含铌铁水脱硅试验

为从含铌铁水中提铌,降低铁水中硅含量以获得高品质的铌渣,实现铌资源的综合利用。采用100 kW中频感应炉进行底吹氧气冶炼含铌铁水试验,研究含铌铁水在脱硅过程中硅、铌选择性氧化规律。结果表明:铁水温度在1 350℃,造渣剂碱度为1.5,反应结束后铁水中硅、铌的氧化分别为75.8%、21.4%;而温度在1 350℃,造渣剂碱度为4.6,反应后铁水中硅和铌的氧化率分别为:94.0%,5.9%,但高碱度炉渣抑制了锰元素的去除,造成铁水中锰含量较高,降低后续工艺中提铌所得铌渣的品位。在铁水温度为1 350℃,炉渣碱度w(CaO)/w(SiO2)为1.5时,脱硅的限度为0.15%。     

含铌铁水预处理脱硅保铌的研究

 为防止铁水预处理脱硅过程中脱铌,通过中频感应电炉底吹氧气冶炼含铌铁水,研究了铁水预处理吹氧过程中不加渣和加入造渣剂吹炼过程中脱硅保铌的行为及铁水中各元素含量的变化规律。试验结果表明：在铁水温度1623K加入碱度为4的CaO-SiO2-CaF2的造渣剂、供氧强度为0. 5m3/(t·min)时吹氧冶炼,铁水中的硅含量降低到0. 012%(质量分数,下同)时,铌才开始氧化,脱硫率为83%,磷含量不变;在相同的温度和供氧强度,不加造渣剂吹炼时,铁水中的硅降低至0. 16%时,铌开始氧化,硫和磷含量不变;有渣吹炼脱硅保铌终点硅含量是无渣吹炼脱硅保铌终点硅含量的10%,显著脱硫。     

铁水脱硅过程机理的探讨

经脱硅实验与计算表明,脱硅反应的表观活化能不大（４３．９ｋＪ／ｍｏｌ Ｓｉ）,温度对脱硅反应影响。脱硅初期,脱硅受铁水侧传质所控制。ＥＰＭＡ显示了构硅元素在渣铁相本体与渣铁界面存在明显浓度差。所以,一次性投入过多脱硅剂不会增加脱硅速度。加强搅拌有利于提高脱硅效率。     

KR法铁水预脱硅工艺研究

铁水脱硅可减少转炉辅料消耗，是稳定转炉操作、实现少渣冶炼的一项重要工作。本文通过研究烧结矿、球团矿、窑渣等不同脱硅剂的脱硅效果，重点分析铁水温度、初始硅含量、及脱硅渣碱度对脱硅效果的影响，试验结果表明，同样的铁水条件，烧结矿的脱硅效果最佳，脱硅氧利用率超过60%,脱硅率超50%。铁水经过KR预脱硅可稳定转炉入炉铁水成分，同时回收了脱硅剂中的铁资源，并且通过扒渣减少入炉渣量，实现了少渣冶炼，给冶炼生产带来巨大的经济效益。     

碳饱和铁液与CaO-SiO_2-CaF_2-Al_2O_3多元炉渣间钒、硅、锰的平衡和含钒铁水分段脱硅—提钒处理的研究

摘自北京科技大学研究生王新华的博士学位论文,导师:林宗彩教授。 本文对CaO-siO_2-CaF_2-Al_2O_3多元炉渣与碳饱和铁液反应的平衡条件下影响硅钒分离氧化的因素,铁水脱硅保钒处理的反应规律、反应机构,以及脱硅处理后的铁水吹氧提钒处理的反应规律进行了研究。研究表明上述反应平衡条件下,铁水中的钒完全能与硅分离氧化。确定了脱硅处理温度、炉渣组成、反应体系的动力学条件、铁水含硅量、渣碱度等因素对钒的平衡分配比的影响,以及渣中加入CaO、     

碳饱和铁液与CaO-SiO_2-CaF_2-Al_2O_3多元炉渣间钒、硅、锰的平衡和含钒铁水分段脱硅—提钒处理的研究

摘自北京科技大学研究生王新华的博士学位论文,导师:林宗彩教授。 本文对CaO-siO_2-CaF_2-Al_2O_3多元炉渣与碳饱和铁液反应的平衡条件下影响硅钒分离氧化的因素,铁水脱硅保钒处理的反应规律、反应机构,以及脱硅处理后的铁水吹氧提钒处理的反应规律进行了研究。研究表明上述反应平衡条件下,铁水中的钒完全能与硅分离氧化。确定了脱硅处理温度、炉渣组成、反应体系的动力学条件、铁水含硅量、渣碱度等因素对钒的平衡分配比的影响,以及渣中加入CaO、     

