This work presents a study of the applicability of laser-induced breakdown spectroscopy based on infrared transversally excited atmospheric CO₂ pulsed laser for quantitative analysis of main inorganic elements in lignite coals. Calibration standards were prepared by mixing and pelleting an appropriate amount of rock reference material and graphite. Time-integrated spatially resolved measurements of analyte spectra of standard samples were used to construct univariate calibration curves of Al, Si, Ca, Fe and Mg. The spectral intensities of analytical lines were normalized by the carbon spectral line to compensate for the shot-to-shot fluctuation of plasma parameters. The obtained curves of growth have good linearity in a wide range of concentrations (up to 1% for Al and 3% for Si). Correlation coefficients were in the range of 0.955–0.993, depending on the element. Measured limits of detection (from 2.4 to 25 ppm for analyzed metals and 61 ppm for Si) are low enough to control the coal combustion process in power plants. The Stark-broadening and the Boltzmann plot method were used to determine apparent values of excitation temperatures and electron number densities. A relatively small but measurable influence of the concentration of metal elements on the plasma parameters was observed, which should be considered in quantitative analysis of coal samples with higher inorganic elements content.

本工作介绍了基于红外横向激发大气 CO _{2的激光诱导击穿光谱的适用性研究。}脉冲激光定量分析褐煤中的主要无机元素。通过将适量的岩石参考材料和石墨混合并制粒来制备校准标准。标准样品的分析物光谱的时间积分空间分辨测量用于构建 Al、Si、Ca、Fe 和 Mg 的单变量校准曲线。通过碳谱线对分析线的光谱强度进行归一化，以补偿等离子体参数的逐次波动。所获得的生长曲线在很宽的浓度范围内具有良好的线性度（Al 最高为 1%，Si 最高为 3%）。相关系数在 0.955–0.993 的范围内，具体取决于元素。测得的检测限（从 2. 分析金属的 4 到 25 ppm 和 Si 的 61 ppm）足以控制发电厂的燃煤过程。Stark-broadening 和 Boltzmann 绘图方法用于确定激发温度和电子数密度的表观值。观察到金属元素浓度对等离子体参数的影响相对较小但可测量，在对无机元素含量较高的煤样进行定量分析时应考虑到这一点。