摘要
Accurate measurement of trace heavy metal mercury(Hg) in flue gas of coal-fired units is great significance for ecological and environmental protection.Mixed gas was used to simulate the actual flue gas of a power plant in this study.A laser-induced breakdown spectroscopy(LIBS)system for Hg measurement in mixed gas was built to study the effect of mixed gas pressure,Hg concentration in mixed gas and delay time on Hg measurement.The experimental results show that the appropriate low mixed gas pressure can obtain high Hg signal intensity and signal to noise ratio.The Hg signal intensity and signal to noise ratio increased with the increase of Hg concentration in mixed gas.The Hg signal intensity and signal to noise ratio decreased with the increase in delay time.According to the above results,the optimized measurement conditions can be determined.Different Hg concentrations in mixed gas were quantitatively analyzed by the internal standard method and traditional calibration method respectively.The relative error of prediction of the test sample obtained by the internal standard method was within 11.11%.The relative error of prediction of the traditional calibration method was less than 14.54%.This proved that the internal standard method can improve the accuracy of quantitative analysis of Hg concentration in flue gas using LIBS.
作者
Kai RONG
Zhenzhen WANG
Ruomu HU
Renwei LIU
Yoshihiro DEGUCH
Junjie YAN
Jiping LIU
荣凯;王珍珍;胡若木;刘人玮;出口祥啓;严俊杰;刘继平(State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,Xi'an 710049,People’s Republic of China;Graduate School of Technology,Industrial and Social Sciences,Tokushima University,Tokushima 770-8501,Japan;Moe Key Laboratory of Thermo-Fluid Science and Engineering,Xi'an Jiaotong University,Xi'an 710049,People’s Republic of China)
基金
supported by National Natural Science Foundation of China (No. 51506171)。
