基于耦合反应机理的转炉冶炼模型

BOF smelting model based on coupling reaction mechanism

转炉内部发生着复杂的多元多相耦合反应,由于静态控制模型只能考虑转炉冶炼过程的始态和末态,无法获知整个冶炼过程中连续的熔池钢水成分和温度变化情况,导致难以对转炉炼钢终点进行精确控制,因此转炉冶炼过程的机理模型搭建对实际生产具有重要的指导意义。在静态模型的基础上基于耦合反应机理建立了转炉冶炼过程模型,并使用C#语言编写了能够用于模型计算的软件。该模型可以计算出冶炼过程中所需造渣剂、冷却剂和耗氧量等,并可以计算熔池温度、熔池成分和熔渣成分随吹炼时间的变化,对钢水终点温度、成分以及熔渣成分进行较为精准地预测。通过改变模型的操作参数,研究了不同供氧强度对脱碳速率的影响和底吹氩气流量对脱磷速率的影响。研究结果表明,供氧强度的变化对脱碳过程前期和中期的影响较为明显,对脱碳过程后期影响较小。底吹氩气流量的增大对脱磷过程前期的影响较大,可以增加脱磷反应的速率,但随着氩气流量的增加,渣中的FeO含量降低,导致脱磷速率降低。通过对比某钢厂转炉100炉实际数据与模型计算结果发现,钢水终点碳质量分数偏差为-0.02%~0.02%的命中率为89%,终点钢水温度偏差为(t±10)℃的命中率为83.0%,实际测量数据和理论计算值在一定范围内的偏差较小,具有指导实践生产的意义。

Complex multivariate and multiphase coupling reactions occur inside the converter.Since the static control model can only consider the beginning and end states of the converter smelting process,it is impossible to know the continuous molten steel composition and temperature changes in the entire smelting process,making it difficult to accurately control the end point of the converter steelmaking.Therefore,the mechanism model of the converter smelting process is of great guiding significance to actual production.Based on the static model,the converter smelting process model is established based on the coupling reaction mechanism,and software that can be used for model calculation is written in C#language.The model can calculate the slag-making agent,coolant,and oxygen consumption required in the smelting process,and can calculate the temperature of the bath,the composition of the bath,and the composition of the slag with the blowing time,and make a more accurate prediction of the temperature,composition,and slag composition of the molten steel end point.By changing the operating parameters of the model,the influence of different oxygen supply intensities on the decarbonization rate and the influence of bottom blown argon air flow on the dephosphorization rate were studied.The results show that the change in oxygen supply intensity has a more obvious impact on the early and mid-stage of the decarbonization process,and it has a smaller impact on the late stage of the decarbonization process.The increase of the bottom blown argon air flow has a greater impact on the early stage of the dephosphorization process,which can increase the rate of the dephosphorization reaction,but with the increase of the argon air flow,the FeO content in the slag decreases,resulting in a decrease in the dephosphorization rate.By comparing the actual data of 100 furnaces of a steel mill converter with the calculation results of the model,it was found that the hit rate of the carbon content of the end point of molten steel in the range of deviation-0.02%-0.02%is 89%,and the hit rate of the end point of molten steel temperature in the range of deviation(t±10)℃is 83.0%.The deviation between the actual measurement data and the theoretical calculated value within a certain range is small,which has the significance of guiding practical production.