铁水炉外喷吹脱硫的工业试验

在5t铁水包中,对高硅铁水喷吹苏打和苏打-石灰混合粉剂进行脱硫试验。结果表明:铁水含硅量为0.5～2.0％,喷吹粉剂量为8～10kg/t,喷吹苏打粉的脱硫率为75.80％,喷吹混合粉剂的脱硫率为68.5～72％。渣中(FeO)和(MnO)含量影响脱硫效果。(FeO)含量增加时,(S)/[S]下降。(MnO)的作用与碱度有关,渣碱度<0.9时,随(MnO)含量增加,(S)/[S]也略增。渣碱度≥1.2时,随(MnO)含量增加,(S)/[S]下降。喷粉后继续吹气搅拌铁水,能进一步降低铁水中的硫含量。     

渣洗法铁水脱硅的工业试验

重庆钢铁股份公司开展了铁水渣洗脱硅的工艺试验,结果表明:采用渣洗法进行铁水脱硅,脱硅率可达52.69%;脱硅剂加入量、铁水原始硅含量及脱硅剂加入速度是铁水脱硅效果的主要因素。讨论了试验中铁水温降、脱硅渣泡沫化的问题。     

KR工序铁水预脱硅工业试验研究

莱钢炼钢厂利用KR脱硫设备进行了铁水预脱硅工业试验,试验确定铁水目标[Si]为0.25%~0.35%。采用新型脱硅剂,脱硅氧效率达70%以上,脱除0.1%[Si]脱硅剂消耗量为9.85 kg/t。影响KR脱硅效率的主要是脱硅渣碱度、铁水温度和加料速度。分析认为,合适的脱硅渣碱度为0.5~0.8,脱硅起始铁水温度为1 350℃,脱硅剂加料速度为3.5~4.5 kg/s。     

不锈钢渣熔融还原中铬在铁浴和熔渣间的分配行为研究

通过正交试验考察不锈钢渣铁浴熔融还原中反应温度、炉渣碱度、渣中Al2O3含量及铁水初始铬含量对铬在铁浴和碱性炉渣间分配行为的影响。试验在石墨坩埚内进行,还原剂为碳饱和铁水中的碳。试验结果表明,对影响渣中铬还原因素的显著性顺序依次为:炉渣碱度>渣中Al2O3含量>铁水初始铬含量>反应温度。此外采用模式识别方法对试验样本进行聚类分析和优化,以获得对渣中氧化铬还原的最佳参数。     

Effect of FeO in the slag and silicon in the metal on the desulfurization of hot metal

Work has been conducted to investigate the effects of FeO in the slag and silicon in the metal on hot metal desulfurization. Laboratory experimental results show that FeO decreases and silicon increases the rate of desulfurization. Silicon in the metal is consumed by the reduction of FeO and also by the desulfurization reaction. A mathematical kinetic model was developed to describe both the effects of silicon and FeO on desulfurization for the laboratory scale. The model predicts the sulfur and silicon content in the metal and the FeO and sulfur content in the slag as a function of time. It is based on four-component simultaneous mass transfer: sulfur and silicon in the metal and FeO and sulfur in the slag. Experimental results, the development of the kinetic model, and a comparison of the model and experimental results are presented.     

SiO2-TiO2-CaO-MgO-FeO-MnO渣系与脱钛过程铁水中Ti-Si平衡热力学模型

 为降低铁水中钛含量,采用烧结矿或球团矿进行铁水包脱钛预处理。基于共存理论,采用Matlab编程软件,建立了铁水包脱钛典型渣系SiO2-TiO2-CaO-MgO-FeO-MnO中TiO2活度计算模型。结果表明,随着MgO、FeO、MnO摩尔分数和炉渣碱度的增大,脱钛渣中TiO2活度下降;随着TiO2摩尔分数的增大,TiO2活度提高。脱钛终点铁水中的钛含量与硅含量呈线性关系,其斜率受温度、铁水成分以及炉渣中SiO2和TiO2活度的影响。计算结果与试验结果及实际生产数据十分吻合。     

