一种用于测定天然气发热量的声光关联法

目的 介绍一种利用声速和可见光光谱关联测定天然气发热量的方法，以便国内天然气质量检测和能量计量工作者与企业能更有效地开展该方法的研究和标准化，同时也为天然气发热量测定方法提供更多样性的选择。方法 在对比分析各种天然气发热量测定方法和相关标准优缺点的基础上，介绍了利用声速和可见光光谱关联测定天然气发热量的方法原理，并分析了一组气体标准物质采用气相色谱法和介绍的关联法测定获得的发热量数据。结果 利用声速和可见光光谱关联测定的天然气发热量测定值与按GB/T 11062-2020《天然气发热量、密度、相对密度和沃泊指数的计算方法》的计算值一致性较好，对6种模拟天然气的二元气体标准物质，相对偏差在0.03%～0.42%之间；对5种模拟天然气的多元(最多14个组分)气体标准物质，相对偏差在-0.45%～0.38%之间。结论 初步验证了利用声速和可见光光谱关联法测定天然气发热量的可行性。该方法具有1 s内可获得多个数据、与流量测量同步、测量不受气体组分的限制和H₂影响的特点和优势。建议进一步开展准确度、测定范围、精密度以及现场应用的研究，并适时建立标准方法、发热量直接燃烧0级测...

A sound-light spectrum correlation method for cletermining the calorific value of natural gas

ObjectiveThis paper introduces a method for determining the calorific value of natural gas by using the correlation of sound velocity and visible light spectrum, so that domestic natural gas quality detection and energy measurement workers and enterprises can more effectively carry out the research and standardization of this method, and provide more diversified choices for the determination methods of calorific value of natural gas. Methods Based on the comparative analysis of the advantages and disadvantages of various natural gas calorific value determination methods and related standards, the method principle of using sound velocity and visible light spectrum correlation to determine the calorific value of natural gas is introduced, and the calorific value data of a group of gas reference materials determined by gas chromatography and the introduced correlation method are analyzed. ResultsThe measured value of calorific value of natural gas determined by the correlation between sound velocity and visible light spectrum is in good agreement with the calculated value according to GB/T 11062-2020 Natural gas-Calculation of calorific values, density, relative density and Wobbe indices from composition. For six binary gas reference materials simulating natural gas, the relative deviation is between 0.08%-0.42%; For five kinds of multi-component (up to 14 components) gas reference materials simulating natural gas, the relative deviation is -0.45%-0.07%. ConclusionsThe feasibility of measuring the calorific value of natural gas by using the correlation between sound velocity and visible light spectrum is preliminarily verified. This method has the characteristics and advantages that multiple data can be obtained within 1 s, synchronized with flow measurement, and the measurement is not limited by gas components and not effected by H₂. It is suggested to further carry out the research on accuracy, measurement range, precision and field application, and timely establish standard methods, level 0 test devices of calorific value direct combustion, gas compression factor, density and other test devices.