转炉炼钢的铁水终点温度是衡量铁水是否符合出钢要求的一个重要指标,目前仍主要依靠人工经验进行控制,其预测精度难以保证。为了能够有效的预测终点铁水的温度,并能满足不同的转炉炉口尺寸的要求,提出了一种基于炉口火焰温度测量的转炉终点铁水温度预测的新方法。利用可以采集可见光和近红外波段的微型光谱仪作为关键器件构建了炉口火焰辐射信息的采集系统,实现对转炉炼钢现场的炉口火焰辐射信息进行实时、有效的采集。同时综合考虑了炉口火焰的实际温度范围和现场的测量距离,通过改进的系统标定方法,对所构建的辐射信息采集系统进行标定,并利用双波长法获得了炉口火焰的辐射温度。鉴于炉口的火焰温度与炉内的铁水温度之间存在着一定的联系,还利用所测得的火焰温度以及与铁水温度相关的转炉吹炼过程参数,建立了基于支持向量机的炉内铁水温度的回归预测模型。对68炉现场采集到的转炉吹炼数据进行验证实验后表明该方法的预测精度要优于人工经验,且接近采用副枪的铁水温度测量方式,可为中小型转炉的终点温度预测提供一种有效可行的方案。
In the basic oxygen steelmaking process,the endpoint temperature of the molten steel is one of the key factors whether the molten steel is qualified for tapping.Currently,it mainly relies on the experienced operators to control the endpoint temperature of the molten steel,and the prediction precision may vary among different operators.In order to realize the effectively endpoint steel temperature prediction of the basic oxygen furnace as well as to meet the requirement of different sizes of the converter mouth,a new method based on the flame temperature measurement at the converter mouth was proposed in this paper.Firstly,a fiber-optic spectrometer system in the visible and near infrared spectral range was designed which can real-timely and effectively realize the collection of the flame radiation information at the converter mouth.Secondly,in consideration of the actual temperature of the flame and the distance between the converter and the designed system,an improved calibration method instead of the halogen lamp was adopted,and the two-color method was employed for the flame temperature measurement.Then a regression model based on the support vector machine was built with the flame temperature and several other parameters of the steel-making process as the input variables of the model.Verification experiment was carried out on 68 industrial data collected in the steelmaking workshop.The results show that the prediction accuracy of this method is superior to the experienced operators,and close to the sub-lance based method.As a result,the proposed method can provide a feasible and effective solution to the endpoint steel temperature prediction for those small-sized and medium-sized converters.