天然气在线分析的准确性和一致性(英文)

Accuracy and consistency of on-line natural gas analysis

关键词:  偏误差  不确定度计算  标准气体  在线天然气分析  一致性  气相色谱  对比技术

Key words:  bias error  uncertainty calculation  calibration gas  on-line natural gas analysis  consistency  gas chromatography  comparative technique

摘要:

对基于气相色谱技术的天然气在线分析的准确性和一致性进行了详细和系统的分析与研究。由于气相色谱技术是一种对比技术,因此标定气、分析仪的性能以及标定气的组分成为保障天然气在线分析正确性和一致性的关键因素。该文详细阐述了重力混合制备标定气的步骤,特别是EffecTech方法。同时,研究了分析仪的性能对于天然气在线分析的影响。具体而言,对偏误差与不确定度的分析进行了系统的阐述和详细的分析。通常偏误差和不确定度不可能以一种令人满意的方式结合。然而,目前普遍的做法是在不改变物理性质的前提下,接受组分含量测定所产生的误差。

Abstract:

The accuracy and consistency of on-line natural gas analysis using the gas chromatography method was investigated systematically and carefully.Since the gas chromatography method is a comparative method,the calibration gas,the performance of the analyzer and the choice of calibration gas composition are critical factors to obtain accuracy and consistency of on-line analysis.The gravimetric preparations of calibration gases,especially EffecTech procedures,were elaborated detailedly.At the same time,the performance of analyzer was studied.Specifically,the detailed bias error and uncertainty calculations were described and interpreted.Generally,bias errors and uncertainties cannot be combined in a satisfactory manner and as such,they are usually compared.However,it is now common practice to accept errors in the measurement of component amount fractions provided their effect does not give rise to unacceptable errors in physical properties.