700nm浊度补偿在总氮水质自动分析仪中的应用

Application of 700 nm Turbidity Compensation in Water Quality Automatic Analyzer for Determination of TN

针对总氮水质分析仪测定浑浊水体出现吸光度偏低,甚至出现吸光度负值的问题,通过增加一路700 nm光路比色系统来进行浊度补偿,解决了总氮标液随浊度升高,测定结果不断降低的问题。实际水样试验室比对结果示值误差保持在±10%以内,加标回收率满足90%~110%。

In this paper,a method was developed for overcoming turbidity interference in total nitrogen(TN)water quality analyzer.Based on novel triple-wavelength colorimetric method,a separate 700 nm single-beam-colorimeter was introduced to normal TN analyzer,and the adsorption at 700 nm was taken as reference to eliminate turbidity interference.Proposed method was applied to analyze turbid water samples and TN value were consistent with the results measured by national standard method.Relative error of the actual samples was controlled within±10%,while the corresponding recovery rates was ranged between 90%and 110%.