铁碳金属颗粒与熔渣的反应

对ＣａＯ－ＳｉＯ２－Ａｌ２Ｏ３－ＦｅＯ熔渣体系与铁碳金属颗粒反应的脱碳反应速率及脱碳反应限度进行了研究。在实验条件下,脱碳反应速率随金属颗粒初始碳含量及熔渣中氧化亚铁含量的增加而增大。金属颗粒终点碳含量随熔渣中氧化亚铁含量的增加而降低,但反应最终远未达到平衡状态。当反应坩埚内壁衬有金属钼片时,金属颗粒的终点碳含量可以降到极低的水平。因而推断：在低碳含量范围内,熔渣中电子的传递能力对反应起着非常重要的作用     

Heat Transfer in Fluidized Beds in a Dry Slag Granulation Unit

Metallurgist - The world’s leading countries develop dry slag granulation units that are capable of producing solid slag granules and recovering the sensible heat of slag. The main element of...     

高炉渣皮厚度的传热分析

通过有限元软件ANSYS建立高炉冷却壁三维传热模型,利用单元生死技术创立渣皮熔化迭代方法,分析稳态下工艺参数对渣皮厚度的影响.分析结果表明:高炉内炉气温度对渣皮厚度的影响最显著,而冷却水水速影响很小;降低冷却壁气隙宽度可以有效改善高温炉气下的挂渣情况;冷却壁上的渣皮厚度与冷却壁热电偶测定点温度及热负荷之间存在明显的对应关系.采用熔化迭代方法建立的数学模型优化了冷却壁传热分析,能够直接计算不同条件下高炉冷却壁上渣皮厚度.     

粒化钢渣相变传热过程数值模拟

通过建立球形熔渣凝固过程的物理和数学模型,利用现代CFD设计软件FLUENT对不同粒径渣粒的凝固过程进行了数值模拟,得到了凝固过程中渣粒和周围气体的温度场,从而确定了渣粒完全凝固的时间,为熔渣粒化和余热回收设备的设计提供了理论基础。结果表明:渣粒初始温度1 823 K,渣粒直径为1~3 mm,冷却气体温度为373 K,冷却气体流速为1~20 m/s时,液态钢渣相变过程在2 s内释放出80%以上的热量。说明在氮气冷却条件下,只要保证一定的冷却时间,即可保证钢渣余热回收。     

高炉铜冷却壁渣皮生长传热分析

建立了高炉铜冷却壁非稳态传热分析模型,利用ANSYS单元生死技术模拟了冷却壁表面的渣皮再生行为,分析了渣皮脱落后的生长规律及壁体温度和热负荷的变化过程。结果表明,渣皮生长遵循幂函数规律。经过计算,渣皮脱落0.9 min时铜壁测量点温度达到最高值59℃,经过23.5 min趋于稳定。铜冷却壁承受的最高热负荷为107.8 kW/m2,热面最高温度达到123℃。     

转炉冶炼前期溢出渣循环利用技术开发

总结了莱钢股份炼钢厂老区转炉冶炼前期溢出渣循环利用使用经验。开发了转炉冶炼前期溢出渣循环利用技术,通过枪位、渣料、氧压控制,制定了专用操作模型,有效解决了转炉冶炼前期溢出渣循环利用存在的问题,在实际生产中取得了良好的效果,并取得了可观的经济效益,实现含铁固体废弃物短流程直接回炉的综合利用,为中小型转炉经济、清洁生产走循环经济之路探索出新途径。该技术对其他中小转炉厂具有较强的推广意义。     

Melting Characteristics of Recycling Slag in Decarburization Converter and Its Application Effects

 The steel slag in the decarburization converter is treated by the little water-spreading (LWS) and the heat-stewed (HS) methods, which is used as the furnace burden of the dephosphorization converter. The slag characteristics by the LWS and the HS methods and its application effects as the furnace burden are researched. The results show the moisture content in the HS slag is higher than that of the LWS slag. There is higher total iron content in the HS and the LWS slags and almost same melting point. The dicalcium silicate content in the LWS slag is higher than that in the HS slag. The tricalcium silicate in the LWS slag is lower than that in the HS slag. There are a lot of calcium ferrite in the LWS and the HS slags, which is beneficial to dephosphorization and slag melting. The LWS and the HS slags are added to dephosphorization converter each charge by 3 or 6 t. The results show that the saving lime is 0. 7-1. 0 t for each charge. The petrographic constitute of final slag for the dephosphorization converter by adding the LWS and the HS slags is dicalcium silicate, RO phase and glass phase. There are a little calcium ferrite phase in the LWS slag, which is helpful to dephosphorization. So there are better dephosphorization effects for the LWS and HS slags.     

