激光诱导击穿光谱技术在燃煤电厂及土壤污染物在线检测中的应用研究

Application of Laser-Induced Breakdown Spectroscopy to Coal-Fired Power Plants and Soil Contaminants On-line Monitoring

介绍了自主研发的激光诱导击穿光谱技术(LIBS)煤质在线检测设备,可完成自动取样并带有自清洁系统,能实时对电厂输煤管道中煤粉的C、Ca、Mg、Ti、Si、H、Al、Fe、S等元素进行自动定量分析并转化为工业分析(发热量和灰分)结果。提出了飞灰含碳量在线检测成套方案并研制了自动采样及LIBS检测装置,建立了去除C线中Fe线的数学方法,利用二阶多元非线性逆回归模型建立了定标方程来校正基底效应,获得了0.26%的C元素测量精度。开发了便携式LIBS设备用于土壤污染物的现场检测,可对土壤中的重金属污染物进行快速的定性分析。

A self-designed laser-induced breakdown spectroscopy（LIBS） equipment with self-cleaning system for on-line coal quality monitoring was introduced.By using the device,automatic sampling can be realized, and automatic real-time quantitative analysis of the elements of C,Ca,Mg,Ti,Si,H,Al,Fe,S in pulverized coal of coal transportation pipeline can be accomplished and be converted into industrial analysis（gross calorific value and coal ash） results.An automated prototype LIBS apparatus has been developed for possible application to power plants for on-line analysis of unburned carbon（UC） content in fly ash.A new mathematical process is proposed to distinguish C line from Fe line,and the second-order polynomial multivariate inverse regression is utilized to establish the calibration model and minimize the matrix effects,with the accuracy of carbon content measurement to be 0.26%.Finally,a portable LIBS device for soil contaminants in situ detection is reviewed,which can accomplish fast qualitative analysis of heavy metal in soil.