1. 清华大学热科学与动力工程教育部重点实验室，北京 100084 2. School of Chemical Engineering, University of Adelaide, South Australia 5005, Australia
Influence of Flame Emission Spectroscopy on K measurement Using Laser Induced Breakdown Spectroscopy
ZHANG Zhi-hao1, SONG Qiang1*, Zeyad T. Alwahabi2, YAO Qiang1
1. Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China 2. School of Chemical Engineering, University of Adelaide, South Australia 5005, Australia
Abstract：During the combustion of coal or biomass, the inherent alkali metals in the fuel will be released to the gas phase. The released alkali species condensed during the cooling of the flue gas, which may subsequently cause problems with ash deposition and corrosion in thermal fuel conversion systems. Laser Induced Breakdown Spectroscopy (LIBS) is an effective technique to measure the alkali species in the plume of burning coal or biomass. In this study, an LIBS experimental system with a flat flame burner was set up, and the Flame Emission Spectroscopy (FES) and LIBS of K in the flat flame environment were measured using different ICCD gate-width times. The experimental results revealed that with the same ICCD gate-width time, the LIBS intensity of K was higher than the FES intensity of K in the flat flame. With the increase of the ICCD gate-width time, both intensities increased, but their increase rates were different: the increase rate of the LIBS intensity of K was firstly fast then became slow, but the increase rate of the FES intensity of K was constant. Furthermore, the intensity ratio of LIBS to FES of K increased monotonically with the ICCD gate-width time in the range of 0～8 μs, until reaching approximately 4. Then, further increasing the ICCD gate-width time, such ratio decreased slowly with an asymptote value of 1. After analyzing the influences of the FES on the LIBS measurement of K in a flame condition, it is proposed that to minimize such influence, the optimization of the ICCD gate-width time was necessary, which maximized the intensity ratio of LIBS to FES of K and facilitated the measurement accuracy of K in the flame environment using LIBS.
张志昊1，宋 蔷1*，Zeyad T. Alwahabi2，姚 强1 . 火焰发射光谱对K元素激光诱导击穿光谱测量的影响 [J]. 光谱学与光谱分析, 2015, 35(04): 1033-1036.
ZHANG Zhi-hao1, SONG Qiang1*, Zeyad T. Alwahabi2, YAO Qiang1 . Influence of Flame Emission Spectroscopy on K measurement Using Laser Induced Breakdown Spectroscopy . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2015, 35(04): 1033-1036.
[1] Baxter L, Miles R, Miles R Jr., et al. Fuel Process. Technol., 1998, 54(1-3): 47. [2] Knudsen J N, Jensen P A, Dam-Johansen K. Energy Fuels, 2004, 18(5): 1385. [3] Li C Z. Fuel, 2007, 86(12-13): 1664. [4] Zhang Z H, Song Q, Yao Q, et al. Energy Fuels, 2012, 26(3): 1892. [5] Hahn D W, Omenetto N. Appl. Spectrosc., 2010, 64(12): 335A. [6] Hahn D W, Omenetto N. Appl. Spectrosc., 2012, 66(4): 347. [7] Cremers D A, Radziemski L J. Laser-Induced Breakdown Spectroscopy (LIBS): Fundamentals and Applications. Cambridge: Cambridge University Press, 2006. [8] SHAO Yan, ZHANG Yan-bo, GAO Xun, et al(邵 妍，张艳波，高 勋，等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2013, 33(10): 2593. [9] Blevins L, Shaddix C, Sickafoose S, et al. Appl. Optics, 2003, 42(30): 6107. [10] Molina A, Walsh P, Shaddix C, et al. Appl. Optics, 2006, 45(18): 4411. [11] He Y, Zhu J, Li B, et al. Energy Fuels, 2013, 27(2): 1123. [12] Hsu L J, Alwahabi Z T, Nathan G J, et al. Appl. Spectrosc., 2011, 65(6): 684. [13] Winefordner J D, McGee W W, Mansfield J M, et al. Anal. Chim. Acta., 1966, 36: 25.
