底吹氧气-石灰粉炼钢过程喷嘴侵蚀行为特性研究

All over the world, the development orientation of steelmaking technology is to stable the production rhythm，improve the steel quality and reduce the production cost. Based on the current situation of bottom blowing oxygen and powder steelmaking technology, the research object is the nozzle erosion behavior characteristics in the bottom blowing oxygen and lime powder steelmaking process. The research methods will be used, which are mechanism model modeling, numerical simulation, water and heat simulation and hot experiment. The problems in the bottom blowing oxygen and lime powder steelmaking process will be solved, which are the nozzle erosion mechanism with influence factors, the pit morphological characteristic and the parameters to reduce the erosion rate. Finally, experiments will be conducted to verify the research results..On the basis of the research from home and abroad, this project will exploit the applicant’s research results about BOF or EAF steelmaking molten pool flow characteristics and jet metallurgy technology. The experimental conditions are almost ready, which can satisfy the basic requirement of the experiment with a little bit, so this project will be complete successful and smoothly. The research applicants have been engaged for years in steel metallurgy technology, which is no study risk..The acknowledge of the nozzle erosion behavior characteristics will be completed, which will be help for technology improvement, and benefits the safety of bottom blowing oxygen and powder steelmaking technology.

稳定冶炼节奏，提高钢水质量，降低生产成本是国内外炼钢技术发展的主要方向。本项目针对底吹氧气-粉剂炼钢技术的发展现状，以底吹氧气-石灰粉炼钢过程喷嘴侵蚀行为特性为研究对象，通过机理模型建模、数值模拟、水模型等效模拟和热态实验等方法，解决在底吹氧气-石灰粉炼钢过程中，喷嘴侵蚀作用机理和影响因素、喷嘴侵蚀凹坑形貌特征、以及降低喷嘴侵蚀速度冶炼参数设置等问题，并进行实测验证。.在国内外冶金工作者研究基础上，本项目将充分发挥申请人在转炉、电弧炉炼钢熔池流动特性和喷射冶金技术取得的成果优势。课题组实验条件基本具备，稍加完善就能满足本项目的要求，保证了本项目顺利进行。本项目研究方法属于钢铁冶金研究领域的成熟技术，已经过多次实践证明，基本没有研究风险。.通过本项目研究，将完善对喷嘴侵蚀行为特性的认知，为底吹氧气、粉剂炼钢工艺的制定和完善，实现底吹氧气-石灰粉炼钢安全长寿提供理论基础和数据支撑。

底吹氧气-石灰粉转炉可以大幅提高冶金反应效率，降低炼钢的原辅料消耗，获得低磷、低硫、低氧、低氮的纯净钢水，本基金项目针对其炉底寿命短，喷嘴冷却保护、损坏机理和侵蚀变化过程尚不清楚等问题，开展了底吹氧气-石灰粉炼钢过程喷嘴侵蚀行为特性研究。.分别利用数值模拟和水力学模拟的方法，研究了底吹对转炉炉衬冲刷侵蚀的影响，确认了底吹喷嘴附近的侵蚀由回击模型和气蚀模型共同作用，回击模型的侵蚀速率远大于气蚀模型。研究了底吹反应性气体的熔池搅拌特性规律，发现底吹O2或CO2所产生的搅拌功均与转炉脱碳速度相关，在底吹氧气中混入CO2有助于改善吹炼末期的熔池搅拌。.开展高碳镁碳砖在O2-CO2气氛中的脱碳行为研究。发现O2-CO2气氛中的CO2几乎不参与对镁碳砖中石墨的氧化，实验样品的脱碳层深度随CO2混入比例的增加而呈线性关系下降。建立了底吹元件的流-固耦合传热数值模型，研究了O2-CO2混合比例以及底吹喷枪材质结构对底吹元件温度场分布的影响规律，底吹喷枪材质的导热系数对其温度分布有重要影响。研究了不同金属材质和涂层的抗冲蚀磨损性能，发现金属材质都表现出典型塑性材料的冲蚀性能，冲蚀凹坑随着材质硬度的增加而减小，而涂层材质的致密性对其抗冲蚀磨损性能起决定性作用。延长底吹喷枪收缩段的长度，可以有效地抑制粉剂冲蚀磨损。.利用120吨转炉开展了底吹氧气-石灰粉的工业试验，发现底吹喷枪内管的端部侵蚀不均匀，端部呈圆铲状，喷枪内管的烧损速率为1.11~2.20 mm/炉，将底吹喷枪沿轴向剖开，喷枪的主体直管段壁厚均匀，无明显磨损。本基金项目研究结果为底吹氧气-石灰粉转炉的安全长寿运行提供了基础数据和改进新思路，为底喷粉炼钢技术的工程化应用提供了实践经验和理论支撑。