煤中氯含量测量不确定度评定

Evaluation of uncertainty in measurement of chlorine in coal

基于对煤中氯含量测量产生的误差与不确定度进行评定具有重要的意义,针对GB/T3558—2014 《煤中氯的测定方法》中高温燃烧水解—电位滴定法测煤中氯含量结果进行相应的不确定度评定。按照A、B类不确定度来分析与量化,重点对氯含量重复性测量、质量称量、硝酸银标准溶液的浓度及用量、电位测量、氯化钠标准溶液加入量的不确定度进行阐述,提出高温燃烧水解等不确定度对总量不确定度的合成影响不大,经过分析、量化、合成不确定度求得煤中氯含量的扩展不确定度为0.002 2%。

Based on that the evaluation of errors and uncertainties in measurement of chlorine in coal has significant difference,and regarding to results of chlorine determination using high temperature combustion hydrolysis-potentiometric titration method in GB/T 3558-2014 Determination of chlorine in coal,the uncertainty evaluation was done.According to the A,B type uncertainties,the analysis and measurement were done,and aspects such as chlorine content repeatability measurement,weight weighing,concentration and dosage of silver nitrate standard solution,potential measurement and uncertainty of sodium chloride standard solution addition amount were demonstrated,it was proposed that the uncertainty of high temperature combustion hydrolysis did not has big influence on the synthesis of total amount uncertainty,through analysis,quantification and synthesis of uncertainty,it was obtained that the extended uncertainty of chlorine in coal was为0.002 2%.