影响地表水高锰酸盐指数自动监测数据准确性的因素

地表水高锰酸盐指数自动监测仪器在实际应用中存在质控样测试和实际水样比对测试合格率相对偏低的问题。通过对高锰酸盐指数氧化还原机理的分析,结合目前国控水站对质控样品的测试数据,探讨了如何使用高锰酸盐指数自动监测仪分析测试得到准确可靠的水质监测数据。认为应尽量保持自动分析仪器的反应条件、稀释条件与标准方法一致,即取样量与试剂用量比与标准方法一致,并根据样品浓度变化实现量程自动切换,分量程进行仪器校准和测量,才能够提高自动分析仪器测量的准确性。

Investigation of Factors Affecting the Accuracy of Permanganate Index Automatic Monitoring Data in Surface Water

The relatively low passing rate in comparison between quality control sample test and real water sample test troubled the automatic monitoring instrument of permanganate index for surface water in in practical application.Based on the analysis of the redox mechanism for permanganate index and the test data of quality control samples in the current state-controlled water monitoring station,this paper discusses how to get accurate and reliable water quality monitoring data using the automatic monitoring instrument of permanganate index.Keeping the reaction conditions and dilution conditions of automatic analysis instruments consistent with those of the standard method,i.e.,keeping the ratio of the sample quantity and reagent dosage consistent with that for the standard method,automatic switching of measurement ranges according to the sample concentrations,and calibrating the instrument in different measurement ranges,are key factors to improve the accuracy of automatic analysis instrument measurements.