转炉炼钢的终点控制包括钢水出钢时温度及其成分的控制,炉口火焰能够反映炉内脱碳速率及转炉运行参数等。工业炉燃烧火焰可见光谱段,普遍存在着钾(K)和钠(Na)等碱金属元素的原子发射谱线,利用K的特征谱线相对比值可以计算火焰温度。基于辐射双色法,三色法和谱线相对强度法对转炉口火焰温度进行了测量;数据处理过程中对特征谱线进行了基线拟合提取,小波脊线拟合提取;特征谱线进行了Gauss函数和Lorenz函数拟合。结果表明,辐射测温法对谱线比较敏感,选择合理的波段能够有效,精确地测量火焰温度;采用谱线相对强度法受制于特征谱线的数学模型、谱线的跃迁机率、能级的简并度及火焰的光学厚度,需要分辨率非常高的光谱仪才能进行高温转炉火焰中电子温度的测量。
The end-point control of basic oxygen gurnace (BOF) consists of temperature control and element control. The flame of converter can reflect the decarburization rate and operation parameters of converter. The atomic emission spectra of alkali metals such as kalium and sodium exist in the boiler flames, the temperature of flame can be calculated with the spectral line inversion technique. Two-color method, three-color method and two-line method are used to calculate the flame temperature. The characteristic lines are extracted from the fitting baseline and the wavelet ridge line fitting baseline. Characteristic spectral lines are fitted with Gauss function and Lorenz functiorL The results show that the radiation tbermometry is sensitive to the spectral lines, the reasonable band is necessary to measure the flame temperature effectively and accurately. Two-line method is limited by mathematical model of characteristic spectral line, transition probability of spectral line, degenerate degree of energy level, optical thickness of flame. High resolution spectrometer is necessary to measure the converter flame temperature.