气相色谱法分析煤层气组分含量的不确定度评定

煤层气组分含量测定准确与否,直接影响到煤层气资源储量计算的准确性与开发工程的成功率。不确定度是衡量测试结果可靠程度的重要指标,研究气相色谱法测定煤层气组分及含量时,结果的不确定度来源及评定方法。不确定度来源主要有三个方面:煤层气组分响应值重复性、标准气组分响应值重复性及标准气体的准确度。通过实验数据计算出各因素对结果的影响程度:标准气体的不确定度分量对待测样品的不确定度的影响较大,浓度较高的组分重复性测量引入的不确定度较大。煤层气组分的测量不确定度和组分含量有关,组分含量不同时,测量结果的不确定度也不同。

UNCERTAINTY DETERMINATION OF GAS CHROMATOGRAPHY ON COALBED METHANE COMPONENTS

A measurement of coalbed methane components is directly connected to coalbed methane reserve and successful rate of development engineering. Uncertainty is the key index in marking the reliability degree of measurement results, which comes from three aspects in response values repeatability of coalbed methane components, response values repeatability of standard gas components and accuracy of standard gas. Influence extent is calculated based on testing data of each factor. Uncertainty of standard gas has a larger influence on uncertainty of samples, repeatable measurements of high concentration components leads to higher uncertainty. Uncertainty of coalbed methane components is related to component concentration so that uncertainty of measurement varies with components concentration.