Development of a Continuous Desiliconization Process in the Hot Metal Runner of a Blast Furnace

An efficient continuous desiliconization process equipped with a mechanical stirrer in a hot metal runner was newly developed. The facility was installed during the revamping of No.3 blast furnace at Kobe Works, and the commercial operation started up successfully in January 2008. Before the installation of the commercial facility, the reaction behaviour was investigated under various experimental conditions for the application of a mechanical stirring method to continuous desiliconization treatment in the hot metal runner. Hot metal experiments at laboratory scale showed that the stirring intensity was an important factor for the process performance, and the mechanical stirring method was available for the improvement of reaction efficiency. As a result of plant tests, it was confirmed that a higher oxygen efficiency of desiliconization was achieved by the combination of runner arrangement and mechanical stirrer compared with the conventional injection of the desiliconizing agent. According to the reaction analysis of continuous desiliconization in the hot metal runner using the semi‐batch reaction model, it was estimated that the average slag‐metal residence time in the reaction region is improved due to an increased entrainment of foamed slag into the stirred metal bath in the mechanical stirring method, and therefore, it leads to a high desiliconization efficiency. Based on the experimental results, the equipment specifications and the runner design for this process were determined.     

脱硅工艺参数对泡沫渣的影响

用X－光透视装置,观察分析了脱硅工艺参数对泡渣的影响,结果表明,铁水温度过高,过低都会助长泡沫渣,均匀加入适量脱硅剂对缓解泡沫渣是有益的。提高脱硅渣碱度有利于降低泡沫渣,也有利于脱硅。     

转炉铁水预处理脱磷的影响因素

 基于炉外铁水深度预脱硫+转炉铁水预脱磷的铁水预处理工艺是当今低磷或超低磷钢冶炼的重要工艺平台,其中转炉铁水预处理脱磷是关键的技术环节。以国内“双联转炉炼钢法”预脱磷炉实践为出发点,在实验室高温炉上通过顶加脱磷剂、浸入吹氧进行了铁水模拟转炉预脱磷影响因素的试验研究,比较了铁水温度、铁水初始硅质量分数w(Si)_i、脱磷渣碱度、供氧制度、搅拌强度、萤石加入量对脱磷效率的影响。结果表明,各因素对脱磷率影响的顺序为铁水温度＞w(Si)_i＞供氧制度＞脱磷渣碱度、搅拌强度＞萤石加入量;适宜的工艺参数为铁水温度为1 300 ℃,w(Si)_i 为0.10%～0.26%或低于0.30%,脱磷渣碱度为2.9～3.0,供氧制度中气氧与固氧各占50%或固氧稍偏多,维持较高的搅拌强度;转炉内铁水预脱磷处理可不加萤石。     

低硅低温铁水终点磷含量高的原因分析及控制

针对转炉冶炼低硅低温铁水终点磷含量偏高的现象,从冶炼中期炉渣FeO含量、炉渣碱度及倒炉温度等几方面因素对脱磷分配比的影响进行了分析。通过改善化渣条件和成渣途径等相应措施,降低了冶炼终点钢水中的磷含量,提高了钢水的质量。     

The effect of carbon content on the rate of reduction of FeO in slag relevant to iron smelting

In the iron smelting, or bath smelting, process the tapped metal contains high amounts of sulfur and the slag contains high amounts of FeO, relative to blast furnace slag. After tapping, the FeO can be further reduced by carbon in the metal, which will also lead to better desulfurization. Although there have been many studies of the reaction of carbon in iron with FeO in slag, discrepancies exist with regards to the effect of carbon in iron on the rate of FeO reduction in slag, which is the subject of this study. Experiments were conducted at 1723 K, using a slag with basicity close to one with an FeO mass content of 5 %. The rate of reduction was measured using a pressure increase technique. For moderate and high sulfur contents, as in the case of iron smelting, the rate is primarily controlled by the dissociation of CO₂ on the surface of the molten iron. Furthermore, if the effect of carbon on sulfur is taken into account, for the range of carbon mass contents of 2 to 4.5 %, there is no effect of the carbon level on the rate of FeO reduction. At low sulfur contents it was found that there is considerable slag foaming, which inhibits mass transfer of FeO in the slag, and significantly reduces the rate. Even when there is no slag foaming at low sulfur contents, mass transfer of FeO in the slag can influence the rate of FeO reduction.