点排放源中二氧化碳浓度的测量研究

Investigation on CO_2 Concentration Measurement for Point Emission Source

大气中温室气体浓度的增加引起的全球气候变化是世界关注的焦点问题。在所有的排放源中,固定排放源排放的二氧化碳气体是温室效应的主要因素。政府间气候变化专门委员会(IPCC)将直接测量排放量方法列为温室气体排放清单统计的最高等级,以提高数据统计精度。为了实现排放量的精确测量,固定排放源浓度直接测量至关重要。基于分析吸收光谱建立了相对于纯气体的测量方法,通过多次反射直接吸收光谱技术,建立了精确测量二氧化碳浓度的相对法装置,测量了293 K和0～13 k Pa下二氧化碳在6 362. 5 cm-1的(30012)←(00001) R20e跃迁谱线,通过与纯二氧化碳吸收面积的比较得到15%,35%,50%和75%二氧化碳混合物的浓度。结果表明与天平称重法得到的结果具有很好的一致性,相对扩展测量不确定度在0. 7%以下(k=2)。

The global climate change caused by the increase in the concentration of greenhouse gases( GHG) in the atmosphere is the focus of attention in the world. Among all sources of emissions,the emission of carbon dioxide from point sources is a major factor in the greenhouse effect. The Intergovernmental Panel on Climate Change( IPCC) will directly measure emissions as the highest level of GHG emissions inventory statistics to improve the accuracy of data statistics. In order to achieve accurate measurement of emissions,direct measurement of point source concentration is critical. An off-axis direct absorption spectroscopy technique combined with a long optical path gas absorption cell and a scanning laser frequency method was used to establish a relative method for accurate measurement of carbon dioxide concentration. The absorption spectra of the( 30012) ←( 00001) R20 e transition line at 6362. 5 cm-1 in the range of 293 K and 0 ~ 13 k Pa have been measured. The concentration of 15%,35%,50%,and 75% of carbon dioxide mixture was obtained by comparison with the absorption area of pure carbon dioxide,and a detailed uncertainty analysis was performed on the measurement results. The results have a good consist with the results obtained by the balance weighing method,the expanded relative measurement uncertainty is below 0. 7%( k = 2).