| 摘要: |
| 光腔衰荡光谱法(CRDS)和气相色谱法（GC）均被广泛应用于环境空气中甲烷（CH4）的测定。采用CRDS和GC这2种自动监测方法对CH4标准气体和环境空气样品进行分析比对。结果表明，通过使用统一的标准气体和校准方法，2种方法测定CH4标准气体的不确定度均＜0.5%，CRDS法的不确定度更低；2种方法测定CH4环境空气样品结果的平均相对误差为0.28%，Z检验法显示，2种方法没有显著性差异，并具有很高的相关性和一致性。提出，对于测量精度和稳定性更高的大气CH4监测领域，建议优先选用CRDS法或经过比对达到同等性能的方法；而对于测量精度和稳定性要求稍低的CH4排放源及周边等监测领域，可以采用GC法。 |
| 关键词: 大气 甲烷 自动监测 光腔衰荡光谱法 气相色谱法 比对分析 |
| DOI： |
| 分类号:X832 |
| 基金项目:上海市科研计划基金资助项目（20DZ1204000，19DZ1205000） |
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| Comparison Analysis of 2 Kinds of Continuous CH4 Monitoring Techniques |
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CUI Hu-xiong, DONG Fan, ZHOU Xiao-fenget al1,2,3
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1. Shanghai Environmental Monitoring Center, Shanghai 200235, China;2. Shanghai Besser Environmental Technology Ltd, Shanghai 200233, China;3. Beijing SaakMar Environmental Instrument Ltd. Beijing 102211, China
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| Abstract: |
| Both cavity ring-down spectroscopy (CRDS) and On line gas chromatography (GC) are widely used in the measurement of ambient methane. Comparison tests between CRDS and GC in ambient methane measurement through standard gas and actual gas samples were employed in this paper. The measurement results of ambient air samples showed high correlation and consistency by establishing a unified calibration method with standard gas. The uncertainty for methane standard gases measurement were both less than 0.5%, while CRDS was slightly better. The deviation for methane measurement of them was 0.28% at average, and there are no evident differences by using Z test(α=0.05).In addition, it is suggested that CRDS method should be preferred for the atmospheric CH4 monitoring with higher accuracy and stability, whereas GC method can be used for CH4 monitoring in emission sources and surrounding areas. |
| Key words: Air Methane Online monitoring Gas chromatography Cavity ring down laser spectrometer Comparison |
