艺实践

概述了真空脱氮的热力学和动力学,分析了影响真空脱氮的因素,介绍了安钢100tVD脱氮的工艺实践及其效果。     

LF/VD过程钢液氮含量控制试验研究

结合现场试验分析了LF/VD过程影响钢液氮含量的因素。结果表明:低氧、低硫钢液,在LF精炼钢液容易吸氮,而在VD有利于脱氮;LF过程喂线可使钢液增氮;真空度小于53.3Pa,保持时间大于10min,可生产出w(N)低于40×10~(-6)的钢液。     

Source and Control of Nitrogen for X70 Pipeline Steel

The effects of some key factors on nitrogen absorption during the smelting process of X70 pipeline steel were studied,and the source of nitrogen pick-up was analyzed to find the bottleneck for nitrogen control.A series of measures were put forward to decrease the nitrogen pick-up.The results indicated that an exponential relationship existed between the nitrogen absorption index and the free oxygen in molten steel.Nitrogen absorption index could decrease below 0.3when free oxygen in molten steel was above 100×10~(-6) after tapping.For low sulfur killed steel,the nitrogen absorption ratio and sulfur content satisfied a linear relationship with a slope of-0.007.Low free-oxygen and sulfur were beneficial to the deep desulfurization during vacuum treatment.The contradiction of high desulfurization ratio and low nitrogen pick-up during LF process could be resolved by skimming oxidizing slag after tapping and making new high basicity top slag.After optimization,the average content of nitrogen in final product decreased from 46×10(-6)to 35×10(-6).     

RH精炼过程增氮行为探讨

为了在RH精炼过程对氮的质量分数进行稳定控制,通过热力学计算分析钢水成分、RH真空度等对理论平衡氮质量分数的影响,分析RH提升气体从吹入上升管到进入真空室过程中压力的变化对平衡氮质量分数的影响。从动力学角度分析气相中的传质阻力、界面化学反应阻力、液相中的传质阻力共同作用于钢液的增氮、脱氮过程。提出RH处理过程的3种增氮途径及其对应的平衡氮质量分数。当钢种要求氮质量分数大于真空度下的理论平衡氮质量分数时,RH处理过程存在增氮、脱氮共存的状态。在氮质量分数变化过程中,当脱氮速度等于增氮速度时,钢液中氮质量分数达到动态平衡,不再发生变化。在真空度为5 kPa的条件下,RH钢液中氮质量分数达到动态平衡,不再发生变化时对应的氮质量分数为0.010 0%。     

Behaviors of Denitrogenation in RH-MFB

 According to the analysis related to kinetic mechanism of vacuum denitrogenation and combining with the actual production of RH-MFB (a combination of Ruhstahl-Hausen vacuum degassing process with a multifunctional oxygen lance) at Liansteel, the limit step and model equation of vacuum denitrogenation are determined. Meanwhile, the influencing factors of nitrogen removal from liquid steel in vacuum of RH-MFB are analyzed. The results show that the limit step of vacuum denitrogenation in RH-MFB is the mass transfer of nitrogen in liquid boundary layer and the reaction follows first order kinetics. Keeping the necessary circulation time under the working pressure (67 Pa) is helpful to nitrogen removal from steel. The oxygen content in molten steel has little influence on the removal of nitrogen after deep deoxidation, while the sulphur content in liquid steel is always relatively low and has little effect on denitrogenation. The sharp decrease of carbon content in steel drives the process of denitrogenation reaction so as to exhibit a faster denitrogenation rate. The interfacial chemical reaction and argon blowing play a major role in the nitrogen removal when the carbon content in liquid steel is stable.     

Cr12N高氮钢冶炼过程中氮的控制

在高温高压反应釜内冶炼Cr12N高氮钢,通过试验发现,在Cr12N的熔炼过程中,随着压力的提高,钢中的氮含量不断增加,钢锭中得到的固相中氮的饱和溶解度和Chipman等人的热力学模型计算得到的氮的饱和溶解度有一定的偏差,为了修正这个偏差,引进了Burton-Prim-Slichter方程,修正后得到液相中氮的饱和溶解度的修正值和计算值吻合得很好。计算了在Cr12N的冶炼过程中,防止气泡析出所需要的最小凝固压力为2.84 MPa,通过试验发现,在高的凝固压力下,钢锭的致密性和缩孔现象得到明显改善。     

VD 真空吹氩脱氮模型

对Gaye真空吹氩脱氮模型进行了修正,并利用修正后的模型研究了真空度,吹氩量以及氧,硫含量等因素对VD真空吹氩脱氮效果的影响,结果表明,模型计算值与实测值符合较好,证明修正后的模型能够较好地模拟VD真空吹氩脱氮过程。     

钢液真空脱氮动力学研究

研究了真空度对钢液脱氮动力学的影响。结果表明,真空度为６７Ｐａ及１１０Ｐａ进,脱氮的限制性环节为氮在钢液液相边界层中的传质,真空度为２０００Ｐａ时,脱氮的限制性环节为氮在气液界面的化学反应。真空下的碳氧反应对脱氧效果有明显的影响,当有碳氧反应时,钢液脱氮速度常数增大,同时钢液内生或外来固态粒会作为气泡形核核心,加速脱氮过程。     

衡管40tVD精炼工艺实践

总结了衡阳钢管厂40tVD的精炼生产实践和精炼效果,从理论上分析了真空处理时间、氩气搅拌流量、钢中氧和硫的含量等对真空脱气、脱氮的影响.同时分析了真空精炼对钢液脱氧及夹杂物控制的影响.结果表明,衡管40tVD炉精炼具有良好的冶金效果.     

100t VD精炼脱气工艺实践

总结了安阳钢铁集团有限责任公司第一炼轧厂100tVD装置在热调试和试生产期间的精炼工艺实践及精炼效果,分析了真空处理时间、氩气搅拌流量、渣量、钢中硫和氧含量等对真空脱氢、脱氮的影响。同时分析了真空精炼对钢液脱氧及夹杂物控制的影响。     

Combined decrease of sulphur,nitrogen, hydrogen and total oxygen in only one secondary steelmaking operation

The development of a matured metallurgical process allows the reduction of the sulphur, nitrogen, hydrogen and total oxygen content to the lowest values in only one secondary metallurgical step during treatment in a ladle tank degassing unit. By careful adjustment of a lime-saturated ladle top slag at the beginning of the vacuum treatment, it is possible to obtain a desulphurization degree of more than 95%. The process of nitrogen removal by a stirring gas can be described with a dynamic model in excellent agreement with plant trials. The nitrogen content after vacuum treatment depends mainly on the nitrogen content before vacuum, the stirring gas quantity and the sulphur content. The achievable hydrogen contents mainly depend on the stirring gas quantity and dehydrogenisation can be described by the same model used for denitrogenisation. By a cleanliness stirring after the vacuum treatment under a nearly SiO₂-free-, lime-alumina slag, saturated with lime, the total-oxygen content can be lowered to less than 20 ppm.