脱磷炉利用脱碳炉返回渣的试验

为了达到节能降耗的目的,脱磷炉采用回吃脱碳炉返回渣的工艺。主要研究了脱碳炉渣的熔化特性以及作为炉料在脱磷炉中的应用效果。结果表明,通过每炉次加入约3.5t的脱碳炉渣,可平均节约1.01t石灰,4.71kg/t钢铁料消耗,脱磷炉终点炉渣的岩相组成主要由硅酸二钙、RO相、玻璃相和少量的金属铁粒组成。加入返回渣后脱磷炉终点炉渣中硅酸二钙和铁酸二钙含量有所增加,玻璃相含量降低,炉渣碱度有所升高,脱磷炉终点钢水成分控制水平有所提高。由此表明,采用脱碳炉渣返回脱磷炉循环利用减少了石灰等原辅料和钢铁料消耗,同时达到了预期的脱磷效果。     

双联脱碳转炉低硅半钢冶炼渣系的优化

 为减少脱碳炉粘枪和降低终点磷含量,运用化学分析、熔点试验、Factsage热力学模拟的方法对120t双联脱碳转炉的渣系进行了研究,阐述了渣系对冶炼顺行的影响,制定了新渣系控制的基本原则和终渣成分范围。工业应用新渣系后,脱碳炉的粘枪状况得到一定缓解,脱碳转炉渣量降低至34.7kg/t,终点磷的质量分数稳定在0006%~0.012%。     

碱度对无氟渣结晶性能、矿相及传热的影响

传统连铸含氟保护渣,不仅污染环境,而且对铸坯和铸机设备也有不良影响。文章采用实验方法模拟结晶器制取渣膜,通过对渣膜结晶性能的研究和矿相组成的测定,得出碱度对无氟保护渣传热的影响规律:在0.9到1.4碱度范围内,碱度主要通过影响渣膜厚度来控制渣膜传热;在1.4到1.7碱度范围内,碱度主要通过影响渣膜结晶率来控制渣膜传热。为解决无氟保护渣准确控制传热问题提供基础信息和理论依据。     

Investigating the Effect of Slag on Decarburization in an AOD Converter Using a Fundamental Model

A high‐temperature thermodynamics model has been coupled with a fundamental mathematical model describing the fluid flow, where boundary conditions were chosen based on data for an industrial AOD converter. Using this model, the effect of both slag phases (a liquid part and a solid part) on the decarburization was studied. More specifically, the separation of chromium oxide to liquid slag as well as the effect of the amount of rigid top slag (solid)on the decarburization was investigated. The liquid slag was considered with respect to the uptake of chromium oxide, while the rigid top slag was only considered with respect to the increase of the metallostatic pressure in the steel melt. The results suggest that separation of chromium oxide to liquid slag results in a decreased decarburization rate. The same conclusion can be drawn with respect to the amount of solid top slag.     

Flow and Heat Transfer Performance of Slag and Matte in the Settler of a Copper Flash Smelting Furnace

Simulation of two‐phase flow in a copper flash smelting settler with simultaneous tapping of slag and matte is carried out using Eulerian‐Eulerian two‐fluid model and the flow and heat transfer performance of slag and matte is examined. Detailed velocity vectors, temperature and volume fraction distributions are obtained. The results show that the small copper droplets will be suspended in the slag. When the droplet diameter is large enough, the slag and matte layer are clearly formed and the dispersion layer between the slag and matte layers becomes thinner at larger droplet sizes and its thickness remains nearly unchanged when the copper droplet diameter is larger than about 500 μm.     

不锈钢传热过程分析及热传导系数的确定

研究了非等温圆柱体热压时的传热规律,并计算出接触表面热传导系数值。在实验室,测定非变形压缩下的1Cr18Ni9Ti不锈钢试样若干点的温度,根据得到的数据分析工件导热特性,利用有限差分技术,确定热传导系数值。     

Effect of Direct Reduced Iron (DRI) on Dephosphorization of Molten Steel by Electric Arc Furnace Slag

Metallurgical and Materials Transactions B - We investigated the effect of direct reduced iron (DRI) addition on dephosphorization of molten steel by electric arc furnace (EAF) slag at...     

Heat Transfer in Steelmaking Ladle

The heat transfer in a steelmaking ladle was studied. The evaluation of heat transfer of the steel was performed by measuring steel temperature in points including all refining steel process. In the ladle, the temperatures in the refractories and the shell were also measured. To evaluate the thermal profile between the hot and cold faces of the ladle in the slag line position, an experiment which shows the importance of thermal contact resistance was carried out. Higher heat losses in the tapping and the vacuum were verified. The temperature measurements of the ladle indicate distinct thermal profiles in each stage of steel refining. Moreover, as each stage of the process depends on the previous one, the complexity of the ladle thermal control is incremental. So a complete model of heat losses in the ladle is complex.