煤中水分含量测定的不确定度评定

Uncertainty Evaluation of the Determination of Water Content in Coal

依据《煤的工业分析方法》(GB/T 212—2008)对煤的水分进行了测定,并参考《测量不确定度评定与表示》(JJF 1059—1999)分析了测量过程中不确定度的主要来源:煤样称量引入的不确定度、干燥后称量引入的不确定度、重复性测量引入的不确定度,在此基础上对各不确定度分量进行了评定,并计算得到了合成不确定度和扩展不确定度。最后提出了在测定过程中减小不确定度的有效途径,认为只有增加水分测量次数才能有效降低水分测定的不确定度。

The water content in coal was determined according to the Proximate Analysis of Coal（GB/T 212- 2008）. Referring to Measurement Uncertainty Evaluation and Expression （JJF 1059-1999）, main factors affecting the determination results of volatile content were analyzed as follows： uncertainties of coal sample weighing introduction, post-drying weighing introduction and repetitive measurement introduction. On this basis, various uncertainties were evaluated and calculated to obtain synthetic uncertainty and expanded uncertainty. Finally, an effective way of reducing uncertainty during measurement, which advocates the increasing of moisture measurement times to reduce moisture measurement uncertainty, was put forward.