煤的干基碳氢含量不确定度分析与评定

Uncertainty Analysis and Evaluation of Dry Basis Carbon and Hydrogen Content of Coal

依据JJF 1059.1-2012《测量不确定度评定与表示》及测定原理,分析了煤中干基碳氢含量的不确定度,主要包括空气干燥基煤样水分(Mad)、碳(Cad)、氢(Had)的标准不确定度,并对每个不确定分量进行评定计算。结果表明:干基碳氢含量标准不确定度分别为1.46%、0.02%,扩展不确定度为2.92%、0.04%。氢元素含量不确定度较小,测定结果精准度高。试样称量引入的不确定度对碳元素不确定度贡献略大,通过对电子天平定期检定校准提高测定结果精确度。

According to the standard JJF1059.1-2012 Evaluation and Expression of Uncertainty in Measurement and measurement principle,uncertainty of dry basis carbon and hydrogen of coal is analyzed.It mainly includes standard uncertainty of moisture(Mad),carbon(Cad)and hydrogen(Had)in air-dried coal samples,and each uncertainty component is calculated.The result shows that the standard uncertainty of dry basis carbon and hydrogen is 1.46%and 0.02%respectively.The expanded uncertainty is 2.92%and 0.04%.The uncertainty of hydrogen content is small and the accuracy of determination result is high.The uncertainty of sample weighing contributes greatly to the uncertainty of carbon.The accuracy of measurement results can be improved by periodic calibration of electronic balance.